Dewalt DW708

[Shadelady]

Hello folks i am just goin to jump right in. this saw of mine, i love it. however i think i overheated the motor- was smoking after last use. i honestly hadnt noticed it heating up. anyhow, the brushes look pretty good. i took off the outer black cover and looked at the armature and there is some mild scoring on it. so mild i would call them scratches. i attempted to remove the larger yellow cover and it seems stuck / screwed on somewhere i havent found.
at the present moment the motor runs, its just a sparkier than what i remember it being and it doesnt quite sound right- cannot put my finger on anything sound-wise as i am not too keen to run the saw the way it is. my inclination is to clean the armature as much as possible and try again.
i talked to a DeWalt rep and they told me to just run it and that if it had just over heated that it would "wear back in"

what woudl you do if it was your saw?

btw this is a fantastic site!!! thanks for any and all replies in advance.

[UtahAV]

Hi Shadelady,

Them arcing could be caused by insufficient contact between the brushes and the commutator or by a bad armature. If the brush is nor sliding easily in the brush holder it may stick and then sit a fraction of an inch above the commutator rather than pressing against the commutator. The electricity will then arc between the brush and the commutator.

Due to the smoke that you observed coming from the motor I would suspect that you have a damaged armature. If the motor does not receive the proper amount of current, either from working the motor harder than what it was designed for or by an extension cord that is too small of gauge for its length, it will heat up and damage will begin. The smoke you saw is usually from the insulation on the motor windings overheating and melting or burning. Once the insulation burns away shorts develop in the windings which create arcing at the commutator. A growling noise from the motor is also usually associated with this type of damage. The damage will be to the armature, the field or both. If the damage is not visually obvious then you will likely need to have the armature and field tested by a motor shop to determine which is bad. The motor shop will have the specialized tools needed to perform the tests.

I hope this helps!

-UtahAV
-Mark

[Shadelady]

Mark- will take a look at how the brushes are seating- lets hope thats all it is!!! i am in a tiny town so i am not sure i'll be able to get the armature tested.

thanks for giving me direction!!