Simple Variable Speed Treadmill Motor Electrical Conversion 

Thank you very much for you kind comment! I'm glad you find the video useful.

You made my day! Thanks for letting me know that this video helped you. 👍

Excellent! Thanks for sharing.

Excellent! I'm so glad that your sander is working, that you found this video helpful, and that the video found you in Panama. Thanks for taking time to let me know.

Thank you very much!

Thank you, Steven.

What kind of treadmill was that? I'm scouting for a donor, not sure what to look for. ~2 hp would be ideal.

@@ptz0nPro-Form CrossWalk Advanced 525x. I think the motor said 2.4 hp. It's got some kick to it. I slapped a 10k pot and switch on it just like in this video and it works exactly as advertised.

Thanks, Chris! I'm glad you enjoyed the video.

Thanks for your comment, Joseph. It makes my day that this video helped you!

Thanks for letting me know you enjoyed the video. I hope your project goes well!

Thanks for the encouraging comment. I am glad you enjoyed the video.

How did the boat motor turn out?

Thanks for noticing that. I agree that it's hard to seen on video without the tape.

Thanks. I literally found this treadmill on the side of the road, which was just luck. I have found some deals on Craigslist that looked they would be good candidates for under US$50. Look for one that works but is need of non-relevant repair like a busted display, broken incline control, missing "key", etc. Also, before you drive to pick it up, do a search for repair parts for that specific model and make sure the one for sale has a comparable controller and motor. Some models have integrated controls and variable speed controllers that would be more complicated to convert than the one in this video. Good luck!

Awesome note. I'm so glad that this video inspired you. Thanks for sharing!

Careful with that. The mosfets on the controller board are chosen to handle the current of THIS motor. Bigger motors require more current and in the attempt to supply increased current, your mosfets would more than likely die.

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Thank you very much for the nice comment.

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Thanks! I'm glad you enjoyed it.

Thanks Mitch. I am glad you found it helpful.

I doubt that a potentiometer would substitute for a PWM signal in most cases. I'm actually surprised that it can here! A PWM signal should need only two wires. I *suspect* that the black wire is the DC hot, the white wire is common, and the red has the actual PWM signal, which is providing control information at a constant voltage. An oscilloscope would be definitive. Reproducing the PWM with, say an arduino or raspberry pi, would give very repeatable speeds.

No a pot can't replace a PWM signal. What may be happening is that there is a voltage goes up to the controller and then coming back, and the pot is varying the level of the voltage. If you have a true PWM and you feed it through a capacitor and resistor circuit you can create an analog level. This is how you could use an arduino board that is digital only to provide a signal that is more than just on or off, the resistor and cap are a low pass filter.

Thanks so much for your kind words, Andrew. My motor is externally cooled, and that's accomplished by the fins on the flywheel. If I run it without the flywheel, I'll need to come up with a separate way of cooling it. I'll either attach some fan blades to the tail end or just mount a small muffin fan that runs whenever the power is on. I presume that if the fan is connected to the motor, then the cooling will be proportional to the speed of the motor, so while there will be less cooling at low RPMs, it will use less power and therefore produce less heat. This is an assumption, of course, so definitely verify by monitoring temperature under load. Another thing to consider is that the motor may have less torque at lower RPM, so if you regularly want to use with a slow tool RPM, it might make sense to use gearing (or pulleys) to have the motor spin a bit faster while the tool is slower. Assuming the fan is attached to the motor, this should provide appropriate cooling. Although it seems to limit the benefit of variable speed, a lot of lathes have two or three ranges based on pulley settings, for this reason. I hope this is more helpful than vague. There are a lot of variables to consider.