James I make some knives as well as wood working. If you are going to make a plane blade from a file I could try to help you out if I can. My email is mookie1@autobahn.mb.ca Ron Petley Some of the knife making forums have talked about this you might find what you need by searching them. I know at this one it comes up often. http://www.bladeforums.com/forums/fo...play.php?f=741 Cheers Ron.
