I would take it apart, blow out with air, use brush,etc. Stay away from=20
water, maybe use a little alcohol. You might be able to clean and=20
regrease the bearings, if not cleanliness is very important. If the=20
commutator is smooth, but dirty, could use 600 grit wet/dry paper to=20
polish. If rough, I have chucked in a drill, and used a file to clean=20
up, but if the insulators between the copper bars are raised or there=20
are copper bridges, that needs to be removed. Check the brushes, springs=20
and replace if need be. The brushes should fit the radius of the=20
commutator. The best would beto take the armature to a shop to turn the=20
commutator. If the brushes don't have a jumper wire inside the spring,=20
might need one to minimize arcing. The tear down is as much inspection=20
as it is maintenance.

On 5/22/13 11:30 AM, veegee wrote:
> Hi all, I have acquired some old battery power tools (drills, saws,
> etc.). They have been thoroughly exercised in their life, but they're
> working fine and nothing is broken. Parts are solid metal where they
> matter, and these will last at least a couple of more decades if well
> lubricated and maintained. They don't make 'em like they used to.
>
> The only problem I see (and unfortunately, smell), is that the DC
> brushed motors are creating a LOT of sparks and "smoke". That
> characteristic smell of old, sparking DC motors, containing lots of
> ozone, that burns your nose hair out. The motor itself is running well,
> despite this issue. The sparking is so bad, that looks like there's a
> small incandescent lamp inside the motor when it's on.
>
> The motors themselves are sealed pretty tight, apart from the vent
> holes, which are big enough to stick a cotton swab through. Further
> disassembly would require prying metal and most likely, damaging the moto=
r.
>
> What's the best way to clean the motors without taking them apart or
> damaging anything inside? I assume the sparking is caused by carbon and
> dirt buildup at the brushes.
>
> Would washing with soap and water, and drying promptly do the trick? Or
> is there anything that could get damaged inside?
>
> How about spraying some WD-40 at the brushes through the vent holes,
> then washing with soap and water?
>
> My only concern is stripping the bearings of their grease, but is there
> anything else that could go wrong?

--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.