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Old 03-09-2013, 12:49 PM
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cmac2012 cmac2012 is offline
Renaissances Dude
 
Join Date: Dec 2004
Location: Redwood City, CA
Posts: 34,120
Quote:
Originally Posted by Rob Pruijt View Post
If an electric motor starts smoking a coil has shortend.
Unfortunately that is not repairable, you can only replace the motor or the saw.

The sympoms of a worn brush are:
1- some lighning effects
2- power loss

IF the brush doesn't make good contact it can't conduct enough electicity, so it can't smoke (required a lot of current)

A shortend coil gives sunndenly a lot of (not very healty) smoke, and melts the brushes.

Electic tools for home use are not made for contimuous use, usually 10 minutes use and 50 for cooling down. Professional tools have a much better work cycle.
If you overheat them they will burn out.

Rob
Not sure what the coil is. My only clue on the smoking was the major sparking coming from the commutator area - this I discovered after it started smoking. Also, the burnt and melted plastic in the brush holders. I hadn't been using it that long before it started smoking. Maybe 10-15 minutes.

I have gotten a lot of good use out of this saw. I should have been more astute about checking the brushes sooner. I'm in the process of checking my other major tools.
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