Machinery’s Handbook, Toolbox Edition 30th Edition (Ebook PDF)

Expanded metrology section, including v-blocks and micrometer, vernier, and dial calipers.
New fluid power section covering pneumatic,hydraulic, and vacuum theory and applications.
New powder metallurgy section, including additive manufacturing.
Even more useful specs, including tap drill sizes for Unified threads, reaming allowances for  drilling, mesh and grit sizes, rules for figuring tapers, and assembly with pins and studs.
Recently added information on sheet metal and presses, keys and keyways, shaft alignment, taps and tapping, helical coil screw thread inserts, metric screw threads, miniature screws, fluid mechanics, solid geometry, statistics,  calculating hole coordinates and thread dimensions, and distinguishing between bolts and screws.