WFF2001 Commutator wear – too much?

[drbob]

Hello forum,

I recently replaced the brushes on our 14 year old Bosch WFF2001GB/01, one of the brushes was down to around 1 cm and the commutator is pretty worn:

I cleaned it as best I could with a pencil eraser and some 800 grit sand paper but this didn’t remove all the carbon. The new brushes also sit in the significant groove created by 14 years of use.

Should I be looking to get a new armature instead? Are they even available for this motor? I’ve ordered a commutator cleaning stick in the hope that will allow me to clean it up properly. The motor does currently run with the new brushes but it sounds like it’s sparking a lot.

Any tips/advice would be much appreciated.

—
drbob

[Martin]

Re: WFF2001 Commutator wear – too much?

Careful application of a commutator cleaning stick will certainly tidy up the deep seated grooves on the commutator and leave it still very usable. It would also help to dismantle and clean the whole motor with a high pressure air-line or spray it liberally with WD40 in order to remove all traces of carbon dust prior to re-installation. 🙂

[drbob]

Re: WFF2001 Commutator wear – too much?

Thanks for your reply.

Should I be looking to run the motor on the bench to properly clean it with a comm stick, or would manually rotating the shaft whilst holding the stick in place be enough?

[Martin]

Re: WFF2001 Commutator wear – too much?

drbob wrote:Should I be looking to run the motor on the bench to properly clean it with a comm stick

That’s favourite. :tup:

[drbob]

Re: WFF2001 Commutator wear – too much?

After some thought I’ve decided to leave it alone.

I believed the motor was sparking due to the crackling sound coming from the machine as it turned – however that seems to have stopped now (I think it may have been a symptom of the brushes bedding in). I’ve since run it with the back off and could see no sparking.

When I went to pick up the comm stick from a local carbon brush manufacturer the kind gentleman there took a look at the above photo and recommended that unless it’s sparking a lot, I leave it be.

Given my limited knowledge of these things I’ve deferred to his judgement. I also took one of the brushes out and it seems to be bedding in quite well (smooth and shiny over 95{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} of it’s contact edge, small chip in one corner)

[Applianceman2010]

Re: WFF2001 Commutator wear – too much?

You ar quite right these motors spark and cracle and wine like hell sometimes,then after a few washes it calms down :tup:

[nomadPaul]

Re: WFF2001 Commutator wear – too much?

If i get a lot of noise , i always run the machine on a couple of empty high speed spins to help the brushes bed in . Sounds like you’ve inadvertently done exactly this .

[Author]

Posts