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Hey im looking for a blacksmithing show around the illinois area. i have been a blacksmith for 1 year now and have started small knife work. so any info will help thanks!
   jv - Monday, 08/09/04 00:21:31 EDT

JV, Check our schedule of events page and our ABANA-Chapter.com page for a blacksmithing group near you.

In September SOFA/Quad State the biggest blacksmith tool market in the country is held in Ohio near Dayton. There are also verious demonstrations and lots to do. Its well worth taking a few days off to be there for the whole thing.
   - guru - Monday, 08/09/04 01:27:29 EDT

You are clearly well on your way to being in a lot of trouble..please accept my sympathys.
In light of the hithertoo admirable Quenchcrack's assessment of my work, I'd advise you to disregard anything else he has to say as he is slipping fast.
You might consider saving your big plate of brass for a bit and making your early mistakes on a smaller scale as the stuff is expensive and it's difficult to save a muff-up .
I found that there were a lot of experiments with a fairly high failure rate to be worked through on the way to a sound i could stand.
Try fine confectioner's sugar , sprinkled on the vibrating gong.It will show you the null nodes in the waveform by piling up where it doesn't wiggle. Mount/hang at the null points. For some reason, nylon cord damps the sound a lot less than other suspensions.
Listen as you hammer, you can hear the gong sound change and you can also hear the metal harden so you can anneal before it cracks. Once it cracks, an acoustically clean repair is almost impossible. If you leave it too crispy, it's apt to fail in use.
Expect to anneal it several times on the way to the final shape.
Listen to a good traditional gong. The ordered decay from one energy level/harmonic to the next and the next is pretty amazing. So is the lack of dissonance in the overtones.I never managed to do a satisfactory job of that.
Fair chance that the device of the turned bowl edge is a metal saving approach for getting a stiffer outside margin with a higher primary harmonic tone. The pitches too low to hear take up a lot of energy.
Do not take any of my advice seriously... just made it up as I went along..faking it the whole way.
The same thing will happen to you if you don't watch out!
Gong drive you nuts, having already driven you to the nuts.
   - Pete F - Monday, 08/09/04 02:17:00 EDT

good morning guru
could you tell me what is the best sort of marker to use for marking out steel prior to working in the forge i use french chalk at the moment but i have heard about soap stone and silver marking pencils are they any better
thank you regards david
   david .hannah - Monday, 08/09/04 04:10:32 EDT

David Hannah; Soapstone is about as good as it gets. Relatively cheap, too.
   3dogs - Monday, 08/09/04 04:44:21 EDT

David Hannah - Marking on steel.

I use a Prismacolor white pencil, I found that it doesn't rub off work pieces as easily as soap stone. And if dropped, the pencils less likely to break then soapstone.

   Don Shears - Monday, 08/09/04 08:34:57 EDT

Casey; did your picture need that precision? If not you have just wasted a lot of people's time. Like the tale of a fellow who designed something and took the plans to a machineshop and asked for a price---and was floored when they said $5000. He walked out and was grousing about it to a co-worker who said let me try it. Made one small addition to the plans and came back with a bid of $500. The difference was he had added a typical tolerance for machining. If they had to make it *exactly* to the dimensions it costs a whole lot more than if they can be a couple of thousandths of an inch off.

The Guru works with computers for a living, probably 12 hours a day; he's a proponent of what works best for the most people; not what's the latest toy. As my boss used to say "The folks out on the cutting edge of technology---BLEED!" course he was supporting a computer system that brought in 17 billion dollars gross a year for a world famous high tech organization---give you a hint think Nobel Prizes for such things as the transistor, 4 deg Kelvin background radiation, etc...

   - Thomas P - Monday, 08/09/04 10:52:03 EDT

Bell and Gong Tuning: Bell makers of old were a superstitious lot. Murphy and all his kin were permanant guests at the bell makers. Consider the Liberty Bell, and the fact that it had been cast 3 times with the same metal. I am sure the bell makers thought that the metal itself was cursed. Considering that bronze, like gold, has been recycled and reused over and over for millinia there IS a good chance that the metal WAS cursed. But that many pounds of bronze is too valuable to waste.

Bell shapes are shaped the way they are for very good reasons. The flare and the heavy edge of Western bells is designed to make a compatable overtone with the frequency of the smaller diameter above it. Since most such multiples are doubles it is difficult to do on a given object.

You also have to consider the difference between the Western and the Eastern system of notes. The Western system is a "tempered" scale designed originaly for the piano and adapted to every aspect of Western music. This scale abandonded pure mathematical scales based on whole fractions and even frequency values that were the earliest systems. That is why Western music sounds different than traditional Eastern music. I say traditional, because Western music is rapidly pushing out the old systems.

THEN there is the fact that most musical references flatly state that bells, triangles and drums have no "note" and cannot be tuned. . Which is a odd statement since all of these come in various sizes and "voices". Although a bell does not make one pure note, it has a primary and then secondaries as well as overtones that are roughly multiples of the same frequency.

Tuning of percusive vibrators is a very technical subject as well as an art. Someone mentioned steel drums. The tuning of these is VERY tricky. Each note is created by stretching the metal into a dome shape. There are usualy many on a drum and a set of drums will each be different. The problem is that you tune UP to a point, but if you go past you cannot go back. Then there is the problem of over thinning the metal. . .

Then there are those things you do not expect. I just knocked a hammer against an eye bolt welded to a 2800 pound piece of 18" steel shafting. It rang like a bell! Deep, throaty and with lots of sustain.
   - guru - Monday, 08/09/04 10:56:08 EDT

Well, sorry then I didn't know... ok well, to justify my not having any money... I am a guitarist too, I have 3 guitars that cost money, I am working, I am saving my money right now for some supplys, I am looking for a nice kit that has a book and some supplys. I am putting a web page together, and don't worry, I switched all of my .png files to .jpeg so it should be better. again sorry if I made anyone mad. I was just trying to get a rough idea of what might work.

   cwr89 - Monday, 08/09/04 12:05:45 EDT

Marking Metal: It depends on what the markings are for. For forging welding and cutting soap stone is IT. However, nothing except punch marks hold up at a forging heat. It has become the practice of many smiths to mark bends with or sharp chisle or punch marks, DO NOT DO IT! The cut mark makes a place that will form a cold shut in the corner OR a stress riser and increase the probability of breakage.

For general and rough layout on plate and benchtops as well as writing on forge hoods, soap stone is still the best choice. It can generaly be wiped off and doesn't contain any oil or wax that may lead to paint pealing.

When I first started blacksmithing I bought a box of soapstone (the rectangular kind). I think there was a gross (144) of the 6" long sticks in a the box. I break them in two or three and sharpen each piece on a grinder or with a file. I think I have only used a dozen pieces in 25 years. . . such is the efficiency of the one-man shop.

For picky layout for center punching or precision sawing white or silver pencils work on a smooth scale covered surface. On clean metal a Sharpie™ works best.

On machined surfaces or clean surfaces where a Sharpie™ is not fine enough you need to paint with toolmakers layout die. Then scribers are used. Back when my closeup vision was better than perfect I just used scibers on bare metal. I rarely have toolmakers dye (Dyekum) on hand on often just use whatever spray paint is on hand.

For permanent marking on stock and heavy beam you want one of those heavy ball point paint pens like junk yards use. Those for permanent marking have acid in the paint and will stick on paint AND etch the metal through paint and grease. They will even etch glass. These will RUIN sheet stock and other material where you want an unblemished surface. When painted the marking will often show through even if the metal has been cleaned by sandblasting or etching. You would have to prime and sand out the marking.

Delivery of work covered with Dykum or other marking paint is not good craftsmanship. Clean it off.
   - guru - Monday, 08/09/04 12:09:30 EDT

here is an uncompleted version of my tools section


I am sorry agian if it is in a resolution that is too large
   - cwr89 - Monday, 08/09/04 12:14:52 EDT

here is an uncompleted version of my tools section


I am sorry agian if it is in a resolution that is too large
   cwr89 - Monday, 08/09/04 12:15:12 EDT

Where can I find info on a #1 Meyer (Mayer?) Bros. power hammer?
I've been told it's a knock-off of the 50lb Little Giant.
Is it a decent hammer to aquire as long as it's in decent condition (like new, I'm told)??
I caught a brief mention of Mayer at the top of this page, but not too much elaboration on it...
Thanks kindly.
   Wendy Lawrence - Monday, 08/09/04 12:25:24 EDT

Little Giants: Wendy, Meyer Bros. ARE Little Giant. The brothers were the designers and makers of these machines and Moloch as well. Most Meyer Bros. are the earlier model with the wrap around guide system instead of the dovetail guides. Although the late model dovetail guides are considered by SOME to be an improvement they are not. Once the dovetail guides are worn they are expensive to remachine straight (the wear curved). The late models also have the read mounted clutch which is also problematic. When the clutch bearing wears it becomes very hard to control. The early line shaft drive center clutches work well even when worn out completely.

LG Specificationss are on our Power Hammer Page. Note that the Meyer Bros. hammers are a little taller than the LG's. The difference is the later models have the link coupling above the crank pin instead of under it. On a 100# hammer this lower the hammer 4" and saved 30-40 pounds of iron.

There is no such thing as a #1. They all were either marked with the ram weight in pounds or not. They also had a name, Babe, Boy, Man, Giant, Jumbo (25, 50, 100, 250, 500)
   - guru - Monday, 08/09/04 13:16:07 EDT

Casey, no problem I just wanted to point out that though we often talk like "blacksmiths" there is a wide range of backgrounds out here; or as I like to put it "You don't have to be a rocket scientist to be a smith---but I know several who are!"

Looking at your set up I'd say you need to look into a bigger anvil; you generally want your anvil *much* bigger than your hammer, 40 times is a good start, more *is* better.

However if you can't find a bigger chunk of metal a large sledgehammer head inset (vertically) into a good stump will get you started.

   Thomas P - Monday, 08/09/04 13:50:15 EDT

As I remember, "French chalk" IS soapstone.

I guess I'm on the non-cutting (and stress riser) edge when I use my slightly dupp center punch for marking. It also tends to hold just a dab of soapstone from the line, so it gives a little quicker guidance at higher temperatures. I've found a 100 watt bulm in a goose-neck mounting to be quite useful for showing up the soapstone marks at the anvil of vise.

Sunny and actually getting warm on the banks of the Potomac.

Visit your National Parks: www.nps.gov

Go viking: www.longshipco.org
   Bruce Blackistone (Atli) - Monday, 08/09/04 14:03:07 EDT

hi i am looking to build a pipe forge i have been looking for some designs i have built a brick forge and i wanted to try and build a pipe forge that could do forge welding can you tell me where i can get simple plans if possible
thank you david
   david .hannah - Monday, 08/09/04 14:09:56 EDT


The number ONE rule of HTML is to resize your images in a graphics editor NEVER use the HTML to resize images. It is a huge waste of bandwidth and everyone's time. An image resized 50% is 25% the file size with no compression and therefore loads 4 times faster.

Also note, Tripod is notorious for its pop up advertising. As a new account yours doesn't have any but it will in a day or so. We no longer link to Tripod sites (or others with pop-ups) and I am slowly weeding out all the old tripod links.
   - guru - Monday, 08/09/04 14:10:48 EDT

David, Look at our plans or FAQs pages. The gas forge information on both have links to Ron Reil's web site. This is THE place for DIY gas forge information. READ the details.

We sell the Kaowool and ITC-100 for building these forges.
   - guru - Monday, 08/09/04 14:15:05 EDT

Sorry guru, first off, I know absolutly nothing about html, I did that in front page. but I will work on the graphics and what not, I am also going to probly rewrite the whole thing with a different layout. I will also switch to geocities, I use that for other things, but I was wanting to try out tripod. thanks for the info.

I will rewrite it and when it is final, I will post a link.

I have also started working on my forge. I will post some pics of that up later.

   cwr89 - Monday, 08/09/04 14:40:22 EDT

MS FrontPage: This is one of the worst editors on the market. It is only worth what most people pay for it (0).

The two main problems are, first that it lets you insert code inside tags where it doesn't belong. This is a serious problem with WYSIWYG editors. MS word processors do the same so that you end up with formating tags spliting words and vice versa. In programing this is a serious problem. New pages are not too bad but every edit creates more new errors. The second problem is it overloads the code with MS comments that are repetitive and make the HTML very hard to find. AND on some pages create a significant page load burden. All those comments are transfered and in browser memory for nothing. .

Get a book (a small cheap one) and learn HTML. The only way to edit and maintain pages is to understand the HTML structure. See our FAQ on websites for craftsfolk. It has some brief code examples.

   - guru - Monday, 08/09/04 15:46:18 EDT

do I write to code in frontpage or do you recomend another program?

   cwr89 - Monday, 08/09/04 16:00:37 EDT

Howdy! I've been approached by an inventor friend about doing a production run of 90* bends in 1 inch, .095 wall mild steel sq. tubing. probably 8 inch radius. I have a 2200# platen, and built an adjustable roller nose lever, like in the 'benders 3' page here. I haven't tried using this set-up on sq. tube yet, would it be probable? We found a cheap free standing roller in a catalog, it looks like it crimps in the inside face of the tubing to ease bending.
Any thoughts appreciated, thanks, mike
   - mike-hr - Monday, 08/09/04 17:26:24 EDT

Howdy! I built an adjustable roller nose lever like the one in the 'benders 3' page here, could it be used on the platen to put 90*, 8 inch radius bends in 1" .095 wall sq. tube? I've been approached to do a production run of these, wanted to ask for input before building a fixture.
Many thanks, mike
   mike-hr - Monday, 08/09/04 17:35:30 EDT

You can actually write the code in notepad and then point to the file with your favorite browser to see how it works.

I use Arachnophilia, a "Care Ware" free html editor (colors commands and the like).
   Escher - Monday, 08/09/04 18:02:28 EDT

Linda-- Can't see where anybody has responded to your wrought iron gate query yet, so let me try. A real blacksmith can certainly make a medium sized Scottish thistle. Or a large one. Or a small one. Or make anything else your heart desires. And weld it to your wrougnt iron gate, too-- even if it should happen not to be real wrought iron but plain old square tubing.
   Goods Inward - Monday, 08/09/04 18:02:37 EDT

PeteF, yeah, yeah, yeah, but is the check in the mail? Saaaaaayyy, you didn't star on The Gong Show did you?
   Quenchcrack - Monday, 08/09/04 19:30:50 EDT

I have a 50# "little giant" hammer and we have just finished rebuilding it. The question I have is I cannot find a place to lubricate the clutch pully. It is a center clucth disign. About the only way I see it can be done is spuirt oil at the front and back. I don't see how this would be long lasting.
   Fred - Monday, 08/09/04 21:58:56 EDT

Hi all I have just finished restoring an old spring hammer as far as I can tell it is approx. a 50 pound little giant or equivalent it has no brand name and I understand that it has been in Australia for at least sixty years if not longer.
It is Ok overall and in good condition the bearings have very little wear and the hammer sleeve is free from gouges and scratches.
I have it mounted on a welded steel I beam pad that has been weighted down and then attached to the bedrock, it moves a little bit but does not bounce around the workshed, more weight I feel will make a difference there. The real problem is the v belt pulley cone I have a 3 HP motor at the suggested speed for the equivalent Little Giant but after a few hours use the clutch seem to be slipping and won't lift up the hammerhead, there no no lack of power from the motor but when I push the foot lever clutch the pulley engages slightly then spins . Any suggestions I need to finish a forging commission and cannot spend more down time with this?

PS I have just seen the power hammer videos on your web site I wish I had known of them before I started the restoration

Regards Greg House

   Greg House - Monday, 08/09/04 22:18:23 EDT

Greg-- have you tried oiling the clutch? Sounds nutty, I know, but my 50-pound Meyer Bros. copy of their Little Giant likes to have some WD-40 sprayed into its clutch every now and then. Slips some at first but then stays happy for another while. (Note to the pouncers: you know and I know WD 40 is not an oil. But my hammer doesn't, you see, and that's what counts.)
   - Miles Undercut - Monday, 08/09/04 22:51:42 EDT

Wendy-- Dunno re: the Mayer Bros. #1, but I've used my Mayer Bros. B-90 50-pounder since 1991 and as long as it is happy with itself, it is a fine machine. Trouble is, as Richard Kern notes in his book, the Little Giant is a machine constantly bent on destroying itself. The bros were not too great in the harmonic balance dept. Also, note especially what will be involved in replacing the drive belt. On mine the clutch pulley is thoughtfully positioned amid the cast iron yoke, meaning the whole contraption has to be dismounted. Etc. I think there are better ways to spend time and money unless you just happen to love old tools.
   Miles Undercut - Monday, 08/09/04 23:28:07 EDT

Little Giant Center Clutch Lubrication: Fred, All of the examples of this model that I have had (3) and seen (many) had a grease cup (original) or zerc fitting on the back of the shaft. The shaft is gun drilled the long distance to the middle of the clutch. If the grease cup has been broken off as is common or just missing it is easy to mistake the small hole for a shaft center.

It is common on old hammers for the grease to harden in this long slender hole and be difficult to force lubrication in. In that case it must be cleaned out.

The center clutch bearing is the ONLY place on the Little Giant or Meyer Brothers hammers that is greased. All other points are oiled daily and after every couple hours of use.

