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I wanted a second SVD-186R and remembered that there had been a discussion of this when the R was released with its locking knob. I had a 186 on hand so for the conversion to a 186R I implemented Rick's idea of a collar around the jig to reinforce the tapped hole.

As can be seen in the pictures, the body of the 186 is about 2.5mm thick and the collar doubled that. There is now plenty of thread to hold the knob. (If I were Rick I would have machined a steel collar, but the 20mm ID brass bushing was so cheap ($6) and easy that I couldn't resist; I am confident that it will do the job.)

The brass bushing was a decent interference fit over the jig: I warmed the bushing, froze the jig, slid on the bushing and it tightened up nicely. If the fit hadn't been so nice, I would have put a dab of JB Weld in to keep things orderly.

Though it looks a bit bulkier in the middle, I am finding the homemade 186R to be functionally the same as my "real" 186R, so this was a successful modification for me.

Gord

Thanks for that info. I realize that it is extravagant to have dedicated machines, but if I can get a T1 here in Canada, I would likely leave my T8 set up for my turning gouges (it sites beside my lathe) most of the time. Then the T1 would be for kitchen knives, unless something special needed to be done. One thing that the T1 doesn't do is very small or short blades, and I have ways to do that on the T8, so that would remain a job for the T8.

I personally use the tip area of my knives a lot. The T1 will only sharpen the shoulders of the tip area for reasons mentioned in some other threads, so I came to the conclusion that mixing T8 and T1 was not the best idea.

I am curious: There is no doubt that mixing T8 and T1 would require some thought and might be best avoided, but if (as with many of us) you often use the tip of kitchen knives, would you not prefer a constant angle out to the tip (i.e. keep it as acute as the rest of the blade)? This of course can be done on the T8, but the fact that it is achieved automatically by the design of the T1 / T2 is an attractive feature to me, making it perhaps the only machine for my kitchen knives unless something major needs to be done. Am I missing something?

My .02... Herman's Knife Jig is the better idea.

That was my first thought when I watched the video--very clever, but I would find a platform jig to be so much better for this. While I agree with Ken that the wooden jig in this video might be easier to make for someone without tools to work with metal, a platform jig is pretty easy to make and I think it is so much better a solution that one should be in every knife sharpener's arsenal.

At the risk of irritating those who didn't get one before they went out of production, I will note that the Hewn & Hone small knife jig was invented for small--even tiny--blades (specifically for small sloyd blades for carving) on the Tormek and works like a charm for me. It is self-centring into the bargain. It is like a mini SVM-45, or, because it is self-centring, functionally like a mini KJ-45, so it does not have the imprecision that some find problematic in the rubber strap Tormek Small Knife jig. In an ideal world Tormek would make a mini KJ-45 for small blades.

I want a T1 for the reasons Ken has stated, with this nuance: For me, it is not even what is sufficient for the task at hand, but what I will actually use. If I start skinning a fish and realize that the knife is not as sharp as I want it, and to sharpen it I have to go down to the shop and set up my T8, I will just press ahead with the not-sharp edge and accept a sub-par skinning job. If I can just step over to a T1 on the counter, switch it on and do a quick sharpening, that is what I will do. Or, more likely, I will do it before I even start to skin the fish.

I won't expect the edge to be as perfect as with the guided honing I can do on my T8, but with a fish that needs to get into the pan pronto, I won't ever get to the T8. So the T1 fits the bill for me, as a setup I will actually use when I have a job to do now and haven't got a sharp knife to hand. This is an expensive compensation for not keeping all my knives sharp, but I like playing with sharpening stuff anyway, so I will expect to get some value out of that too. If I want to be a sashimi chef for an evening, I might remember to plan ahead and use the T8.

Characteristically, Tormek is moving at a glacial pace to get a distributor for the T1 and T2 in Canada, so I hope to get a T1 shipped up here from Sharpening Supplies.

It's a shame that they didn't make the new jig adjustable for projection distance.  I don't see a compelling reason for them to have left that out.

Tormek evidently decided that a split shaft made of a composite material was the best approach for their self-centring jig. This is not compatible with an adjustable collar, so one or the other had to go. The same distance-to-the-wheel adjustment that is made with the collar can be made with the USB (albeit less conveniently if you are doing multiple knives). And the SVMs are still around for those who prefer the adjustable collar.

So, it looks like it was just one of those design compromises.

