Hammer Eye Dimensions:
For punches and handle driftsHammer Eye Dimensions:
I found a hammer handle manufacturer's list of dimensions and will extract a chart (eventually). A 1.5 to 2.5 pound hammer has a 7/8 x 5/8" oval eye. A 3 to 4 pound is 1" x 3/4".
U.S. Department of Commerce, Forged Tools Simplified Practice Recommendation.
For oval handles.
Handle eye width = 40% of hammer width
Handle eye length = 125% of eye width.
Tolerances +1/16" - 1/32" max.
Tapered sledge eyes taper to center 4° on long axis and 3° on short axis. This is for punches and finished holes.
Note that the above is for a true oval. Check your drafting book or Machinery's Handbook for how to lay one out. There are also straight sided handle holes with round ends (milled). Thess are US standards I am sure European standards are different.
- guru - Tuesday, 11/14/06 01:04:50 EST
My information is not as exact as that in the Guru's response. But anyway, here goes based on my experience.
We have talked about this. If I buy a hammer handle, I get the "16 inch machinist's handle". The eye-end will give you an idea as to dimension. Harcourt's "Elementary Forge Practice" shows the initial punched OVAL hole measures 5/8" x 7/8". After drifting the hole has a 1" length by an 11/16" width. Nothing is written in stone. 5/8" x 1 1/16" is not unusual. An old rule of thumb for hand forged hammers is the eye length is twice its width. Many a hand forged hammer in the U.S. had an oblong eye; ie., the eye had two parallel sides in length. The ends were half round. It is easier to forge and cold finish such an eye when compared with forging an oval eye. It is easier, because you forge a tapered rectangular section and then swage and cold finish the ends.
The initial punched eye I judge to be about 2/3 the size of the finished eye. My drifts are about 8" to 9" long for a 2.5 pound cross peen. The small end should just enter the eye when drifting. I drive the drift in about three quarters of its length, and I drift from both sides. While the drift is in, flatter the side bulges.
If the drift is 8" long and the small end is about 2/3 the finished eye, then 6" up from the bottom will be the finished eye size. The drift has a full taper top to bottom. It is not driven all the way through from one side. Drifting from both sides is advantageous. It will give the eye a slight hourglass shape, the latter being desirable for the insertion and wedging of a wooden haft.
Frank Turley - Tuesday, 11/14/06 01:28:11 EST
Handle Eyes: There are several standard shapes. The main ones are the oval (a true elipse), the round end rectangle and the rectangular or adz eye.
The oval is the standard eye for most blacksmiths hammers and sledges. The round end slot is less common and more suitable to being made on a machine tool like a milling machine. The square hole like the oval hole is punched.
I see a lot of Chinese hammers made from a block of iron/steel with a round drilled eye . . . (worthless).
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