[Bantam175]

I’m building a cnc lathe and I have my X and Z axis working, but I now want make it capable of cutting threads.

1: How do I connect a rotary encoder to mach3, is it done through the breakout board as I don’t seem to have a input option for spindle speed?

2: Can I use the rotary encoders sold on ebay, see link or will I need to make my own?

but my main question is, how do I connect the RPM pulses to MACH3?


Encoder 6mm Shaft 600P/R Incremental Rotary AB phase for Length Measurement | eBay

[DICKEYBIRD]

Unfortunately Mach3 won't work with an encoder unless you have an external motion controller (Smooth Stepper, CSMIO, etc) If you're using the parallel port, it will only work with a single pulse/rev device, usually opto sensor & slotted disc. I use a CNC4PC C3. Cheap & works well.

Threading with Mach3 has been challenging for me because my spindle drive wasn't powerful & steady enough for cutting threads in steel over 16mm dia. Had to build a 1:4 reduction belt drive to get it to work.

[Al_The_Man]

You could also look at Kflop Kmotion.
Al.