I just bought one of those augers for $20 they work like a champ. The one I bought had a dull blade as well. I went to
www.strikemaster.com (they are the ones that bought out Osceloa Power Equipment Corp who made the Magnum 49cc III auger) They tell in the service section that you only sharpen the side that is away from the ice. Do not try to sharpen the ice side of the blade or it will not cut ice again. I took the blade off the auger and clamped it in a vice. I used a fine file and just followed the bevel that was already there. There are some burrs on the bottom of the blade and if you are carefull enough you could use a honing stone to remove them but I didn't bother the ice took care of that for me.
If you are not feeling up to sharpening it yourself Strikemaster has a blade replacement program where you send in your old blade and they will send you a sharpened one. I think the cost is about $9 plus shipping. Here is what you can do try to sharpen it yourself, if it doesn't work then get use the blade replacement program from Strikemaster to get a new one...
