Questions for Cliff Stamp

Mr. Stamp
It's me again asking you about sharpening. I took your advise and got a big Japanese Water Stone from the Japan Woodworker. I think I may have made a mistake in grit size. As I understood the grit size scale... 600 or 700 grit is very fine and 100 grit is coarse. So I bought a japanese water stone whose lowest grit was 700. That was the lowest they went. Later i come to find out it made reference to the 700 grit being the coarse and the 3 and 6 thousand grit hones being the fine. Do Japanese water stones go by a different grit rating system than regular stones. because I always assumed that 700 grit wan a nice grit to finish your edge upon. And this thing is as rougher than any of my other fine hones like the sharpmaker white rod. I'd appreciate it if you could break this down for me as I hope to be the best sharpener possible for all of my Busse knives as I expect the best from them.

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First impressions are usually the scale by which we are judged unless we make our second with something sharp and pointy.
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[Paracelsus]

Ryu, YES, the grit rating system used for Japanese water stones is different from norton bench stones and sandpapers. A 700 grit stone would be used for heavy metal removal. A common multipurpose stone to use is a1000/4000 combination. A 4000 grit stone will produce a very fine edge. Finer grits may or may not produce a noticeable difference (depends on the steel and the edge geometry). I personally don't use my water stones much anymore, preferring the low maintenance, no mess convenience of ceramic stones (medium to extra fine). The grit rating system for diamond stones is also a little different. There is a Norton chart that compares these numbering systems, but I have my doubts about the chart. It claims a fine diamond stone (1200) is the equivalent of a 6000 water stone, and that is bunk, IMO. It is more like a 2000-4000 water stone. Feeling the stone with your finger is usually the best way to see how fine it really is. Best of luck!

Paracelsus

 

[Paracelsus]

This is the chart I mentioned. As I said before, I do not think it is entirely accurate. But it does a good job of demonstrating the difference in the numbering systems between different types of abrasive materials.

Ideally, they would all be the same, standardized by their average particle (cutting units). But they are not. In each type of stone, there is an average size 'particle'. This will change during use. The reason waterstones work so well is that new material is constantly exposed, producing a more consistant cutting action. Diamonds and ceramics both wear (particle size breaks down), but very very slowly.

You just have to get used to what is coarse, medium, fine, very fine, and ultrafine in each type of stone. Fine diamond stones and medium ceramics cut at about the same rate. I think the very fine white ceramics leave the best edge. But I almost always strop to finish the edge. This may not be the best kind of edge for you needs.

 

Thank you. do you know where a guy can find a good set of ceramic block sharpeners. I have the spyderco sticks but was looking for a block about 8" X 3" X 1" that have stones at 100 grit, 250 grit, 400 grit, 500 grit, 650 grit and finally 800 grit to finish on.

 

[Cliff Stamp]

As Paracelsus noted, there is not a widely used standard in regards to hones. You can get fine in one behaving like coarse in another.

That chart seems really off to me in terms of cutting ability, do you have any information as to how this was determined? If I had to guess I would say that very little force was applied, which is not the case when using them on blades (with the exception of Diamond hones).

Spyderco I think sells ceramic benchstones.

-Cliff