The clutch linings themselves must be oiled. The cone clutch used in Little Giants is NOT a good slip clutch. Cone clutches are are a positive engage/disengage clutch. To slip them they must be kept wet with oil.

Any Little Giant that has been used for more than a few hours should be dripping with oil. If not, it is underlubricated.
   - guru - Tuesday, 08/10/04 04:54:25 EDT

Re Oiling or lubricating little giant copy
OK I seem to remember that a grease nipple was on the tail end of the shaft (now missing probably during the move)I will replace it and re grease the centre bearing.
On oiling the clutch linings on inspection this could make sense they seem very dry and to my knowledge in the past decade have never been lubricated (mind you in that time they probably only saw twenty hours use if that).
Since we have had almost continual drought for the past five years I am not surprised that any remaining oil has evaporated
Thanks for the suggestions
Regards Greg House
   Greg House - Tuesday, 08/10/04 05:03:20 EDT

Little Giant Belts: Center clutch Little Giants were designed for flat belts going to a line shaft. These belts where (and are) spliced in place. Early splices were glued or leather lacing. Late splices were pattent metal connections such as Aligator laces (clumbsy) or Clipper wire laces. Modern nylon belts are often glue spliced in place. Leather and ruberized cloth belts use Clipper lacings and can be purchased from power transmission suppliers custom made to length. These are installed by slipping a gut or teflon coated wire pin into the interlocking wire loops.

If you have much old flat belt machinery you need a Clipper belt lacer if you do not live close to an industrial belting supplier.

Many old Little Giants have been converted to using endless V-belts. This does indeed require unbolting the bearing caps and lifting the shaft. Considering how long belts last it is not a big ordeal to do once a decade or so. It is not nearly as bad as dissasembling some lathes that have V-belt drives. . .
   - guru - Tuesday, 08/10/04 05:11:58 EDT

No Name Hammer in OZ: I suspect this is a localy built copy and the clutch may not have the same characteristics as the true Little Giant clutches. The only time I have seen a Little Giant clutch that could not lift the ram was when the ram guides were adjusted too tight. The guides must be snug but absolutely free to move full travel. Worn rams and guides are difficult or impossible to adjust properly. Ocassionaly a snug ram will heat up during use and become too tight.

The guide adjustment test used by Dave Manzer is the ram "bounce" test. If you have retrofitted a brake, at any ram position you should be able to cause the ram to bounce up and down freely on the springs. If the ram is not free to bounce up and down, it is too tight. As always, oil, oil, oil.

Little Giants have two types of clutch in several combinations. The center clutch is a deep cone clutch that has riveted on cotton belting friction material on the inside cone. In some cases this has been replaced with asbestoes brake lining. This is wrong. I have also seen early Meyer Bros. hammers running metal on metal.

Late Little Giants had a rear mount clutch that was open to the back. Most of these were V-Belt models but there were a few flat belt models built. These clutches have maple wood blocks for the friction material. It is common for grease from the center bearing to spin out and get on the clutch. Grease will cause the clutch to slip. Clean the grease off the parts and oil the wood blocks. Then be careful not to over grease the clutch bearing. But be SURE to keep it lubricated.

Rear mount clutches can become very irratic if the bearing wears. This is due to the pulley dropping down and the narrow wood blocks no longer being centered. Center clutchs can be very worn and not have this problem.
   - guru - Tuesday, 08/10/04 05:33:48 EDT

Is there a limit to how many times you should fold a katana. i mean is there a point at which you can fold it to much and the metal becomes weaker?
   Patrick - Tuesday, 08/10/04 10:58:27 EDT

I dunno, I have one at home that I received as a gift, it looks nigh on impossible to fold. I suppose if I heated it up some, but I don't think it would be a good idea, regardless.

That said, most of the bladesmithing books I have read don't fold more than 10-15 times. The only reason you would fold at all is to create homogeneous steel using poor initial steel, or through some planned/unplanned damascus patterning affair.
   Escher - Tuesday, 08/10/04 12:02:21 EDT

But as always, I could be wrong.
   Escher - Tuesday, 08/10/04 12:03:27 EDT

Patrick, you don't fold a katana; you fold a billet that then can be made into a katana. And the answer is yes. The reason that traditional japanese swords were folded was to homogenize a very erratic starting material and to drop the carbon content from nearly cast iron down to a medium carbon steel. If you continue to fold and lose carbon you can get it to where it won't harden ---this is generally considered to be a bad thing in a blade steel...

Note: what they were trying to get was a homogenous medium carbon steel---guess what? you can pick up the phone and order such a steel and UPS will deliver it to your door!

   Thomas P - Tuesday, 08/10/04 12:08:38 EDT

Thomas, assume for a moment we're talking about an actual katana: Most of them I've seen would be completely ruined after one episode of folding, most of them to the point where they'd break at the bend...Therefore, I'd say that the metal becomes weaker with one fold, but only at the fold. (insert evil grin here) You guys are too nice! At least nobody compared it to tuning a fish...
   Alan-L - Tuesday, 08/10/04 14:14:21 EDT

Folding: This term is also a misnomer. Blade steel is cut, stacked and welded. The cut is sometimes just barely incomplete and acts as a hinge to help hold the pieces in alignment but it is not a "fold" although commonly called a fold.

If a billet were actually folded the ends where the layers are vertical would not thin out like the rest. Nore would they develop in a good pattern. These would become waste and need to be cut off and discarded. Too much effort goes into forging and welding to waste any more than is necessary.

Those that only know what they hear from movies and other inaccuarte sources talk about "folding hundreds of times". The fact is there are hundreds of layers but it does not take hundreds of "folds". If you start with the simplest of billets, just two layers the progression is a shown in the first table. The other tables show more typical steps.

2 Layer Billet, cut twice
Heats 1 2 3 4 5 6 7
Layers 2 6 18 54 162 486 1458

4 Layer Billet, cut twice
Heats 1 2 3 4 5 6 7
Layers 4 12 36 108 324 972 2916

8 Layer Billet, cut twice
Heats 1 2 3 4 5 6
Layers 8 24 72 216 648 1944

16 Layer Billet, cut once
Heats 1 2 3 4 5 6 7
Layers 16 32 64 128 256 512 1024

16 Layer Billet, cut thrice
Heats 1 2 3 4 5
Layers 16 64 256 1024 4096

Production bladesmiths often use many thin layers to start. This reduces the number of welds. As you can see, in five heats (cutting and welding) you can get a tremondous number of layers depending on how many cuts are made. Two cuts makes three pieces which is common. Three cuts make four pieces. When you forge a 400 layer billet to blade thickness you easily get layers that are less than a half thousandths of an inch thick.

Part of the art is not just making a better steel from bad, it is also the art of developing layers and patterns that show when etched. And as you can see, the smith making steel from two layers only needs to make 6 or 7 welding heats to make a tremondous number of layers.

   - guru - Tuesday, 08/10/04 14:20:14 EDT

NOTE: The same number of cuts do not need to be used every time. Using different numbers of cuts you can control the number of layers to almost anything you want.
   - guru - Tuesday, 08/10/04 14:28:54 EDT

The estimable Guru, as always, is correct. My Mayer Bros. B-90 indeed spent its formative years running off a line shaft. However, the previous owner sometime about 60 years ago, fitted it with a monster 3 phase 1 h.p. motor using a V-belt. The shaft does not have bearing caps, alas. Soooo, it has to be pulled when and if. Also, just as the Guru says, it had no zert. Instead it had one of those cute l'il ol' twisty-squeezer grease caps-- tighten it up and it forces the grease into the shaft. However: the grease inside the yoke was gunked totally solid when I got it. A warm brazing rod loosened it up pronto.
   Miles Undercut - Tuesday, 08/10/04 14:35:51 EDT

CSI Board Meeting Tonight at 10 PM EST In the members business forum. All members and gurus are invited. Just remember this is a board meeting. Hopefuly I will have everything ready! Now off to the PO and UPS. .
   - guru - Tuesday, 08/10/04 15:02:15 EDT

Welding broken blades: in northern European mythology there is a theme of welding up broken blades to make a "super sword", this there has made it into modern times with narsil being reforged in LoTR.

I once sat down and as a gedanken experiment tried to figure out if there could be a nugget of truth behind the legend.

So why would a sword break? Possible reasons: Too high carbon/inhomogenous carbon distribution, poor heat treat, bad inclusion or bad weld.

Re-welding the blade would tend to lower the carbon content and through carbon migration make it more homogenous. It would also refine inclusions. Also it would tend to help out iffy welds. You then have the chance to re-do the heat treat. All in all it might just work!

Of course filing the blade down and feeding it to geese, collecting the "end product" and re-refining it might help out an early blade too, nitrides you know...

A blade that "folds" would be indicative of very bad heat treat or very low carbon, only one of which might be helped by re-forging...
   Thomas P - Tuesday, 08/10/04 15:41:55 EDT


Turn the folding message into a FAQ!
   Paw Paw - Tuesday, 08/10/04 17:35:34 EDT

HMMM, Miles. Re: the "#1" Mayer Bros hammer.
I do love old tools, but truth is, I am a lazy mechanic. Sounds like me and that old machine might not get along very well.
What is the book by Richard Kern you refer to?
   Wendy Lawrence - Tuesday, 08/10/04 18:14:26 EDT

Howdy. I want to say first of all that i am a 15 year old novice smith, using coal and charcoal on occasions. With that said, i now want to build a gas forge. Yes, i have checked out the links and faqs and all of ron reil's info on his website, and found it all very useful. I have figured that something the size of a freon tank forge with an E-Z burner would work great for what i want to do, which is small stuff, like skewers, for an hour afterschool. I have looked at commercial forges availabe, and, well, i dont have the money for that, which brings me to building one. Is it possible for me, someone who has never used or worked around a gas forge before, and done very little work with plumbing, to build a propane forge. I plan to make the chamber out of firebrick. And would it be a good idea to build one or just ask santa, aka Mom, for one?:) and would it be safe( my Mom's, and admittedly mine as well, big concern). What do you recommend. I am open to all comments, which i say thanks a bunch for, in advance.
I sure do appreciate any replies.
Ian WIlle
   Ian Wille - Tuesday, 08/10/04 18:20:44 EDT

Wendy-- The book is The Little Giant Powerhammer, by Richard R. Kern, H&K Publishing, P.O. Box 284, Xenia, Ohio 45385, February 1992, ISBN 1-880173-02-6 in paper, -03-4 hardback. As I recall, Kern was in the process of relocating at the time the book came out, to Colorado, I think. Harlan "Sid" Suedmeier, 420 4th Corso, Nebraska City, Nebraska 68410, phone 402-873-6603 days, 4372 evenings, bought the Little Giant inventory when they packed it in, has parts and lots of know-how, can probably answer any of your questions. Guy I went to smithing school with has rebuilt several Little Giants, hates them devoutly, plans to get an air hammer for his new shop. Don't let that-- or me-- talk you out of getting one. You can always sell it if you don't get along. Mine is cranky, but considering its age-- around 70 or so, maybe 80-- it is a thing of beauty and a joy forever, not to mention handy as hell getting a scroll on the end of 1/2x2 railing. It does help, however, to be able to forge a new toggle link every so often when it gets really nasty.
   Miles Undercut - Tuesday, 08/10/04 18:34:35 EDT

Ian, it is hard to judge your abilities and responsibility from a distance. Gas appliances can be dangerous (even commercial ones), and leaking propane can and often is the cause of serious fires. In the 1970's trailer homes had poorly designed commercial gas furnaces in them and thousands burned killing and maiming hundreds of people. It seemed like a daily news event for YEARS. . The result is that many places have stronger laws on propane than natural gas.

That said, a gas forge is not much more dangerous than a propane grill or gas camp stove. The exception is the nearly invisible dragon's breath that often extends a foot of so in front of the hearth. Few smiths that use gas forges have much hair on their forearms and ocassionaly lose eye brows. . .

Unless one of your parents are very mechanical and one agrees to help with this project then I would say look for some help. Plumbing fitings are a little mysterious until you have fooled with a few. Look for your local ABANA affiliate (check ABANA-Chapter.com), go to a meeting or two and see if you can talk one of the fellows there into helping build your forge. Besides finding someone knowledgable you may also find someone with a few tools like a drill press and a welder to help with the project. Tell other folks about your project as well. You never know where help is.

I have two recommendations.

1) Build one of the burners that use a MIG welding tip for the gas injector. These are not fool proof but they make it close to. See our gas forge FAQ and my burner design.

2) Use Kaowool to build your forge. The light weight high efficiency insulation lets your forge heat up a lot faster, it is easy to work with AND the result will be light enough that you can carry it in one hand. The cost of a 10 foot roll and a jar of ITC-100 to coat it with is about $85 plus shipping. You should be able to build your forge for less than $150 using new materials except for the shell.

The light weight and resulting portability are a big plus for hobby smiths that do not have a permanant place to setup in. Light weight insulated gas forges cool off quickly for storage.
   - guru - Tuesday, 08/10/04 19:12:08 EDT

hello all, just a quick question, is there a way to find out the BTU (british thermal unit) out put of a home built gas forge? Thanks
   jody - Tuesday, 08/10/04 20:03:50 EDT


One thing I think I can add is that building a gas forge is a lot easier if you can play a working one first. I didn't. It's hard to figure out what's wrong with your forge when you're not sure *if* something's wrong!

If I'd just asked at my local guild, I'm sure I would have had lots of invitations to come play. I'm still kicking myself for not asking. It all worked out, but took longer than it should have.
   Mike B - Tuesday, 08/10/04 20:07:00 EDT

One thing to keep ever in mind with gas-- propane-- forges is, they put out a humongous excretion of invisible but ambient and fatally toxic crud. Friend and I worked with one, small, two burners running off a barbecue tank, inside my shop, doors open, lots of ventilation, for most of an afternoon, until we both abruptly realized we were on the verge of becoming dead, and with hellacious headaches. Even outdoors, there is always a cloud of nasty around the forge. Caveat.
   Juan leGubrious - Tuesday, 08/10/04 20:43:40 EDT

The most toxic of the fumes from a gas forge is Carbon Monoxide, IIRC. I have a CO detector in my shop for just that reason. they are less than $15 at your local big box store, and are usually manufactured by First Alert.

How much is your life worth to you?
   Paw Paw - Tuesday, 08/10/04 21:01:13 EDT

jv. I've demoed for the Illinois Valley Blacksmith Association twice. Check out info@IllinoisBlacksmith.org.

I've been using the Presto! Jumbo Correction Pen for a lot of my metal marking. It's not as precise as a scribed line, but for torch cutting, match marking, and other uses, it holds up to heat fairly well and stands out like an outhouse in a fog.

David .Hannah, Is a pipe forge a pipe with a closed end, the air comes in the other, and it has a bunch of drilled holes in between for the tuyere? If so, in my opinion, they suck canal water.

Stacking and welding. The lore from the early days of Spain says that the apprentices and journeymen farriers would take old horseshoes, make a sandwich of two or three worn ones, and faggot weld them into a bar. The bar would then be turned and become a "new shoe". Furthermore, it was claimed that the quality and wear factor of the welded shoe was much greater than shoes made of plain, W.I. stock.
It's likely that the latter statement was a crock. I suspect that the idea of making shoes from old shoes kept the shop busy, especially when floor work was slack.
   Frank Turley - Tuesday, 08/10/04 23:14:55 EDT

Hello I am wanting to start in the craft of BlackSmithing and I was wondering where I could find information of the craftign of swords and armor. Any help would be appreciated
thank you.
   Freshtv - Tuesday, 08/10/04 23:58:13 EDT

Freshtv, See our Armoury page and FAQs pages. Our Swordmaking FAQ has a whole page of references.
   - guru - Wednesday, 08/11/04 00:40:38 EDT

Forge BTU, This is a tricky question on any forge, kiln or furnace. The general method is to measure the amount of fuel used in a period of time and then use the BTU value for that volume of fuel. For a propane forge this is pretty simple. The Fuel bottle is put on a scale and weighed. Then the forge is operated for a period of time (an hour or two) and the bottle weighed again. Then the number of pounds of fuel consumed per hour is known. Multiply pounds per hour by BTU per pound and you have it.
   - guru - Wednesday, 08/11/04 00:45:49 EDT

Better wrought crock:-)

Same thing was said in the english countryside, 2-3 shoes could be forge welded back into one good shoe. Recycling is nothing new, and forgewelding was a way of life in times past:-)

Charcoal+very light air blast+correct placement in the forge=carburizing flame. Wrought welds more easily over a wider temperature range, and with proper technique could be improved with welding... Decarb is not gaurenteed when you weld:-) Watched Rick Furrier's Dirt to Dagger demo at Quad State last year and he carburized some wrought in a charcoal fire and then blisted some wrought and made shear steel was quite a demo:-)
   Fionnbharr - Wednesday, 08/11/04 01:09:01 EDT

we are currently fabricating custom copper countertops and one of our customers has asked us to age the copper for him,are there any chemicals that we can use to do that quickly?I realize copper patinas quickly on it's own but often leaving fingerprints or ugly patterns and we are trying to get an even patina.Thank you.
   - annette - Wednesday, 08/11/04 10:02:45 EDT

Coal forges put out fumes too; but you can *see* it and the smoke usually demands it be dealt with.

