# How Powerful Does a Disk/Belt Sander Need to Be?



## ForeverLearning (Aug 27, 2019)

I am looking at a few used treadmills to get a scrap motor. 

So far there is a range of 0.8HP to 3HP DC motors.

Would anything within this range be suitable for a a 10-12" disk sander build or a 2x72" build? 

Cheers!


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## DSChief (Aug 27, 2019)

1 to 1 1/2 should be fine, speed control is more important. Too hi a feet per sec. can burn an edge in a New York Heart beat.
I'm running a KBDA 27D & keep Motor RPM in the 800 to 900 rpm range


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## ForeverLearning (Aug 27, 2019)

Thanks! 

That should be fine, I will likely go for the upper end HP motor on the treadmills and hopefully will be able to keep speed control from treadmill and just figure out rpm/fps.


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## daizee (Sep 9, 2019)

Trick with the treadmill motor is cooling and dust protection. Motors used on belt grinders are to the TEFC spec: "Totally Enclosed Fan Cooled". I recommend 1HP minimum. I have 1.5HP and get about 1-1.25HP out of it on 120V. Upgrading to 2HP VFD on 240V. soon. If you're in England, surely everything available will be powerful enough on household electricity.

Let us know how it turns out, I have a disassembled treadmill motor and controls stashed away for just such a project. I kept the dashboard, because I can't wait to crank my grinder up to "Fat Burn"!


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## suntravel (Sep 9, 2019)

I am running my 2x72 with 3HP 400V and VFD, works well an has enough torque on lower speeds.

Regards

Uwe


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## Tim Rowland (Sep 9, 2019)

I run a 2hp Baldor motor with VFD on 240v, it is plenty. I think 3hp for a 2x72 is overkill. 
As stated above the enclosed motor is the important thing. Metal dust can cause all sorts of issues.


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## suntravel (Sep 10, 2019)

Yes should be dust and moisture proof, also the VFD...



























Regards

Uwe


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## ForeverLearning (Sep 10, 2019)

suntravel said:


> Yes should be dust and moisture proof, also the VFD...
> 
> Regards
> 
> Uwe



What's the FRL for? Are you spraying water or air on the belt in that picture?


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## ForeverLearning (Sep 10, 2019)

daizee said:


> Trick with the treadmill motor is cooling and dust protection. Motors used on belt grinders are to the TEFC spec: "Totally Enclosed Fan Cooled". I recommend 1HP minimum. I have 1.5HP and get about 1-1.25HP out of it on 120V. Upgrading to 2HP VFD on 240V. soon. If you're in England, surely everything available will be powerful enough on household electricity.
> 
> Let us know how it turns out, I have a disassembled treadmill motor and controls stashed away for just such a project. I kept the dashboard, because I can't wait to crank my grinder up to "Fat Burn"!


Currently waiting on a potentiometer and a bridge rectifier to be delivered. Once that's working, frame work will be ordered for a weld free 2x72. I can see this taking a couple months at least but hopefully shouldnt take too long


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## suntravel (Sep 10, 2019)

Air and a special fluid for MQL, not as good in cooling like flooding with water, but less mess and better surface.

Regards

Uwe


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## Jmcc (Sep 20, 2019)

I have 3 hp 220 v motor with a vfd
No such thing as overkill when it comes to motor size unless we are talking way bigger motors


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## ForeverLearning (Sep 20, 2019)

Well my 10kw potentiometer arrived, my bridge rectifier is here so I will wire up this weekend and see how it goes!


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## Jeb Taylor (Oct 8, 2019)

suntravel said:


> Yes should be dust and moisture proof, also the VFD...
> 
> 
> 
> ...



That is the coolest grinding wheel ever made.


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## Donald Roe (Oct 13, 2019)

I’m running a 2x82 2HP VFD at 120v with a multistage power conversion and options to run higher voltage for a higher torque and higher rpm.



ForeverLearning said:


> I am looking at a few used treadmills to get a scrap motor.
> 
> So far there is a range of 0.8HP to 3HP DC motors.
> 
> ...


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