Shopsmith Forums

I just rebuilt my 1950's Greenie with the guts from my Father's 1980's era (he just upgraded to the digital controller). Replaced everything including the motor, sheaves, quill, speed adjuster and switch.

The rebuild went fine - everything is back together and I can rotate the works by hand with the disc sander attached. But, when I power up, it just hums for a moment and blow the circuit breaker.

Anyone have any ideas I can follow up?

Thanks, Rob

What size power cord do you have attached to the motor? And how long is it? That would be the first thing I would check.

raweber wrote:I just rebuilt my 1950's Greenie with the guts from my Father's 1980's era (he just upgraded to the digital controller). Replaced everything including the motor, sheaves, quill, speed adjuster and switch.

The rebuild went fine - everything is back together and I can rotate the works by hand with the disc sander attached. But, when I power up, it just hums for a moment and blow the circuit breaker.

Anyone have any ideas I can follow up?

Thanks, Rob

Does the motor run with no load? Just remove the drive belt to check this.

I am assuming the motor shaft/pulley is turning when the disk is rotated.

The Motor start switch is probably clogged by sawdust dislodged by handling.

Blowing it out with compressed air(from the back end, not the shaft end) MAY clear it.

A better approach would be to disassemble the motor and really give it a good cleaning.

At this point I would concentrate on only the motor.

If you can, power on testing is best done in a manner that allows you to disconnect faster than the breaker if it merely 'hums' when power is connected. That humming is an indication of no turning which will lead to over heating the run windings.

BTW what is the motor manufacturer?

Good advice above. But I thought of something else. Is the speed dial turned all the way down to Slow, or is it on Fast?

heathicus wrote:Good advice above. But I thought of something else. Is the speed dial turned all the way down to Slow, or is it on Fast?

Hopefully the speed dial is at low speed setting at start up but if it is not, the motor should still do more than just hum. There should be a noticeable turning of the blade/shaft until the breaker kicks.

heathicus wrote:Good advice above. But I thought of something else. Is the speed dial turned all the way down to Slow, or is it on Fast?

I keep overlooking that! I never had to do that! Starting at 'fast' with the sanding disc mounted can be interesting.


OHH OHH maybe that IS the scenario! ?:p

All right - I pulled the drive belt - still no go. For the record the motor is an Emerson C55DDR-2015. I can't believe it's anything too exotic since it's what came in my Dad's stock Shopsmith thirty years ago.

Now the twist - it's started blowing the breaker whether it's turned on or not, which makes me suspect the switch. My car's in the shop right now but when I get it back later today I may make a run down to the hardware store and see if I can get a replacement switch.

To answer a few other questions - the power cord is the original that came with my Dad's Shopsmith that he's used for the last 30 years. It's in really good shape.

If a new power switch doesn't do the trick, my next stop will be the take the motor out and take it apart as much as I can to clean it out. There is a lot of fine dust visible inside it.

Thanks for all the help. I'll report back what happens.