Propane forges, charcoal grills and gas grills also put out toxic fumes but they are generally invisible so folks don't realize what they are getting into.

BTW I've lost my facial fur more often to coal forges---especially when coking up a bunch of green coal.

   Thomas P - Wednesday, 08/11/04 10:32:07 EDT

sorry to be a bother but I want to know what tep does cast iron mest at?And can most froges get to that tep?
   - John S - Wednesday, 08/11/04 12:01:41 EDT

sorry i meant melt not mest
   - John S - Wednesday, 08/11/04 12:03:03 EDT

hello again i have been looking at the designs for the pipe forges on the net and i'am impressed with some of then compaired to my brick forge i was speaking to a refractory stockist and he suggested using strips of 1400 grade board cut at angles and arranged like a whiskey barrel then placed and bonded inside the pipe has anyone ever done this before or is it not practical he said it would be harder wearing and better insulation would be acheved ??????
   david .hannah - Wednesday, 08/11/04 12:48:27 EDT

David Hannah, I think he was trying to line his pockets at your expense. Kaowool/inswool is the most efficient insulator, period. A coat of ITC-100 on top will protect the lining from most mishaps, and a piece of kiln shelf on the floor will help with flux damage. A gas forge doesn't have to be elegant-looking to work well. Many smiths I know take great pride in the funkiness of their forges.

John S: about 2400-2700 degrees F, depending on alloy. And, all coal or charcoal forges can do it, not that you'd want to, and many gas forges can as well. If you want to cast objects, do a search on home foundry sites, specificaly crucible furnaces. Steve Chastain and Stewart Marshall have particularly good sites.

Annette: yes. Unfortunately I don't know what they are offhand, but someone will chime in soon, don't worry.
   Alan-L - Wednesday, 08/11/04 13:48:20 EDT

Annette-- The Birchwood-Casey (gun bluing, etc.)people-- phone 952-937-7931-- have vast experience in patinating metals, have a helpful technical department for just such questions. Beware, though, that although they sell bluing in teency bottles and steel coloring (Presto Black) by the gallon, they tend to think in vast production runs of stuff, dip coloring, dip rinsing, etc. So try to get them to talk about your problem step by step. Me, I think I'd experiment on little panels: try Coca Cola, swimming pool chlorine, salt water, a soupcon of muriatic. Adventure!
   Goods Inward - Wednesday, 08/11/04 15:03:07 EDT

Now as an add on question: At what temperature do most cast irons get poured at? Melting temp is not usually pouring temp for most metals. For simple cast iron a cupola furnace works very well---Stewart Marshall's pages should explain a lot.

I have seen crucible furnaces made by sawing soft firebrick and doing barrel stave construction. No pipe though just a couple of SS "hose clamps".

   Thomas P - Wednesday, 08/11/04 15:19:32 EDT

Forge Lining: David, Refractory board is, as noted, much more expensive than the wool. By the time you cut up all those pieces you would have a mess. The consistancey of the board products is like crumbly ceiling tiles. It can be easily cut but it is easy to damage. Rubbing pieces together or sliding it tears chunks off and makes a dusty mess. Board should only be used with the least cutting and for flat surfaces only.

The blanket material is as good an insulator, much easier to handle and conforms to curves much easier. In "pipe" forges it is self supporting due to the arch effect. Once it is covered with ITC-100 it is not going anywhere.

Neither board or blanket are suitable for forge floors. A hard refractory is needed. Half thick refractory bricks work best. Some folks put the bricks over blanket and support them with standoffs. However, I have found that unless you are going to load a forge up with heavy billets that the compressed blanket will support the brick just fine. I usualy split a strip of blanket and use scraps to fill in between the curved blanket and the flat brick.
   - guru - Wednesday, 08/11/04 15:37:59 EDT

Annette, Dont remember the details, but David Marks on "WoodWorks", (furniture maker on DIY satellite network) made a table with patinated copper and he had very specific info on a couple of colors/patterns. Might check out DIY-TV for details.
   - Tom H - Wednesday, 08/11/04 16:16:57 EDT

Copper Coloring. Some chemical formulas are found in Oppi Untracht's book. "Metal Techniques for Craftsmen", PP.415 through 419, Doubleday, Garden City, NY, 1968. I would be sitting here a long time if I typed the material for you. Also, Bryant Lab in Berkeley, California, used to furnish chemicals and info on patinating.
   Frank Turley - Wednesday, 08/11/04 19:49:46 EDT

Hello .I'm a working smith of moderate ability. I have come across a blower from the "Electric Blower Co. Boston Mass,"
Do you have any knowledge of the history of the company or where I could find some.
Thank You
Marc Hilden
Narrow Lane Forge
Huntsville Al.
   Marc - Wednesday, 08/11/04 21:02:50 EDT

Annette: here's a list of 32 different patina formulas for brass, bronze and copper.

   AwP - Wednesday, 08/11/04 21:22:35 EDT

How do you bend an off-set in a flat bar, using a press,home made tooling or a smithing magician. The off-set would be bar thickness
   fred - Wednesday, 08/11/04 23:02:15 EDT

Fred, There is an example of such a tool in our iForge demo on press tooling. iForge page, Demo #162 Flypress Tooling, Glass Clip Die.

Be sure to look at all the tooling demos and details. There is lifetimes of inventiveness there.
   - guru - Wednesday, 08/11/04 23:20:16 EDT

Electric Blower Co. Boston Mass Marc, I have never heard of this one. You are talking about an era (1890's - 1930's) where thousands of small companies came and went. As is much of industrial history these things are often poorly documented and difficult to find information on.
   - guru - Wednesday, 08/11/04 23:25:31 EDT

hello guru
i was wondering if you could help me find a place in ohio that does heat treating. i need a l-6 katana blade heat treated but i cant find a place that does it. i would do it myself but cant get a blade that big to 1500 degrees and hold it at a steady heat for 30 min. i will do the tempering myself(not that l6 needs and, but just to be safe). i found a much easier way to do differencial hardening. i just harden a blade then heat the back of it with a torch while cooling the edge with a wet rag. its better than the clay method, sometimes when i use the clay method the clay cracks of or the hardened part splits at the hamon away from the back of the blade! the only downside to the torch methos is i have to forge in the curve to the blade, with the clay method it happens naturally
thanks for your time and help
   matt - Thursday, 08/12/04 02:59:02 EDT

If you're willing to send it as far as Michigan, Keven Cashen is a bladesmith and metallurgist who does alot of L6 work, he might be willing to do it for you.

What you describe with the torch is actually differential tempering, not hardening. The practical end results are pretty similer with hard edge and soft back, but there's some pretty big differences to call it the same thing.
   AwP - Thursday, 08/12/04 04:29:09 EDT

Matt, All I can say is let your fingers do the walking. Almost every major city in Ohio will have one or more heat treaters. At one time Cincinatti was the machine tool capital of the world. Cleveland is full of industry of every size. If you cannot find them listed in the phone book then call some machine shops. Many do their own heat treating. If they do not they may tell you does.
   - guru - Thursday, 08/12/04 05:02:39 EDT


In the past few days our server has experianced some hard drive problems. We are scheduling maintenance for the wee hours tomarrow. Hopefully it will last that long. . .
   - guru - Thursday, 08/12/04 10:10:32 EDT

Matt, it is generally a bad idea to space out the time between hardening and tempering in a heat treat. The differential tempering method does not produce a hamon like the differential hardening method either.

   Thomas P - Thursday, 08/12/04 10:35:50 EDT

Tuesday, 08/10/04 04:54:25 EDT you said.

"The center clutch bearing is the ONLY place on the Little Giant or Meyer Brothers hammers that is greased. All other points are oiled daily and after every couple hours of use."

Now running on the principle that a stupid question is easier to answer than a stupid mistake is to fix, why wouldn't the main bearings be greased?
Are there advantages to oiling babbit bearings?
   JimG - Thursday, 08/12/04 14:08:21 EDT

LG Lubrication: Jim, Those bearings were DESIGNED to be oiled. The choice to grease the clutch bearing was because of access and oil flow, not because it is a better lubricant. Oil works better at the shaft surface velocity than does grease.

Other places that improperly get greased and clogged up are the ram guide lube holes on the ram of the wrap around guide hammers. These often get grease or bug dirt in them and then painted over. There are also small lube holes in the toggles on some models. They are small, they are there, look for them, clean them, oil them.
   - guru - Thursday, 08/12/04 14:49:58 EDT


It is my understanding that babbit needs a constant and continuous supply of lubricant. Unlike ball or roller bearings, there is no place for any residual grease to collect, so the babbit would pretty quickly run dry. Babbit bearings usually have oiler cups or auto oilers to keep a pretty constant wash of oil present. I know it is not uncommon on line shafts running in either babbit or wood bearings to be oiled every couple of hours when running under any load at all. Tough to do that with grease, I would think. Jock will be able to give you an explanation that makes more sense, probably.
   vicopper - Thursday, 08/12/04 15:09:26 EDT

See, what did I tell you? Even while I was typing.
   vicopper - Thursday, 08/12/04 15:12:02 EDT

I come before y'all with a question once more. This time, it's about stake stumps. I finished a nice one a few weeks ago (http://img.photobucket.com/albums/v239/zinguvok/2004-07-30stump1.jpg), and before I start using it in earnest I'd like to know your thoughts on banding stumps. I was thinking about taking some 1"x1/4" strap, bending it so it matches the top of the stump, brazing the ends together, heating it up with a weed-burner and hot-fitting it on. My questions are, will this work? and if swelling in the stump might be a problem, what should I quench with? Thank you all for your time.

Feeling a little inspired in Kaneohe, Hawaii.
   T. Gold - Thursday, 08/12/04 16:12:09 EDT

Bearing lubrication.
say it three times "oil is cheaper than parts"
Thanks. So by my taking out the plugged grease zerks and putting oil in the holes because I haven't gotten around to putting the grease cups into yet is a good thing!
Every once in awhile procrastination pays!
(plus CSI membership)
   JimG - Thursday, 08/12/04 16:57:19 EDT

Banding stumps.
First thing you do is make yourself a small traveller. Use it to measure the circumfrence of the stump. Measure the inside of your band. Make the band smaller in inside circumfrence by the thickness of the band. (TIP mark your traveler with an arrow and allways measure so it turns the same direction, otherwise you get two differnt lengths)Warm it up with your tiger torch, and put it on. Have a board handy to hold one side down and tap the other into place. A tire dog would be best, but if you don't have one you can get by. Iron expands about an 1/8 of an inch per foot at a high black heat, so the smaller the band the warmer you need it. Just use enough water to keep the warm band from burning the wood and let cool.
I am a wheelwright and have done a fair bit of shrinking bands and tires on.
Feel free to email me for any clarification if you need to know quicker than I can here.
   JimG - Thursday, 08/12/04 17:11:49 EDT

Banding, Step one left out by Master Jim is to let the stump dry. I have a vise in a very nice oak stump (see Vise FAQ) that I banded with an old worn piece of wagon tire (looks classy). Was a tight pounded on fit while hot. Was fun to fit since the stump was SORT of oval. Now it has a gap over 1/2". .

You may also want to soak the stump with PEG (polyethelene glycol) for a few months like wood worker's do large sections before banding. This reduces checking by reducing shrinkage. It also insect proofs the wood.

I also suspect you need to weld the band rather than braze it. I arc welded that old worn tire, dressed with a grinder then in the fire. It is hard to find the weld.
   - guru - Thursday, 08/12/04 18:45:50 EDT

Dissimilar fire welding!
I am trying to make a scroll panel with copper, bronze and steel and was wondering if it is possible to fire weld these metals together? There are areas in the design which require the three metals to come together in a point, so obviously collars would be out of the question. Any help anyone can offer will be gratefully recieved
   Andi - Thursday, 08/12/04 18:57:49 EDT

Andi look into brazing or silver brazing that joint. Welding temp of steel is generally above the melting temp of the other two metals you mentioned.

   Thomas P - Thursday, 08/12/04 19:04:37 EDT

Oiling plain bearings,
A babbit bearing, or bronze sleeve is a plain bearing, and depends on the viscosity of the oil, and the shaft rotational speed to cause hydrodynamic floatation of the shaft. This means simply that the shaft floats on the oil, and does not touch the bearing, except when the load exceeds the design point for that shaft od,bearing width, speed, and oil viscosity.The will also be contact when the speed is below the rpm required to float the shaft. These are known as PV values. Look in the Machineries and there are tables that will explain in great detail. To simplfy, for a given shaft and speed, a given load will specify the oil viscosity, or you can pick any one variable and then define the others.

In the plain bearings on an upsetter, that rotate at very slow speeds at full speed, and start/stop on every cycle, the crank bearings are about 24" id, by 12" wide, one per side, and the load is in the 1800 ton range. The oil required is EP-460. The oil used in most car rear ends is in the EP-100 range. This oil is so thick that it is easy to shovel it at 20F. This oil is pumped into the bearings at about 1500psi, by a auto oiler, and leaks out the other side of the bearings. This has the useful effect of flushing scale etc from the bearings. Grease tends to hold in the scale and does not seem to flush the bearings. In three shift operation, a typical large upsetter will consume about 200 gallons a week.
Grease is oil that has been thickned by sappranated into a soap. There are many bases such as lithium, aluminum etc. These bases are often not compatible and will cause greases to either turn to hard gum or run like water.

Since a bearing change takes about 6 weeks, a 10 ton crane, and maybe $100K "OIL IS CHEAP", is Good advice. For oiling a LG, I would seek a good oil jobber and ask for a EP type oil in the correct viscosity. The EP stands for extreme pressure, and is formulated for exactly what a LG needs.
   ptree - Thursday, 08/12/04 19:37:32 EDT

I was thinking of brazing it because I don't yet know how to torch-weld and I don't have access to a welder just yet. Also I've heard somewhere that brazing is stronger in shear than welding. Don't know. What do you say?
   T. Gold - Thursday, 08/12/04 19:39:41 EDT

thank you tomas
i was already aware it doesnt produce a hamon but it is a much easier method than the clay one. why is it not a good idea to harden and then temper at a later date? does it cause serios problems with blade quality? i would have the heat treating place do it but they will probly only do monotempering i want to have a fully hardened edge. what about cyrotempering i know a place that does it. does it rid the blade of any edge holding hardness? will it be sufficent to not have to heat temper the back?
i was also wondering if anyone knew how hard l6 steel can be heat treated to 60rc maybe? i know it makes exelent swords and band saw blades
   matt - Thursday, 08/12/04 20:06:47 EDT

thanks guru i didnt see your post
   matt - Thursday, 08/12/04 20:11:11 EDT

awp yes i know i made a mistake typing sorry about that
   matt - Thursday, 08/12/04 20:12:38 EDT

Guru, Am making a ton of c-scrolls for a handrail. Do you know of a a shape for tongs that is effective for holding the first side scroll when forging the second side? The scrolls are being made from 1 X 3/8 flatbar with a tapered ball-end. Thanks, Tim

The Forgeworks
450 W.Atlantic
Alameda, Ca. 94501
shop: 510 814 0559
   Tim Cisneros - Thursday, 08/12/04 21:25:19 EDT

I am confused. I don't understand how a tire can expand 1/8" per foot at a black heat. I understand that Jim is a wheelwright and undoubtedly knows way more than me about these things, but the coefficient of linear expansion of steel is only about .0000065 per F. Given a rise of 800 between room temp and a black heat, that only comes to about .0055, or a little over 1/2 of 1%. That should only be about .065" per foot, not .125"/ft. Where am I going wrong with this?
   vicopper - Thursday, 08/12/04 23:06:03 EDT

Matt - What cryotempering will/should do is transform any retained austenite from quenching into martensite. It may also refine the carbide size. You'll still need to temper after "crotempering". Industry terms aren't standard yet - I'm more comfortable calling it cryogenic treatment, because it's not really a tempering operation. Also, you temper soon after quenching because martensite is very brittle and the transformation creates a lot of stress. Large parts can have enough stress from quenching that if not relieved by tempering they will catostrophically explode. (Yes, I saw the results (heard the break) from a 1 + ton steel ring that production fogot to temper and let sit for more than a day - 4 pieces about 5 to 6 feet from where they started. Always temper after hardening - the one exception would be if you continue to cool cryogenically - after the cryogenic cycle is complete - TEMPER!
   - Gavainh - Thursday, 08/12/04 23:23:57 EDT

Metal expansion,
the two key words in there are ABOUT and HIGH BLACK. In my shop a high black heat is about 1000F, where it will show dull red in low light, but won't show colour in well lit. And the about part is from my teacher who told us that. It works and I've never bothered to do the math. It's just a rule of thumb that works for me. When I band a hub, or something small I do take it to a higher heat to compensate for having less stock, but it does work.
I've seen wagon tires that have a 1/4 inch gap tween the felloe and tire when it drops on shrink everything tight. The only nicer sound than a wheel tightening up is the sound of hot collars cooling. (or the neighbour saying he brought beer)
   JimG - Thursday, 08/12/04 23:42:53 EDT

wow i didnt know steel would explode from not tempering. i thought cyrogenic treatment helped relieve stress, and thats why they do it to hardened metal, but i guess i was wrong. the only reason i suggested it for my blade was because 1 of the last legend swords called the tsunami katana won the cutting compatition for 2002 and it was cyrotreated.
   matt - Thursday, 08/12/04 23:45:27 EDT

matt: Exploding is possible, though that's a worst case scenario. More likely is that it will just crack, though that's almost as bad. What you can do when you send it out is ask for a "snap" temper so you can temper it yourself. That's a temper at lower then typical heat, and what it does is relieve the stress while having almost no effect on hardness.
   AwP - Friday, 08/13/04 01:49:02 EDT

On cryo treat... Gavainh described the scientific side of what happens, you might not know what transforming the retained austenite to martensite actually does for you in practical terms. By making more martensite, you should achieve approx 1/2 - 1 extra point of Rc hardness. Something to concider with your tempering plan, the original Japanese katanas that weren't tempered were generally roughly equivilent to 1050-1070, nothing like L6.
   AwP - Friday, 08/13/04 01:57:01 EDT

Best Tongs: Tim, I am not sure how you are handling these but the goosneck bolt tongs I modified as shown in my iForge Froe demo works very well on flat bar. I also like side offset tongs for reaching past scrolls. A combination of the two forms would be the handiest shape I can think of for what you are doing without being in your shop to see. .
   - guru - Friday, 08/13/04 02:05:31 EDT

What do those giant upsetters look like? How do they work?
T Gold;
Brazing looks like your only choice. Doubt it has a stronger shear strength than a good weld but it is quite versitile and if your prep is good, reasonably strong.
HEY! YOU! GUILTY LURKER! JOIN the CSI! or your welds won't take!
   - Pete F - Friday, 08/13/04 02:48:51 EDT

Pete, I'm trying to figure out if I am a Greasy Lurker or a Guilty Lurker. Can you help? Tim
   Tim Cisneros - Friday, 08/13/04 09:37:06 EDT

FRIDAY the 13th Well. . . we are finally back on-line. We dodged a big bullet today. The server hard drive crashed during the backup this morning. It was restarted and the backup finished. After the new drive was installed it took a couple hours to get the counters, databases and secure certs up and working. As far as I can tell all is OK again.
   - guru - Friday, 08/13/04 10:38:56 EDT

tim cisneros, i recently modified a "tong" to do exactly what you are interested in. i could e-mail you some pics and what the c scrolls look like, if you want..
   rugg - Friday, 08/13/04 10:55:20 EDT

Upsetters: Pete, BIG! They are one of the heaviest and most complicated machines in the forging industry.

