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Gord,

Thanks for taking the time to share your thoughts and experiences through such a thorough report. I've received mine as well and was quite happy with how it worked on a Mora 106. I have another Mora 120 that I'll eventually use with it and look forward to comparing the results and experience with the Hewn & Hone jig to that of the SVM-45 + SVM-00 that I used for my first-to-regrind 120.

I also tried it to hold a hand forged puukko, but that did not work out. The blade's rhombic cross section was not a good match for the jaws. That's not a surprise though, and is not what the jig was designed for. I only mention it to point out that it's not a magic bullet for all scandi-ground knives.

I'm pleased you had success with it holding a medium-sized pocket knife blade. I have not yet tried that, but I'll keep it in mind as a possibility.

Greg

Hey Gord, that's really slick! Thanks for sharing the idea and instructions.

Does anyone use green compound on the honing wheel?

That's a good question and I'm looking forward to hearing from others.

FWIW, I was already using Tormek honing paste on one of my flat strops before I owned a Tormek and found that it worked better for me than the no-name green compound I was using on another.

You're probably fine just continuing to add honing compound as necessary. The consensus seems to be that too little oil (some use none) is far better than too much. See the Conditioning the honing wheel thread for more discussion.

I can't speak to chisels, but I really like stropping with the honing wheel for knives. I frequently strop my whittling knives—pocketknives and small carving knives—and I've been getting better results more quickly with the honing wheel than I was with flat strops. I suspect this is because (1) the wheel ends up giving more distance traveled over the leather and (2) I can hold a more consistent freehand angle when the knife is relatively stationary.

I'm also very happy with the results I'm getting on my kitchen knives. So much so that I'm going to try an experiment and stop steeling them and instead give them all weekly stroppings on the honing wheel. I've curious to see how that goes. Does anyone else do that?

In the interest of full disclosure, I should report that I did round the edge of one non-whittling pocketknife blade, so your concerns are not unfounded. In this case I was working in dim light, without my reading glasses, and rushing a bit.  The lesson has been learned and I don't expect it to happen again.

I haven't tried stropping with a jig yet, but I'll have to read those wootz reports and give it a try. Thanks for the links, Rick.

Update: I decided to try more careful stropping of the knife I mentioned that had a rounded edge. It's now back to cleanly slicing phone book paper in both directions, so I don't think I did too much damage to the edge before.

CB, great idea, both for the clamp and for the thread!

I may have to dust off my old Lansky just to say I've tried it...

Neat! Thanks for giving it a try and sharing your initial impressions.

I'm curious: when grinding with the side of the wheel, do you need to limit yourself to the portion of the wheel that travels through the water, or is the full side available for use?

Nice clarification, indeed. Thanks Gord and CB!

Marc, I'm glad you're going to give it a try. I'm not aware of any videos covering the full process, but the Dala Horse video and the Hewn & Hone Sloyd Jig Instructional Video both show examples of creating the hollow with different jigs. I know some people do it freehand as well. I'd like to build that skill, but haven't yet.

For the flats, it's the same as sharpening a flat zero grind.

I'm not sure if it's been mentioned... freehand sharpening is usually done with the wheel turning away from the edge (like honing on the leather wheel).

Oh yes, good point. And with the USB in horizontal position I assume?

Thanks for the suggestion of using the USB for support while freehand sharpening, Ken. That had not occurred to me, even though I do that when using the stone grader. I tried freehanding without support a week or so ago for a a quick touch up to a small blade and found that I'd need a lot more practice to hold a stable position. I can see how using the USB support could make a big difference. I'll try that the next time I try freehand.

Herman's platform, or something similar, is what I have in mind when I get around to making one.

I do believe that the SVM-00 is applicable beyond just wood-handled carving knives. The Sharpen small knives with the Tormek Small Knife Holder SVM-00 promotional video from Tormek shows a folding pocket knife with a single centered blade. With a bit of ingenuity, I'd hope it can be made to work with offset blades as well, at least with larger blades. For smaller blades, like the pen blade on the Swiss Army Knife that CB showed above, I wouldn't be surprised if freehand is still the way to go.

Greg, I have read your post with great interest because I have quite new Mora 120 carving knife which I have not sharpen yet. The blade of my knife is made of laminated carbon steel, the core hardness is 58 to 60 HRC. On the bevel you can see where the hard core begins.

In my understanding the new Multi Base MB100 and the side coated diamond wheel would allow to sharpen the flat Scandi grind directly on Tormek machine. Correct?

Jan

Hi Jan,

The blades of my Mora 120s (and my 106) are the laminated ones you describe. I like them.

I have the same understanding as you about the MB100 and diamond wheels, but I have neither. I would be interested in hearing how it goes if you or anyone else tries it.

Greg

I've now used the Tormek to help sharpen a couple of scandi-ground knives and would like to contribute some thoughts to this thread.

I want to start by saying that, like Marc, I use my scandi-ground knives for woodcarving and any concavity in the edge—even that from a microbevel—is noticeable and adversely affects the carving performance [1]. Also like Marc, I've found that a flat zero grind works well for me for the non-woodworking tasks for which I use a scandi-ground knife like a puukko. I recognize that others have different use patterns and preferences and a microbevel or other style of grinding/sharpening may be more appropriate for them, but comparison with the flat zero grind is the context of this post.

The shallow hollow produced by the Tormek does not bother me. At least not when there are small flats added to it by honing the edge and shoulder of the bevel. I first came across the concept of a "flat over hollow" grind for slöjd knives in the context of green wood spoon carving. This style of sharpening begins with using a wheel to grind a hollow bevel and finishes with using flat stones to hone small flat areas at the apex and shoulder of the bevel. Resharpening is accomplished just with flat stones until the edge becomes convex, and then a new hollow is ground.

