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[it brings my stone out of square]

My interest in this topic is that I am also looking for a better alternative to the Tormek grader to create #1000 surface.
When used after the truing tool, it degrades the perfect squareness created by the TT-50, and because of that I haven't been able to produce a true and square #1000 stone. The resulting #1000 wheel is never as right as immediately after the truing tool.

It's exactly the same problem Ionut described in the link above - a quote:
"I don't like to use the grading stone, it is for grading and not dressing, mine already has no more flat surfaces left that I can use and I don't use to grade my stone anymore, it brings my stone out of square and I already have a 1000 stone."

Unlike Ionut, I have no idea where from to source the #1000 stone and have to grade it from the SG-250, and this causes lots of frustration.

Diamond lapping plates should work, but DMT doesn't offer the grit I need, and again I'd rather buy a dedicated #1000 wheel than diamond graders to make it of #220 SG-250.

I realized the problem with adjustments every time as the knife is flipped over, is that when I have to alternate sides, it is impossible to maintain strictly the same angle, and because of that I cannot get sharp edge.

I ended up by buying a second knife jig, and filing away 1 mm from the static clamp.
Now I have a dedicated jig for knives 3mm and over thick.
Not that I recommend this to everyone, but if you sharpen many thick knives, this helps to minimize the bevel asymmetry.

[For those of us who are old enough to be able to learn from reading...]

For those of us who are old enough to be able to learn from reading...

Ken, you can be so hilarious!

Search brings up a few past posts of people's experience with DMT plates for dressing, the most interesting is Ionut's:
http://forum.tormek.com/index.php?topic=1078.msg2720#msg2720

Wootz, you say "Notice the chipped edge".
Does that mean the DMT caused it, or you were using it to work it out, or it is the reference point for your wheel?

The DMT plate caused it. And when I was experimenting with a Spyderco ultra fine ceramic benchstone, it also resulted in a ragged edge, which together draw us to the conclusion that the gentle Japanese wheel does not like hard dressers.
The softer Tormek fine grader and Nagura don't cause this sort of damage.
Notice concave wear in the Nagura in the photo.

I happen to have an SJ-250, the Japanese grinding wheel. I will be curious to see how the 8000 grit diamond stone dresses the SG-250 in comparison to the Japanese wheel.

Hi Ken, I happened to have Extra Fine DMT, which is 1200 mesh, ~ 2000 JIS, and tried it on the Japanese SJ-250.
Below picture is after 30 sec to 1 min of dressing with the DMT plate. Notice the chipped edge.



As I wrote somewhere else, when I got SJ-250 I tried whetstones and ceramic benchstone on it for dressing, and finally found Nagura intended for #4000+ the best. Nagura leaves definitely better surface on SJ than the Tormek grading stone, with less waste.
The following photo is after  1 min of dressing with Nagura.

I bought a few from this mate on ebay http://www.ebay.com/itm/Japanese-whetstone-KING-Nagura-sharpening-waterstone-sharpener-tool-knife-water-/391139052736?hash=item5b11b44cc0:m:mL7D0J2mJ70P7j1WX4Ctu4w



This does not, of course, deny usefulness of DMT for dressing a regular SG stone, as per Andy.
Generally speaking, looking for better implements is inspiring, and, ultimately, rewarding.

[sleepydad]

sleepydad,
Wouldn't grading a stone put a lot of wear on the diamond plate?
I've always thought it's the shortest way to ending life of your diamond plate.

Shapton produces a lapping plate for stones by fusing diamonds in the glass,
and DMT produces Dia-Flat Lapping Plate by special technology for flattening water stones,
but regular diamond plates are not designed to withstand the extreme conditions incurred when flattening other abrasives.

A quote from the DMT website:
"Some DMT Diamond Sharpeners could be used (and have been used) for flattening, however, they were designed for sharpening, not flattening, therefore, DMT assumes no liability for sharpening stones worn out due to this method of use."

Personally, once I tried flattening an Arkansas benchstone with an EZE-LAP diamond plate, which stripped off a good deal of the diamond coating.

And Ken was through something similar: "I recently almost ruined a two hundred dollar  diamond flat plate truing my grandfather's carborundum bench stone. That was really dumb." http://forum.tormek.com/index.php?topic=2337.msg11363#msg11363

Your DMT plates, do they show much wear from grading the Tormek stone 'for years'?

You're damn right, Elden!
Following you remark, I tried editing my post to make this clear, but probably it reads even more confusing now. 
Honing must always be carried out away from the edge.

And don't assume that the stone wheel out of the box is true - it is not. And it is next to impossible to get a shaving edge on a wheel that is out of true. I've unpacked the 3rd stone by now, none of them was true nor perfectly round out of the box.

