I'm thinking about getting one of those small mini-mills at HF, Grizzly, Homier, etc. and converting it to CNC for machining PC boards. The ones I've seen at HF have X-axis handwheels with 62.5 graduations. One revolution moves the table 0.0625". 16 revolutions moves the table
0.0625*16=1". So it seems the threads on the X-axis leadscrew are 16 TPI. But I thought the strange 62.5 graduations was because the leadscrew was actually metric and retrofitted with a strange handwheel for the US market. 0.0625" converted to metric is 0.0625*25.4=1.5875mm. If the leadscrew was metric, shouldn't one revolution be some nice round mm number? Am I misunderstanding something? I plan on adding one of those cheap digital linear scales so it doesn't really matter, but I just want to make sure.- posted
20 years ago