Reading this,I think back to when I started buidling wheels. There were no spoke calculators. There were barely calculstors, definitely no internet.

So we calculated spoke length by hand.

I sometimes think that why 4x 36h builds were SOP. Since, the spoke went to the centerline, it was half the diameter, allowing for the nipple, plus about 1mm for each 10mm of flange offset, plus 1mm for good luck. When I was building different patterns, simple measurements and basic arithmetic worked fine.

From time to time, I still use the graphite calculator I've trusted for half a century.