Gord Graff says 0.005 inch precision needed for tenons.
I propose using 0.001 inch units in OpenSCAD.
youtube Gord Graff - Accurate Woodworking Through Precise Measuring Techniques
0.005 inch precision for tenons.
youtube Woodomain - Jeremy Broun - Why I never use a ruler - Woodworking with Jeremy Broun
- measuing sticks
- screps of paper
youtube The Jeremy Broun Routing Omni Jig