Wolf sander brushes.

[joe-90]

I've got a 100mm Wolf belt sander that I quite like. Very heavy. However, it's sparking like mad at the moment and I guess it needs new brushes. Anyone have any idea how much they would be to get fitted? The sander only cost £44 so I don't really want to spend more than about £20. Model WBS100.

 

[joe-90]

Forget about that one. The sparking is probably a sign of the armature being shot. New sander by the looks of things.

 

[big-all]

has it been stored in a cold damp shed over winter

if so the carbon brushes may have glazed over so a quick rub with emery or extremly fine file to remove the surface layer
and clean the commutator with silver polish or brasso
make sure all residue is removed from brushes and commutator
it will still spark a bit untill the brushes bed in again

 

[joe-90]

Yes it has. I'll give that a go - nothing to lose now. Cheers.

 

[theprinceofdarkness]

Just condemned an electric motor with the same problem. Before you clean the commutator, examine it very closely and make sure that the copper bars are all equally dirty and there are not a pair of contacts that are darker or smoky looking. What happens is that one of the 40 or so coils has a short in it and draws excessive current causing the sparking. If the machine stops with these contacts under the brushes it won't restart until it finds some working coils and contacts.
Frank