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I'm not sure what you are referring to in the drawing, but Delta (as the greek letter) in TormekCalc is the bevel angle in degrees per side.

Z6 is the declared angle, so subtracting half the total blade angle makes sense (dividing I6 by 2 to get the half-thickness in the process), but why divide the difference again ? It looks to me like you're computing :

((Delta-(BladeAngle/2))/2)

Hi. In any case, if you take the arcsine of (J6/2)/I6, you already have the angle in dps (degrees per side), which is what TormekCalc uses, or half the total edge angle. So why would you again divide the result by 2 ?

And as we said before, and as explained in the video, as TormekCalc or Dutchman's formulas are based on projection distance, the (apex) angle you get is independant from blade thickness. However the beam of your laser goniometer has a nonzero radius, so the reading you get will essentially be scattered between the apex angle and whatever angle is measured as the edge of your beam hits the concave grind made by the wheel. The latter angle being higher than the apex angle. This is more likely to happen on a thick blade where concavity is discernible.

It's nice to see they never seem to let their customers down.

Hallo Pietje,

I am not sure what you are referring to, but the angle in TormekCalc (and in Dutchman's tables for that matter) is the angle at the apex when the apex is centered and aligned with the center of the jig shaft.
So the thickness of the blade has no impact... other than the well-known issue with the SVM-45 not being self aligning.

There is also an issue when the wheels you go from a wheel with a smaller radius to a wheel with a larger one, and there are tools in the spreadsheet to help you optimize your time and still end up with the right angle.

Hello,

Could you reference the specific knives you are talking about ? Most Global knives AFAIK have a symmetric edge. I have about ten of those and I sharpen them as any other knife.

Some traditional japanese knives (deba, yanagiba) and maybe a couple other such as the chopper have single-sided bevel and a hollow back. Those cannot be properly sharpened on a Tormek unless you want to completely mess up the shape of the blade. They are designed to be easily sharpened manually on a flat sharpening stone. Doing so is much easier than sharpening a thin-beveled western knife on a stone, as the knife serves as a natural guide.

I know of several brands of japanese knives (Misono, Suisin, and many others) where the edge is symmetrical in terms of angle, but not in terms of number of passes (they often mention 70-30). Maybe Global started doing this too. In that case, the knife has a noticeably smaller bevel on the left side, sometimes akin to a microbevel. I suggest sharpening those with a 3-to-1 ratio for right side vs left side first. Check your progress often to make sure you're keeping the same aspect. I am not skilled enough at cutting vegetables to notice any difference for a 70-30 vs 50-50 ratio on a thin knife such as a gyutou or a suji.

Hi Rich.  It would free up both hands to position the blade flat before starting the wheel lowering the risk of error in engaging the face to the wheel.

I might be wrong, but it seems to me like a very bad idea: the still wheel with no water running over it has a much higher friction coefficient than when it's already running. So there is a much higher risk for the blade to catch, messing up the blade and potentially injuring you.

Gloves are advised against in the safety instructions of the Tormek (top of page 6).

Hey everyone !

Best wishes to all of you for 2024 !

Among my SVM jigs are three pre 1992 jigs purchased used which allow me to standardize on 139mm projection, even with paring knives.

It's a shame those shafts have gotten shorter. A drill collar or milled pin-pivot-style or 3D-printed handle is quite helpful to standardize projection distance as well.

It will also depend on how you get ahold of the T-8 in the first place. The standard T-8 comes with the SG, the T-8 Custom is basically barebones.

If you got yourself a bargain on a used T-8 with no stone, then it will get down to what kind of finish you want. A trued SB will take quite some time to get nice and even, and will never give you the fine-graded-SG finish. SB on knives will have a much different feedback than the SG, I personally don't like it. Also the SB is not meant to be faster than the SG on standard steel (see this wheel comparison page, and whatever video went in depth over wheel selection)

Now if you're eyeing a T-8 custom with either stone, I think you should look at the overall price of the T-8 Custom plus stone, plus jigs, plus truing tool, plus honing wheel, plus honing compound (if non-composite honing wheel), ... And you might solve your dilemma by going with standard T-8 with SB/DF stone.

I'm not sure we can do much, aside from laying down facts on why this is desirable, and more generally constructive criticism.

When faced with such comments, Tormek seems to follow the usual stages of (commercial) grief, beginning with denial, and sometimes ending up accepting the issue and doing something about it (The AngleMaster for knives and the FVB/MB-102 being two excellent examples of this).

Now to be realistic, we have to admit that :
- It takes a lot of money to develop a new (high quality) jig, that can be reliably produced at a reasonable price.
- The number of people that this is a problem for are probably a few dozens and will never buy enough jigs to make such a redesign economically viable
- Knife sharpening is an afterthought for Tormek, but the market size is big enough that they have been putting a lot of effort to adress it better

So all in all, I think the KJ has been developed with the objective of adressing the assymetrical bevel issue, at a time when Tormek was still asserting that the best way to set a predefined angle was the AngleMaster. So they wouldn't bother with including a way to set a projection distance, because as they put it in a video at the time "in the end it doesn't matter", and they -understandably - wanted to keep the KJ cost as low as possible. Denial stage, remember ?

Therefore however loudly we protest, it won't change much in the near future, when the non-recurring costs for developing the KJ have to be covered tenfold before they dare think of redesigning a jig.

