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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

I thought I should let you know that we have only 1 Pin Pivot Collar available through our website, and have no plans of making more.
Successful design of Rick.
100+ happy users around the world.

We hardly ever use firm strops in our knife sharpening. The Tormek leather wheel, paper wheels and hard felt wheels cover all honing and stropping we may need. But we do use hanging strops for their help with the wire edge removal, plain w/o honing compounds. We use it plain because when we take the knife to the hanging strop, it has already been honed on the wheels. Someone who does not hone on the wheels, may be using the hanging strop with honing compounds.

[tail]

Josu, the hanging strop "gives" as we drag the blade, and thanks to that stropping goes at a higher angle removing the wire edge, if any.
The firm strop cannot do it.

I borrowed this technique from the straight razor sharpening - they hone the razors on firm strops with Chromium Oxide or other fine compound, and finish by 10-14 strokes on a hanging leather or linen strop. Straight razor steel can be likened to mainstream knives.

On a smooth horse or cow hanging strop, the sharpness tester shows improvement in the edge of mainstream knives after 4 strokes; we normally do 6 - 10 stropping strokes alternating sides. Wear-resistant "premium" knife steels do not show such improvement on the horse/cow hanging strop, but do show on the Kangaroo tail strop thanks to its texture.

You know that we hone on paper wheels, finishing on the 0.25-micron diamonds + Cr2O3 wheel. But some knives, after the finishing paper wheel,  show worsened score on the sharpness tester even though they show improved keenness in conventional tests like hanging hair tests. This happens because with some knife steels the intensive honing on the paper wheel over-thins the edge near the apex. These knives we finish on the hanging strop instead as it gives a stronger apex.

In your Spain the bull leather from Corrida can make a good hanging strop
On the photo is a quick hanging strop that takes no time to make and works for knives:

Following Wootz's explains, and bought two more leather wheels, and actually have three. Both
One with Tormek Honing Compound PA-70.
Other One with Diamond Compound 1 Micron
And other with one layer of Chromium Oxide, and a second layer with Diamond Compound 0.25 Micron.
Both of them are Tormek LA-220 Leather Honing Wheel.

First I proceed to sharpening the knife with one of the grinding wheels that I have. Depending on the quality and / or the kind of steel, I use from SG-250 to the Tormek Diamond wheels DF-250 and DE-250.

Then I use the first leather Wheel with Tormek honing compound in the same angle that the sharpening. I use the FVB and the APP for this.
Then, I use the second leather wheel with 0.1 Micron diamond compound and set the angle between 0.1 to 2 degrees more, depending on the kind of steel.
Two small and soft passes.
Then, I use the last honing wheel one more pass in the same angle as the second.
And finally,  I set the initial angle again and one more pass very slowly and very softly.

Is important to clean the knife between different leather wheels in order to prevent cross contamination between different honing compounds.

I´m note sure if this procedure is exactly the best but the results are fantastics.
Probably, Mr. Wootz will be able to correct something to me, but that is the procedure that I have understood after reading a lot of what he has written and after reading his book.
Please note that the English language is has some difficulties for me and I may not have understood everything correctly.

Regards

Perfect. Thank you for sharing, Josu

Yes. I position the knife jig on the FVB so that the backside edge sits flat on the SJ wheel.
When developing the protocol, I even checked with the Angle Cube the knife jig is at 0 degrees, i.e. parallel to the top of the Tormek.
Where the single-bevel knife has Urasuki, the concave backside, we get only 1 mm polished near the edge.

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.

We reduce the TT-50 play with cable ties - please see this thread:
https://forum.tormek.com/index.php?topic=3053.msg16372#msg16372

Well, thanks to all for your info and comments.
I'm  (un)fortunately living in the EU, and the total cost of the jig/postage/tariff/bank transfer charge and so on made me think twice.
Not happy at all with that, but as a newbie, I couldn't  really appreciate how this device would make my sharpening experience with respect to the total price tag.
Your comments are most welcome.

A couple of hundreds use our FVB with their Tormeks, all models, around the world.
Yet we encourage everyone to make the Frontal Vertical Base themselves, we can program Windows and MacBook/MacAir software for your home-made FVB, how to order the applet is on our website.

Our current FVB base is 25 mm thick, 50 x 107 mm; the legs are 190-200 mm.

Our historically first prototype was of wood; for Tormek T-7 we used to make it of the BGM-100 kit - for details see the thread
https://forum.tormek.com/index.php?topic=2583

More examples of home-made FVB: http://knifegrinders.com.au/FVB_self-made.htm

[mark the wheel and then always mount it in the same position]

By the way, do you know why Tormek stone wheels never run round out of the box, even if they are perfectly round in shape?

Yesterday we were measuring the arbor hole (bore) in the wheels, using a Telescopic Gauge Micrometer.
The stone wheel hole diameter showed 12.11 mm.
While the Tormek shaft diameter, measured with a micrometer, is within 12 - 12.01 mm.
The SG, SB and SJ wheel arbor hole is made a bit wider on purpose, for the ease of mounting and so that the wheel won't get stuck on the shaft if left sitting on it for prolonged period.

You see now why you have to true every new wheel?
When you mount the wheel, it will sit on the shaft a little off its center, and because of that will be rotating out of round.
To make the wheel run round, when truing the new wheel, we are to mark the wheel and then always mount it in the same position.

Alf, we've all been there with thicker knives. The fact is that no slow wet grinder, Tormek or else, has a self-centering knife jig.
Any local machining shop at your place should be able to mill the 0.5 mm and 1 mm recess for you, using an end-mill. Bring the 2 knife jigs to them disassembled, give them only the lower static part, and draw a line in front of the pins with a permanent marker to show them where to mill. It is a 5 min job for the machinist/turner.
Show them a photo from my website to illustrate what is be done: http://knifegrinders.com.au/05Equipment_jigs.htm

For the bevel not to widen towards the tip, clamp the knife not in the center of the blade, but closer to the tip - this is explained in the Tormek manual.

What we are saying is that if you now flip the knife jig and run the other side of the blade on the stone, the grind line will be higher; the grinds be of different height on the sides of the blade. Thick blades (i.e. where the blade centerline is above the jig centerline) get a higher bevel on the base side.

Sure, that's the way it is.
By my experience, leather works well with diamonds up to 2-3 microns, while paper wheels up to 10 microns.

[Erivan]

Erivan, I've seen Tormek leather wheels that are too rough to be usable. This does not happen often, might be just your bad luck to get such a wheel. Well, my luck as well, as of 3 Tormeks in our workshop one came with the rough leather wheel.
It is easy to fix by sanding with #400 sandpaper on a wooden block.
Having finished sanding, wipe the wheel with a rag wet with WD-40 or any light oil to remove the sanding abrasive particles off the leather.

Diamond and CBN based compounds cause deep and narrow scratches on the edge bevels, while conventional abrasives (aluminium oxide, silicon carbide, chromium oxide etc) – shallow; when mirror finish is the goal, bevels should be honed with conventional abrasives.

BTW, if yo are not happy with the honing compound on your leather wheel, you can change it by removing with WD-40 and lots of rags