They operate horizontaly and take up a roughly rectangular space. Small upsetters are the size and shape of a mini-van and big ones the size of a couple 40 foot tractor trailers parked side by side. They are close to a solid mass of cast iron and steel so they are VERY massive and VERY heavy. Small ones weigh 10 to 20 tons. Big ones? I could only guess but the number would be incomprehesible. Like asking what does a mountain weigh.

Most upsetters have a crank opperated ram that does the squeezing. They are sort of like a horizontal punch press on steroids. Then they have a hydraulic clamping system to hold the hot bar in dies while being mashed. Everything is sychronized mechanicaly and is quite complicated.

They are also part of the sad story of the failure of the American primary metals industry. They are a very important machine industrialy. Like big forging hammers, they are no longer made in America. Old ones are repaired and rebuilt. Fewer and fewer are in use in the US. Many are being shipped overseas. But they are no longer made here. And we once made the best.

If our government doesn't wake up to the real industrial disaster that is happening in this country those of us that run small blacksmith shops with hand tools and small power hammers will be the only people forging steel here.
   - guru - Friday, 08/13/04 11:00:05 EDT

good evening guru
I was in a glass works today and I managed to have a look around the stores the chief fitter showed me some of there refractory materials and they had durablanket they also had a product called wet blanket it came in 3 feet by 2feet packets he said that it was soaked in a ridgidiser that would air harden then when fired it would go hard and dense i also got some blanket but could not get itc 100 i will get it from anvilfire could you tell me if anyone has tried this wet blanket thanks david
   david hannah - Friday, 08/13/04 13:36:43 EDT

hello again i was looking for away to make acorns and scotch thistles in the fly press with a set of dies or would they have to be done by hand thanks david
   david hannah - Friday, 08/13/04 13:47:55 EDT

Brazing vs. arc welding - A thing to consider: E-7018, considered a very good welding rod, has a tensile strength of 70,000 psi. Welco 200 silver brazing rod has a tensile of 85,000 psi. Common brass brazing rod has a tensile strength of around 50,000 psi. Brazing prefers lap joints over butt joints.

Matt and your supersword: Do some research on heat treatment, including the FAQ here. Cryo treatment does nothing at all to relieve stress, if anything it increases it. All it is is a continuation of the hardening process started during the initial quench from above 1600 degrees F or thereabouts. Quenching brings steel to its maximum attainable hardness, and consequently its maximum brittleness. Tempering, the process of reheating a small amount, relieves some stresses, with a consequent lowering of hardness, but gains you some toughness. Until you have a very good working understanding of what heat treating does you have no business attempting a sword.

I am fussing for your own safety and that of those around you. I've had a factory-tempered machete blade break while cutting brush, with the six inches of broken end sailing about two inches past the left ear of one of my co-workers before coming to rest about thirty feet past him. In steel that is too hard, the slightest crack or chip will propagate catastrophically, aka explode. Made a neat high-pitched ring as it whizzed by John's head, though.
   Alan-L - Friday, 08/13/04 14:12:13 EDT

Keep having a "Shrinkage?" hole in my bronze castings right where the main sprue attaches to the piece.
Also have "cross hatching' on flat surfaces sometimes.
Have tryed casting at diff. temps from 1950 to 2100.
What am I doing wrong?
   Glenn Schot - Friday, 08/13/04 14:16:55 EDT

Glen, I would think you need a larger sprue and possibly riser. Aside from the function of being a way to get the metal in the mold, it serves as a reservoir of metal to fill in shrinkage. If they solidify before the casting, there is nothing left to fill the shrinkage of the metal cooling. This would also get the metal in the mold faster giving the metal less of a chance to freeze on the flat sections. Just my 2 cents.
   - Wayne Parris - Friday, 08/13/04 15:40:33 EDT

Guru: I have a WWII? vintage blower I have had for many years. It is a combination of stamped and cast parts with no factory markings,serial numbers etc. It was painted navy gray on the outside an o.d. green inside the fan housing. It's a great blower though I haven't used it in years. Any idea who made it? Also I have an old cast steel?
sawmakers anvil with no markings on it. It weighs about 110 lbs, a good flat face with the usual chipping around the edges, and has four cornered feet just like most common anvils. Any info as to who might have made it and its value?
My compliments once again, to you for one of the best information sites on the web. I wish this had been here 20 years ago when I started smithing.
   RC - Friday, 08/13/04 15:42:33 EDT

David Hannah:
That blanket is most likely Kaowool or something similar soaked in colloidal silica. I've never seen this sold as a regular product, but it's very easy to make and work with.

Thanks for the info. My thinking based on what I had heard was running along similar lines. I will go with the braze for a wide variety of reasons.

The trade winds are blowing in sunny Hawaii.
   T. Gold - Friday, 08/13/04 16:48:43 EDT

Glenns Casting ProblemCasting Problem: Glenn, we need a slightly better description of the part. However, as Wayne pointed out the metal in the sprue or riser must replace the metal in the interior of the casting as it cools and solidifies. There is a considerable volume difference between cold metal and liquid metal. If the part shown is solid or has thick walls the sprue is entirely too small.

In many cases especialy where you have large solid sections the volume of the risers must be nearly equal to the volume of the casting. In small castings the sprue doubles as riser. In large castings the risers are seperate and fill from the casting.

The metal cools from thin to thick. So the risers are idealy compact and more massive than the sections of the casting. As the casting freezes it draws metal from the sprue and riser. If the sprue is small and the risers large the gates to the risers must be larger than to the sprue so that they stay clear until the casting finishes freezing.

Where you have vents these can sometimes double as risers. However vents such as yours on small protrusions need to be vents and the feed risers somewhere else.

One caution about vents and risers. They should not increase the total casting in height too much. The increased height increases the pressure in the mold which increases possible penetration into the sand.

Gating an risering castings is a true art. There are some basic rules but in the end it is based on experiance and trial and error.

I am not sure about what you are calling cross hatching. There are millions of casting surface defects that can occur. I'e seen dozens on ONE casting. They can be caused by dirty metal (mixed scrap and bad alloying), insuficent refractoryness of the mold material, penetation into the sand, burned plaster, insufficient riser . . .

Surface problems occur most often on the top of castings where dross and air collect in the mold. These top surface problems are avoided by casting the part upside down, added vents and by large risers. Filling the large risers through the part helps flush dross and air out of the mold.

The heavier the casting sections the more refractory the mold material must be. This too can be an art. Where a jeweler uses sand that is powder fine, a machine tool caster must use coarse sand that is nearly fine gravel. Things that work at one scale will not work at another.

We have some others that are more experianced in casting than I and they may also chime in.
   - guru - Friday, 08/13/04 16:58:21 EDT

The above points out a common error. A foundry that can melt XX pounds of metal cannot make XX pound castings. The heavier the casting cross section the lower the ratio of the casting size. In thick heavy castings this is as low as 50%. So a foundry that can melt x pounds of metal can only make ONE x/2 per melt. Where the problem comes in is where the foundrymen are used to proportionaly thin castings that take little gating and risering. If you give them a thick section (like and anvil or swage block) that they are not experianced with the resulting castings will be a mess.

I had a local foundry do some swage blocks for me years ago. The first batch had floated the top of the mold and then shrunk excessivly. The sides of the block were curved IN 3/8" (10mm)! The top bowed UP 1/2" (13mm)! I rejected them and the foundryman that KNEW they were junk was upset. . . He tried a second time by opening up the gates and and adding more sprue. The castings still had more shrink than they should, there was excessive gating to cut off AND the top floated again. I accepted these castings under protest and in fear of losing my pattern if I refused them. I sold them for less than they cost to have cast.

The problem here was that the foundry KNEW how to make castings that weighed hundreds of pounds as long as the section was not over 1" (25mm) thick. But they did not know how to handle 4" (100mm) thick sections. They did not want to waste an almost equal amount of metal that went into the casting on risers. They did not have the weights or know how to properly weight the top of the mold. And their moldmaker (sand crab) did not understand gating.

I knew what the problems were but they were not going to take advice from an amature patternmaker. . .

Previously I had these same patterns cast elsewhere and the castings were perfect. But the guys that did them were used to casting huge machinery castings with sections a foot thick in places. My castings were child's play for them.
   - guru - Friday, 08/13/04 17:21:30 EDT

upsetters, Big, huge and even bigger. We are currently installing a 7 1/2" upsetter. This rating is based on the diameter that can be upset. For instance, a 2 1/4" bar, upset to have a 7 1/2" flange on the end. This does not really limit the flange od as there are tricks to get a bigger flange, but is the rating. The 1940's 7 1/2" has a bare frame that came in on a truck that was 240' long, and the frame alone weighs about 493,000#. All together, I would guess something like 750,000#.
I have to disagree with the GURU on a couple of minor items. The major makers of these machines were AJAX and NATIONAL. both still exist, although AJAX would have to farm out all manufacture. With the cost of these huge machines and the very durable nature of these jems of 1920 design, rebuilding is the usual choice. The better machines are now getting somewhat hard to find, and manufacture of new machines will no doubt restart. They may well be built overseas as the casting houses that could pour a 500,000 pound castings simply don't exist in the US anymore.
The way these machine work is that a flywheel turns a crank thru a clutch. When the clutch is pulled in, the crank turns through one revolution. This move a grip slide by a cam to grip the bar. Not hydraulic but a mechanical slide. Then the tool slide comes forward, and the bar is upset forged. Typicaly several impressions are in the tooling, with 4 or five being typical in our shop.
A 10" upsetter, can forge a 4140 bar of 6" od into a flanged shaft with a 20" flange 3.5" thick in 4 hits.
I beleive that there are maybe 2 10" upsetters in the US.
A 4" upsetter can upset a 3"od end about 3" long in a 2 1/4" bar in 1 hit, and if automated do it to a fresh bar every few seconds.
These machines while very large, are about as mechanically complex as a Little Giant, with an extra ram. The lube systems are the complex part, with perhaps 250 lube points serviced by an auto luber/sequencer.
   ptree - Friday, 08/13/04 17:22:04 EDT

Imagine the foundry that could cast the main frame for a 10"upsetter, a finish machined frame at say 750,000# So say a rough casting at 850,000#. Say 1,600,000 pour!
   ptree - Friday, 08/13/04 17:29:32 EDT

BIG indutstry: Ptree, I think Ajax is long gone. From what I understand they were bought out by Ohio Forgings (not sure of curent company name) in order that they could maintain their own machinery. They kept the name and operate and an office as Ajax to keep the appearance that they still exist. I THINK National is the same bought by the same folks. They do not make new machines. They regularly export and sell rebuilt machines.

But this is like saying that Sid Sudimeier makes Little Giants or IS Little Giant. Both have the same problem that there is a finite number of machines to rebuild and repair and they do not have the expertise to design and build new machines. Nor do they have the demand OR capital to recreate a huge industry.

Chambersburg Engineering company was in the same state for a long while. Rebuilding and servicing old machines but not making new. Ohio Forgings tried to buy them out for the same purpose. However, deals failed with greed playing a part, and the company was sold piecemeal at auction. Overnight they were gone. A group now sells copies of the old drawings for outrageous prices but does nothing else.

As you said. We no longer have the capacity to make certain large castings. Other parts of our industrial base have also suffered. In four years from when Three Mile Island occured all the machinery necessary to build large nuclear power plant pressure vessles were dismantled and sold overseas. The vertical turret lathe that B&W had taken 10 years to have built and installed that was the ONLY machine capable of machining the largest vessles was one of these. 10 years to create and install, 1 year to remove and export. The foundries to make the castings to be machined on that tool are also gone. B&W also made the world's largest pipe that was used for, among other things huge mining machines, not just nuclear power plants.

Small technologies are also lost. I tried to find someone at the Thermit Company to discuss welding a large section (anvil waists). It took many phone calls before I found someone who could respond. They said they no longer have any engineers on staff and are not making new products. They are just making a few of the old servicing the railroads. Large foundries used to be a big part of their business but no more.

The folks that cast those swage blocks for me in the 1980's also cast six ton machine tool frames for us with 4" walls. Small in comparison to upsetters. But they supported many other industries. They are now gone and so are the folks that machined the parts.

How long does it take to recreate a complex interrelated industrial base? . . During WWI we built plants in 3 years that now takes 12. We have not only lost the physical industries but the skilled people necessary to build these large projects. IF we ran out of oil today and decided to switch to nuclear as the only short term solution it would take 30 years to get where we were in the late 1970's.

That is a long time to go without lights. . .
   - guru - Friday, 08/13/04 18:08:32 EDT

Ajax is a few people selling service. National is still running a shop and rebuilding machines. I beleive they will make a new one, but the castings at least will be made outsource.
   ptree - Friday, 08/13/04 18:28:44 EDT

Peter- if you go to hoffmanmachinery.com, and click on upsetters, there is a whole page of pictures and specs on these big boys.
Everything from a nice little 1" ajax, which weighs a mere 18,000 lbs , to a 7", which is giant in like new condition, stored since 1952. This dealer also has a bunch of other interesting huge forging machines, including a lot of machines that are sitting idle in eastern europe, but for sale here. The former Iron Curtain countries evidently have a lot of factories that are sitting empty now, and the equipment is available.
   - Ries - Friday, 08/13/04 18:54:34 EDT

We have a 4" up to a 10". Now installing a 7 1/2", and another 9". Lots of interesting forgings to choose from for taking home! Almost every flange starts as a cone, then a steeper cone. i have a 454# flanged shaft that I intend to use for a JYH anvil. 6" shaft, out of 4140.
   ptree - Friday, 08/13/04 19:57:38 EDT

Glenn Schott,

For the problem of a hollowed-out sprue cup, you need to think in terms of much more metal. Your casting is pulling in more metal, as it cools, than your sprue can supply. To overcome this problem, I often make a "ball" just below the sprue cup, at thge beginning of the main sprue. The ball is the best shape for lowest volume to surface area ration, thus keeping the metal molten as long as possible. Don't be chintzy when making that ball, either. Almost as big in diameter as the big end of the sprue cup wouldn't be very excessive.

When your casting is pulling that much metal from the sprue cup, it says that you do have adequate gating and risers, generally speaking. If your gates and risers were grossly inadequate, then the model would be unable to pull the metal from the sprue cup.

the "cross-hatching" you refer to sounds like what I call alligator skin. It results form the metal shrinking away from the surface of the mold while still molten in the core areas. This causes the surface, which has "set", to wrinkle in slightly as the core cools and shrinks. There are two suggested remedies for this. (Or three, if you're not using high quality investment the has adequate porosity.)

