02-01-2019, 01:09 PM
I went through a period of polished edges, but maintaining that level of sharpness was detrimental to the lifespan of some very expensive blades. Trying to keep your blade under 100 BESS just isn't practical.
I think it takes some refinement to get below 100 BESS, and once you're there it doesn't last long. The sharper you get, the more tenuous that edge becomes. It's normal to see something like 50 BESS turn into 75 BESS overnight... without any help whatsoever. Opening the daily mail can be disastrous. One UPS box later that fine pinnacle of sharpness won't want to cut a piece of string.
I've been measuring the knives I sharpen on 140 grit Atomas, and I know they should be about BESS 175-200, fresh off the diamond plate. There is a mighty big difference though. I can open mail for a couple weeks, boxes too, and guess what. Without any help at all, my blade can measure Sharper. It's like that coarse an edge takes some breaking in.
Mr Sharpco, when people say 4µ PDP leaves a "toothy" edge, you have to adjust your binoculars down to a completely different calibration. Yes, it's more aggressive than 4µ CBN, and CBN is more aggressive AO, but about the only way you're going to be able to make that sort of determination would involve shaving with a straight razor. The difference is noticeable- on your face.
On a typical stainless kitchen knife it makes a difference for about 10 cuts of 3/4" rope. Then it's really just a 4000 grit edge that went from 100 BESS to 175 BESS, and the microscopic teeth have already lost their crispness. A more tangible advantage of PDP is that it cuts steel much more efficiently- especially wear resistant steel. In other words, it's great on a hone because it doesn't take as many strokes to affect the edge. Less strokes means less chance for mis-strokes, and that is significant to me.
The kind of tooth Mr Grepper and I shoot for is much different than any compound is capable of. 150 grit tooth is... well, mathematically it's 27X coarser than 4µ (4,000 grit). It's like comparing marbles to basketballs.
Also, I agree with Mr Grepper that you are plenty capable of making your own determinations, and we will be more than happy to hear your conclusions.
I think it takes some refinement to get below 100 BESS, and once you're there it doesn't last long. The sharper you get, the more tenuous that edge becomes. It's normal to see something like 50 BESS turn into 75 BESS overnight... without any help whatsoever. Opening the daily mail can be disastrous. One UPS box later that fine pinnacle of sharpness won't want to cut a piece of string.
I've been measuring the knives I sharpen on 140 grit Atomas, and I know they should be about BESS 175-200, fresh off the diamond plate. There is a mighty big difference though. I can open mail for a couple weeks, boxes too, and guess what. Without any help at all, my blade can measure Sharper. It's like that coarse an edge takes some breaking in.
Mr Sharpco, when people say 4µ PDP leaves a "toothy" edge, you have to adjust your binoculars down to a completely different calibration. Yes, it's more aggressive than 4µ CBN, and CBN is more aggressive AO, but about the only way you're going to be able to make that sort of determination would involve shaving with a straight razor. The difference is noticeable- on your face.
On a typical stainless kitchen knife it makes a difference for about 10 cuts of 3/4" rope. Then it's really just a 4000 grit edge that went from 100 BESS to 175 BESS, and the microscopic teeth have already lost their crispness. A more tangible advantage of PDP is that it cuts steel much more efficiently- especially wear resistant steel. In other words, it's great on a hone because it doesn't take as many strokes to affect the edge. Less strokes means less chance for mis-strokes, and that is significant to me.
The kind of tooth Mr Grepper and I shoot for is much different than any compound is capable of. 150 grit tooth is... well, mathematically it's 27X coarser than 4µ (4,000 grit). It's like comparing marbles to basketballs.
Also, I agree with Mr Grepper that you are plenty capable of making your own determinations, and we will be more than happy to hear your conclusions.