Leatherman multi-tool sharpening

[Sharpco]

I can sharpen the Victorinox multi-tool with the SVM-45. However, the Leatherman multi-tool does not fit correctly on the SVM-45. It is not fixed to the jig or the angles of both sides are not the same.

I tried it with SVM-00 but it did not fit Wave or bigger models.

[Jan]

Blades of most pocket knives have flat ricasso. Mounting the knife jig clamp here helps to stabilize the blade in the jig.

I thing Leatherman Wave multi-tool has small ricasso also.

Jan

[RickKrung]

Dunno.  Maybe it was due to not knowing any better, but I sharpened my two Leatherman Waves using the SVM-45.  These were some of the first knives I sharpened and I'd probably to a better job now.  I messed the tip up on one and the bevel width is wider towards the tip.  Given the reading I've done since, I'm sure that was due to poor technique. 

I'm not sure if it is a ricasso, but the blade has a narrow unbeveled section (~4.5mm wide x ~52mm long and 2.5mm thick) along the back edge of the blade. 

As I have mentioned in a couple of my posts, part of my motivation for getting a Tormek was realizing that the guy that I had taken my Wave to for sharpening several times was doing it on a Tormek using some sort of jig.

Rick

[Ken S]

I have the impression that the SVM-00 small blade tool is primarily designed for wood handled carving tools. It is a nice tool, one a well equipped Tormek sharpener should have. I incorporated it into my kenjig program to maintain a standard 139mm Projection with all common kitchen knives. It works, however, I find it "fiddly"(borrowing a term from Alan Holtham) with paring knives. I have since switched to using a second kenjig calibrated to a Projection of 125mm with the SVM-45 without the SVM-00.

This is not a fault of the SVM-00. Most tools have an optimum range where they work best and an extended range where they are functional. Tormek could easily make half a dozen or more sizes of knife jigs. Wootz has done that by modifying his jigs. A number of forum members and high end professional sharpeners would appreciate that versatility. However, due to low volume, the program would probably result in a loss, not wise for any business. This is an instance when I wish I had machinist skills.

Ken

[Jan]

Ricasso is an unsharpened length of blade. I sometimes mount the clamp here to stabilize the blade in the jig, especially when the blade tappers towards the edge.

Jan

[Sharpco]

Actually, my multi-tool is TTi. It is almost the same product as Wave. But if you look closely, the grinding is a bit different. The flat side is a little narrower. So it isn't fixed properly on the jig.

I have two SVM-45, but all have the same problem. I think the thumb hole is the cause.

[RickKrung]

Actually, my multi-tool is TTi. It is almost the same product as Wave. But if you look closely, the grinding is a bit different. The flat side is a little narrower. So it isn't fixed properly on the jig.

I have two SVM-45, but all have the same problem. I think the thumb hole is the cause.

Sharpco,

"the flat side" of what?  The jig or your knife blade?  If referring to the jig, I would call the flat side the "fixed" jaw and the side with the thumb screw the "movable" jaw.  The movable jaw is recessed about 0.5mm deep to about 15mm in from the leading edge.  At first glance, give that the unsharpened spine on my knife blade is about 2.4mm thick, I thought that would cause and offset of about 0.7mm from the actual centerlined of the jig and I thought that might lead to a slight difference in the width of the two beveled sides. 

But, if you look closely at the parting line (of the mold) along the SVM-45 shaft, you can see there it shifts a bit from the centerline of the shaft to the flat blade of the fixed jaw.  That shift results in an offset of the flat part of the fixed jaw of about 1mm.  For a blade like mine, that offset puts the centerline of my blade about 0.3mm off from the centerline of the jig (shaft).  I'm sure this is something that was carefully engineered by Tormek to try to accommodate the wide range of knife thicknesses the jig will see. If that is enough to cause the widths of the grind on each side to be substantially different, I'd have to have some with a lot more experience than me show how much difference it makes.

Maybe Jan, with his trig. and geometry could demonstrate it graphically. 

If I misinterpreted what you mean by the flat side, I've just gone on a interesting (at least to me) goose chase.  If you mean your blade has a flat side, without thinking about it much, I would expect difference in the grind width. 

Rick

[Sharpco]

Actually, my multi-tool is TTi. It is almost the same product as Wave. But if you look closely, the grinding is a bit different. The flat side is a little narrower. So it isn't fixed properly on the jig.

I have two SVM-45, but all have the same problem. I think the thumb hole is the cause.

Sharpco,

"the flat side" of what?  The jig or your knife blade?  If referring to the jig, I would call the flat side the "fixed" jaw and the side with the thumb screw the "movable" jaw.  The movable jaw is recessed about 0.5mm deep to about 15mm in from the leading edge.  At first glance, give that the unsharpened spine on my knife blade is about 2.4mm thick, I thought that would cause and offset of about 0.7mm from the actual centerlined of the jig and I thought that might lead to a slight difference in the width of the two beveled sides. 

But, if you look closely at the parting line (of the mold) along the SVM-45 shaft, you can see there it shifts a bit from the centerline of the shaft to the flat blade of the fixed jaw.  That shift results in an offset of the flat part of the fixed jaw of about 1mm.  For a blade like mine, that offset puts the centerline of my blade about 0.3mm off from the centerline of the jig (shaft).  I'm sure this is something that was carefully engineered by Tormek to try to accommodate the wide range of knife thicknesses the jig will see. If that is enough to cause the widths of the grind on each side to be substantially different, I'd have to have some with a lot more experience than me show how much difference it makes.

