I have a little Katsu router (bought after the recommendations on here) which normally gets very limited use. My current project required me to give it more of a workout than usual and during this it started to make a 'poorly' noise and then stopped. It wasn't particularly hot so I didn't think I had burnt out the motor and I checked all of the electical connections which were fine. I extracted the contactors to check them and one of them was coated with carbon dust which I wiped off. I re-inserted them and gave it a test and everything was good to go. This seemed like a fairly easy fix but it made me think that I should probably do more thorough maintenance. Can anyone offer advice about this? I did consider blasting it out with a compressor but I don't want to push the dust into areas it shouldn't be.