Increasing your sprue cup volume will help to keep the shrinkage filled from the sprue rather than pulling away from the mold cavity walls, providing that your gates are adequately sized. Mot of the time, this is all you need to do. In some cases, this can occur due to the investment not being hot enough before the pour commences, which causes the metal to "freeze" at the surfaces of the model when it comes into contact with the lower temperature of the investment. Usually, this will occur with other problems of worse magnitude. Since you didn't mention any other problems, I doubt this is the cause of the cross hatching. I really think that increasing your reservoir of molten metal will solve both your problems.
   vicopper - Friday, 08/13/04 20:24:34 EDT


WWII blower: Buffalo made a bunch of hand blowers to help ventilate bunkers and bomb shelters. They were well made and capable of pushing a lot of air so should be good for a forge.
   - HWooldridge - Friday, 08/13/04 21:21:02 EDT

alan l.
i understand heat treating quite well actually. i have made short swords in the past and many knives. i just never attemted as a japanese katana before. most of the swords ive made are broad swords. i have done plenty of research on the subject of heat treating, and the place that told me about the cyro tuning was a legitamate heat treating buisness. ive never had a problem with any of my swords breaking or chipping. i have never seriosly injured myself with anything i have made or used. maybe the machete you had had a factory defect or was badly made with poor workmanship or materials? you cannot judge a factory made machete to a handcrafted sword. sword have a totaly diffrent purpose than machetes. swords are tempered more than a machete to gain toughness as you said, i know this, unless its a japanese katana which is a whole diffrent story. i make swords, knives, and armor as a hobby, and to sell to local shops at the medival faires. my blades have been tested on armor and simulated soft targets and work very well. im not one of the niave beginners you get on this type of forum. i just was starting a new type of sword from a new steel i havent used before and was asking for advice. also i have no idea why you had to use the words "matt and your supersword" you make me feel like a novice with those words, which i am not.
i mean no offense to you i just wanted to give more info about myself so every one here doesnt mistake me for a stupid kid with no matal working skills wanting to make a "sord".
   matt - Friday, 08/13/04 21:31:48 EDT


Nor was Alan L. trying to make you feel like a naive beginner. He was just concerned about your safety, and not knowing your level of experience was justified in cautioning you.

One of the problems with the two dimensional medium that we communicate with over the Internet is the lack of visual clues. We can't see the grin on a person's face, or the concern in his/her eyes. Reading your message, we can't tell if you are fourteen or forty. That lack of information is sometimes a cause for serious misunderstanding.
   Paw Paw - Friday, 08/13/04 21:47:12 EDT

From Glenn Schot,
Thanks tons Guru, Vicopper and Wayne! I think you hit the nail on the head! Not enough in the cup. The first casting I made came out better (Less of a hole) because it had a longer sq. 3/4" sprue and I filled the cup
up a bit more. I thought I would be correcting the problem by less metal in the cup and saw that it made the problem worse. What you said really makes sense now I will try
casting with cup totally full. After I fix my melting furnace X*#?#@.Been finding out the hard way about 240 V electric coils. Am going to order heavier #12 guage with
lower coil dia. Kantal or NiCrome. I've been hanging them on wall of furnace with SS pins. Found thinner guage / large dia. coils sagged and burnt out a lot. Going for #12
guage narrow dia. coils - 2 seperate curcuits -15 amp 240 V each in my little 13"dia. x 11" H furnace. Might replace "Electric Range " controls with straight 20 amp/240 V
toggle switch cause I just turn it off anyway when I hit "Temp". What do you think?
   Glenn Schot - Friday, 08/13/04 22:55:08 EDT


You're on target with the modifications to the furnace. The larger diameter wire will have a lower resistance, of course, so you have to work out the appropriate length to get the correct ohms/foot to yield the temperature and current draw you need. If I recall correctly, Paragon Kilns has some decent info on their website, as does the company who makes Kanthal alloy.

One reason to stick with the proportional controls is to maintain an optimal temperature of the coils themselves, to minimize oxidation and deterioration. I'd try it both ways and see which works out best. Let us know how it works out for you.
   vicopper - Friday, 08/13/04 23:45:04 EDT

OR you can build a little propane melting furnace. About 10 minutes from firing up to having 5 pounds of liquid brass . . .
   - guru - Saturday, 08/14/04 00:38:46 EDT

you got that right paw paw thats the worst thing with forums, and thanks alan for being concerned, but like i said im always safe with the swords and knives i make. each 1 goes thru extensive testing to make sure it works before i sell it. expescially the mock battle swords with blunt edges for reeanactment.
   matt - Saturday, 08/14/04 00:46:11 EDT

and in case anyone is wondering i am 16. and many blacksmiths think that because of my age i cannot be a very good smith yet, and like on the gen x swordmaking page it says bladesmithing is at the top of the ladder for blacksmiths, but there are considerations to be made. the reason i can make quality swords and knives is because my grandpa was a machinist and a blacksmith and taught me at an early age how to forge and then once i was good at general smithing he taught me knife making, and i expanded on my own with some of his help, and help from books into swordsmithing. obviusly i dont know everything im still learning an incredible amount everyday. and lately ive been leaning twards japanese sword smithing and polishing which takes 20 years to learn. i find the need for so much disipline in japanese sword smithing interesting, and so ive been trying out my new japanese sword forge trying to produce a very high quality blade. and anyone with advice to give would be quite usefull
   matt - Saturday, 08/14/04 01:04:15 EDT

Hey Tim:
Last seen, you weren't anywhere near greasy enough to qualify...so , If by some accident you havnt yet joined CSI to help support Anvilfire, then the guilt must be yours.
3 big cheers for our stalwart GURU.
Agreed; Abandonment of our heavy industrial infrastructure is a disaster in terms of defence.
Thanks ptree: 1,600,000 #pour! Spit-oh-dear! Huge doesn't describe it! Now THAT justifies use of the word...Awesome!
   - Pete F - Saturday, 08/14/04 03:17:17 EDT


Though we do get a bit impatient with the "i wanne mek a sooord" crowd, we are not hung up on the young crowd. One of our regular contributors is (IIRC) 13. He started banging metal when he was 6 years old, has been demontrating publicly for 4 or 5 years old, and has several demonstration in the iForge Section. Matt, meet Whitsmith! (grin)
   Paw Paw - Saturday, 08/14/04 08:12:44 EDT

Matt, Please accept my apologies, I was just trying to make the point about improper heat treat being a dangerous thing. The machete was a factory flawed piece, which I mentioned just as an example of things that can go wrong. The fact that even professional heat treaters sometimes use the wrong terms for what they are doing doesn't help us any, eh? (big grin!) I wish you success with your undertaking.

Now then: for some really good but very technical advise on heat-treating blades, have you tried the forums at knifenetwork.com and dfoggknives.com? Advise from real pros, and generally nicer than swordforums. Not that there may not be someone here who can help you, but I've found these other resources good as well.

Incidentally, I'm 35 and have been outsmithed by a few younger guys (grin). If I had started younger than I did (27?) it would have helped!
   Alan-L - Saturday, 08/14/04 08:36:46 EDT

The Gurus continued observations on the flight of industry from N. America is right on the mark. I have personel experience with the loss of a 125 year old company that was broken up, and technology, equipment, expertiese, etc. being lost to America. The company I worked for made the best, and most widely varied line of valves and fittings, boilers for the power generation trade, ice making equipment, and forgings in the entire world. The valve and fittings biz went to India. the boiler biz went to the Dutch/Germans. The forging biz stayed put but very deminished. The ice making equipment biz stayed put and is still strong. The valve and fitting biz supplied the paper and pulp, waste water, chemical, refinery, power generation and nuclear people, including our own Navy. Thats gone! Note carefully that those industries are the backbone of our civilazation! Gone!
There are many reasons that heavy industry is flying away. Some blame environmental regulations. We have to balence industries needs with a clean environment. We can not continue to crap in our own nest. Some blame unions and the desire for too high wages/benefits. Thats crap!The American worker is still the most productive worker in the world. Look it up. I blame the onset of the wiz kid management school type. They look at a quarter of a year as long term. They make decisions based on the next stock report. Not next year, not next decade. They don't own the biz, and don't intend to stay and grow with a biz. They look at next weeks salery, and will jump ship for $2.00.
I don't have an answer, but when we have tax laws that encourage offshoring, we are cutting our own throat.
   ptree - Saturday, 08/14/04 10:00:59 EDT

Some of the last advise I got from My Dad was unless you no longer have a wall to have your back against don't sell tools,
And then think real long and hard before you do.
Looks like this applies on a larger scale too.
   JimG - Saturday, 08/14/04 11:15:43 EDT

Something Wicked This Way Comes

My brother rode out Charley in the Floriday Keys, but the gulf coast got clobbered. I's supposed to be anly a tropical storm ad about 50 kts. by the time it gets here, but I'm battening down anyway. All it takes si a tree limb in the wrong place and your withoiut powere or teying to fix a broken window with the rain blowing in.

Y'all take care out there, and keep your heads down; I'm off to the barns next.

Vist your national Parks (but not Everglades right now): www.nps.gov

Go viking: www.longshipco.org
   Bruce Blackistone (Atli) - Saturday, 08/14/04 12:12:16 EDT

Thanks for keeping a weather out for us Capn' Atli!
   - guru - Saturday, 08/14/04 13:34:20 EDT

I recently acquired some cast iron parts that appear to be part of an old forge (or maybe just an old furnace??). I would appreciate any information anyone can provide or suggestions where I might be able to find a picture.
The bottom piece appears to be the air chamber that a bellows would attach to. It is about 32" in diameter with a neck on one side that is bout 4" long and 7" in diameter that would allow air to be pumped into a 12" wide & 12" deep fire bowl in the center with an outside ring which would allow air to go out a neck on the opposite side that is about 7" long and 7" in diameter. It has the numbers 36 and 30 stamped on one neck.
The piece that sits on top of that is a 22" wide and 14" deep fire bowl with an opening extending out on the front to access the fire. This looks like it might have had a door on the front.
The next two pieces that sit on top of that are shaped like a large tire rim neck. They are each about 22" in diameter and 6" high. The one that goes on top has slots molded around the inside about 5" apart.
Next is a piece about 22" in diameter and 12" high with an opening extending out the front similar to the fire bowl. This has a hook in the opening but it is attached on the bottom rather than on the top if I have them stacked correctly.
The last piece is a flat piece cut to fit on the top and enclose the stacked pieces.
Stacked together, it is approx. 5 feet tall.
I also have a metal hood that has a rectangular opening on one side about 18"x24" and a round opening on the other side about 12" in diameter.
I would appreciate any information you can provide.
   Wendell Memmott - Saturday, 08/14/04 13:59:30 EDT

Wendell, It does not sound like a forge or even a melting furnace. You may send me digital photos but I have doubts that we can identify it for you.

Going Offshore: Taxes, regulations, costs of doing business are all factors. Short sighted accounting practices and the American stock market are a HUGE factor.

One of the big changes that happened was that managers started seeing employees as a "cost center" rather than a "profit center" in accounting terms. Rather than looking at the fact that an employee or even a manufacturing plant OR a resturant was making a profit or not stopped being important. Only the expenses were compared to other individuals and locations. If the costs were higher the profit was not considered. Employees are laid off, plants shut down, businesses closed that were ALL making a profit.

Stock market valuations are also illogical. In the 1980's the market wizzards realized that almost every business that had stock in the stock market could be bought for much less that the company was worth just by buying the stocks. These people became known as corporate raiders, buying up companies and disposing of the physical assets for a profit. TENS of THOUSANDS of productive profitable companies were destroyed by these acts of greed. People that complained were told "you don't understand the market". This was the same as Bill Gates telling congress that "you don't understand the computer business" in defense of his monopoly which he still has and is destructive to the overall industry.

As much as I hate the exportation of businesses off shore I am looking at doing the same personaly. I can live better, pay less taxes, afford health care. . .

But if I had a manufacturing business I would be crazy to move off-shore. We still have the BEST business infrastructure in the world. Almost everything and anything can be obtained on short notice with little aggrevation. But this is changing. As big manufacturing leaves the small manufacturers and wharehousing that support them fail. We become a poorer nation while others become richer.

A strong ecomomy starts with certain primary industries. Mining, metals, energy, transportation, food production . . . Ignoring the metals industries results in failure of the others. All countries need long range ecomomic planning. Ours is currently based on politicians buying votes and the stock market making short term profits. Eventually it will catch up with us.

How does this apply to Blacksmithing? You NEED those small suppliers that service big industry. Those are the people you buy your steel, rivets, nuts, bolts and tools from. Those are the people that make a wonderful machine like the Big BLU or the Phoenix hammer possible to build economicaly in America. WE need the big industry so that our small industries can exist. It is all part of a whole.

--- The unknown candidate
   - guru - Saturday, 08/14/04 14:16:50 EDT

Yet when the 2719 Group needed a new 75 inch driver for their steam locomotive they were able to find someone in St. Louis to cast them a new one. It was done using lost foam and they got a better job then the original.
   - Hudson - Saturday, 08/14/04 14:40:18 EDT

Hi, I just found this forum on a search of Norwegian Blacksmiths. My ancestors were well known blacksmiths in Voss Norway in the 1800's. I am in contact with other researchers with Norwegian blacksmith family of the 1800's that emigrated here in the early 1800's. We are all looking for books or sources on this subject. Any Idea where we might go with this search?

I dookmarked this site and will check back. Any helful info can be sent to my address ask4@mchsi.com just in case.

Al Askevold
SW Missouri
   Al - Saturday, 08/14/04 16:22:54 EDT

Something wicked..


We're in the eye right now (Sunny, calm clouds to the East and West moving in different directions), and it looks like Charley has lost much of its oomph. Winds gusted up around 40mph, but the steady winds probably never went above 10. Lots and lots of rain though. Hopefully, by the time it reaches you, it'll be reduced to a mild summer shower. (grin)

   eander4 - Saturday, 08/14/04 17:07:46 EDT

Hudson, The US still has the largest industrial base in the world. But it is shrinking at an alarming rate. While we are deindustrializing countries like China are industrializing as fast as their economy shear will of numbers will allow.

By shear numbers countries like China have the capacity to make us a minor palyer economicaly if we do not reverse the current trends here.

I recently heard a disturbing statistic. There are more English speakers in China than in North America. But try to FIND those English speakers when you need one! That is just a small example of the scale of the giant we are facing. The misguided economics of the mid 20th century set China back a century. But they are making up ground FAST. When you have a population of Billions as apposed to a few hundred million a LOT can be done the hard way and temondous advances made in a short time.
   - guru - Saturday, 08/14/04 17:38:25 EDT

Hello Guru,

I have a deep interest in blacksmithing. I have read the FAQs and plan on buying whichever books I can find from the suggested lists you've given. My question isn't how to start or where to start becoming a blacksmith, but I wanted to know how many years approx. it would take to become a fully funciontiong blacksmith? I realize that you never stop learning, I was just curious how long it takes to get to the level of mastery you've attained. I'm 22 presently, and have been searching for a trade that suits my tastes... and blacksmithing intrigues me and holds my interest very well. I love the idea of being capable of so many feats and being able to craft so many things that are actually worth using. Plus I like fire... :D

Any input, suggestions, advice, anything of the sort to help me better understand the perils you've gone through would be greatly appreciated and respected as I begin my journey into your world.
   RoachBurn - Saturday, 08/14/04 22:35:32 EDT

I had a business that failed due in large part to offshore competition. 300 people in 3 states - out of business... The banks would not work with us, nor would the vendors. They all said that injection molding was going offshore so there was no reason to keep struggling. Easier for them to just fold the tent and go home. The customers we had were very loyal but that was not enough. My biggest problem with the whole thing is that every single thing that is mass produced is made with some kind of tool and a whole generation of toolmakers is being lost. I was in the business 20 years and never saw the volume of shops closing down that I saw starting around 1999 and proceeding to the present. In 1998, Compaq and Dell were in production here - that is now all overseas, along with the suppliers and subcontractors that supported them. All the infrastructure is leaving the US and we have lost or are rapidly losing the ability to make things.
   - HWooldridge - Saturday, 08/14/04 23:31:39 EDT

Roachburn, how much time will you be putting in to this per day? Will you be working with other better smiths? or by yourself? Do you learn well by yourself or not? I have seen some learn so rapidly it scares me and others so slow I just want to cry..... so it all depends on your natual ablitly and aptitude, your willingness to work at it and how much time you can devote to it.

Best advice I can give is try to find a local smithing group and attend meetings. And attend hammer-ins. Both for the social aspect but also for the learning.
   Ralph - Sunday, 08/15/04 00:06:03 EDT

Been a while. Where does the time go? Power hammer build has advanced to the point that I need to think about dies. I have a material available called A-2. This is air hardening tool steel??? Correct?. Will this work for dies? Woll there be a problem weldind it to the mild steel plate I plan to use for mount plates?. Or should I look at another material? I have a big chunk of rr rail that I have earmarked for dies. Thanks in advance for any and all input. Dodge
   Dodge - Sunday, 08/15/04 01:35:26 EDT

I'll second Ralph's good advice.
Most smiths won't be able to approach the good Guru's level of expertese in their lifetimes...except in a few specialized areas.
It's a question of talent, smarts, ambition, physical ability and general level of output. A modicum of pyromania helps.
Go to all the blacksmithing meets you can..they are a fast, cheap and intense education if you take good advantage of them. Read like crazy and...well...play with fire a lot.
   - Pete F - Sunday, 08/15/04 02:04:50 EDT

A2 Dies: Dodge, Tom Troszak of Bull hammers, now Phoenix hammers welded H-13 to mild steel plates. The parts had to be preheated quite hot and were welded with something called "super missle" rod (a former trade name). This was very expensive rod designed for welding tool steels. It was over a dollar a stick.