Maybe Jan, with his trig. and geometry could demonstrate it graphically. 

If I misinterpreted what you mean by the flat side, I've just gone on a interesting (at least to me) goose chase.  If you mean your blade has a flat side, without thinking about it much, I would expect difference in the grind width. 

Rick

It means flat part of the blade(written S30V).

I can choose to turn the knob harder for a more firm fixation. But I have experienced screwing the knob (plastic) too hard to break the thread. So I am careful.

[cbwx34]

Sharpco,

If possible, a picture or two of the knife, and how it sets up in the jig, might help figure this out.  Clamping "harder" is usually not a solution... but adding padding of some sort might help, like thin strips of rubber or something.

[Sharpco]

Sharpco,

If possible, a picture or two of the knife, and how it sets up in the jig, might help figure this out.  Clamping "harder" is usually not a solution... but adding padding of some sort might help, like thin strips of rubber or something.

You're right.

I tried applying duck tape to the blade and clamp it, but nothing is changed.

[cbwx34]

It depends on the tape, but duct tape can be rather slick/smooth on the outside, and not hold well.

You might look at wootz's "Knife Jig Solution"... see if there's a tip in there that will correct the asymmetry.  (I think this is what Rick is referring to).

But realistically, that knife may be too small to adequately sharpen with that jig... you probably can do it... but may not be the best way.  Might be worth looking into Herman Trivilino's "Homemade Knife Rest"... or just freehand sharpening it. 

[RickKrung]

You might look at wootz's "Knife Jig Solution"... see if there's a tip in there that will correct the asymmetry.  (I think this is what Rick is referring to).

Asymmetry is what I was talking about and if I'd seen Wootz's post, I wouldn't have bothered, just referred to it.  I haven't read the post yet (entertaining granddaughter this AM), but I will with great interest.  Using a set of feeler guages is brilliant; very cheap and readily available.  My point, in part at least for the blade under discussion, was that the blade offset was slight enough as to not be the source of the asymmetry in the bevel width difference.  Perhaps after reading the post, I'll think differently.

Rick

[RickKrung]

You might look at wootz's "Knife Jig Solution"... see if there's a tip in there that will correct the asymmetry.  (I think this is what Rick is referring to).

"Your miles may vary"

Very interesting and informative thread.  Anyone interested in keeping the bevel width on each side of the blade as uniform as possible should study it (not just read it).  Interestingly, at least to me, I noted that Wootz refers to the offset from centerline as being 1.25mm.  Being curious, I disassembled my SVM-45 and started making measurements.  I tried several ways of making the measurements, mostly indirect.  But, finally, I realized I could make just three very direct measurements, using a very accurate and precise micrometer to come up with the numbers to compute the offset.  I worked in inch measurements and converted to mm. 

Measurement 1: Thickness of the Flat.

The fixed jaw on my SVM-45 is very flat and uniform near the transition from the shaft to the flat, offering two opportunities for good measurements.  I measured the thickness of the flat, from the back to the face (towards centerline).  0.352" (first photo).

Measurement 2: Thickness from the back Flat to the Top of the Shaft.
0.629". (second photo).

Third Measurement: Diameter of the Shaft.
0.471".  Important dimension is the radius, not the diameter, so  0.471 / 2 = 0.2355" (third photo)

Calculation:
Distance from the top of the shaft to the front face of the flat.
0.629 - 0.352 = 0.277"

Offset from centerline:  Difference between distance from the top of the shaft to the flat and the radius of the shaft:

0.277" - 0.2355 = 0.0415"  This converts to 1.054mm.  This is the offset from centerline, as measured on my very recently purchased SVM-45. It occurs to me that 1) these are castings (albeit precision ) and they vary, 2)  production process, including patterns change, so through time, you cannot rely on one person's measurement of one jig.

The take-away for me is that, anyone who is going to take things to this level of detail/precision should probably measure their own jigs, so as to determine for themselves, exactly what the offset from centerline they are dealing with.  It is very easy to do if you have a caliper or micrometer, and I would guess that anyone attempting to achieve the symmetry discussed would have these tools. 

It goes for different jigs as well.  I measured my SVM-140 and found the offset to be 1.5mm. 

Rick

[wootz]

By gosh, Tormek has changed the offset in their new SVM-45 knife jig which is thinner than the previous one!
Our 1.25mm offset is for the previous version of this jig.

Rick, thank you so much
Your measurement of the SVM-140 offset of 1.5mm is equally appreciated.

So now what conclusion comes?
The old SVM-45 knife jig gave ideally symmetric bevels on blades 2.5mm thick at the spine;
while the new SVM-45 knife jig gives ideally symmetric bevels on blades 2.2mm thick at the spine.

Let me just remind that simpler than shims method is putting on the spine at the clamping site layers of cloth tape to match the ideal thickness. After a few trials, I found that the Norton Bear 50mm cloth tape is best for that (and also protects the blade from scratches left by the jig jaws).

I will update my old thread with your new findings.

[RickKrung]

Your measurement of the SVM-140 offset of 1.5mm is equally appreciated.

"Trust, but verify"

Rick