When sharpening the blade, DO NOT USE A GRINDING WHEEL!   Instead use a bench sander with 120 grit belt, a couple of swipes/passes of the cutting edge along the sanding belt will provide a razor edge, it only takes a little finesse, when figuring the angle to hold the blade, place a coin on the sanding belt then rest the blade against the coin with the blade cutting edge touching the sanding belt that will give you the proper angle to hold your blade for sharpening