Ok, I'm in the process of installing a servo 3 axis cnc kit on my mill / drill, which I originally thought it had 16tpi lead screws, but ends up being 10 Tpi screws. What is the formula to gonkculate the rpm speed / threads per inch to figure out what the IPM rate would be?
I planned on going direct drive, Does anyone see me having an issue in doing so ? Should I go more towards a timing belt reduction setup?

I'm working primarily with Aluminum, and looking for accuracy than ipm feedrate world records.

Thanks,
Art

Inches per minute feed rate = (motor rpm/red.ratio) / TPI
Al.

Many mills use 5tpi threads, so you're already twice that. It really depends on the torque you are developing and the max speed. By going to gear reduction, you are increasing the torque available and getting closer to your max speed. It's a tradeoff that requires more information to even start thinking about.