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View Full Version : what kind of grinding wheel for chisels?


Harry Thornton
04-23-2005, 12:13 AM
I have one of your tipical two wheel grinders. I have a wire brush on one side and a course grinding wheel on the other. The motor is 3450 rpm, which seems too fast to me but I got the grinder for the low, low price of free. What grinding wheels would you guys recommend for sharpening chisels?
Jim Becker
04-23-2005, 9:10 AM
None, if they are bench chisels. Bench chisels should not be sharpened on a grinder like that...too much heat and too coarse for other than reshaping something that got really whacked for some reason. Water stones (a few folks prefer oil stones) or the "scary sharp" method that uses paper on glass is where you want to go. Honing the edge during use is quick, easy and sure on an 8000 stone.

If you are talking about turning tools, that's a different story. HHS turning tools get sharpened very frequently. For this job, I prefer a 100 grit wheel, but they are harder to find. In most cases, you'll find an 80 grit wheel on one side and a 120 grit wheel on the other. These all should be white, blue or pink AO wheels...NOT the typical grey wheels that you find in the hardware store. You need a friable wheel. You also need a diamond dressing tool to keep the wheels clean.
Harry Thornton
04-23-2005, 11:32 AM
Sorry, I should have said for turning chisels. I currently have the gray stone. I have heard those things are dangerous. I would hate to see it fly apart going that fast.
Jim Becker
04-23-2005, 12:25 PM
Harry, the problem with the grey wheels isn't danger...they are not any more likely to fall apart than an AO wheel. But those harder grey wheels tend to hold metal since they are not "friable"...particles don't break off while your are working. That gives them a glaze and makes for poor sharpening and increased heat. Change the wheels to the white, pink or blue Aluminum Oxide wheels and you'll be in good shape for sharpening turning tools. And consider investing in a Wolverine jig system for your grinder to help you have consistant results each time you sharpen. (Or build something similar if you need to...)