There are self-centring jigs for other sharpening systems that do not use a split collar, and a few after-market ones for the Tormek. With these, there is a solid shaft that can accommodate an adjustable collar. (I did a post several years ago on quite a good one for the Tormek from Hewn and Hone, unfortunately no longer in production. I still use it, and a TSProf jig that I modified.) I don't know why Tormek did not follow one of those approaches. They might have worried about patents on the other designs or they might have concluded that the split collar design was superior.

Though I have been frustrated by the length of time that it took Tormek to come up with a self-centring jig, I am going to give it some time to see how it works, for me and others, before I make a judgment on the one they have designed.

Ken, if your query is about when it might be sensible to convert (regrind) a flat or hollow ground knife to convex, I can't think of it ever being worth it for me. There are excellent suppliers of convex ground knives (e.g. Bark River) and few of us are going to get close to the near-flawless convex grinds that they put on their knives at the factory. If we do, it will be on a slack belt, not a wheel. (Convex-ground knives do tend to be on the expensive end of the scale, and someone on a budget might convert a hefty-but-economical Mora (scandi grind) to convex to avoid the expense of a pricey Bark River or Fallkniven. I would just keep the scandi grind, but if I wanted an inexpensive convex, that is what I would do, and I would do it on a belt.)

With that said, some knife people like a convex micro bevel on whatever grind they have, and the KJ-45 might be able to do that without too much work, I am keeping an open mind until I get the jig. I expect to use both the KJs and SVMs unless I find one to be superior in all applications, which would surprise me.

Gord

Hand-sharpening these little paring knives on a flat stone produces the best result for me, and I find that it is faster than fussing with jigs. The blade achieves its excellent paring ability by the thinness of the blade. Though the website picture of the grind shows a gentle convexity, I think that this might be to illustrate the point they are trying to make about the blade staying sharp as its metal disappears over time. When I look at mine, they are a full flat grind. I maintain the grind the way you are doing it now (flat on the stone with slight extra pressure on the edge). In the long run this will introduce a slight convexity but the blade is so thin that convexity or even a micro bevel will not diminish the paring ability (and a little micro bevel might improve edge retention). I note that the Herder website shows sharpening with a honing rod at an angle that will clearly produce a micro bevel.  By the way, I (and others with this knife) sometimes whittle back the handle 4-5mm, at least on the cutting side, to improve access to the edge.

I think the lift vs pivot issue is pretty much settled. We all know it depends on the individual geometry of each blade, and the clamping position. In the "advanced sharpening" video, Wolfgang explains that sometimes he has to pivot one way or the other. I personally understand it as :

"When beginning to sharpen on the Tormek, just lift and you can't go (very) wrong. When you're more confident with your skills and muscle memory, look at the scratch pattern/sharpie residue and pivot whichever way necessary to achieve desired edge".

Cheers,

Nick.

While I agree with the summary that Nick gives here (stick to lifting until you are experienced; then pivot if it helps you get the edge you want), I would not say that lift vs pivot is settled. Tormek has consistently--in old (Farris, Holtham) and new (Knife Sharpening Part 1, Advanced Knife Sharpening) videos--instructed "lift-don't-pivot". Pivoting is described as "the common error" and "the basic error" that causes problems (over-wide bevels and too-acute angles) on the curved parts of blades (see e.g. Knife Sharpening Part 1 at 28-31 mins).

And yet many of us want to pivot, at least in some circumstances.

When I watch closely, the pivoting that I see Wolfgang (who is helpfully candid) suggest in the Advanced Knife Sharpening class (at about 32 mins) is the opposite of pivoting to follow the curve. He notes that it can be helpful to pivot the handle AWAY from the bar (as I say, the opposite of following the curve) while lifting, to maintain the desired angle. I don't think that Wolfgang would describe this necessary, but rather as a way that might be easier or more intuitive for some than pure lifting which, if taken to excess, can lead to rounded tips. (Later in the class, at about 35 mins, Wolfgang also puts the SVM-45 guide on one of its corners so that he can follow the straight edge, but this is a static position, he is not pivoting in a curve. One senses that, as noted in his Facebook post, he sometimes finds the straight-backed collar restricting.)

Though I have and use Rick's pivoting collar (and designed one myself that I see is now sold by the sharpening outlets), I would rather not pivot if I could learn how to avoid it. I am not an expert at geometry, but it seems to me that any angle can be maintained just by lifting: in theory, if done in the correct amount, the lifting could exactly offset the change in angle caused by the movement of the edge traveling closer to the bar as the curve passes over the wheel. That might be more theoretical than doable in practice, but if the theory is at least true, then the practice should get better with experience.