My first knives on Tormek were as disappointing as yours.
I remember doing these simple things gave me the first shaving edge:

• Use regular knife jig (forget the long jig for now).
• True the stone.
  Don't grade it yet - grind the bevel at the set angle on the freshly trued surface.
  
• Then grade the stone fine (#1000), and grade hard.
• Do as many passes as needed to get burr on one side.
• Inspect the edge, and continue on the same side till you smooth away all scratches left by course beveling, and get even finish along the whole length of the edge.
• Then flip over, and get the burr on the other, and get even finish.
• Flip over to the initial side, and do one more light pass.
• Remove the jig, and hone freehand as  Jeff Farris taught:

Hold the side of the blade, edge up, at 3 o'clock on the honing wheel (instead of 12), about half an inch from the edge. Stand just above and stare straight down into the gap between the edge and the leather wheel. Bring the edge to the leather slowly until the exact point where the gap disappears, until the edge just barely touches the leather. STOP!
Make slow pass across the wheel.
Turn around to hone another side of the blade (now at 9-10 o'clock), and do the same.
Overall do 4 alternating passes across the leather wheel.

At this point the blade will shave your forearm.

Knives should be mounted in the jig as shown by Jan. This helps avoid jig position effect on the bevel described in the Tormek Handbook p.53.

[Edge rounded by honing]

As to honing, let me quote Jeff Farris:

Edge rounded by honing
This one happens seldom enough to almost qualify as an urban myth.  There's a lot more theoretical rounding over going on in various bulletin boards than real life rounding over happening on TORMEK machines.  You have to bring the angle way, way too high to actually start rounding over an edge.  That said, when you begin using the system, it may not be that easy to tell where you are on the wheel with relation to the edge. One way to solve the rounding issue is to use the jig when honing the bevel.  With the jig, you can apply much more pressure to the honing wheel, thus speeding up the job and preventing round over.
... work at 3 o'clock on the honing wheel, instead of 11 or 12. Now, you can look straight down at the gap between the edge of the tool and the leather.  Start out with your angle too low, and then slowly bring the angle up until the edge just barely touches the leather.  Now, you'll polish the surface and remove the burr without creating a back bevel or rounding the edge.

[Long Knife Jig asymmetry problem]

Hi
Another question.

It seems that the bevel on one side of the knife is different than the other side.
I do the first side then flip the knife and do the other side.
One is wider than the other?
Just wondering if this could be part of the problem?

Uneven bevels result from the design of the knife jigs, and is more noticeable with the long knife jig. The thicker the knife, the more the difference.
It was discussed in the Long Knife Jig asymmetry problem topic http://forum.tormek.com/index.php?topic=2577.0

Thanks for sharing your experience - next time will be long soaking the SJ before truing.
And my two cents. For declogging and cleaning the surface between sharpenings, I started using Nagura intended for #4000+, and find it as effective but more gentle than the standard grading stone; also after Nagura the surface grit definitely feels finer.

I see the same with my SJ, and mine was trued after 1-2 hours of wet use. I've trued it 3 times by now.
And it is not only truing with TT-50 - unclogging with the fine side of the grading stone leaves a ragged edge on the wheel as well.
Had another look after reading your post, and true, the inner edge got dented more than the outer, but the outer was not spared either.

I tried using a finer 5000 grit Japanese whetstone to grade the wheel, all the same - I mean smooths the stone surface, but detrimental for the edges.
I also tried unclogging/grading with a hard ceramic 2000 grit stone - definitely more damaging.
After all experimenting, I stick to the fine side of the Tormek grading stone, but I haven't tried Nagura yet.

What is your impression of Nagura Stone use on the SJ for declogging/grading? Are you using a Nagura made for finer grits?

(I can't agree with jeffs55.
The Japanese SJ-250 delivers more than the honing wheel, and for high end knives I cannot skip it.)

Referring to your image below, I would like to ask you, how do you use the laser LOC to sharpen the tip without pivoting the knife?

Hi Jan, just by eyeballing along the LOC and further to the staight part of the blade, kept them in line.

Have you measured the degrees of the bevel angle along the entire length of the blade after sharpening?

Edge angle in the above 3 knives sharpened without pivoting is about the same +/- 2 degrees along the straight part and into the belly, then increasing by 6-13 degrees near the tip (included angle).
So, set at the heel to the included angle of 30 degrees, and sharpened without pivoting, it resulted in 34-42 degrees near the tip.

Bevel face width practically doesn't change from heel to the tip, while the bevel base thickness does increase at the tip.