A-2 is very easy to heat treat. I seal parts in a stainless foil bag, heat to nonmagnetic in a gas forge, remove and strip off the stainless foil with the part on a rack to cool. A gentle breeze is better than still air. When the part is almost cool enough to handle with gloves I put it back in the front of forge which has been cooling since removal of the part. I have a thermo-couple to measure the forge temperature and put the part in when it has cooled to about 450°F. The part reaches about 400°F to temper. Higher temperatures would be better for hammer dies.

   - guru - Sunday, 08/15/04 02:43:28 EDT

alan, i hear ya. i know tons of freinds that do bladesmithing, more like primative bladesmithing, because the knives they make are very rough. basically they finish with a grinder, no polishing. but they are still very seviceable. i think the reason for this is there is many exsmiths in the area who get their grandchildren intested in smithing.
my bladesmithing intrest(not skill, that came from my gradpa) came from a book called indian handcrafts this book had a 4 page knifemaking section on tradeknives there was multiple methods but the 1 i choose was the 1 using an old file. it said heat the file cherry red, cool it slowly with air, then grind to shape. then it gave a simple heat treat process. i still have the knive and wear it hunting. i did find a problem with it though that i fixed. the writer forgot to put in the hardening process and whent strait to tempering. so basically it tells the reader to temper an annealed blade! maybe you could put a step by step file/knife making on the gen x page? just to tell begginers how to make a stockground knife from a file. i think it would content alot of the "i wanna make a sord" types.
alan, its cool i should appoligize too, thanks for the refrences, im already a member of bladeforums.com, but im planning on joining dfoggknives.com i didnt know they had a forum or i would have joined it, i love his work.
GURU,is it possible for me to make a saltbath heat treater, sorry i dont know the proper term, i do have limited money, and i dont know what they are heated with. could i fill my sword quenching pipe with salt and put it in my forge?(the quench pipe is just a 2" steel pipe caped off on the end.) as you can probly tell i have no knowledge of these saltbath tanks.
thanks for helping alan,guru,and paw paw
   matt - Sunday, 08/15/04 02:58:03 EDT

Learning: RoachBurn, The time nesessary to learn any job well depends on many factors. There is also the question of how you define the job. The title "blacksmith" is a very broad one. To become a "master" smith with skills in hand and machine forging, tool and die making by hand, heat treating, design and joinery covering decorative and industrial smithing as well as locksmithing (it used to be a standard part of becoming a Master smith) can take many years. These as well as some wheelwright work and horse shoing are all included in being the idealized pioneer Master smith. The reality was probably much less than the idealized. Most specialize, becoming decorative smiths, bladesmiths, wheelwrights. Decorative smiths can specialize in archetectural work, sculptural, furniture, hardware. Bladesmiths make large and small blades and most that are good know their limitations.

Forging skills come from time and experiance. If you work in the forge a few hours once a week you may never develop the hand skills and experiance necessary to be a competent smith. But if you work in the forge daily for at least half the day each day you may have decent forging skills in a couple months.

Most modern smiths do not attempt such a wide range of skills nor need them. On the other hand most modern smiths work in small one man shops where they do EVERYTHING themselves. This includes managing a small business and doing everything from taxes and design work to sales and production. The modern blacksmith shop also more closely resembles a machine shop than the romantic smithy. If you think you can make a living without a significant collection of machinery then you are dreaming. MIG, TIG and plasma machines are common. Machine tools including ironworkers, drill presses, lathes, milling machines and power hammers and other machines are often found in the blacksmith shop.

As an adult approaching this kind of learning task a lot depends on the skills you start with. Some people learn to use tools and to build things early in life. I had my own small set of tools and a bench vise when I was 5 years old. I was building things and doing electrical and mechanical work usualy done by licensed tradespeople in my teens. I learned some of this from my father, but I also bought books and manuals and studied them. When I started smithing I had a deep background in art and mechanics.

Smithing requires both physical and mental skills. Every task from using a file to drilling a hole requires practice, touch, and hand eye cordination. Using a three pound hammer to forge a leaf is a lot like tying your shoe laces while wearing boxing gloves. It takes many hours of practice. And not just hours pounding away. I have watched people LOSE skill by not caring or having the pride in their work to make EVERY piece as skillfully as possible.

The mental skills include knowing how to calculate the materials needed and bid a job. That geometry you thought you would never need in high school will be needed over and over to calculate volumes, weights, layouts for cones, spirals and ovals. Those bids need to be writen up and the job SOLD.

If you intend to be a decorative smith then you want to be a "artist blacksmith" or as the German translates, an artsmith. Many go into this field and never consider the fact that they were not an artist in the first place and do not have the patience to learn this as a seperate skill. To be an artist blacksmith requires drawing, design and layout skills.

A Pete pointed out, it depends on the time you put in and your desire. The vast majority of smiths love the art so much they LIVE blacksmithing. They spend every spare moment in the shop or studying anything related to the trade. They plan vacations years in advance to go to blacksmithing conferences to wacth other smiths OR to go to schools to study under the great masters of our time. They scour antique shops and flea markets for tools even when they have shops so packed they cannot get in the door.

That was the long answer. The short answer is that if you applied yourself equivalent to going to college for four years and earning a degree in blacksmithing as a business, studying art, drawing and design as well as welding and metalurgy you could become a blacksmith. By concentrating on the smithing only it can be done in much less. A month with Frank Turley and another with Uri Hofi and you would be ready to go to work for someone else or yourself and be an asset in the shop. But there is a LOT more to the business than just forging iron.

See my comments on the cost of an education in smithing in the Sword Making FAQ and the apprenticeships FAQ. See also the resources list in the Sword Making FAQ. Many of these need to be listed

All the books listed in our FAQs and most of our book reviews are currently available new, used or in reprint. To purchase ALL of them is the least expensive part of learning to be a smith.
   - guru - Sunday, 08/15/04 04:41:28 EDT

Matt, A saltbath contains MOLTEN salt. The objective of this process is to quench rapidly down to the temperature where the martensite begins for form (about 700F), then you pull the part out of the saltbath and let it slowly cool. This process keeps delicate parts from distorting due to the struggle between the thermal contraction and the volumetric expansion of the martensite formation. It works well with things like blades. However, it is not a process for the amature to tackle. Some of the salts used are quite toxic and dangerous. Just a bit of moisture in your salt and you could have an explosion. However, do a search for the term "fluidized bed" and you may get some ideas for a substitute.
   quenchcrack - Sunday, 08/15/04 08:28:54 EDT

Salt Baths: Matt, As QC pointed out there are significant hazzards with a salt bath. However, in blademaking they are often used for more than just quenching and tempering they can also be used for the initial heating to harden. One important advantage is lack of serious oxidation of the surface.

Don Fogg has an article about making one on his web site. However, it is not a cheap easy thing to build. Besides the pot there is no advantage unless you can measure and control the temperature. Temperature controls are not cheap starting at hundreds of dollars. Occasionaly folks build their own but they can be quite technical and home built lack many conviencences.

But this is one of the costs of doing professional work with modern alloys. Plain carbon steel has been heat treated sucessfully by seat of the pants and smithy methods for centuries. But modern high carbon tool steels often require very close temperature controls to have any advantage over other steels.

Recommended Study: If you want to study heat treating methods and tools used by modern bladesmiths I highly recommend Wayne Goddard's books and videos. Also the series by Dr. Jim Hrisoulas. Studying this small collection will advance your knowledge of the craft greatly as well as expose you to tricks and ideas that have taken these men lifetimes of study. Jim Hrisoulas' doctorate is in metalography and he has experiance in working some of the most exotic blade materials known to man including using metoric iron slabs as inlays. Wayne Goddard has raised the art of the cable Damascus blade to a science and is a genious at contriving special tools and machines.

The top people in the field of bladsmithing have spent a lifetime of study. Folks like Jim Hrisoulas and Daryl Meier have advanced degrees in metalworking or engineering subjects. With that education as a base THEN they started to learn the trade. They made many of the mistakes we all did at first but the did so with the knowledge to understand and correct their mistakes. And yes they will be the first to tell you that you never stop learning in this trade.

Get the books. STUDY them. Don't just read them. The various forums on the Internet do not replace studying the literature and can often be full of misinformation or in the least be incomplete.
   - guru - Sunday, 08/15/04 12:12:12 EDT

On becoming a smith: At the SWABA meeting yesterday the demonstrator gave a brief overview of his background---I hope I remember it right; first he spent 3 years training under a professional smith. Then he did a 1 year "journeyman's" journeying (South Africa, Europe) working with other smiths. Upon returning to the States he worked 3 years as a subcontractor producing forged items for another person's large scale comissions. *then* he went out on his own and currently shares a shop with two other metalworkers all who work independently and together with their subspecialities--Alex did I get that right?

If you are really interested in the craft it's a good idea to start ammassing the necessary tools *now*; before you are trying to support yourself, gain a reputation, *and* buy the stuff you really need to turn a profit! (Helps if you have a secure place to store stuff until you are ready to set up shop)

Note: if you get in good with some builders you can get a steady flow of work---the best reputation you can get with them is TO BE ON TIME; If you are always ready on your agreed on date they will prefer you to a "better" artist that routinely misses the deadline by a month or more.

Thomas---still just a hobby and I like it that way!
   Thomas P - Sunday, 08/15/04 15:44:37 EDT

Thomas, I, too, appreciate smithing from a purely amature perspective. I give away more than I sell. As the Alpha Guru often points out, earning a living as a smith is too much like work. I pound iron to relax, to create, and enjoy the company of like-minded individuals. To make it a profession would rob me of the joy of the craft!
   quenchcrack - Sunday, 08/15/04 15:52:59 EDT


I'll certainly second that! When the ink was still wet on my BFA, I opened a metalsmithing studio and did it for a living. One year of that was enough to drive me to police work. (grin) It was a long, long time before I picked up my tools again and got back into it. Now I do it only for fun. Oh, I'll take a commission if the price is right and the client is my kind of client, but this is really a hobby at this point, and I'm quite content with that.
   vicopper - Sunday, 08/15/04 17:59:30 EDT

I have a question for the Super Quench Guru.
Guru Sir, in your research with Robb Gunter's brew have you found that the hardness (42-45 rockwell) imparted to a low carbon or mild steel has reached the center of the bar? In other words, is this stuff another fancy case hardening compound? I have read a lot of testimonials and scientific explanations of what's going on during that split second when hot steel meets Dawn liquid and friends, but no one is saying just how deep the hardeness goes. Do you know? Will you settle this for me?
Thank you kindly.
   wendy lawrence - Sunday, 08/15/04 18:58:09 EDT

Hey Roach, My best advice to you is to LISTEN. Got ears?!
   - PapaDoc - Sunday, 08/15/04 20:11:14 EDT

Hey Roach, My best advice to you is to LISTEN. Got ears?!
   - PapaDoc - Sunday, 08/15/04 20:11:30 EDT

Whoa! My last post was obviously not proofed. I guess I was in a hurry. As things turned out, Charley moderated and swung east, just leaving us with a small shipload of rain. No complaints from one of the LSCo board members in coastal NJ in his recent missive, so it must have eased back considerably. Some friends of the family did have property and a boat where it came ashore, but since they're up in Maryland for the summer, no word on how the property made out.

Becoming a Smith:

It also helps to remember that besides being an art in itself, blacksmithing is also a means towards various ends. You exercise skills to make stuff. We have Boy Scouts making tent stakes and S-hooks on the first go-round; and if you ambition ends there, then it doesn't take all that long to become a "tent-peg-S-hook" smith.

For me it's also one of several methods to research and understand the technological history of early medieval Europe and other societies. Others do it for artistic endeavors, or as a living in heavy industry, or as farriers, or armorers, or swordsmiths, or they do fencing and gatework or architecture. Each of these activities have different training requirements and learning curves.

As for me, I strive for competence. The motto for Oakley Forge is:

Tools for peace,
Wares for feasts,
Weapons for war,
Art for the fun of it

Works in the 11th century, and in the 21st.

Raining and cool on the banks of the lower Potomac.

Visit your National Parks: www.nps.gov

Go viking (updated with a recent picture of the new longship): www.longshipco.org
   Bruce Blackistone (Atli) - Sunday, 08/15/04 21:06:12 EDT

Wendy, You are obviously astute enough to have realized that quench velocity is limited by the thermal conductivity of the steel. Since most low carbon steels lack the alloy necessary to push the pearlite nose to the right, you will get a thin skin of martensite over a core of pearlite and ferrite. This is not to say that superquench is not useful, it just cannot make a silk purse out of a sows' ear, especially if it is low carbon pig. However, if you are making knives, you might be surprised what kind of hardness you can get with only .30% Carbon in superquench. Just don't expect this blade to hold an edge for long because abrasion resistance depends on high carbon content to form iron carbides in abundance.
   quenchcrack - Sunday, 08/15/04 21:12:17 EDT

Roachburn & Wendy-- There is no free lunch. You get out what you put into it. Unless you believe in alchemy. You can futz around with a forge for years inventing the wheel or you can go to a good smiting academy like Turley Forge and learn to do the basics right fast. It's like shooting pool, you dig? You pick up your shots, but you can't win just making shots, so then you spend your life refining your position game, your strategy. Moscone practiced five hours a day. Every day. For 55 years.
   Goods Inward - Monday, 08/16/04 00:24:55 EDT

While I have not had the pleasure yet to attend one of Franks classes, I did have a chance to visit with him this summer for a short bit. Great guy.
   Ralph - Monday, 08/16/04 00:35:35 EDT

Wendy, one other thing, case hardening compounds work by increasing the carbon content of the surface of the piece. Super Quench does not increase the carbon content of the piece so it's not a case hardening compound.

   Thomas P - Monday, 08/16/04 09:37:30 EDT

On the Phone: I've had intresting long distance phone calls the past few days. People inquiring about purchasing re-bar, forges and anvils. Our re-bar articles put us at the top of some searches for the product even though we do not sell it. I've also had long discussions with folks about using Kaowool for various purpose. About half the time I recommend other methods for what they want to do.

In the Mail: I've echanged mail about getting started in blacksmithing with folks in Costa Rica, Argentina and Australia. Lots of Kaowool questions in the mail too.

The big misconception about high temperature high efficiency insulation is that is will prevent the outside of a forge or furnace from getting hot. Even though Kaowool is very efficient it does become hot and eventually start to transfer some heat. For short runs of less than an hour a forge shell with 2" of Kaowool may remain cool to the touch. But as the device operates longer more heat eventually reaches the shell. The maxium shell temperature is then determined by the percentage of energy reaching the shell and how much the shell cools in the air. Kaowool transfer a low percentage of the heat but it DOES transfer some heat. If the heat is given off to the air as fast as it is transfered then the shell will reach a given temperature and no higher. But it will not remain at room temperature. Predicting this temperature is very difficult. One of the best methods of producing a cool shell is to have a double shell with an air space. The air space must allow for circulation of fresh air so that the inner shell can cool. This system will produce an outer shell that stays very close to room temperature if there is sufficient space and circulation.

People also want to apply Kaowool to the outside of furnaces. This WILL reduce the outside temperature but the shell sandwiched between the Kaowool and whatever refractory is in the furnace will get VERY hot. It can easily get TOO hot and burn up or collapse. These shells rely on air cooling to prevent overheating. Adding insulation outside is not a good idea.

ITC-100 reduces heat trasmission and loss to the insulation and therefore reduces shell temperatures. But to calculate the exact amount of reduction is almost impossible. In a few applications the reduction is hundreds of degrees F. This is a percentage of the heat transfered without the ITC-100. Over time this percentage will often drop as the ITC surface degrades from soot sticking to it. Where there is no soot or dirt the eficiency will remain high but in dirty applications the coating must be reapplied at regular intervals.
   - guru - Monday, 08/16/04 09:57:39 EDT

I've started forging and im afraid too much carbon is boiling out of the steel, is it a problem? and if so, how can i prevent it? Thank you.
   - Bonis - Monday, 08/16/04 11:54:51 EDT

I'm very new to this whole site & to blacksmithing, I came to this site becuase I have read that its the best, and after looking around, I have to agree! This site is really good and helpful!
But anyway, to the point, my question is, and forgive me if it seems very stupid of me: What is a pitchle used for? and also, do you use it with the pritchle hole? becuase I have thought that thats for punches.

Thank you very much, and again, Great site!
   Marcus C. - Monday, 08/16/04 12:07:54 EDT

Pritchell hole Marcus, A pritchell is the slender rectangular punch used by farriers to hot punch the nail hole in a horseshoe. The small round hole in London and American pattern anvils is used for this punching operation and is called the pritchell hole. Many farriers' anvils had two pritchell holes.

Like all the features on an anvil the pritchell hole is multi-use. It is handy for punching small holes, bending round bar and any other use that the imaginative blacksmith thinks of.
   - guru - Monday, 08/16/04 12:47:21 EDT

Carbon: Bonis, Carbon is either absorbed lost depending on your fire condition. If the fire is rich or carburizing the steel will absorb carbon. If the fire is lean or decarburizing it burns carbon out of the steel. In a coal fire both conditions can occur simultaneously. In oil and gas forges you usualy have on condition or the other. Gas forges are difficult to run rich and oil forges are difficult to run lean.

