I have a mains powered Dremel multi which hasn't had very much used. After cutting a square hole in a metal locker it now runs roughly and doesn't go as fast as it should - I've clearly damaged it by what I used it for.
Is it likely to be cured by fitting a new set of brushes?
Depends what's actually wrong with it ..
I'd take it apart and just have a look, it could easily be some swarf caught round the chuck area somehow that's causing the lack of speed and roughness!
They don't take much effort to stop them, so when cutting keep the blade speeds high and use a light touch, which also reduces the size of chippings/swarf and reduces the chances of fecking things up.
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