I once asked Tormek Support to help us with a clear answer to whether pivoting was EVER required to maintain either a consistent edge apex angle or a consistent bevel width (whichever is your objective). I got no response at all to my email. Maybe one of the geometricians on this forum can help answer that question.

Gord

I follow Max on YouTube (he is a bushcrafter / spooncarver / toolmaker) and when I saw this video I thought of posting it here, but I thought "Oh God, here we go again with pivot vs lift". At 6:45-8:00 he actually describes the rounded front stop on the KJ-45 as a Tormek feature designed to allow pivoting for broadly-curved knives. That is not how I heard the front stop described in the Tormek video. I would be surprised if Tormek designed the front stop with its narrow/rounded face for that purpose, or would suggest it be used that way (though I might do so). And yet, as you say Ken, when he sharpens his Mora, he does follow the Tormek method pretty closely, because it is a relatively straight blade. He has a nice slow-and-steady technique and gets good results.

As Ken posits, the value proposition (time/steel used vs. utility of knife) of a convex grind depends on the intended use. The fellow whose YouTube video I linked earlier (Virtuovice) has a number of quite carefully documented tests of different convex and scandi grinds specifically for bushcraft uses such as featherstick-making, splitting kindling ("batonning") and cleaning game.

For example, in making a featherstick to start a campfire, he demonstrates how the concave edge is superior (in his view) given the rotation of the wrist as it moves down the stick. He does time trials and examines the quality of the result. (He is somewhat obsessive about it, but he seems to know that.) Also, he field-butchers the deer he hunts (in Japan) and is quite particular about the specific convex grinds on his various hunting knives, which he finds better because they don't nick the bones as much (he is a surgeon in his day job, so I accept his views on this).

One of the features of a convex grind that is said to be helpful for splitting and carving tasks is that the thickness behind the apex pushes the material away which (a) aids in the task at hand, which involves physically separating the material and (b) keeps the apex away from the material for the completion of the cut, which stops the apex from dulling unnecessarily. Obviously, this is not what you want for many blade uses, but it is said to be an advantage for those particular uses.

DLT Trading (Bark River Knives) is one of the champions of the convex grind. Owner Mike Stewart is pretty adamant about the advantages of the convex grind. If anyone wants to hear his case, here is a link to one of his videos. Knife makers typically use a slack belt to make a convex edge, but in this video Mike Stewart notes that it was originally done on large grinding wheels by rocking the blade back and forth:

https://www.youtube.com/watch?v=lkV32RmQOXA&ab_channel=DLTTrading%2CLLC.

Gord

"On a practical basis, how many knives would really benefit from having a convexed edge compared with the shallow concave standard edge of a Tormek wheel? Ken"

Ken, as you doubtless know, there are big "convex vs concave" (and "flat vs everything") debates on the knife forums. I have a convex bushcraft knife that I feel does all of its bushcraft tasks (including staying sharp) better for me than my scandi bushcraft knives (which I also love). But I would agree with tgbto that the advantages of convex edges--if the ones suggested in the debates are real--are likely to be most pronounced on thick blades, such as bushcraft knives and cleavers.

Though one of the other threads on the new KJ-45 knife jig queried whether one could get a smooth convex bevel on a Tormek, I think it should be quite doable, especially if one begins with a sufficiently coarse wheel. I note that the Japanese surgeon with the YouTube channel "virtuovice", who is one of the big champions of convex bevels (on hunting and bushcraft knives), does it by hand on waterstones. It is painful to watch how long it takes him, but he is a master at it. Here is a link to one of his videos, in which he propounds a theory in support of the superior toughness of a convex edge.

https://www.youtube.com/watch?v=XA5AM2Lb0iY&ab_channel=virtuovice

Gord

I will definitely want one of these if it makes it to production.  But I am wondering, does this have advantages over self-centring jaws, or has it been designed because no satisfactory design for self-centring jaws has emerged?

Gord

In case it is useful for people looking to hang wheels on 12mm stainless steel bars (which I can't get in supposedly metric Canada without a special order from my local metal supplier), note that Lee Valley has drawer / cupboard handles made with 12mm SS bars as long as ~40".  I cut off the ends to get simple 12mm bars for Tormek-sized supports and jigs.  Here is a link:

http://www.leevalley.com/en/hardware/Page.aspx?p=46331&cat=3,70806,43521,43538

Gord

I have never done a cleaver, so mine is always pretty close to the body of my T8.  (N.B. For my FVB I used 12mm X 200mm SS bolts (with threads only at the end) and cut off the heads.  They are plenty long, longer than I can imagine ever needing them.)