In decorative smithing neither condition is critical. In forging tool steels it is not critical unless you are using too many heats (too big of work for your capacity).

In forge welding laminated steels and slender blades decarburization can be a serious problem. On welded billets it is usualy handled by grinding off a significant part of the surface. On thin sections you usualy avoid decarburization by not soaking the part in the forge and working quickly. For the smith working by hand this means starting with a reasonable size stock. Most newbies start with stock that is much larger than the finished product and the steel spends much too much time in the forge. Rather than using big flat leaf springs most blades can be forged more rapidly and with less effort from coil springs or round stock.

When heavy stock is made small you either need helpers to strike or a power hammer. Since labor is relatively expansive modern smiths use power hammers.

In some cases the decarburization is used to advantage. When smiths make cable Damascus the decarburization creates the differences that make the pattern when etched. If there is no decarburization then there would be no pattern.
   - guru - Monday, 08/16/04 13:12:34 EDT

Thanks for the info. As always, it'll save much time and greif.
   - bonis - Monday, 08/16/04 13:40:56 EDT

I have asked a reasonable question here. I find your flippant and assumptive replies annoying. Goods: your billiards analogy is irrelevant to my question. You dig? I am not asking how to make a sword out of a piece of rebar or how to become a blacksmith. So, let's get one thing straight: Girls have cooties and they only know about Barbies!
I understand that the amount of carbon that a steel contains will directly affect how much martensite is formed upon quenching that steel. I also understand that 1018 type steels do not have a high enough carbon content to form a martensitic structure at all, but will form a bainite structure upon rapid cooling. Rob Gunter's Super Quench formula was derived out of the necessity to replace sodium hydroxide as a quenching medium for low carbon steels. Super Quench will yield Rockwell ratings of up to the 45 range. Amazing but true. Now, if there is not enough carbon to create martensite, yet the steel is undeniably hardened, how would you best describe that result? Case strengthened?? Sounds like case hardened to me. Now, back to my original question:
How deep does the hardening go? If you use Super Quench on a .30% carbon RR spike, I would guess that you could expect at least a little bit of martensite to form, right? What if you didn't use Super Quench on the spike- just cool water? Could you expect some martensite? What if I were to quench 1065 in water (careful, this is a test)? How deep does the martensite form? I would guess that there is more at the surface than at the center of the bar. What have you found to be true?
Thanks for your help.
   wendy lawrence - Monday, 08/16/04 14:39:46 EDT

Wendy, generally super quench has the same effect as quenching in very cold water. The surface effect QC was talking about is quite thin and should not be called "case hardening" because that is a specific process where extra carbon is put into the surface of a steel and then hardened.

Variations in hardening have more to do with the section thickness than quenchants. Thin parts quench rapidly and have nearly uniform structure. Thick sections often have great variations in hardness as one approaches the center.

Although RR spikes are supposedly marked HC if more than 30 point carbon I have witnessed spikes being manufactured from old RR car axels (40-50 point carbon) and RR-rail (60 to 75 point carbon) that had no markings. The plant in Richmond Virgina made many millions (car loads) of spikes from these materials.

SO, without careful testing any unmarked spike is no different than any unknown junk yard steel.

Currently steel bought as "mild steel" is most often A-36 but I have heard reports of other structural grades with higher carbon being sold as mild steel.

I am not an expert on metalurgy so I cannot answer your more technical questions. But my problem with starting points is a valid concern. You hear about people making this that and the other from rebar and hardening it but what grade? There are three with considerable carbon content differences. Which one was used? I have bought bundles of CF steel bar that had a mix of SAE 1018-20 and something MUCH higher carbon. Quenching it in water made it as brittle as glass. I made a bunch of fire tools from it before I had a handle fall off in my hand. . . So when I hear of people claiming various results outside of using certified materials and testing under laboratory conditions I am sometimes skeptical.
   - guru - Monday, 08/16/04 15:10:00 EDT

It is looking more and more like you are trying to get someone else to do the research for you. Almost like a test question. Since you did not like the answers to a not so clear question you started getting angry and almost calling names etc.... perhaps you might calm down and ask nicely or just test it out yourself.
   Ralph - Monday, 08/16/04 15:21:13 EDT

I'm sorry Wendy if my reply was seen as flippant; perhaps we should add "shallow hardening" into the fray to include such things as super quenched mild steels.

One thing to remember is that questions are often answered for a larger audience than just the asker; so what may be insultingly trivial to yourself may be a "light bulb" moment to someone reading this without the background. I learn a heck of a lot reading some the the answeres and am very happy to plow through the stuff I know to get to the stuff I don't.

I don't know how deep the hardening goes; I'd think it would vary as a function of alloy, starting temp and rate of cooling. If someone wanted to do the experiment hardening a spike of known content, testing it then using a surface grinder to work slowly down through it while testing at regular intervals would give an idea of the drop off---just an idea if we have an MatSci students reading this who need a school project...

Thomas; guess I'd have them too being that I've been married 20 years now
   Thomas P - Monday, 08/16/04 15:34:58 EDT


You may want to look back up to Quenchcrack's answer, it seemed to cover your question. In fact, I have now learned something today, which is not often a pleasure I get at work.

As I understand it, you do get a very hard surface, but you are not adding carbon to the mix, which is what case-hardening does. I suppose you are sort of inverse case-hardening by creating a very slight martensite layer over the less structured layers beneath based on what carbon is inherent in the material. All this without adding carbon.

That seem about right?

For the record, I got lost in the billiards analogy as well.
Also for the record, my wife is a girl and doesn't have cooties . . . at least none that I am aware of.
   Escher - Monday, 08/16/04 15:47:06 EDT

Dang, I am slow.

read the other posts and ignore mine.

   Escher - Monday, 08/16/04 15:48:03 EDT

I heard Rob Gunther's demo a few years ago,in fact I mixed the superquench, and I believe he described the standard test for hardnebility. They quenched a 1" round bar of known carbon content, they then sectioned the bar, in the proper manner, IE wet and imparting no heat, and then did a transverse measurement from the od to the center. This was done at Scandia, according to Rob. I do not remember the exact depth of hardness, but I think I remember him describing some revelent depth of hardness.
I also remember him saying that it stumped the metalurgists, as they had no answer to the hardness.

I have always heard the term casehardened to refer to a process that adds carbon. I have seen differential hardness imparted on purpose, as we do to axles. It is a function of the alloy and heat treatment practice. I think the superquench is a function of the quench velocity, and the amountof carbon in what most people assume is low carbon steel. I have had A-36 that when quenched, would strip the M-2 teeth off a bandsaw. As the Guru noted, if its not certified, its anybodies guess as to what it is. I used to work for a company that bought millions of pounds of traceable steel a year. We tested a crop end off every bar, and it was amazing how much steel we rejected as not to spec! And this was steel tracible for ASME code rated vessels, piping, fittings,Nuclear valves and fittings, US NAVY ships, and boilers. If tracible steel was not to spec. direct from the mill, what chance do you have at the local service center, selling from a pile of who knows what.
If its critical, test!

   ptree - Monday, 08/16/04 17:25:09 EDT

Ralph, Wendy is a regular here. She is not a student asking us to do her homework.

Goods Inward, your real e-mail address may start getting the mail sent to your bogus addresses. . .

Super Quench on Mild Steel: My feeling on this subject is that in our modern society there are too many auto springs lying about for people to be super quenching mild steel to get a hard part.

That is not to say that I do not make mild steel tools. I do that all the time. That includes dies for use under a power hammer. I have forged hundreds of tennons using a two piece die made from SAE 1018-20 CF bar and a spring made of the the same in 3/16 x 1". Forging hot mild steel the dies showed nothing more than a polish from use. These dies were made cold and not heat treated.

Now punches and similar hot work tools are another matter. And this is where it is a mistake to try to use a low to medium carbon steel hardened to harder than normal. The problem is that these steels rapidly lose their hardness by tempering at relatively low temperatures. So it can be a huge waste of time. And as I mentioned, there is too much real steel lying about. Good hot work steels are also not so high in price that they cannot be used when needed.

THEN there is the fabled Atlantic-33 non-tempering hot work steel. I think those nifty thin hot cutters are made from something similar. . .
   - guru - Monday, 08/16/04 17:26:32 EDT

There seems to be some hair splitting going on here. I would love nothing more than to share ongoing friendly and respectful discourse with the Gurus, members of the Cybersmiths, and the chimers-in. I value the combined knowledge base that exists here. I hope that the split hairs and ruffled feathers do not interfere with my access to that knowledge. That said, shall we continue?

It seems that Super Quench is still somewhat of a mystery. If no carbon is imparted and there is not enough carbon to create martensite to begin with, what function or reaction is creating the hardness? It also seems that the only accepted definition of case hardening is when carbon is added. OK. Does anybody have an accepted definition of the Super Quench hardening process?
   wendy lawrence - Monday, 08/16/04 18:35:17 EDT

My last post should have slipped in between Escher's last post and ptree's post... Anyway
""Super Quench on Mild Steel: My feeling on this subject is that in our modern society there are too many auto springs lying about for people to be super quenching mild steel to get a hard part."" I can not agree with you more. There is a time and a place for tool steel and sometimes we can get away with using mild steel for tool making processes.

This whole mess started when someone suggested that I use Super Quench on a spike knife. At that time I understood that Super Quench created a hardened surface, which it does, but we're not allowed to call it case hardening because no carbon is being transfered.
I guess if I want to make a knife I should just use a known steel. Sheesh. I thought that spike knife was kinda cool. I felt like it was part of the smith's right of passage. You know? How many of you have NOT made one yourselves???? What kind of questions did you come up with when it was time to heat treat it?
   wendy lawrence - Monday, 08/16/04 18:51:02 EDT


Last one I made, I heated to non-magnetic, and quenched it in SQ. Took a decent edge, (not outstanding) held it for most of a deer.

Why does it work? I've got a bad case of I and A about that. Ignorance and Apathy. I don't know, and I don't care why it works.

To me, all that matters is that it does help when working with relatively low carbon steel.
   Paw Paw - Monday, 08/16/04 18:55:54 EDT

my quess it that the soap and ohter additives only lower the surface tension of the water allowing in to be more 'wet' and so flow over the metal better. which will allow a faster cooling of the metal.
Is this so? I do not know. Perhaps the best answer is it is akin to magic... (grin)
   Ralph - Monday, 08/16/04 19:00:08 EDT

Wendy, ok so we take the gloves off and get to the straight poop. The formation of martensite does not depend on the presence of carbon. Brass will also form martensite. Martensite is a body-centered-tetragonal structure whether it is iron or something else. It is a diffusionless shear transformation that occurs instantaneously over a range of temperatures. Carbon has the effect of causing severe lattice strain because it becomes trapped in the interstitial sites within the lattice. The amount of carbon controls the amount of hardness because more carbon causes more strain. Quench velocity in excess of the critical quench velocity will not add to the hardness. The concept of hardenability infers that the depth of the transformation into the steel can be altered by adding alloys which surpress diffusion and allow time for the iron to reach the Ms temperature without transformation to ferrite/pearlite/bainite. Quench velocity can affect the depth of hardening but not necessarily the hardness. Superquench does modify the surface tension of the quench/metal interface and affords a more rapid heat transfer which can harden a thin skin on a "non-hardenable" steel. Just because the metallurgists at Scandia could not figure it out does not mean metallurgists elsewhere cannot provide an explanation. The folks at Sandia probably never have to work with humble metals like steel.
   quenchcrack - Monday, 08/16/04 19:34:20 EDT


I have never made a spike knife, myself. Not so much because I don't have any spikes (though I don't), as because I'm unwilling to make an edged weapon from an unknown, and likely unsuitable, material. I have too much love for really fine edged weapons to make an inherently inferior one when better materials are lying around decorating the roadsides. Also, very few if any people here would have any appreciation at all of the folk art qualities or historical interest of a spike knife, never having had a railroad in the Territory.

Spike knives do look "kinda cool", I'll agree. They're also unbalanced, too heavy and not that comfortable, relative to a well-crafted knife made in one of the customary ways. As a novelty item or a letter opener they make a fine project, but they'll never really be a good edged tool, so why bother with any hardening? Leave it soft so it doesn't get broken.

My best guess on the effectiveness of SuperQuench is that its effectiveness is the result of the higher specific heat of the brine plus the wetting agents decreasing the steam jacket that results in a much faster quench slope. The few times that I have tried using it, I didn't feel that it resulted in sufficiently greater hardness to justify having steaming brine in my shop rusting everything in sight. Just my opinion, your mileage may vary.

As to the issue of cooties, well, that's just too personal and probably more information than I really can handle. (grin)
   vicopper - Monday, 08/16/04 19:42:11 EDT

I've made spike knives, and currently make garden trowels and garden knives from spikes. Somewhat of a novelty, but the fact that if quenched in water, and tempered back a bit, they are what a spike metal is desired for. TUFF. I know that people will try to pry roots out ECT. And with a not very hard, but very tuff, steel thats safe. Spikes do make a very nice item if you forge a face just under the cap. Draw out the end, round it and put in a curve. Nice coat hook, and nobody can argue about the steel quality.

As the guru notes, when you use junkyard steel, a little knowledge in what the item was used for, helps.:( In todays world of micro alloys, high strenght-low alloy steel etc. it helps very little. A test helps, but if its important, buy new. I do use alot of spring steel, and axle steel. The axle steel I get scrap from work, and I know the alloy. Springs I asume the alloy, and start from there. But I test a sample item for function. Then, after I'm sastified that the thing is safe, if it's garden related, as much of my work is, I pass it on to my R & D dept. I have a 5 person R & D dept as I have family that is every bit as serious about gardening as I am about blacksmithing.:)Boy are they quick to tell me my failings as to form or function. If it passes the R & D dept. then I figure its safe to sell.
   ptree - Monday, 08/16/04 20:00:50 EDT

I have two questions about welders. I am trying to run a Lincoln AC 225 buzzbox of my 5000 watt continous generator. I have a 20 amp breaker on the 220 plug. How many amps on the welder can I use befor I pop the breaker. Or should I just try it. Next My buddy has a old SA 200 Lincoln. It runs perfect but produces very little arc. There is a "govener" type thingy that I have read Lincoln no longer produces could this be the culprit. Thanks in advance.
   Ed Moore - Monday, 08/16/04 20:01:05 EDT

Ed moore,
A watt is volts times amps. So 100 volts at 50 amps= 5000watts. At 200 volts that 5000 watts=25 amps, and at 220 volts, thats 22.72 amps. Now thats at the generator.
For the amp draw at the welder, you need the voltage. Look to see if the nameplate has a weld current voltage, or a full load amp rating.
Now all this is theoritical,and you should know a couple of things. A good new strong circuit breaker will let a little more current thru for the start of flow. Second most generators are rated at PEAK watts and CONTINUOS watts. Most 5000 watt peak generators are around 3500 to 4000 continuos watts.If I remember these welders correctly they are set up with a 220 volt 30 amp plug, and are intended for a 30 amp circuit. You can't get there from a 5000 watt generator, at full load. You may be able to run at lower load, but you also have to deal with lag on the generator. As the load comes on, the govenor pulls the throttle, and engine speed increases. I'm not sure how this will effect the weld arc at start. I have welded with engine driven welders that had a slow governor, and it pretty tuff to get an arc going.
   ptree - Monday, 08/16/04 20:18:59 EDT

Wendy et al., I studied social studies and liberal arts in school, so I can't get too metallurgically technical. I can tell you that I have a bucket full of rr spikes, but I don't intend ever to make a knife of a spike, as I feel they look dorky. Robb Gunter told me a number of years ago that he used caustic soda to obtain the "super quench" hardness. He wanted to continue using it, but the powers that be at Sandia Lab classified it as hazardous...told him to get rid of it. Apparently, that's why he came up with the detergent/surfactant formula. I have never used the super quench, because it seems a bother to gather all the stuff together to get a little surface hardness. I prefer to purchase a known steel and use brine, water, still air, or quenching oil (Quenchtex A) for my small shop work.
   Frank Turley - Monday, 08/16/04 21:31:29 EDT

Generator Running Welder My old Miller 275 states that it requires 90A 240VAC circuit breaker. However, I never run anything bigger then 1/8" rods and always ran it on a 60A breaker. It is not unusual to find these plugged into a 45-50A stove outlet. However, 20 amps is REALLY pushing the limits.

Under normal use and arc welder runs at about 30 volts and 125 amps (for that 1/8" AC rod). That is 3750 watts when the arc is stabilized (17A @ 220V). But when you strike the arc or if it sticks a moment the load spikes and you draw at LEAST double (7000 watts or 34A @ 220V). A stone cold circuit 20A breaker will take that once. But if you have been welding at 3/4 capacity of the breaker it is going to be hot and the first rated capacity surge (striking the next arc) and its going to trip.

If you run nothing but 3/32" rods and are carefull not to stick them you MIGHT get away with it.
   - guru - Monday, 08/16/04 22:40:52 EDT

superquench: Heh, I feel bad now, that was my fault.

