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Jack Hovanec
09-25-2019, 11:15 AM
I know this is a woodworking question, but I figured I'd start here. I bought a motor to replace the one on a cheap taiwan edge sander I bought at auction with a blown motor. Brought the new motor to the shop, plugged it in, and it runs in the wrong direction. Bummer....
I was wondering if anyone knew of a way to reverse the direction of these motors. Its a single phase 240V capacitor start/run motor that came off of a grizzly dust collector. I guess it wouldn't be the end of the world for my edge sander to run in the wrong direction, but its worth a shot. I know that you basically just need to reverse the polarity of the starter winding if its possible, but I have no idea which wires to switch.
Here are some pics
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Rod Sheridan
09-25-2019, 11:48 AM
It's hard to tell however you would need at 4 leads coming out of the motor in addition to the capacitor leads for it to be reversible.

From what I can see, your motor is not reversible.

If the belt direction is backwards on the sander, dust collection will be ineffective as well the work supports........Rod.

Jack Hovanec
09-25-2019, 12:03 PM
I think I could probably modify the dust shroud to work in reverse... Do you have any idea if I could access the other two wires by opening the motor up? Maybe its not worth the trouble.
Jack

Rod Sheridan
09-25-2019, 2:45 PM
I think I could probably modify the dust shroud to work in reverse... Do you have any idea if I could access the other two wires by opening the motor up? Maybe its not worth the trouble.
Jack

My experience with electric motors is that if they didn't bring the leads out, there aren't any leads.

The winding wires would be probably be soldered or use a compression connector so you cannot have access to them.........Rod.

Bradley Gray
09-25-2019, 2:59 PM
If it is possible to mount the motor at 90 degrees to the sander pulley you could run it with a 1/4 twist in the belt. One of my lathes is set up this way to make it reversible.

Eric Danstrom
09-27-2019, 6:24 AM
All single phase ac motors can be set to run in either direction. It's a matter of the starter winding's polarity. (The winding connected to the centrifugal switch.) If you're not sure how to do it, check with a motor repair shop. I have some fractional HP motors that have the diagram on the outside motor plate.

Curt Harms
09-28-2019, 9:25 AM
IME motors that can be reversed easily have at least one group of wires that are connected to each other but not to any power source. You don't have a group of wires like that so no, it probably is not easily reversed. Could it be made reversible by someone who knows what they're doing? Maybe but it'd likely be easier/cheaper to buy another Asian motor that is reversible.

Bill Bukovec
09-28-2019, 9:59 AM
Have you called Grizzly?

Bill Dufour
09-28-2019, 10:46 AM
You will have to dig into the windings and find the buried leads to the start windings. Then you will have to attach longer leads and bring them out to the wiring box. You should re-dip the coil afterwards to keep the windings in place.
Bill D

Bruce Wrenn
09-28-2019, 9:10 PM
Definite purpose motors (blower, air compressor) generally aren't reversible, in my experience. Simply no need to add to cost of motor for something that will never used.