At the moment I have a Sieg C3, I like it, but maybe looking at getting a C4 or other larger lathe. I was then going to CNC it but had an idea:
I was thinking, If I were to remove all the gears that drive the feed screw, make a mounting and atatch a lets say 300W DC motor, now as my background is partially in MCu's etc, I was looking at getting a small screen, a propeller MCU and two methods of accuratley measuring RPM.
I input via some pushbuttons what thread i want (and is displayed on the screen), the mcu measures the spindle speed and from that works out what speed the feedscrew needs to be moving at to produce that thread. It would do all threads, It would be reversible, and when not screwcutting it can be used to produce a very fine feed for a great surface finish.
Cost would be the motor, motor controller (preferably I2C controlled), 2 methods of measuring RPM, a propeller develepment board, an LCD screen and something to house it. And then i need to make a mount and coupler and get the motor parallel to the shaft (or use belts i guess)