It appears that this is a time-honored way of sharpening scandi-ground knives for woodcarving, at least in Sweden. The late master Swedish carver, Wille Sundqvist, has an extensive chapter on sharpening in his book Swedish Carving Techniques and this flat over hollow style of sharpening is what he describes for both knives and axes [2]. He distinguishes the grinding step (done on a wet wheel) from the honing step (done on flat stones). On page 34, he says that "it's an advantage to grind knives on a large-diameter grindstone, such as 250mm to 600mm (18 in. to 24 in.)", but also says on page 35 that "[t]he Tormek grinder pictured below is a good one, in spite of the small 250mm (10-in.) stone". I'm not sure which model of Tormek is pictured, but it's an old one: the English translation of his book is Copyright 1990.

I like this way of looking at it, excerpted from page 40:

"The slight hollow grind you get on the bevel when using a large-diameter stone is no problem. In fact it probably serves as proof that the bevel is not convex. A slightly concave bevel can be honed many times without becoming convex."

This is how I've sharpened both a Mora 120 that I use for woodcarving and a Marttiini Lynx Lumberjack that I use a bit for carving, but mostly for general-purpose use around the house and in the garden. The Mora 120 works great. In side-by-side comparisons, its carving performance has been indistinguishable from that of another Mora 120 which has a true flat zero grind. For this use, I'm sold.

I haven't really put the Lynx Lumberjack through its paces yet with the new edge, but I'm very happy with how it has tackled slicing cheese and salami and breaking down a cardboard pizza box. Neither of those are my typical uses for the knife, but it was handy and I thought I'd give it a try. I also used it to trim some relatively hard, but not brittle, plastic pieces today and the edge seems no worse for wear. I'll need more long term experience with this knife before I'm ready to cast a final verdict, but so far I'm enjoying using it.

In summary, I'm quite happy with this approach of using the Tormek to relatively quickly establish the hollow and then using stones to relatively quickly hone small flats. I have another puukko knife that came with a microbevel and I'll be using this technique to remove it rather than going through the work of grinding it out with flat stones.

Note that it does take a bit of practice to get the grind right on such a large bevel, so I'd offer the usual advice of practicing on a knife that isn't precious to you. You don't have grind perfectly up to the apex, by the way, just close enough to be able to finish with flat stones.

Finally, with respect to its aesthetics, I personally like the contrast of the highly polished flats against the fine scratch pattern in the hollow left after a few passes at fine grading.



Edited to add sharpening notes:
- Mora 120—sharpened using SVM-45 + SVM-00. Required lifting only. Required adjusting the SVM-45 separately for each side.
- Marttiini Lynx Lumberjack—sharpened using the SVM-45. Required pivoting. Required adjusting the SVM-45 separately for each side

In both cases, the flats were added with DMT DiaSharp fine followed by ultrafine stones. They were then stropped on a pair of kangaroo leather strops, first suede with Tormek honing paste and then smooth without any compound.

Note that Sundqvist encourages learning to do it freehand in part because "...jigs are not universally available or applicable" and also to maintain the cultural heritage (page 39).   



[1] This is not to say I'm against a concave edge for carving in all circumstances. I actually like a bit of concave to the edge of my small whittling blades. It works well for carving small-scale convex shapes.
[2] He also describes sharpening gouges and adzes with a grinding step on a wheel and honing step on flat stones, but I do not know enough about these tools to know whether this results in a flat-over-hollow grind on their curved surfaces.

CB, that's brilliant! I'll try that first. Thanks!

And, thanks for the assurance that freehanding is possible without the laser. That's my fallback for now for cases where I can't get the jigs to work. I expect it to take some practice and will choose the blades accordingly.

Rick, CB, and Rich, thank you for your suggestions. It's good to see that there are a variety of techniques that have been used with success.

I have neither a laser nor a platform, but I do want to get both of those set up some day. I was planning for a wheel-width platform, which, from Rick and Rich's comments, sounds like definitely the way to go. I've found a couple of old threads describing various laser setups, so I think I've got a good understanding of how to implement both when the time comes.

I think I'll give it a go with Rick's shimming idea first, since I have everything on hand to try it. I previously tried using feeler gauge shims in the SVM-00 when attempting to center a Mora 120 that I was trying to sharpen. I couldn't get that to work, but I think it's worth a shot with a multi-blade pocketknife both because the shim would be wider and there's a flatter surface against which to apply it. Also I would expect much smaller bevel on the pocketknife blades to be a bit more forgiving of slightly off center placement, at least in terms of being able to notice it. With the Mora's ~6mm bevels, any misalignment was quite evident.

One idea that I have for dealing with slightly rounded handles is using two cut-down soft wobble wedges, placed in opposition, as shims. That might work to cradle the handle and stay in place better. Depending on the knife, I may not be able to get it thin enough, but we'll see. I'm hoping to get some time to experiment over the weekend. I'll report back if I do.

I'm curious about how people sharpen the blades of multi-blade pocketknives on the Tormek. Specifically, I'm wondering about blades that are offset from the centerline of the handle and are also too small to be held with the SVM-45.

From what I've read here, a platform jig should handle these with aplomb. But what if, like me, you don't have one? Are there tricks for using the SVM-00 and dealing with the offset from the centerline? I haven't tried it yet, but I'm concerned about not getting even bevels on both sides. Or, do people tend to freehand these blades? Or something else?

I do plan to build a platform jig eventually, but I'm wondering whether I can satisfactorily sharpen these blades with the Tormek in the mean time.