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I happened to have micrographs of the Tormek honing compound and Autosol metal polish in the same scale.
Now we can compare their grain size.

Tormek honing compound PA-70 (microscopy by Anthony, USA):


Autosol metal polish (microscopy by Iliya, Australia):


To my eye, the particles in both are of similar size, in the range of 3 to 10 microns (not taking into account the conglomerates).
What do you see?

They have similar honing ability, but in my experience the Tormek PA-70 does better at slow RPM, while the Autosol at high RPM.

Next image shows a mainstream kitchen knife sharpened on a coarse wheel of #200-300 and then deburred (polished) on the Tormek leather wheel.
Very good result telling us that we can do the majority of mainstream knives and common woodworking tools without a fine grinding wheel. A coarse and medium wheels can do the job, thanks to the honing compound working so good.



What the 2nd image also shows us is the wire edge or feather burr seen all along the apex after the honing.



We see this picture all the time, off the Tormek leather wheel, and off the paper wheels - and it tells us that the root of the burr is still there.
That is the reason we do one more step of deburring that we call "de-rooting" the burr, or "de-wiring", to get a strong clean apex.

https://bladeforums.com/threads/wheel-grind-a-straight-edge-without-overgrinding.1733595/

You've heard that CBN and diamond wheels grind better than stone wheels, but that is given the pressure on the blade is the same.  Since pressure on CBN and diamond wheels is to be less than on the stone wheel, to see their grinding advantage we need higher RPM.

Generally speaking, with the evolution from stone toCBN and diamond wheels that dissipate heat from grinding very well, the Tormek RPM could be increased to 250 RPM. You will not want that much speed in precision grinding of delicate blades, but for grinding bevels on grossly dull knives and tools or reprofiling you'd love it. So if this ever is going to happen, it better be done with a removable RPM-increasing insert that the user can put on the motor spindle when he needs more intensive grinding.

[explanation given by Ton Nillesen in 2018]

NEED FOR UPGRADE
In its current form, our software sets an accurate grinding angle for resharpening a knife with established bevels at the existing edge angle.
E.g. you resharpen a 15 degrees per side (dps) knife to the same 15 dps.

However, when grinding new bevels, sharpening a grossly dull knife or a knife blank gives an edge angle differing from the calculated target by 0.5-1.5 degree. The thicker is the blade behind the edge, and the lower is the new edge angle, the greater is the difference.

To complicate it further, when sharpening on a coarse wheel, you may get a higher than the calculated angle simply because the jig projection shortens as you grind off the apex and raise the burr.

For example, when you resharpen a thin kitchen knife on a fine wheel to the same edge angle as this knife already has, you get the edge angle within 0.1 degree of the angle calculated by our software. But when you sharpen a thick hunting knife on a coarse wheel, you get an edge angle by 0.5 degree higher if sharpened at the original edge angle, and by up to 1.5 degree higher if reprofiled to a lower angle.

If you have a laser protractor, observing how the edge angle changes in the process of shaping bevels gives a better understanding of what I am writing here.

NEW INTERFACE
The new interface has additional parameters in its "Blade" section, to address the above and improve accuracy.



STATUS
I've coded the computer algorithm and currently testing in sharpening blades of varying thickness.
The calculations are along the lines of the explanation given by Ton Nillesen in 2018 on the page 6 of his additional booklet that can be downloaded from our website http://knifegrinders.com.au/Manuals/Grinding_Angle_Adjustment_Booklet_2018.pdf

The blade position on the grinding wheel changes as the sharpening progresses, gradually lowering as the edge apex travels the distance of the blade thickness behind the edge, as shown on the following schema:


This downwards shift of the blade and the knife jig it is clamped in increases in the duller edge, the thicker blade, the coarser grinding wheel, and the lower grinding angle. If not corrected, the actual grinding angle will be differing from the target.

As I am happy with my testing, we will prepare an upgrade, first of the computer-based applications, Windows PC and MacBook, and email an upgraded download to our over 1000 customers.

I am not as sure about the mobile applets, though. iPad and tablets are no problem and we will sure upgrade them and find a way to deliver to our existing customers, but the phone screen may be too small to accommodate the additional settings.

We will also upgrade our Frontal Vertical Base software with these advanced settings. But again, the phone applets are a problem, as they hardly take even the current FVB interface.

As we all understand, this is not only about the edge angle accuracy, but for better matching the grinding and honing angle to get a sharper edge.

We will also have to update the applet manuals and our webpage with the new information.
Overall, we need about 1 month to complete this upgrade, and appreciate your patience.

