HELP! Craftsman table saw - weak motor!

[Ron]

My weekend project was to repair the deck stairs (16 steps, ~70
balusters) and my father-in-law gave me (for keeps : ) his (rarely used)Craftsman table saw when I asked to borrow it for the weekend.

It never gets up to speed, has no torque (I can stop the motor by hand(no blade attached)), and will trip the circuit breaker after a minute of operation (not cutting anything). I opened up the switch cover and found loads of sawdust; cleaned it out; still no good. Bypassed the switch, then the (internal) circuit breaker, finally wired the motor directly to the plug - still NG!

The windings in the motor have a good coat of fine saw dust, and I'm wondering if I can clean this out somehow.

I also thought about dismantling the motor case to get at the brushes, but don't know the consequences of breaking the epoxy (?) seals.

Any advice will be greatly appreciated. Needless to say, my weekend project is going slowly without the saw.

Thanks!

Ron

[Glen]

A few things here.
Be sure you've got 115v and not 60V, as though you've got a broken wire. Can the motor be turned my hand reasonably easy?
Remove any extension cords from the picture. If you don't have a meter try another outlet off a differant breaker, Like the washing machines outlet. Did it work afore ya got it. Does the motor get hot?

Glen

[Ron]

1)This saw was last used probably a year or two ago

2)The motor is easily turned by hand.

3)The motor gets hot to the touch pretty quickly.

Don't have a meter; I'll try another outlet. I don't see any indication of a broken wire, although one of the plug contacts has heavy pitting, so maybe it's not contacting when inserted; maybe I'll put a new plug end on.

Thanks for the advice Glen!

Ron

[BobN]

[font size="1" color="#FF0000"]LAST EDITED ON May-06-01 AT 03:04PM (CDT)[/font][p]Ron,

It's sounds like you have a problem with the windings in the motor. I would recommend taking it to an electric motor repair shop. They can check the windings for you and also help in cleaning the motor. If the plug is pitted there was a problem before. If you can stop the motor by hand it needs help.

After you get it checked out/fixed always try to keep it as clean as you can. Use a shop vac and if you have air, blow out the motor casing as well.

BN sends...

[Ron]

Thanks guys. Guess I'll be looking for a repair shop in the area.

Regards,

Ron

[Pastor Paul]

Is the motor direct drive or belt driven? With a belt drive, you can often buy a new motor for less than the rewinding cost. Two of my older brothers owned a motor shop back in Iowa, and we were amazed by how many people would rather pay more to rewind than to replace. Of course, this is not the case with all motors. Sometimes rewinding is the economical way to go.

Also, if it is belt driven, make sure your saw arbor turns freely. A bad arbor can mask as a bad motor because of the strain it puts on the motor.

If it is a direct drive saw, your only option may be rewind. I don't know if those motors are replaceable.

[Ron]

It's a direct drive, and the arbor turns freely. Once or twice, when started, the motor didn't seem to know which way to turn - it moved a few degrees in one direction then a few in the other, several times. It would also spin the wrong way on a couple of occasions. I thought I was going crazy - I reversed the blade a couple of times before I figured out the thing was turning the same direction every time it started.

Regards,

Ron

[Sonny Edmonds]

Hold everything!
When I got my Dad's saw rescued from Oregon, a nefew in law had tried to use it (unauthorized) and had wired the cord for 120 volt. The motor was hooked up for 240 volt.
Oh, it ran ok. But did egg-zackary what you discribe.
Took me a bit to sort it out.
Start back at your plug, set your saw up for 240 volt operation.
Wire the switch to switch bothe legs. Open the little "J" box on the motor and move your leads around for 240 volt operation.
WA-Zoo! The booger will run fine.
You just have to undo what you did.
You probably didn't hurt the motor yet. So stop fiddleing around and come at it with a logical approch.

A voice of experiance.

[Glen (Guest)]

Didn't think 220 was an option for those direct drive types.

G

[BobN]

Glen,
Several of these motors are 110/220. The preferred hookup is 220. It draws less current and runs cooler. Check your shop machines, if they can be run on 220 it would be wise to convert over. The biggest side effect is that the lights in your house and the neighbors don't dim every time you start up the TS, Jointer, or DC. You will have to replace the 110 switch on the machine with a double pole/double throw switch. Check the switch, some manufactures installed the 220 switch, but only used one set of contacts. The cost of a few 220 volt breakers and switches is well worth it in the long run.

BN