I might even go as far as saying that they consider angle calculators some kind of a threat, and they dismiss their interest in patent filings, writing : "There may be errors in computation-based solutions". As if that was not true of just any human action, be it through software or hardware. So it is quite convenient for them to produce a new jig that will de facto negate the interest of calculators.

My best guess is there will be a market for third-party jigs that allow to adjust projection distance on a larger scale than the SVM, with a more reliable way to prevent this distance from changing during sharpening, and with a way to guarantee symetrical clamping. At a much higher price.

AFAIC, I've stocked on SVMs and I deal with assymetry for wide knives by sharpening one side, then the other, fiddling with the USB height and a controlled number of turns one way and the other. I don't sharpen enough of these that it is worth losing time to reset USB height for each knife.

Ken,

I am not sure what you are replying to. The sentence that prompted my initial comment which you disagreed with was :

I would buy a T-2 plus the coarse wheel for a mobile knife sharpening business.

If a professional sharpener is not willing to invest time and money in professional equipment I am not sure this is going to end well. The members of the culinary teams are cooks, not professional sharpeners.

Never did I say the T-8 fitted everyone's budget or needs, nor that Tormek released low quality equipment 

The important detail is to make sure that whatever part of the knife is touching the stone should be the same distance from the support bar. This is why it is important to "lift" the knife handle, not rotate it.

I'm not sure I follow you : if your edge curves upwards (as on most western chef knives) and you lift, you get closer to the USB, don't you ?

One trick that Tormek suggest is to get a square and draw a line across the wheel. Position the line so that the edge of the knife is resting on the line then without turning on the machine draw the knife across the wheel as if you are sharpening and make sure that the edge touching the wheel is always touching the line you drew on the wheel. This way you will see how you need to move the knife when actually sharpening.

As shown by Tormek at this point in time in the advanced sharpening video, if you only lift you can't follow the line (except on a nakiri-type knife obviously). I think Wolfgang sums it all when he says "You can have any jig you want, you have to control and train these movements". But as mentioned in numerous other posts (look for "pivot jig") pivoting is not ideal either. Control and training make sharpening on a Tormek an acquired skill.

Although I see where you are coming from, I feel some of your information is outdated or not really applicable.

Read today, on Tormek's Website :

Tormek has developed a sharpening machine specifically designed for sharpening chef's knives – on site in the restaurant kitchen.

So it seems that the recommended use case for the T-2, as @Carly mentioned in their initial post is indeed chefs who want a quick, sharp result on site. It doesn't sound *that* outdated.

The T2 can also sharpen several kitchen accessories, as shown in the linked video. The T8 can not sharpen these.

Yes, mostly because there is no Tormek-made "platform jig" suitable for knives for the T-8, but as proven on this very forum, it would solve the S-knife issue. And also no rotary cutter jig for the T-8, but again more of a marketing choice than an actual technical issue.

By "the result will not be that good looking" do you mean an uneven bevel or will have scratches? Starting at 9:00 on the video, Johan demonstrates the knife he sharpened has an even bevel.Yes, it is a different technique, notusing tilt; however, it achieves the same even bevels.

I mean uneven bevels. The T-2 is a constant angle sharpener. We know full well that keeping a constant angle will usually (ie on most kitchen knives) result in a bevel that widens at the tip. Granted, there is no sharpness issue (it might even improve it a bit), it is just about looks. But it is the very reason why Tormek recommends to lift, not pivot. You can't have it both ways, geometry is kinda stubborn.
To be crystal clear, if you take a chef knife with an even-looking bevel and sharpen it on the T-2 using the sharpie trick in the middle of the blade, you will most likely witness that in the tip area you only remove sharpie on the shoulders, not all the way to the apex.
Some knives, geometry allowing, will be fine that way, some might even get a narrower bevel, if the spine is curving down insted of the edge curving up, while the tip area of the blade gets quite thin. But you don't control
that with the T-2, the "Advanced sharpening technique" video intro with all the edge geometries is precisely about all this.

I do not believe that, especially after extensive testing, Tormek would sell a product which would not meet its high quality standards.

I don't think I ever implied otherwise, I just find it odd that several topics tend to promote the T-2 as a good complement to a T-8 for a sharpening business, and try to counter geometrical arguments with "Tormek sells good products". As examplified here.

It's interesting that you're getting a wider bevel at the tip.  The normal result, if you follow Tormek's general advice to move the jig parallel to the USB and only lift your elbow to hit the belly/tip, is a smaller bevel.  That's because the bevel angle gets steeper as you get higher on the wheel.  Are you using that method, or are you pivoting the jig?

Although it's true that you will get a wider bevel if you don't lift and pivot the tip away from the USB, I found that depending on the shape of the blade itself (taper angle and edge curvature mostly), sometimes lifting is not enough and you have to pivot the tip closer to the USB to get the steeper angle required to keep the width even (reverse-pivot).

That also depends on where along the blade you clamp the jig. It helps maintain control in the tip area where lifting only might result in so little of the blade contacting the wheel that it ends up messing up the tip. The sharpie is your best friend when trying to find that sweet-spot combination of lifting and pivoting one way or the other.

Although they say little about this pivoting in the videos, you can see Wolfgang pivot one way or the other if you watch closely of some of them. He explains why in the advanced sharpening video, when he explains the different kinds of blade geometries.