Cheers, Vadim

Michael from Denmark, a professional sharpener, employing our software for Tormek in his business, has shared his sharpness BESS scores.
His sharpening equipment includes 2 Tormeks with all grinding wheels imaginable, and a half-speed buffer with 2 slotted paper wheels for deburring, our FVB and PPC, a BESS sharpness tester, and a laser protractor. He is sharpening for restaurants in the Copenhagen airport and his area, households, scouts etc.




Numbers in his notebook are sharpness of the knives in BESS, for comparison a new utility knife blade scores 150-200, and a disposable shaving razor under 50.
At the top are his notes on the wheels diameter, and Universal Support height for grinding and paper wheels for the knife jig set at 130mm, as calculated by our software.

Michael is very innovative, and we learn a lot from each other; later he may share with us all his method of sharpening serrated knives on grinding wheels of his own design.

An excerpt from his correspondence:
"I am in the process of contacting a teacher at the chiefs school here in Copenhagen that teaches for the chef degree and other kitchen personal...
My goal is to talk and show how knives also can be sharpened and what they should look for when having someone else to sharpen knives - a sharpening service. I have tested one other knife sharpening service to see how there result was - and as my wife said when she looked at the finished knives we got back - "Have they been sharpened?" - was her reaction to the result. She has also tried other sharpening services at work - with bad results too there. So I thought it could be fun to teach these up-coming chiefs to be more quality minded for getting their knives sharp."

Next is another page from his notebook with BESS sharpness numbers for his workload. Impressive, considering that <= 50 BESS is the shaving razor sharpness.
Michael writes:
"I've done a full workflow of sharpening 14 straight knives for a client using 4 Tormek wheels, and 2 paper wheels with 5,0 and 0,5 diamond paste on them and supports. For the fun of it and to see how well the sharpening went I measured all 14 knives. The more I measured the merrier I got. Have a look at the attached.
I just needed to share this with you to tell that following all your sharpening guidelines really pays of to follow! Thank you again for all the efforts you have used to improve the sharpening..."

This is for people who use our software Grinding Angle Setter for Tormek and also have the BESS sharpness tester.

You must have noticed that a 20 dps and 15 dps edge never scores on the sharpness tester as well as the 12 dps, let alone 10 dps edge, despite showing the same keenness in the hanging hair test.
Many a man on this forum put true razor edge on the knives, so can you confirm my observations that the razor sharp edge will score:

10 dps edge near 50 BESS;
12 dps edge 50-70 BESS;
15 dps edge 70-90 BESS; and
20 dps edge near 110-150 BESS.

I am looking for confirmation from others of this "best score by edge angle" pattern.

I was adding an extra Tormek to our workshop, and as we sharpen seated was looking around for a sturdy stand.
Alan from Illinois shared him using a dirt bike stand with me just on time.
By Alan's feedback, I picked a "MX Motocross Dirt Bike Motorbike Static Stand - BLUE" - "blue" of course to match the Tormek colour. Made of moulded plastic, has rubber anti-slip top.
Australian Dollars $60 delivered, in the USA should cost a handful of peanuts.
The top is a good match to the Tormek base in size, and the stand height is 43 cm - right on for my height of 170 cm.





This is an Australian eBay link: https://www.ebay.com.au/itm/NEW-MX-Motocross-Dirt-Bike-Motorbike-Motorcycle-Static-Stand-BLUE/131857146226?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

Photos of the rare knife sharpening machine Tormek-4000 by happy owner Harry from Norway.
Harry has also attached our Frontal Vertical Base to give himself more flexibility in honing on the leather wheel.
Today I finally have time to program software  for his Tormek-4000 for setting grinding and honing angle.

The Tormek-4000 distribution was limited to Europe and... there was one machine in Australia that I missed

When sharpening single-bevel Japanese knives, I used to polish the back flat side on bench stones, then grind the beveled side on Tormek.
But yesterday we got a dozen of single-bevel Japanese knives to do, and I told myself there should be a better way.
And yes, it is. Our new procedure follows.
We are getting 70-90 BESS on the sharpness tester.
Using 2 Tormek machines, one with the Japanese SJ wheel and the FVB, and another with #200 (or #400) and #1000 grinding wheels, it takes 10-15 min per knife.

1. Measure the existing edge angle with a laser protractor, if ordered to reproduce. Our default for quality high-carbon Japanese knives is 16 degrees; lower-end knives we sharpen at 20 degrees.



2. Clamp in a knife jig.
Using our Frontal Vertical Base at the front of the Tormek, position the knife so that the backside edge rests on the wheel with the knife jig parallel to the top of your Tormek.
Polish the flat back on the Japanese wheel SJ-250 horizontally - initially do just 2 passes.
You will get a narrow polished strip all along the edge; don't bother if it is not ideally uniform at this step.




