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For a look at another sharpener's solution to this problem, see
http://amktactical.com/epages/3c926a50-9aba-43a5-9571-098ee03f1288.sf/en_US/?ObjectPath=/Shops/3c926a50-9aba-43a5-9571-098ee03f1288/Products/24
Watch the video from about 1:30.

Thanks for that, Steve. Have you guys watched it?
Recently I got a few knives which to bevel properly I couldn't do without shims, so I watched that video, and applied their approach to SVM-45.
Shim is placed on the bottom jaw, i.e. between the static part of the clamp and the blade.
Maths for Tormek SVM-45 are as follows.

Spacing from the centreline of the handle to the bottom of the knife clamp (the static part of the clamp) is 1.5mm.
Ideal for 3mm blades, but well acceptable to 2.5-3.5mm thick as well.

For knives outside this range, shims can be used. I use blades from a Feeler Gauge with 1cm wide blades as shims.
Measure thickness of the knife at the clamping spot, and divide by 2 - you get spacing to the centreline of the knife.
Difference between 1.5mm and halved knife thickness is filled with a shim.

Example 1
Knife thickness 1.7mm, divided by 2 = 0.85mm.
1.5mm - 0.85mm = 0.65mm shim.

Obviously, for knives thicker than 3mm you should not put shims in the standard SVM-45 - for them I use a second jig with 1mm filed off the static clamp (described earlier in this topic).
Spacing from the centreline of the handle to the bottom of this jig is 2.5mm.

Example 2
Knife thickness 4.6mm, divided by 2 = 2.3mm.
2.5mm - 2.3mm = 0.2mm shim.

These calculations have been proved practically.

Hope this will be useful to you where a perfectly symmetrical bevel is required.

[SUN TIGER 800 grit compared to finely graded SG]

I got both SUN TIGER wheels for my Tormek-7: 800 grit out of necessity, and 4000 grit out of curiosity.
Now that I've had sharpened half a dozen knives on them, can share observations.

The SUN TIGER wheel diameter is 254mm.
The water trough fits almost flash, yet no brushing, no issues here.
I read Ken's concern that the wheel fits the bore very tightly, so as precaution before fitting the wheel I smeared the bore with a lanolin grease, but this was not needed with the wheels I got; I have no difficulty changing them.
The wheels had to be trued a little out of the box, but this is the case with standard wheels as well.
They soak up water slower, about 30 min.
I use KING Nagura stone for smoothing out after truing and for declogging the #4000 stone, and fine side of the Tormek grading stone for #800.

SUN TIGER 800 grit compared to finely graded SG
Note that Japanese grit JIS #800 corresponds to US ANSI #600, and European FEPA #1200, i.e. is somewhat finer than 'finely' graded Tormek #1000.
Sharpening on SUN TIGER wheel is a symphony.
No shortcomings of graded SG mentioned in the beginning of this post: hard grading can untrue the wheel and get the corners out of square, also, with use, the graded SG gets rough spots where the original grain somewhat opens.
2 thumbs up for SUN TIGER

SUN TIGER 4000 grit compared to SJ
Not that unequivocal.
SUN TIGER is definitely denser, it won't flake on the corners when trued or declogged (while truing SJ often leaves ragged edge), doesn't clog as fast, and won't wear off as quickly.
However, SJ is finer.
SJ leaves perfect mirror surface, and doesn't require deburring/honing afterwards. After SJ I can't feel a burr with the thick of the thumb.
SUN TIGER 4000 leaves a palpable burr that must be honed away, and the resultant bevel is not as shiny.
I'd say SUN TIGER grit is 1000 JIS less than SJ.
As a sidenote, they say SJ grit is 4000, but from my experience with bench stones I'd grade it at 5000.

Good job finding a solution.

Might I ask if you considered a piece of leather, like an old belt?  (tighten more at the high part and fatten out at the low)

A piece of leather or rubber should work probably, I'll give it a try with the next dagger.
But for this one I have to stick to shims as I also have to center the edge in the clamp, e.g. for this particular dagger I had to put a 0.5mm feeler on one side, and 0.4mm on another.

I sharpen daggers freehand, because they present a clamping problem with all guided sharpeners I know: Tormek, Lansky, DMT Aligner blade guide, and Razor-Edge guide. I don't have Wicked Edge, but their forum reads similar - the convex blade makes it difficult clamping a dagger.
Even when I thought I managed to fasten the blade in the jig, as I started sharpening, it crept out.

For a good minute I stared at the flat space by the ricasso... but dismissed the idea.   

Then I guessed that placing narrow shims on the sides of the dagger, narrower than the clamp depth, may extend contact area and improve the grip somehow...
Tormek knife jig depth is 12mm.
I used two 10mm wide feelers as shims.
And to my surprise it worked! The dagger sits in the jig like welded.

A few photos taken when bevelling the dagger.

Well..., huh.  I guess my exaggeration therapy was a failure, even though I gave it 110%. 

Mate, don't get me wrong, but there is no such thing as 110%

I understood butternut squash as a due sarcasm on obsession with super sharpness, bringing to mind other sharpness legends, like
-  katanas put upright in a stream should be able to cut cleanly through any leaf that floated down to touch the edge;
-  the knightly sword should be able to sever a human hair floating in the air;
etc

Wootz sayeth: "I do the full sequence for collector's pieces though".

