Just bought one of the little 12 volt Stihl chain sharp do-dads to sharpen my chains in the field, problem is that the little stones i buy for it "cake up" with metal shavings as i use it, also the stones seem to get hot, after i deal with both of these problems, the little stones don't do that great of a job. Is their something i can buy to put on / dip the stones in to keep them cool / from getting clogged up? I'm new to the saw chain sharpeneing scene, any help appreciated.