3. Set the grinding angle using our computer software "Grinding Angle Setter".



4. Grind the bevel side into the edge on a coarse wheel, e.g. SG-250 grit 220, or diamond wheel DC-250, or a CBN wheel.



5. Using our Frontal Vertical Base at the front of the Tormek, polish the flat back on the Japanese wheel SJ-250 horizontally; usually 1 pass is OK.



6. With the help of our computer software "Grinding Angle Setter" calculate the Universal Support height for the next grinding wheel.
Grind the bevel side into the edge on a fine wheel, e.g. a 10" Japanese wheel JIS 800, or a diamond or CBN wheel #1000-1200.
Typically it takes 2-4 passes.



7. With the help of our software for the Frontal Vertical Base calculate the Universal Support height for honing on the leather wheel.



8. Hone the beveled side at the edge angle on the Tormek leather wheel with the Tormek honing paste; typically 2-4 passes.



9. Using the Frontal Vertical Base, deburr the flat back on the Japanese wheel SJ-250 by 1 horizontal pass.



10. Finish on a hanging strop by 6-10 passes alternating sides.



11. Test sharpness.

Works like a charm for quality high-carbon knives.
However, with softer knives like Kamikoto etc, requires an extra step to remove the wire edge. We do it by honing on a rock-hard felt wheel on Tormek with 1-micron diamonds @ +3 degree higher than the edge angle, controlled by our FVB, alternating with the flat back of the knife on the same felt freehand at an angle just clearing the knife jig, x 3 passes.

[Al]

Our friend Al from New Zealand sharpens knives by means of exclusively Tormek, the stock SG wheel and leather wheel with the Tormek honing paste.
The knife on the photo has been sharpened at 10 dps on the SG wheel, and considering that the steel it is made of produces a burr "in-between" positive and  negative, honed on the leather wheel at 11.5 dps, as per our deburring recommendations.

Near razor sharp (Gillette razors score 50 on this sharpness tester), and the apex is cleanly deburred of any wire edge.
I am so happy for Al, he beats my own records.

[any knife]

You know that Tormek specs for the T-2 Pro Kitchen state:
"Please note that Tormek T-2 is intended for knife sharpening only. The machine is not compatible with Tormek's range of jigs and accessories."
Knife width is limited to 14–60 mm (9/16"-23/8"), and max thickness is 3.5 mm (1/8").

But not for our inventive customer David from California. David has modified his T-2 into universal Tormek, using 2 parts:
Tormek Horizontal Base XB-100 https://www.tormek.com/international/en/spare-parts/other-spare-parts-and-upgrades/xb-100-horizontal-base;
and our Frontal Vertical Base http://knifegrinders.com.au/11Shop_VB.htm

Now David can sharpen any knife, no matter how wide, long and thick it is, cleavers, woodworking tools, and use any Tormek jig.

At the moment I am programming software for his modified T-2 to set grinding/honing angle.
According to David, "The good news is that this software should work for most any T-2 installation, because the XB-100 will really fit only in that same position, fitting snugly between the housing handle and power switch."

Working with David on his project gives me a pleasant feeling of two shining minds encounter - the one I've had with many of you, but this does not happen often, and is precious moreover so.

With David's permission I post photos of his solution.

Since Rick (RickKrung) sent me his pivot collars half a year ago, I use them whenever I have to sharpen a convex, concave or S-shaped blade.
To grind the target angle using our software, the knife jig protrusion is set at the lowest point of the curve, e.g. at the bottom of the concavity.
Rick's collar provides for uniform bevels and accurate apexing no matter what curves

Today it was a hand-forged damascus skinner from an amateur knifemaker, sent for beveling and sharpening, the edge was 0.5 mm thick; by the end of sharpening this skinner scores 95 BESS - "scary-sharp" by our sharpness chart.




Rick, thank you mate. I honestly say your pivot collar deserves way more attention it has got so far. It makes getting a nice edge easy on all those karambits, persian, kukri and fighting knives with complex curves. Obviously, the concavities are sharpened on a radius wheel or a stock wheel with smoothed corners.

Case study in the Australian Knife Magazine: http://knifegrinders.com.au/Home/issue4_article.pdf
Video-1: https://youtu.be/ZDPXqAK9Xr0
Video-2: https://youtu.be/UckPmizllk0
Video-3: https://youtu.be/3yg_bKczR1E

We call it a METHOD because it has nothing to do with individual sharpening talent.
Actually, everyone in our team is hopeless in freehand sharpening. Freehand sharpening is tranquillizing?! - we find hand sharpening painful, wasteful in time and $, and extremely frustrating.

