I have really never thought much about cleaning the collet on my routers, just wipe them out and go.....
Then when I got my Precision Collet and Nut for the PC 75618 it came with a bottle of ColletCare and instructions on how to use it.
It states you should do it every week but I will admit I don't do it every week but I do clean it often, like ones a month.
I found that after I stated using the ColletCare and cleaning my collets they sure work better. I had cleaned the Precision Collet one of two times and then I thought how about my other routers.
Wow, I could not believe how bad they were, the little Dewalt 611 was a mess, after I cleaned it up with the ColletCare it was like a different collet, bits went in and out much easier and they tightened much easier. The collets on my Bosches were not much better, rust and junk in the spindle and on the collet.
I have now cleaned all the collets on my routers and keep them clean and they work so much better.
I have no connection with PreciseBits at all, I just own one of there great collets.
Here is their write up on maintenance of the collet and spindle.
http://www.precisebits.com/tutorials...eprocedure.htm
You can get a bottle of ColletCare for about $14 and it last for years.
http://www.precisebits.com/products/...colletcare.asp