Sick of sorting out measurements for screws, or the numbering system for alloy sheets? Great Innovations’ chart keeps the important numbers handy. The chart has a ton of info, including the tap, drill, and stress area for screws, c’bore sizes, bolt grades, prefixes, fractional drill sizes, pipe threads, beam deflections, and Allen key sizes for imperial screws. Mechanical designers, machinists, and those working in CAD will love having all that info at their fingertips.
A plastic, sliding version of the chart can be purchased online for $24.99. If you’re worried you might lose it, consider the app version, available via Google Play and iTunes for $19.99.