Question about Skil 7 1/4" Magnesium "Mag 77" Wormdrive Saw With Twist Lock Model # SHD77M 72

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Sparking saw was notably sparking where the brushes make contact and tripping breaker. I changed the brushes but still sparking alot, the brushes I took out 1 was about 5\8 long and the other about 7\16 long. help thanks

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  • tuzzman656
    tuzzman656 Feb 22, 2013

    or just go to and buy and new armature.


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  • 14 Answers

Sounds like the stator is damaged. that is the shaft that the brushes rub on. unfortunately this usually means time to buy a new saw. since you really don't have much to loose, you can tear the saw apart and pull the stator shaft out and sand the copper area and smooth out any rough spots or nicks.Ultimatley you would want to chuck it up in a small lathe and turn it down a hair.this would ensure that you stay even all the way around. but most people don't have a lathe so just put it in a vise and take some 120 grit sand paper,preferably narrow strips about 1inch thick and start working your way around.

Posted on Jan 18, 2009

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