Motors

[Welderpaul]

Yet another knackered mag drill. Someones been using it to drill out plasma-cut holes. The brushes were burnt away, but otherwise seemed ok. I changed the brushes for new ones, but when i fired it up, the brushes sparked like hell. Thought it might be just while they bedded in, but the new brushes have amost worn/burnt away after only a short period of use.

Anyone know why this may be? Is it terminal?

 

[the snooper]

it could be a sign that the coils are burning our or the commutator could want refacing but probably the first

 

[Hitch]

Rotabroach.... puma by any chance?

 

[brightspark]

Yet another knackered mag drill. Someones been using it to drill out plasma-cut holes. The brushes were burnt away, but otherwise seemed ok. I changed the brushes for new ones, but when i fired it up, the brushes sparked like hell. Thought it might be just while they bedded in, but the new brushes have amost worn/burnt away after only a short period of use.

Anyone know why this may be? Is it terminal?[/QUOTEyes they have knacked one of segments and windings out on the armature .if its still being run for a while the feild coils will be shot as well

 

[Welderpaul]

Its a Makita drill body. Looks like its one for the repairers then.
Thanks

 

[pedrobedro]

If you have some brushes spare try cleaning the slots in the commutator with a thin file then wrap some 1000 grit round it and spin it with your hand to smooth it off. I had a grinder that ate it's brushes and treated it to this and it's run for 3 years now on the last set I fitted.