Dang, I have a Delta 12" bench planer and really like it too. I don't bother sharpening the blades. A set of blades only costs about $25 and are sharpened on both sides. They last quite a long time for me and when both sides are dull, I put in a new set. I make woodturning tools out of the old ones. If I were you, I'd look and see if a double sided set of blades were available for your planer and if they were reasonably priced......get them. It's like buying 2 sets.
I think if I had to sharpen my planer blades, I'd find a way to do it myself. Build a jig and use various grades of sandpaper that was glued to a piece of plate glass.