"This whole mess started when someone suggested that I use Super Quench on a spike knife."
   AwP - Tuesday, 08/17/04 02:06:34 EDT

I sincerly appreciate all of the honest and thoughtful responses. AwP: You are not responsible for this mess- I mean coversation... As it turns out, we were both correct. The turkey is cooked no matter how you want to "define" the end result. FYI: I will not be making up a batch of Super Quench, I will continue to play around with the bucketful of spikes I have accumulated- even if the items are dorky or too low-brow for some folks, and I will continue to study metalurgy.
More on martensite and hardening processes: what's happening as the work hardening process is taking place?
Does bronze (I don't know the exact alloy) take to work hardending ?
And BTW: Why the hell didn't R. Gunter just use Kase-nit??????????????????????
   wendy lawrence - Tuesday, 08/17/04 10:15:56 EDT

Work Hardening: Wendy, Brass, bronze and practicaly all metals work harden. Gold is one of the few that does not and stainless is particularly bad.

Scythe Anvil
During the Bronze Age swords were primarily cast but the edges were sharpened by hammering thus producing a hard edge. I suspect the little scythe anvil and hammer date from this time. These little "pocket" anvils were used to sharpen scythes that were used to harvest grain and cut grasses. The hole is so that the anvil can be tied to a laynard to keep from losing it. It was probably attached to a small hammer handle to keep the two together. The spike is for driving into the nearest convienient tree root, log or stump. They are still manufactured by Peddinghaus Tools of Europe.

LEFT: Scythe anvil photographed at SOFA Quadstate in 2003.
   - guru - Tuesday, 08/17/04 11:14:49 EDT


Most metals will work harden to some degree. To understand work hardening you must first have an idea of what metals are like on an atomic scale. Metals are crystalline solids which means the atoms are arranged in an orderly, repetitive fashion called a lattice. The lattice can be shifted locally when stresses are applied. Imagine a graph paper with some of the lines indeneted one space to the right of all the others. When this happens we call it a dislocation of the crystall lattice. These dislocations can move through the lattice like a wrinkle in a carpet. When the disloction encounters a grain boundry, it stops moving. Subsequent dislocations will be trapped by the first one. The more dislocations you have, the harder it is for them to move around and you end up with and increase in strength because more stress is needed to get them to move. The whole effect can be nullified by annealing.

   Patrick Nowak - Tuesday, 08/17/04 11:30:08 EDT

Kasenit or Casenit: Wendy, Casenit is a salt hardening compound used to put a "superficialy hard" surface on steel. It used to contain Cyanide salt (sodium cyanide). This is the same substance used in gas execution chambers. Add a little acid and cyanid gas is liberated. If you think you have a hazard using a lye bath for quenching this is a REAL hazzard!

Casenit and other salt surface hardening compounds only produce a hard layer a few thousandths of an inch (~.03mm) thick. So beside the hazzard of the cyanide you get very little benifit.

Cyanide surface hardening is used to produce a wear resistance surface for bare metal and blued parts like on firearms. It is used on small threaded hardware to prevent galling and ocassionaly on shafts to impart a hard long lasting bearing surface.

Casenit is discussed in our case hardening FAQ. See the time and temperature chart. Consider the times given and the results that you would get using Casenit, a torch and a few minutes heat.
   - guru - Tuesday, 08/17/04 11:32:50 EDT

If possible, find a Dec 1966 Analog (a magazine) and read John W. Campbell's editorial titled "Too Many Chiefs" I think it should be required reading for every engineer, scientist, and artist. (most smiths are all three of these? I kinda think it might be pertinant to Wendy's question about WHY the superquench works.
If any one knows where it could be found online please let me know.
   JimG - Tuesday, 08/17/04 12:00:17 EDT

I wasn't sure if this was the right place to ask this question, but after reading the Guru's article on bells gong's etc in the FAQ and knowing the very wide knowledge base of those that frequent here.....
Why do musical instrument strings (which are made of steel)
need to be played in before they develop their full sound, and after awhile loose their full sound?
I'm thinking of fiddle strings in particular, but I think it applys to most.
Anyway just a ramdom query, the world isn't going to end.
   JimG - Tuesday, 08/17/04 12:06:10 EDT

Why didn't Rob just use Casenite?---Cause he's a blacksmith and so ornery by definition. Actually IIRC he was trying to figure out if the old lye quench he had heard about actually worked and found out that it did and was trying to figure out why.

Work hardening bronze---yes it works but you have to learn when to stop---before it starts cracking---and this will be different for different alloys.

IIRC traditional pewter also has a dislocation climb temperature below room temperature so you can "anneal it" just by letting it sit a while.

Lets see if I got this right: carbon acts as sort of "artificial dislocations" if it gets trapped in the lattice and doesn't have time to diffuse to a location where it won't disrupt the lattice?

   Thomas P - Tuesday, 08/17/04 12:11:14 EDT

Strings: JimG, I have heard about "playing in" from various sources. I do not think this has so much to do with the string physics as much as the fits at the string ends (bridge saddle and nut) and the instrument changing. With time and use the bends at the string ends straighten and settle in, the string also finishes stretching. According to my brother Paul who is a an execelent guitar player and who has p;ayed with some of the best most of what you hear about strings settling in is a myth.

The instrument itself has a settling in period as it flexes in response to the string tension. Most of this occurs immediately but then there is a period of days where the shape changes and retuning is necessary. On first class acustical insturments this should only be a day or so. However some are tempermental and may change for a week. There is a big difference between changing one string at a time and restringing the entire instrument.

Most stringed musical instruments are a "high performance" device. In order to have good response and volume they are built to be VERY near the breaking point. The typical guitar has about 250 pounds of total string tension. This is supported by a thin wood box that only weighs a few pounds! Bases have more tension, violins less but they all are highly stressed devices. Many are commonly dismantled and repaired in response to the destructive stress. The big 7 pedel concert harps are the worst. The sound boards are made of many narrow strips of spruce glued edge to edge in order to put the grain across the sound board the strong direction. These usualy have a decorative verneer to cover all the joints. Under load the glue joints eventualy fail and the sound board has to be replaced.

Wraped strings DO wear out. The constant tension stretches the core (wire, nylon, gut) to the point that the wraps develop spaces between them or become loose. This can take many months to a year even when the instrument is played regularly.

Strings DO lose a little of the brightness of sound after a few months but on a good well maintained instrument this may be barely detectable for as long as a year or more.

Now. . Many concert musicians, expecialy those playing rock or modern music start with new strings for every performance in order to be sure not to have a string failure. On acoustic instruments they must be put on a few days in advance to let the instrument settle in. On electric guitars it may be done immediately before the performance.

My brother Paul is primarily a computer geek but he has examples of his music on his site to download at PaulDempsey. com. There is also examples of music by my late brother Shawn who was a professional muscian. AND Paul's son Jacob is the basist for The Non-Profits. Both of these web sites were built by my brother Paul and run on a product he developed called X0base.

Although I have fooled with building stringed musical instruments and play my couple short little diddies the musical gene missed me entirely. . .
   - guru - Tuesday, 08/17/04 13:43:20 EDT

Wendy: Tai Goo has had surprisingly good luck hardening spikes in an agitated oil quench, though his forge is amazingly carburizing too, I don't think most people could get away with using oil. Maybe a vibrating water/brine quench will give a similer effect to the superquench?
   AwP - Tuesday, 08/17/04 14:14:00 EDT

Thanks Jock,
The reason that made me think of asking is that my guitar player and I both changed strings at the same time, and until last night we were ready to put the old ones back on.

And yet another reason to be a CSI member (other than your name in blue) you can ask rather strange questions and get a well thought out answer without fear of being ridiculed because your known.
   JimG - Tuesday, 08/17/04 14:21:08 EDT

Jim, My brother has some rather nice guitars. He says most should settle-in in a day or so. However, his old Guild is very finiky and takes a week or so to get right. He is currently looking for a first class jazz arch top and says they are VERY finiky and also take as long as a week to get to a stable shape. Fiddles, violins, the whole viol family in fact, are the highest stressed of the stringed instruments and the settling in will be the longest. IF the strings were the factor then this period would be very uniform beteen all instruments.

As noted he advises changing one string at a time. But sometimes you just have to bite the bullet. My guitar has the original strings I put on it when I built it. . 8 or 10 years ago. The last time I played it I noticed they had rusted so bad that they felt funny! Definitely time for a whole new set of strings.

The guru's Guitar - Design (c) Patrick Dempsey

My guitar is an unusual design that my son Patrick came up with. It is the arcs of laying out two equalateral triangles. He wanted to build a guitar, I let him design it and I came up with the details. We built two, one for each of us. Those corners din NOT make them eaiser to build. Each was a little different in detail. His had a "Western shirt" inlay in the small bout and a triangular sound hole. It also had a trapeze style bridge. Our trapeze design used an ebony block for the strings and stainless tension bars that anchored on an ebony stud. It worked well but we did not allow enough neck angle for a high enough bridge to get sound transmission to the soundboard. . . live and learn.
   - guru - Tuesday, 08/17/04 16:13:17 EDT


Carbon serves a different fucntion than dislocations in the role of hardening steel. Martensite, (with carbon in the Face Centered location of the crystal lattice) has a greater volume than ferrite/pearlite where carbon is at the Body Centered position. This volumetric change induces a stess on the steel resulting in increased hardness. Dislocations don't change the volume, they interfere with further slipping of crytal planes. So, they are two entirely different mechanisms with different end results.

   Patrick Nowak - Tuesday, 08/17/04 17:04:59 EDT

coal bed,

I'm building a coal bed for my for and need to know why the erea around the firepot has a verticle dip all the way across it. And is it neccesary?
   - New blacksmith - Tuesday, 08/17/04 18:00:28 EDT

I am thinking tht perhaps you need to decribe the forge that you are trying to copy a bit more clearly and completly. At least I am not sure of what it is you are asking. I think that you are asking why is there a lower section in front of and in back of the fire pot on the forge. This is so that the smith can have longer pieces of iron or steel in the hot spot of the fire. At least I think that is what you are asking and or are describing.
   Ralph - Tuesday, 08/17/04 19:09:11 EDT

Does draw quality steel have a lower carbon content than mild steel? I heard it has a shelf life--what does this mean? Are there any steels available that have a lower carbon % than mild steel?
   todd - Tuesday, 08/17/04 19:42:45 EDT

Todd, You have been talking to some VERY confused people if that is what you heard.

Shelf life means its useful life expires on a certain date after manufacture. Like a bottle of milk next week or a box of cereal next year.

Steel of any kind has no "shelf life" any different than a block of granite . . other than the fact that the steel may rust to dust in the time it takes the granite to weather enough for moss to start growing on it.

Cold drawn steel is usualy SAE 1018-20, that is it has a carbon range of 0.18 to 0.20 percent and meets SAE specs for low carbon steel. In the recent past if you asked for "mild steel" this is what you got in either hot roll or cold drawn steel or CF (cold finished) steel. Today some CF steel is SAE 1018-20, some is sheared and cold rolled A-36 (structural grade steel). If you ask for mild steel that is what you will get unless you are more specific OR ask what is available.

There is also what is known as "deep draw" steel intended for press operations where there is a lot of deformation of the steel. It is almost always in sheet or strip form and the tempered condition is as important as the chemistry. This is usualy a soft steel that is easy to work. All kinds of pressed steel auto parts are made from deep draw steel, oil pans, rocker covers, some body panels, frame components. The new "tin cans" with a seamless bottom are made from a deep draw steel.
   - guru - Tuesday, 08/17/04 20:00:07 EDT


You said, "Shelf life means its useful life expires on a certain date after manufacture. Like a bottle of milk next week or a box of cereal next year."

Boy, are you in for a rude awakening when you move to the Tropics! (grin)

Now, I might agree with a year's shelf life for untreated steel in the tropics, but milk is a few days (with luck)and cereal is a couple of weeks at best. Bring LOTS of airtight containers when you come.
   vicopper - Tuesday, 08/17/04 20:16:09 EDT

VIc, I try to buy milk close to home, run the AC and go directly home. But in Virgina it can be just as bad when the heat is in the mid 90's. The delivery trucks are not as cold as they should be and the walk in coolers in the store are also too warm. The "sell by" date usualy means you better not try to drink it the day before. . . Even with the high humidity here I have good luck with cereal. Where I am looking the maximum temperatures are lower and the humidity no worse. .
   - guru - Tuesday, 08/17/04 20:23:43 EDT

Coal bed,

I'm sorry, this forge has a "dip" in it like the one im trying to build. http://centaurforge.com/c536h.html
   - New blacksmith - Tuesday, 08/17/04 20:52:50 EDT

Forge Bed or Table: Newsmith, I'm with Ralph, if you are going to use "word picures" you need to use more words to put things into focus. To make things simplier I will use a picture.

Firepot image courtesy Kayne and Son
Typical firepot, tuyere with ash dump and clinker breaker. Image courtesy Kayne and Son

The firepot above is often used in new forges and as a replacement in old forges. A simple steel forge is a flat piece of steel plate about 24" to 30" (610 - 760mm) wide by about 36" to 40" (915 - 1015mm) long with a hole cut in it equal distant from the sides and one end. Legs support the plate at a convienient height. An improved version has an angle iron or flat bar lip welded around the edges to keep the coal from falling on the floor. This lip usualy has a gap or low place about 6" (150mm) wide on opposite sides of the fire pot for long work. Usualy the lip is 2 or 3" (50-75mm) high and the low place half of that. The larger the forge the taller the lip. The plate can range from 1/4" (6mm) up. The bottom of the forge is flat except for the fire pot. The lip around the edge allows for the storage of about a bushell of coal so that you can continualy push fresh fuel to the center of the fire.

The same configuration can be constructed out of wood and clay or mud and wattle, brick, stone or even in the ground. The above is a typical bottom blown forge fire pot for coal. Coke and charcoal need a deeper fire bed. Charcoal is also used in side blown forges and the British prefer to use water cooled side blast tuyeres for coal where in the US we use bottom blown. All these forges can be blown with a bellows, hand crank blower or electric blower. We were recently sent a photo of a Indian production blacksmiths forge that was no more than a hole in the ground with a blower feeding air from the side. A blend of 19th century and 15th century BC technology.
   - guru - Tuesday, 08/17/04 20:54:40 EDT

Coal Forge Hot Spot: Newsmith, The "hot spot" in a forge fire pot is from a few inches into the fire to about four inches (100mm) above that. In a large fire you may double these numbers. For rapid heating and forge welding you want your work in the "sweet spot" just above the hot spot. To get the sweet spot high above the firepot takes a huge inefficient fire. So you want cut outs to let you get your long work into the sweet spot without wasting fuel. The firepot above even includes cutouts in the pot.

If you are doing nothing but small short work or only heating the ends of bars there is no need for cutouts. Rivet forges typicaly have no cutouts.

A flat top forge with no lip avoids the problem but it restricts how much fuel you can store in the forge without it spilling onto the floor. A few smiths prefer the unobstructed flat top forge but they are far and few between.

See our plans page for drawings of side draft hoods that are much more efficient than the one shown on the forge you refered to.
   - guru - Tuesday, 08/17/04 21:09:38 EDT

Thank you Guru,

I forgot you could lay long steel stock on the forge. I was just worrying about the safety of doing so, besides I forgot you could lay a workpiece where it could touch coal as long it has coked right?
   - New blacksmith - Tuesday, 08/17/04 21:18:07 EDT

Ok, I just had to see what you guys thought about this. Wendy's superquench question was very interesting and gave the metallurgists a chance to shine, so let's see what you make of this:

Soldering in space

I'm at a loss to explain it, although it has to be some sort of energy transference issue. Anyway, it looked like a good candidate for discussion here.
   tanix - Tuesday, 08/17/04 21:40:34 EDT

Sorry, didn't realize the guru had html links disabled. The URL is:


   tanix - Tuesday, 08/17/04 21:41:15 EDT

Have wrought iron gate and the vertical support square stock poles seem to have bent from the gate weight causing sticking. How can I "bend" the upright supports to re-align the gates operation. I tried driving a wooden wedge between the gate and the closing side and that did not stay after taking the wedge out.
   Michael - Tuesday, 08/17/04 21:41:57 EDT

Mike, you will have to heat the gate to at least a low red and then pry it straight for it to stay. It will have to be supported while it cools, or it will just bend again.
   Paw Paw - Tuesday, 08/17/04 21:43:43 EDT

PPW, seems to me that it will bend again anyway..... at least not until teh root cause is corrected. Or am I missing something here?
   Ralph - Tuesday, 08/17/04 22:13:07 EDT

Newsmith, The coal forge fire is a world of variables. The bulk of the coal is raw unburnt coal, in a circle of about a foot the coal is coking down and varies from smoldering to fully coked. Inside of that you have burning coke and some raw coal that may have fallen in. The temperature varies from 1,000°F at the edges to 3,200°F in the center. When you put work in the forge you poke it through the mound of unburned coal into the coke and burning heart of the fire. One of the things you learn as a smith is to try to disturb the fire as little as possible but to keep advancing raw coal toward the center. However, when you poke a large piece into the perfect fire it usualy stops being perfect in short order and may have to be rebuilt every time you take a piece in and out of the fire.

Just about the time the fire is burning its best you get a couple good heats and then the fire rapidly degrades into a mass of clinker and ash. . .

All this varies greatly from forge to forge and coal grade to coal grade. This is "fire tending" and it is something you learn from experiance. You have to get a forge and burn some coal. After you have burned about a ton you will get the hang of it.
   - guru - Wednesday, 08/18/04 00:42:39 EDT

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