Lathe motor arcing, swarf?

[Kram]

Motor has been arcing a little but yesterday got worse. Its DC brushed so I expect swarf trapped on commutator or brushes. Hope the windings are not damaged! Anyone had similar problem with a motor or know how to fix?

I had put some rubber sheet between the chip guard/back cover to isolate and reduce vibrations, worked great, but now there is a 2mm gap along one edge that I didn't notice that swarf has got in.

 

[M K]

I had this happen on a mini lathe before

Blew it all out with airline and it was ok again

 

[Anguz]

airline/hoover hopefully ok

 

[james butler]

Burnt commutator can cause this.
My old evolution saw would arc really badly then eventually cut out.
When I took it apart and removed the brushes you could see the burning on the commutator.
I got a new one under warranty which went the same way so got my money back

 

[Kram]

I am ****** off. The brush springs have week points crimped into them at 1/3rd and 2/3rd's down the length. One spring had broke into 3 peices the other was about to. Designed to fail. I have some spares from a router - not quite the correct size but the springs are perfect. Going to order some on ebay rather than warco.
Also double grub screws on the pulley. Only noticed the one, used a puller to shear the second

Thanks

 

[the snooper]

Those 3 closed coils look like they have carried the power to.me, so will have heated up and the heat will have destroyed the spring steel

 

[WorkshopChris]

Those 3 closed coils look like they have carried the power to.me, so will have heated up and the will have destroyed the spirit g steel

Yes definitely arced in places question is why. would be interesting to do a continuity test between the face of the carbon brush and the yellow coloured carrier.

 

[the snooper]

Was the wire still conceded to the carbon and brass connector

 

[Kram]

Closer look the broken spring has the defect almost every turn and twice on many turns, 180 degrees apart. I doubt the defect is caused by heat but it does look like it has got hot, and copper slightly discoloured. The copper connection is good on both, its the router spare that fell out in the pic.

Motor now runs perfect, smoooooth, quiet, no arcing.