The quote about the F and UF Spyderco stones comes from Cliff Stamp on his blog:

When I first used the micro fine ceramics (esp. the "brown" stone) , I did notice a different scratch pattern on the edge, however, after lapping them, the scratch patterns appear to be much more refined and consistant although I am not looking at them under 200x. Just my 2 cents but I'm curious to see other results.

wickededge wrote:



Here's a bit more info you might find interesting from Sal (Spyderco's president):

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All of the ceramics use the same micron size (15-25). the different grits are created by different carriers, different firing techniques and diamond surface grinding.

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We've spent a great deal of time trying to determine grits for our stones. The manufacturer has also worked with us, to no avail. A guess seems to be best.

Most abrasives are measured by the grit size used in the matrix. Our ceramic doesn 't work that way. Grit size is constant.

We've tried to compare scratch patterns as Cliff mentioned and this is probably the closest, but nothing that we can say "This is blah blah". Then the Japanese water stones jump into the equation and suddenly there is whole new set of numbers.

So where we end up is:

Our diamonds are a 400 mesh (measureable). (600 on the Duckfoot)

Our gray stone is "medium". (Same material as fine but different carriers and heat treat).

Our fine stone is fine.

Our extra fine is a surface ground fine.

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Our Ultra fine stone took many years to develop and few know about them. I was convinced enough with the stone's potential that we finally were able to make a 3" X 8" version that is not much more than a quarter inch thck. Two sides, flat and fine.

It took five years for our R&D teram to finally produce this stone. The challenges kept cropping up and needed to be overcome. Technology in the area of ceramic stones has improved and we can now make stone shapes before not possile.

We have the new UF 3X8, a 2" X 4" fine slipstone with 1/2" down to 1/8". And we also have a ceramic version of the byrd duckfoot, fine grit. A true "Golden stone". The downside is the high cost.

50,000 years from now when the Pyramids have crumbled and humans are but a memory, Spyderco ceramic stones will be seen sticking out of the earth, ready to work.

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Source: www.spyderco.com/forums/showthread.php?3...ed-to-DMT-extra-fine

Thanks for posting CBW, that's awesome info.

With all of this info on the Spyderco stones, I wonder whether the Micro Fine ceramics are the same material as the Spyderco fine/ultra fine stones? Or are they different stones that happen to be made by the same manufacturer?

I don't have the Spyderco stones for comparison and the manufacturer doesn't kiss and tell It's a good question though and maybe I'll order up a set so I can compare.

mark76 wrote:

My perception is they are not the same. The Spyderco stones feel a bit harder and just feel different. I have all the Spyderco bench and Sharpmaker stones as well as a 701 profile set. They are all the same as each other (by grit) and different from the WEPS ceramics. JMO

Ken

I happen to have a Spyderco Sharpmaker, my favourite sharpening system until I got the Wicked Edge. My Sharpmaker came with two stones, which Spyderco calls "medium" and "fine". As cbwx34 wrote, Spyderco hasn't published any grit/ratings or micron sizes of these stones.

Here are the Spyderco stones next to the Micro Fine ceramics.



As you can see, the color of the coarse micro fine ceramics is exactly the same as that of the Spyderco medium stones and the color of the fine micro fine ceramics is the same as that of the Spyderco fine stones. Coorstek has probably used the same pigments to color the Spyderco stones as the Wicked Edge stones. To me the stones also feel very similar (smoothness, hardness).

I took a few pictures of each of these stones under my microscope. This is the Spyderco medium stone:



And this is the coarse Micro Fine ceramic:



Although they look similar, the difference between these pictures seems significant: also if I take pictures on different spots on the stones, the Micro Fine ceramics have more and larger grey areas.

This is the Spyderco fine stone:



And this is the fine Micro Fine ceramic:



Again, the difference between the pictures seems significant: the Spyderco stones have more white spots, all over the stones.

I don't know what to conclude from these pictures, other than that both the Spyderco and the Wicked Edge stones have similar structures, probably because they have been manufactured using similar processes. Which is not too surprising, since they were both manufactured by the same manufacturer .

But it would be interesting if somebody could take a microscope picture of the Spyderco ultra fine ceramics.

To show that not all ceramic stones have the same structure, here are microscope pictures of the 1200/1600 ceramic stones. These were made by a different manufacturer.

The 1200 stone:



The 1600 stone:

mark76 wrote:


I agree... they seem more similar than different. I guess you could do a comparison picture of what type of finish they leave on a knife... although the fact that the stones' finish can be altered by lapping, this probably isn't necessary... or wouldn't really tell that much anyway.

Nice pics!!

I have experimented a bit more with these stones and I took some additional microscope pictures. I think these stones are a bit coarser than I initially thought. See my blog update.