In a world where change is constant Machinery's Handbook has been a relative constant. While there is change in every new edition it is not so great as in the last edition. Change comes slow to such an encyclopedic reference published for nearly a century. New editions have been published every four years to keep up with changes in knowledge and technology. As technology changes faster books like Machinery's Handbook must change with the times. The first 80 years of the handbook showed the very gradual changes in technology but the last 20 has seen revolutionary changes. One of the changes in this edition was to combine the divided indexes of the previous volume into one as it should be. This edition also has the most pages ever with 11 more than the last edition. There were also 17 pages taken up by the Index of Standards and Index of Interactive Equasions which were removed making a total of 28 more content pages. I thought the Index of Standards was handy but the Interactive Equasions is a CD-ROM feature that does not need to be in the book. These are the picky decisions an Editor must make to add new materials. One of the new sections in the 28th edition is motor alignment. There are a dozen diagrams and explanations. Old diagrams that were a tad raggedy for the modern era have been redrawn in CAD and are much clearer. The welding section includes details on MIG pipe welding and LASER cutting and welding with wonderful clear line illustrations. Of course major rewrites often invite new errors. See An Error below. I was also disappointed that articles on vibratory finishing and tumbling are absent from the section on finishing. But there are many new technologies that need coverage and editors are often forced to make hard decisions. For a couple decades the end papers were used as a "Ready Reference Index" or quick index. Then they reverted back to plain. The new 27th edition has handy Conversion Factors charts from Cosworth. The front (at left) has Area and Volume conversions, the back Force, Pressure, Stress, Energy and Mass. Click for detail. Perhaps this is a sign that the engineering world is recognizing that there may always be more than one standard of measurement and that conversions will be with us for a long time. Thumb Tabs have been one of Machinery's constants for most regular users. You could pick up any edition and go to a familiar topic. The 28th edition thumb tabs are the same as the reorganized 27th edition. However, the quality of the tabs has once again dropped since their reintroduction. The cuts are short, not tapered and the tabs difficult to read due to color and alignment. 27th and 28th Ed. Thumb Tab Topics (12) Math & Mechanics Properties of Materials Inspection Tooling Machining Manufacturing Fasteners Threading Gearing Machine Elements Units Index A Repeated Error: This error was reported in the review of the 27th edition and repeated in this one as well. The first sentence of the welding section states. Welding of metals requires that they be heated to a molten state so that they fuse together.  . . . In fact metals can be welded at room temperature in a vacuum and are commonly welded at much less than the melting point while in the plastic state. Although the blacksmith's solid state forge welding may be considered archaic as an industrial process, there were several pages on the subject in the first dozen editions of Machinery's and it was still defined as a process up through the 18th Edition. Solid state welding is still a production process in making pipe, tubing and clad metals. Further Comment: This error (more of omission than fact) goes back as far as the 17th edition (maybe 16th) when the article on welding was re-written to place less emphasis on forge welding. The original welding article describes the forge welding process as occurring when the metal becomes "soft and plastic" (5th maybe 1st through 15th edition). This is correct. The handbook has always been one of my favorite references. For anyone in the mechanical trades it is an indispensable source of knowledge, facts and figures. It includes everything from volume and beam stress formulas to the periodic table and how to apply SI metric standards. Need to know the density of oak or mahogany, or how about the constituents of forging brass? Machinery's has it all!

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Large print edition $115.95
CD-ROM $94.95
ISBN 9780831128005 and ISBN 9780831128012 (large print)

• Machinery's Handbook Collective Review
• Machinery's Handbook 27th Edition
• Machinery's Handbook 27th Edition CD-ROM
• Machinery's Handbook 1st Edition Commemorative Reprint