Built by engineers, for people who build things
Blog
Notes for the machine shop. Each calculator keeps its own address.
How the charts are kept
Where the tap drills, ISO fits and metal densities come from, and how a wrong number gets corrected.
Wire EDM allowance: spark gap and skim stock
Why the wire path is offset, what a skim is for, and why the drawing still sets the finished size.
M8 tap drill size: why it is 6.8 mm
The cut-tap drill for M8 × 1.25, why it is not 8 mm, and how a roll tap uses a larger hole.