Just an FYI. I've hand sharpened my chainsaw many hundreds of times over the past 15 yrs, but one month ago I got a sharpening stone form my Dremel tool. What a relief! It's so much easier than wrestling with the saw and sharpening by hand. Saw gets nice and sharp, with a minimum of physical effort, and in less time than handsharpening. Here is Dremel's video on it.