Thought I'd pass this potential tip along for sharpening mortising chisels. If you've got a lathe with a 4-jaw scroll chuck, that makes a handy holder for a mortising chisel. Run the lathe at slow speed and use a cone tip in your Dremel tool. A light touch works best and really get things sharpened quickly and accurately. I tried two different types of chucks and they both worked well enough to get the job done rather quickly. Obviously, care must be taken, but wood turners should be accustomed to handling sharp pointy things.