How sharp can a 20 dps blade get?
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Glenn, first 170-180 BESS score is respectfully sharp and nothing to sneeze at.
Without knowing anything other then 20dps setting and your grit medium progressions all I can suggest, (and assuming your diamonds are well broken in), is to recommend more effort and attention to detail. Simply put, make sure your angles are checked for preciseness, adjusted and locked in with each and every grit change. Spend more time and effort then you have with each grit in your succession. When you think you’ve done enough and time to move onto the next grit, do more strokes.
Inspect your scratch patterns with a magnified visual aid to be sure your scratches are evenly spaced, even depth and all running in the same direction, nice pretty and parallel. Use alternating side, L-R-L-R, edge leading, down and onto the edge, strokes as your last sharpening strokes with each and every sharpening grit.
Repeat this added attention to detail and effort over and over again as you work through the progression. Follow the same progression you had before, just spending more time, effort, and care with each grit.
Testing again will show you your results. Plain and simply if your results improve the extra effort and attention to details was what you needed to be doing. If you see no improvement then it means you’ve been doing a good job and your results were what you’ll get. The best you can do with what your working with.
Marc
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Thanks for the tips. I always finalized each grit with edge trailing strokes, maybe that will help.
And I agree a BESS of 180 is not dull. I’m just mostly geeking out on sharpening.
Also, thanks for all of your knowledgeable input in this community. It has been a great help to me.
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I finish each grit with using the edge leading strokes. This makes sure I have removed any remnants of a burr and exposed the sharpened edge.
Marc
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There are two points I’d like to emphasize, and Marc alluded to both:
“When you think you’ve done enough and time to move onto the next grit, do more strokes”
At a microscopic level, each grit must eliminate all evidence of the previous grit. You can generally see the scratches left on the bevels, but you probably don’t see fractures left at the apex by the same grits that made those bevel scratches. Pieces of the steel at the apex are broken free, leaving damage that extends far deeper than the normal scratches. You should endeavor to repair that damage before moving onto the next grit and the way to do this is to simply add more strokes at the exact preset angle. Having done so, consider that now you’ve left apex damage caused by the current grit and you’ll need to remove it at the next grit in the progression.
The second point is the direction of your strokes. Edge-trailing strokes tend to create more fractures at the apex than edge-leading strokes and therefor ought to require less strokes at each step. This is probably less of a factor with the higher grits, but I haven’t seen actual evidence to support my theory.
The sharpest knife I’ve ever used was a Japanese Santoku my sister bought for me at their shop in Kyoto. They sharpened it while she waited and when I received it, I found the edge to be at 6 dps, with a plethora of what we would call edge defects. At such a low angle, the edge was “foil-like.” If I pressed my thumbnail against it, you could see the steel bending. The edge was rough as hell, but it cut like no knife I had ever held.
All this having been said, it’s my opinion that nothing improves perceived sharpness like reducing the angles, but I sharpen most of my knives at 20 dps, as I’ve noticed a reduction in edge retention as you go below that number, at least in the several knives I use daily – EDC’s and kitchen duty.
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I get the obsession but if you achieve this ultimate sharpness, how may cuts will it last? What are you cutting, BESS test paper or rope, or card board boxes.. or wood or what is the knife used for and will it actually work better or worse with the ultimate sooth edge? I may not be enough of a knife geek.. I just want the thing to cut what I am cutting.. 🙂
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Here is some great stuff to read while killing time, easy to find on the net, some of it is in the WEPS Knowledge Base, I think
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One bit of advice I can offer is to lighten your pressure considerably with your final strokes. Another thing we learned in playing around with the Bess machine is that the Micro-Fine ceramic stones took us below 100 very quickly.
-Clay
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One bit of advice I can offer is to lighten your pressure considerably with your final strokes. Another thing we learned in playing around with the Bess machine is that the Micro-Fine ceramic stones took us below 100 very quickly.
So, the guy that sell the stones…is recommending more stones…
Just kidding
I just ordered some Micro-Fine ceramic stones.
Thanks for the tips.
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Those micro fine ceramic stones are really good. The 0.6 micron is my preferred finishing stone these days.
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I just ordered some Micro-Fine ceramic stones. Thanks for the tips.
Glenn, just so you know, the ceramic stones are used just like the diamond stones, except they have a long break-in period. They seem to have a coating on the stones from the high heat manufacturing process. They do require some amount of use and wear to remove this coating and to get the best results out of them. They are non-magnetic and they can be brittle. So handle them with some care because the ceramics can break if dropped.
Marc
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