I thought I would share one of the most useful modifications that I have made to my Harbor Freight wood lathe. By adding a lower range of speed control to my lathe I am able to turn large, out-of -balance bowl blanks.
The factory speed range for this lathe is 600 to 2400 RPM. Trying to turn even small, out-of -balance bowl blanks at the slowest speed of 600 RPM can be quite unnerving. This modification allows me to adjust the speed from 0 to 2200 RPM.
I replace the factory ¾ HP AC motor with a ½ HP 90 Volt DC motor. I wanted a motor with more horse power but I could not pass on the price, it was free.
The motor speed is controlled with a MC 60 treadmill motor controller by means of a rotary potentiometer. I’ve added a push button on\off and forward\reverse switch. I purchased the controller on EBay.
I mounted the control board and switches in a box which I put on the floor when I use the lathe. This allows me to use my foot to turn the motor on and off.
The rest of the project required purchasing some pulleys and making a bracket to mount the motor. I replaced the reeves adjustable speed pulley with a standard pulley. The outboard side of the lathe spindle is 24mm in diameter. In researching this project I found that this same spindle is used by a number of different lathe manufacturers. Jet, Grizzly and others use the same reeves pulleys and spindle in some of their wood lathes.
I’m very happy with how the project turned out. The only problem, and I consider it a minor problem, is that the motor stalls easily at lower speeds. I have less stalling as the bowl balances and I increase the speed.
Thanks for reading.
-- Muntzie - Marietta, Ohio