Everyone should be able to get the same or better sharpness following the process.

We have been using this modified felt wheel for a while for deburring and honing, with excellent feedback from butchers.



This is a rock-hard felt wheel where I cut cross-slots using this Dremel cutting wheel


I run this wheel on a half-speed grinder at 1400 RPM, and thanks to the slots it works like a good fan, cooling the edge as it hones.

I had to think of a powered quick honing method when one butcher commented on the edge we get after the grinding and paper wheels that the "shoulders" as seen in the 2nd edge below somewhat hinder the cut; while he prefers a smoothed V-profile


Felt smooths away the bevel line so well that the edge continues into the blade face seamlessly. My butchers are happy ever since.

Frontal Vertical Base for controlled-angle honing and edge-trailing knife, cleavers and wide blades sharpening.
Compatible with all Tormek models T-4, T-7, T-8, SuperGrind-2000 and "computerized".


Rods are 20 cm long, and one rod is threaded for fine adjustment.

Extended position for sharpening cleavers and wide blades


Angle-controlled honing on the Tormek leather wheel eliminates risk of rounding the cutting edge


Use for honing on a felt wheel with diamond spray


Software to set grinding/honing angle


The desired edge angle is set by vertical distance from the top of the FVB to the top of the Universal Support bar.






YouTube videos:
Knife honing >>
Cleaver sharpening >>
there are more YouTube videos on our channel, and by SHARPCO in Korea, and sharpeners in Germany, Sweden and Italy.

Full details on our website: http://knifegrinders.com.au/11Shop_VB.htm

.

[Sharpening Technique]

Sharpening speed 1-2 min per knife.
Changeable Angle Guides to grind the edge at 20, 24, 30 or 38 degrees included.
An additional set of 5 dps angle guides is used to thin a worn blade.

Sharpening Technique
Pressing the blade against the angle guide, pull the blade from the handle to the tip with a light downwards pressure to contact the grinding wheel.
(Unlike with a stone wheel, pressure should be low for CBN/diamonds to grind effectively.)
Repeat on the opposite side of the wheel, alternating sides till the edge is apexed, then continue on the fine wheel with the same angle setting.

Learning is quick, I had the 3rd knife sharpened under 2 min.

More photos, detailed description and production drawings on our website http://knifegrinders.com.au/05Equipment_volume.htm

We do not sell these attachments.
We share a solution for volume sharpening on Tormek that has been proven to work, and work well.

We take an opportunity to thank Richard Kruger (RickKrung) for his invaluable help through this project, which took us almost 4 months from a vague idea to the working solution.

Please see our last research comparing sharpening high vanadium knives using aluminium oxide versus CBN/diamond abrasives.
This comparison has been done on knives with vanadium content of 1%, 2%, 3%, 4% and 10%.

Link to the report on the BESS forum: Edge Rolling in High Vanadium Knives >
more: Edge retention by hardness, carbon content and wear-resistant alloys >
Printer-friendly version >>

This must be especially interesting for fellow tormekers, as all sharpening was done solely on Tormek machines.

Excerpt:
"Numbers tell us that edge rolling does depend on whether we sharpen with aluminium oxide or CBN/diamond, and CBN/diamond gives better lasting sharpness than aluminium oxide, but correlation with the vanadium content it is not linear – instead, there is a
dramatic rolling in edges with vanadium content of 3% sharpened with aluminium oxide."

"The high-vanadium edge sharpness quickly moves beyond the shaving range to just sharp. In the first impacts a 10% vanadium edge apex rolls to the same extent as a 3%, and both the 3% and 10% vanadium edges lose their initial keenness almost at the same rate as a mainstream knife.
Higher wear-resistant blades win as stayers, but are equal sprinters.
As one of our readers has commented: "Which may explain why s110v loses it's keenness rather quickly but is able to keep a working edge for a long time"

Tormek is a supernaturally robust machine (unlike its clones).
18 years on duty, the SuperGrind 2000 still lasts and lasts, outliving later generations of Tormeks.
When upgraded with only 2 parts: the stainless steel shaft with its Ezy-Lock, and US-105 with micro-adjust, it equals to Tormek T-7 in functionality.

FYI, we've added a sharpness chart to the Sharpening Resources section of our website Sharpness Chart >>
Includes data for all traditional sharpness tests.

Not sure if this is news to the Tormek community, but actual honing wheel LA-220 diameter is 215 mm.
If you set your honing angle at the 220 mark that is in bold on the AngleMaster, you will inevitably round the edge.
Correct is setting it at 215 mark - as shown by the red line on the photo: