Sharpening on a grinder?

Daniel Macina

Well-Known Member
ok so I've always sharpened knives using stones but I've never had great stones or great technique and now that I have a grinder I figured I would start sharpening on that. Would you mind walking me through the grits, compounds, and your overall sharpening process?
 
Finished edge geometry dictates everything. If you leave ANY other then the tinest "flat" on the edge, you'll have to start with a 220 or 320. I strive to have all my edges "ragged sharp" when I complete finish grinding, so I sharpen carbon steels with a worn 400 grit belt. If the knife is a "user" it usually gets left like that, if it's going to a collector, or someone who want to impress their friends, I give each side a light pass on a loose buff with Pink no-scratch compound, so whomever can shave their arms for their friends! :)
I don't use "angles" on my edges, but rather convex edges, to that end I sharpen in the slack belt area between the top wheel of a flat platen, and the idler/tracking wheel..... running the machine at 20-30% on the VFD...... If I nail the finish grinding, it usually only take a single pass on each side of the blade, with just the weight of the knife.

It's a totally different story with Stainless steels. Depending on the given stainless, and the heat treat, it's often a requirement to have a some level of a "flat" on the edge. 220 is where I start, but then have to run the entire grits of belts all the way to 1200 to do any good. When buffing off the edge on stainless blades, the loose buff with pink no-scratch won't do...... I use a sewn buff with Matchless green.
 
Back
Top