I'll bet that if you exacting such care with your work,  the result is truly beautiful and impressive!

...yeah, and equally impractical.
One of many unnecessaries people do for "shear joy and understanding of achieving it"

Enjoyed your comment, thank you for good laugh

"...cell pokers for gene experimentation "  bugagaga

Can't argue that, it's definitely not for professional high volume work.
I do the full sequence for collector's knives though.

And sadly true that "repeatability before it dulls to just really sharp is so ephemeral" even with the high-end steels.

True if using Tormek honing compound.
Japanese Industrial Standards (JIS) 4000 grit is 3 micron particles, and Tormek Honing Compound consists of 1-3 micron particles, effective 3 micron.

However, extra sharpness can be achieved by honing with Chrome Oxide, which is 0.5 micron.
So, after SJ, I hone the blade on the Tormek honing wheel loaded with Green Rouge, and this invariably gives a sharper edge.
For harder steels, I also have to add a few puffs of 100,000# (0.25 micron) diamond spray over the honing wheel already covered with Chrome Oxide.

For example, I could never achieve hair splitting sharpness with SJ 4000 alone, shaving - easy, but as to the hanging hair test, the best I got was 'violin', but even that not always.
After honing with Chrome Oxide, hair splitting is a usual result.

In the "Experiments on Knife Sharpening" by John D. Verhoeven, in the chapter "Experiments with the Tormek machine", honing on the chrome oxide loaded leather wheel produces 0.35 microns edge as shown by scanning electron microscope.
The human hair cuticle is about the same thick, and a blade that sharp whittles a human hair lengthwise.

(Hanging hair test is detailed here http://straightrazorplace.com/srpwiki/index.php/Hanging_Hair_Test,_from_trick_to_probing_method#Controversy.3F)

Hi guys,

The Japanese Sun Tiger 800 grit grinding wheel has become available as of today from this German seller:
http://www.fine-tools.com/Tormek.html

Note that Japanese grit JIS #800 corresponds to US ANSI #600, and European FEPA #1200, i.e. is somewhat finer than 'finely' graded Tormek #1000.
The main advantage of using a dedicated 800 grit stone over graded Tormek standard SG is that you do not have to grade finer grit from the original 220 grit, and hard grading can untrue the wheel and get the corners out of square (the latter mostly frustrates knife sharpeners).

In 2009 Ionut had said all I could possibly say on this topic, so I just refer to his original post, a fragment of which I quote below:
http://forum.tormek.com/index.php?topic=897.0;nowap

"... the so called 1000 grit in my opinion is far from it. If you compare the scratch patterns between the Tormek wheel graded at 1000 and an actual 1000 stone there is a huge difference, and if you add a magnifier glass everything gets amplified. I've tried hardly to grade the stone to get closer results to the real 1000 I pressed the grader so hard I stalled the motor and the best thing I've done when pressing so hard and for long time was to untrue my wheel.
Using a 4000 Japanese stone the Tormek version SG250 for a secondary micro bevel improved a lot the amount of time the edge remained sharp, but I still was not where I wanted.
I got an aftermarket 800 Japanese stone and now I am tempted to change my occupation from "wooder" to "sharpener". All my bevels now are looking as they were before and the big difference is the edge stays as when I was using the manual version to sharpen my tools.

... with this settings all my search for getting always a perfect sharp edge VERY FAST, is over.
Ionut"

As Goethe said, theory is grey, my friend, but the tree of life is evergreen.

Hi Herman, what i was saying is that when I compensate for the bevel asymmetry by rotating the jig adjustable stop every time as the knife is flipped over, it is impossible to maintain exactly the same grinding angle, and therefore get a sharp edge, in a sharpening routine where passes are made alternating the blade sides.
And I alternate the blade sides with every pass in the last, finest, stages, on #4000 SJ and honing leather wheel, where 1 degree difference can dull the formed edge.

Searched all around, and looks like these guys are the only source of Tormek compatible #800 wheels:
http://www.fine-tools.com/Tormek.html
'New delivery expected February 2016'

The Japanese manufacturer itself offers a wide variety of grits, but the minimum order is 10 ea.

There is one practical thing I would like to mention. When we turn the adjustable stop one turn, we shorten the projection length by 2.5 mm (0.1"), which will cause an increase of the bevel angle by 1.5 degrees i.e. enlargement of the edge angle by 3 degrees. This may be a simple guidance for micro bevel sharpening.
Jan

A clever observation, Jan.
I've added it to my collection of Jan's adjustments.

This collection already has your sketch of the knife position in the jig, and this:
"One revolution of the micro-adjust wheel means elevation of the universal support by 1.5 mm (0.06"). This will increase the distance between the support and the stone, and cause that the chisel bevel angle will typically increase by 1 degree."

Much appreciated.

... I concluded that the knife jig is working fully symmetrically for knives which blades are not thicker than about 2 mm.

So, to modify the knife jig for 3 mm thick blades, for maintaining symmetry with respect to flipping, I would remove 0.5 mm from each clamp.

To modify the jig for 4 mm thick blades, I would remove 1 mm from each clamp.

Jan

Hi Jan. The source of asymmetry is that the knife jig has only one adjustable jaw, so the fixed is the one to work on.