[jimmontg]

Dave I chopped through a bunch of dymondwood first thing. It didn't affect the edge that I could see. Then I commenced to slice cardboard. Lots of it until the edge got dulled and it took a lot Dave. I would guess about 20 feet of cardboard if not a more. Cardboard is abrasive as it picks up dust and I was using recycled. I initially sharpened the blade with 220. After establishing the edge I wanted, I used a medium grit EZE Lap diamond sharpener that is over 15 years old so it is between medium and fine. Once all the edge was even I finished it with a hard and fine Arkansas stone. It would pop the hair off your arm.

Because of the way I sharpen I do not leave a burr on the edge. I always slice into the stone and never slide backwards, backwards leaves a burr. I sharpen by hand, always have, it is how I learned. I also hold the stone in my left hand and twirl it as I sharpen, it is why I never round off the point on a knife. Also why I never sharpen after a couple of beers. I've cut myself doing it that way, but again it is how I learned.

I really don't have a problem with carbon or stainless. It does depend on the edge geometry, but the only real hassle I've had sharpening a stainless knife is one with Chromium or Vanadium in its alloy as it really makes it tough to sharpen. Vanadium carbides like in the S35VN Dave make a knife abrasion resistant and therefore hard to sharpen. Hard 440C, I mean like at HRC 59-60 also create chromium carbides and they are harder than iron carbide and that is why a carbon steel knife tends to be easier to sharpen. I use a diamond, it is the only sharpener to use by hand as trying to sharpen good stainless knives with Arkansas, Crystolon or India stones just takes too long or even Chinese polishing stones.

I will start with a fresh, this is important, 220 silicon carbide or coated pre-lubed ceramic belt and establish the edge. A slightly worn belt and you could easily turn just barely a small part of the edge blue and then you have softened it. Remember that the stainless, if HT properly and especially if it has had a cryo in liquid nitrogen will have very tough abrasion resistant carbide and it is very easy to anneal the edge, I know from experience, I will not use anything but a new belt and I will not use cheap AO belts. The silicon carbide belts are best because I can keep them damp and therefore cool. You don't have to spray water all over, just keep it damp with a wet rag.

I have a S30V filet knife I can put a shaving edge on, though I won't as that is too sharp for filleting fish. I put a working edge or what some call a butcher's edge, about 800 grit. I suspect that a lot of stainless knives not getting sharp from sanding belts may have a lot to do with the chromium and vanadium carbide's hardness and if you throw some niobium into the mix like with S35VN it would be just a bit harder. You also have to take into account that some custom knives are HRC 61-62 hard and even some Scandi knives made from high carbon like 1.75% come in at HRC 63-64 and that is harder than most files. The finer grits do wear out fast if not coated. I have noticed this with the 15 micron belts, they must be coated and as I say below I use Tap Magic, a thin cutting fluid.

I can only tell anyone who is using belts to get a final edge to be sure and use new sharp coated belts and do not use cheap AO belts. Those 1200 grit or 15 micron belts don't last very long. I use a rag and put Tap Magic cutting oil on them to keep them clean. I put it on a rag and apply it very thinly and often. I would also strop it by hand on leather glued to a stick. If I want a razor's edge I strop on leather glued to a stick about 10" long, I do not use polishing compound I use 10,000 grit diamond paste. I use diamond paste in different grits for polishing as it works very fast.

As for a convex edge having a hard time slicing paper I am referring to a steep edge geometry not a thin convex edge. No point in putting a thin convex edge over a flat edge if the steel is chippy it will be chippy with both. I would use CPM 3V if going with a thin edge or a good carbon steel like 1080V or O1 with Vanadium, it usually has .2% and all that does is make a finer grain. O1 is my personal favorite for a carbon steel alloy. Not all O1 has the V so check.

How to tell the knife is sharp after the 220 grit grind? Look down onto the edge, edge up and if you cannot see any shiny spots on the edge the knife is ready for the next size or in my case its ready to finish by hand. Just in case there is a newbie reading this.