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Or ... use a calculator 

John, those drums are beautiful. You must be very proud.

Having said all this ... I am not sure if you ever file a warranty claim, they would have an easy way to know that you have used a wheel on an extension shaft.

All Tormek wheels are either exclusively for wet grinding (SB/SG/SJ), or wet grinding is very strongly advised (DC/DF/DE).

There is only a water trough on one side of the machine, so the other one would have to run dry with standard issue Tormek hardware.

Therefore I don't see how they would support using it in a way that would only help 3rd parties sell wheels.

I think if I ever need to sharpen a ceramic knife, I will stick with the DF wheel.

Ken, based on the findings of the scienceofsharp article, the finer the grit the better, so you should probably go for the DE wheel.

But from there I think it would best to move on to higher grits.  I wonder if the Japanese Wheel would improve the SG result?

My .02: you'll shape the wheel long before you notice any significant difference in the finish of the ceramic blade.

As explained in the scienceofsharp article, you need a hard support with fine particles to sub-microchip the edge in a consistent fashion.

Your edges look nice.

I was just commenting on this sentence :

Scratches in a ceramic knife apex work as crack initiators, and when those scratches get smaller and smaller due to progressively finer polishing the apex becomes more resistant to chipping as well as keener.

If anything having "smaller scratches" will increase the mechanical constraint due to local traction forces, so if this was the driving mechanism, the edge would be more prone to chipping.

But I think what's at play here is that higher RMS roughness along the edge results in areas where there is little material left at the apex, and these fragile areas will break off easily.

Back to the post of the OP, the SG is indeed much too coarse for it being any good on ceramic knives : it will tear off huge chips due not to the hardness of aluminium oxide, but to lateral stress on the blade at a scale corresponding to the rougness of the stone itself.

As a general comment, if you polish a scratch, you're essentially flattening the ridges, but the bottom of the scratch remains as it is. So there shouldn't be an impact on fissuration mechanisms.

That being said, I don't think these mesoscopic cavities are what drives the chippiness. As mentioned in the article :

the blade consistently separates along grain boundaries resulting in sub-micron roughness

.

The characteristic dimension of the grain boundaries is several orders of magnitude smaller than the typical dimension of your "scratches" (which aren't scratches as much as actual chips, really), so the local constraint is several orders of magnitude higher along those boundaries (as cavity size and constraint are inversely proportional).
 
It really is what happens on a sub-micron scale that matters for fracturation initiation, and it's not affected by polishing.

The thickness on the other hand plays a huge role in that it determines how far a fissure has to propagate before the material breaks.

[...] due to the much higher polishing process  i have found the resulting edges to be less chippy [...]

From a physical standpoint, "chippiness" will depend on intrinsic properties of the material used, and the thickness of said material.

So if the blade has a thinner apex, it will be more prone to chipping, not less. However, your particular sharpening process and methods may result in a geometry that will both be more resistant to chipping (so a thicker apex), but that might feel sharper as explained in the scienceofsharp article.

I believe this is an interesting read at
ScienceOfSharp.

It states that aluminum oxide abrasives are sufficient, however a much finer grit than the SG-250 is suggested.

Nice find, this site really is a trove of useful information. In a pinch, it says that you have to use reasonably hard, but very fine material so you chip on a sub-micron scale. Which requires a blade made of material that can separate on a sub micron scale. Using a glass substrate makes for a hard, smooth support that ensures that the "angle of attack" of the hard particles wrt the blade remains constant and controlled.

It also confirms that the initial "sharpening" of the blade with the sg was probably more of a roughing-up of the shoulders of the apex, resulting in two fine hacksaws.

And for those who can't/won't spend that much on BESS hardware, a simpler approach with a cheap microscope and nylon wire (fishing line) can be a good burr detector : mark a point along the edge with a sharpie, set the wire down on a board, align the wire and the sharpie mark, cut the wire using a downward-only (not rocking) movement, ideally not all the way through the wire, and check the spot under the microscope. A dent in the blade will be an excellent indicator of a burr remaining along the apex.

All for under 20 bucks. Easily made even better with a support that will hold the wire taunt an inch above the board while cutting, done in like 5 minutes with a chisel and a 2x2x2 wood block.

And for those who can't/won't spend that much on BESS hardware, a simpler approach with a cheap microscope and nylon wire (fishing line) can be a good burr detector : mark a point along the edge with a sharpie, set the wire down on a board, align the wire and the sharpie mark, cut the wire using a downward-only (not rocking) movement, ideally not all the way through the wire, and check the spot under the microscope. A dent in the blade will be an excellent indicator of a burr remaining along the apex.

All for under 20 bucks. Easily made even better with a support that will hold the wire taunt an inch above the board while cutting.

Once the burr was buffed off in the honing, the 180 paper wheel and the SB250  had larger "teeth" along the edge.

Just to make sure, you're talking SB250 for sharpening only knives, not SG-250 ?

The 'Free Grindstones for Life Certificate' guarantees you to exchange your grindstone if it wears down to a certain diameter. You can exchange your SG-250 Original Grindstone for Tormek T-8 if it wears down to a diameter of 7" / 180 mm, or your SG-200 Original Grindstone for Tormek T-4 if it wears down to a diameter of 6" / 150 mm. The exchange of worn-out grindstones will be administered by Tormek, and you will get at new Original Grindstone free of charge, shipping included. The 'Free Grindstones for Life Certificate' is valid for, at most, three (3) replacement stones in total within 25 years from date of purchase (based on the approximate service life of your Tormek machine).

I personally will not wait until my SG-250 is 7 inches in diameter before I change it. And at the current rate I am not even close to swapping it out.

I don't see any exclusions for professional sharpeners, but I guess they will reach the three grindstones limit way before their life expires after 25 years maximum Do any of you pros wear the wheel down to close to 7 inches before you discard it ?

Still it is a clever marketing stunt.

...
the KJ-123 is a giant step ahead of the Anglemaster for setting knife bevel angles.
...

Exactly.

Yup, and at a very good price point, I must say. Seeing how much they bill for a rubber mat, I was a bit worried to KS-123 would be in the USD 100+ range. Far from it

I do like to be able to set the angle to within about half a degree.  Why?  Because then I know exactly how to set my WS with blade grinder attachment to deburr the blade after sharpening, and at least as importantly, how to set it to strop the knife in between sharpenings. 

Given the precision of the WSKTS blade grinding attachement angle setting, I'm not sure one can get the .5° precision you mention. The slackness of the belt even on the tightest position is enough to change the angle by more than this. So if you set it to the same angle as the WS, you're probably at a higher angle where the belt meets the APEX. Which is fine for deburring and stropping.