Ken, this is beautiful! I didn’t know that some natural stones leave such a finish. Is that because the abrasive stuff in the natural stones is softer than in most synthetic stones? It gives a beautiful finish. (And now I know it, I suddenly see this finish on many other Japanese knives.)
But what is absolutely amazing are your sharpening skills.
:woohoo: :woohoo: :woohoo: :woohoo:
And then: three degrees! And then just go to five degrees and know that it is five as if you do nothing else all day :woohoo: .
And then such a beautiful beautiful knife :cheer:.
I am going to drop dead in just a minute… :silly:
“I didn’t know that some natural stones leave such a finish. Is that because the abrasive stuff in the natural stones is softer than in most synthetic stones? It gives a beautiful finish. (And now I know it, I suddenly see this finish on many other Japanese knives.)”
Your reasoning is exactly correct. Aluminum oxide and silicon carbide, two of the more common abrasives in synthetic stones are FAR harder than the natural abrasives found in Japanese Natural stones so there is very little differentiation between how they react or treat the softer and harder steels. The natural abrasives are both softer and more varied in particle size distribution and individual particle makeup. The shapes of the individual particles themselves are not the precise spheres and other regular geometric shapes we see in synthetics and compounds, but sometimes are more flakelike or have other shapes that are more mine specific. The binding mechanism is different too than the binding sysytems employed in synthetic stones.
Mark, my sharpening skills are not as amazing as you are saying at all. Let me clarify. When I got this knife used some time ago I resharpened it using a device I made for controlling angles and at that time I made a symmetric triple bevel with the device at 3.0 degrees, followed by a microbevel at 5.0 degrees followed by a third bevel at 7.0 degrees – three distinct bevels, per side with all three bevels per side (six total ALL polished up to a fine grit level (I believe it was a 16k Shapton GlassStone finish if I correctly remember it.). I did this as a technique demonstration at the time because I knew of no other device capable of doing this (still don’t).
I could not do this freehand and don’t think anyone else can do it either because doing it (especially for 311 mm at the same three angles) is, IMHO beyond the mechanical abilities of the human hand to do freehand at this level of precision.
What I am doing in this video is much more humble a goal. I am blending these three distinct angles into a convex bevel – much like smoothing out the corners of a stop sign into a circle. This convex grind is often referred to as a hamaguri grind. This is within the limits of human precision. I am also doing more of a zero grind – in other words there is NO bevel on the edge at all – just the two sides of the knife meeting. This is accomplished by pressing very close to the edge of the edge. So this edge is somewhere between a zero grind and a very acute thinned hamaguri grind.
Here this stone is somewhat softer than a Shapton and the mud acts to give a less precise grind, allowing the rounding or convexing to occur – favoring the conversion to a hamaguri grind.
What is most interesting about this particular stone is the way it differentiates the soft cladding from the harder core steel and gives as close to a natural stone finish as any synthetic stone I have seen. Furthermore, even among natural stones, the kasumi finish or hazy finish is often less consistent than this stone. When I shot the video and first turned the edge over to see what I had done, I was about to squeal some ‘expletives of joy’ but fortunately caught myself from ruining the video. That a synthetic stone is capable of doing this is most remarkable and reflects a very deep understanding to have even created such a stone. Seeing this stone in action gives me a great deal of humility to stand before it seeing this being accomplished – far beyond my level of understanding as to how this stone was formulated.
So going back to the original topic, bringing out this level of contrast on a knife like Murray’s would be a particularly nice way to enhance or more accurately bring out the quality of his work using a natural stone finish. His steels are very traditional Japanese steels so doing this would be a very nice matchup.
Doing this on the Wicked Edge would allow producing this effect to be done with precision. I have natural stones mounted on the WE platform specifically for this task – going from coarser natural stones like the Amakusa and natural Kyushu Ohmura to natural Aoto, Binsui, Igarashi and Yaginoshima Asagi to name a few. I had planned to introduce these a bit later to the Wicked Edge, but given an interest, I can certainly move this along more quickly.
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Ken
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