Belt sander: Smoke escape!

Does it look like:

You could order a replacement switch:

1-800-444-3353

Prepare to wait ~30 - 45 days.

--Winston

(...)

--Winston

Hi Roy and others,

Thanks for the replies, but I had already checked HF's manual. I mentioned the NO cap-can as this is not a cap start motor. The switch HF shows is a simple two wire thing that I could easily manage to fudge around.

I have uploaded the pic to the drop box and you can see the switch has

4 connectors to integrate the coil thing into the circuit.

The main lead at the bottom is the power lead coming in and the Blue, Brown, Black and Ground lead goes to the motor.

The top two terminals on the switch (Red and Black) are bolted to the switch body so I assume they are carrying big current, the bottom two (White and Black) are riveted.

Unless I can get some other information I will assume that the Black/ Black make contact and the White/Red but can't be sure as the switch is fried totally.

Dave

OK, replying to my own postings.

I guess the switch had some different internal wiring. I plugged in a

10A DPDT switch I had lying around. The lights dimmed the motor ran. I put a clip-on meter and it was drawing 18+ Amps! Hasty turn off as a wisp of smoke curled out of the back of the motor.

looks like a scrap job to me unless I can find a cap start motor to fit in the available space. {sigh}

Dave

What you have there is a current activated relay which energizes the start winding on turn-on, then, once the motor is turning, the run winding current decreases to the point where the solenoid releases, disconnecting the start winding; this relay appears to be combined with the on/off switch. These relays are commonly found on sealed unit refrigeration compressors where it is not convenient to use a mechanically actuated start switch. Gerry :-)} London, Canada

You just might get away with separate components, go see your appliance parts shop. Gerry :-)} London, Canada

Thanks Gerald,

All a little too late, as you suggested, I think there was something in the switch that went with the relay. When I tried a conventional DPDT switch, got 18 Amp draw to the motor and shortly thereafter, more smoke. Ahh well. It served it's life well.

In fact I bought this at a HF sidewalk sale the used to have twice a year at Thousand Oaks. It had dropped-damage and I got it for about 15- bucks as I recall. I also bought one of the 4-1/2" x 7" bandsaws with drop-damage for 50-bucks, and it still goes today. It must have done

5,000 hours and still it keeps on keeping on.

So much for those HF knockers, some of their stuff is good, not all, but some. {grin}

Thanks for the suggestions anyway.

Dave

It might not be dead yet -- a short bit of smoke from the windings is not always a sign of it dying -- though if you let it run too long, it will die.

Two possibilities:

1) Bearings or drag somewhere in the mechanism, so the motor is having to work a lot harder than normal.

2) As someone else mentioned, a current relay which is supposed to switch off a start winding of some form is not working -- welded contacts or debris (swarf) keeping the armature from moving to break the circuit.

But -- it might be time to replace it anyway.

Good Luck, DoN.

Thanks Don,

The motor spins freely, I suspect the 18A problem was something to do with the switch/Relay combo. Maybe using just the start winding when I wired in a conventional switch.

The motor works fine if I just connect direct to the two main wires, it is just that I can't guarantee direction. {grin} Not all that good for a belt sander. The motor obviously does not have a centrifgual start-switch so I can't just add a start cap.

Perhaps you are right, time to replace it. Bummer. The best 15-bucks I ever spent.

Dave

Was the original switch provided with more than one pair of terminals? Is there a mechanical linkage to the relay? If neither is the case, I suspect that it is a problem with the relay itself. Either welded contacts or a build-up of sandings to keep the armature from moving, in which case it is applying power to the start winding full time -- or never.

So -- dig into the relay and see what isn't working there.

Worth a try with the relay at least.

Good Luck, DoN.