I'm using a PMDC motor from an old treadmill. The controller in a treadmill does a soft start, that is it always starts up at zero speed. This is very bothersome when working on a lathe so I need a controller that starts up at the last speed used. I'd like to build a PWM controller for the loads involved but since I'm really not knowledgeable in electronics I don't know how to select the correct components. There is lots of stuff online but usually for little motors.

I've copied one design- converting AC power to DC using a bridge rectifier. I varied the AC and was able to get a corresponding variable DC, but it would not run the motor. I know motor works because I can run it with my power drill batter.

I've take a power supply from an old computer so I have a source for DC and it will run the motor very slowly. Not sure how to speed it up or how long the power supply would last with the motor loaded.