I had the opportunity to hand-sharpen a half-inch twist drill bit
yesterday, when my too-fast drill press busted the tip of a cobalt 0.5"
bit while I was trying to drill a piece of 304 stainless steel sheet
0.060" thick.

I took Harold Vordos' suggestion if a while ago and sharpened an old HSS
bit freehand. It worked, and wasn't near as hard to do as it sounds.

I'm now trying to sharpen the split-point cobalt drill. It won't be
split-pint anymore, but that's OK.


At least one grindstone on the 6" Ryobi doesn't run true, wobbling from
side to side, making the world vibrate. What would be good replacement,
by make and model? Or, does one simply shim the wheel with cardboard?

Joe Gwinn