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Marius Hornberger has an interesting YouTube channel with woodworking and shop videos that are often notable for his workshop ingenuity.  He has just done a video about the first phase of making a workstation for his T8.  It is really just a purpose-built cabinet, but it has some interesting features:

https://www.youtube.com/watch?v=R-CvF8LBbao

Gord

I came across a YouTube channel ("Cutting Tool Engineering") about metal cutting, with a number of videos on types of grinding wheels, abrasives, steels, etc.  It has several videos in a series called "The Grinding Doc".  These are buried within a hundred or so more specialized videos on machining, but I have found several of the more basic grinding videos to be informative.  Here is the link:

https://www.youtube.com/user/CTEplus/videos

Gord

I bought, and have now tried, the new knife jig for Tormek (or similar machines) made by "Hewn & Hone, a sharpening supply outfit founded by UK blacksmith Nic Westermann.  There are instructional videos on the Hewn & Hone website. Some of my pictures and a sketch are attached below.
 
Apologies for this book-length post, it is half the length of my original ramblings and still seems to go on.  Conclusion: The jig is quite specialized but excellent at what it was designed to do.

The jig is optimized for grinding scandi bevels on "sloyd" blades (relatively small wood carving knives).   It sells for £84, or about US$105.

Westermann is an advocate of the traditional approach of starting with a hollow grind for the shaping of the scandi (wide) bevels on sloyd blades.  The Tormek and similar machines can be perfect for this as long as the grind is repeatable.  Otherwise, too much time and steel are wasted reshaping the wide bevels on each trip to the wheel.  The objective of the jig is to put (as close as possible to) exactly the same bevels on a blade each time it goes on the wheel.

Once the bevels are hollow ground, a narrow apex bevel is sharpened on a flat surface (stone, diamond plate, abrasive film, etc.).  The flat surface contacts only the outside edges of the hollow grind, so the same angle of the scandi grind is maintained at the apex bevel.  You can sharpen the narrow apex bevel in this quick manner multiple times before having to go back to the wheel to redo the whole scandi grind.  (There is a discussion of this by me and a sketch by CB in a thread on scandi grinds: https://forum.tormek.com/index.php?topic=3680.msg25257#msg25257)

Interestingly, Westermann recommends using a dry CBN wheel on the Tormek (or similar machine) with this jig.  CBN because it is fast and the wheel stays a constant diameter between grinds; dry because scandi carving blades are often (by preference) in wooden handles that are vulnerable to the water involved in wet grinding.   I used the SG-250 wet and kept my handle dry with tape, but I can see the place for a dry CBN wheel on the Tormek in this application, especially because its constant diameter enhances the repeatability that the jig is aiming for.

The jig:   The jig is very accurately machined, albeit in a starkly functional way with no attempt to be pretty.  The blade is clamped in the jig by tightening two countersunk machine screws with an Allen key.  Having two screws spreads out the stress on the jaws and allows for clamping a blade with tapered thickness.  More on this below.
 
The three main design differences that I see between this jig and the Tormek knife jigs (SVM-45 and SVM-140) are that:

(1) the Tormek jigs hold the blade by having a moveable jaw tighten against a fixed jaw, whereas the Hewn & Hone jig has two fixed but (slightly) flexible jaws that are pulled together to clamp the blade;

(2) the Hewn & Hone jig is optimized for scandi grinds, such that the thin jaws of the jig—much thinner than those of the Tormek jigs—can grasp the small blades very close to the grind and still clear the wheel; and

(3) the Hewn & Hone jig is optimized to hold a relatively small blade in a set position each time the blade is mounted in the jig, so that the grind is accurately repeatable in subsequent bevel shapings on the wheel.

1. Self-centering jaws:  The design of the jaws results in a "self-centering" grip of the blade, whereas the Tormek SVM-45 and 140 jigs do not.  For knives that are thicker or thinner than ~2mm thick where they are clamped, the Tormek knife jigs hold the blade at an offset from the centre line of the shaft of the jig.  If not somehow compensated for (by shimming or thinning the fixed jaw of the jig, as required) this results in the grinding of unequal bevel angles.

Now, one feature of the particular self-centering design of the Hewn & Hone jig—basically a pair of jaws machined into a solid block of steel—is that it has a much more limited range of opening and closing than the Tormek knife jigs.  To move the jaws, you have to flex two sections of solid steel, so the gap between the jaws can only be varied by a relatively small amount: the range is from a minimum of 2mm to a maximum of 3.3mm.  With the (recommended) use of a protective gasket (such as a piece of paper or cardboard) between the jig and the blade, I found that the effective range of blade spine thicknesses that I could fit securely in the jig was about 1.5mm-3mm.

2. Thin jaws:  I have found the SVM-45 and 140 Tormek jigs to be too bulky to do a scandi grind on a small blade without the jig hitting the wheel.  I don't consider this to be a fault in the Tormek jigs—they are just designed to accommodate wider (and a wider range of) blades than this specialized jig.   The Hewn & Hone jig has very finely machined, thin jaws (see pic).  They have been machined to a fine point so that the jig clears the wheel even when the bevel comes within a few millimetres of the point where the jig is holding the blade.  (Note that, even with this thin jig, you have to be alert to avoid grinding the jig itself.)  Because the jig is machined out of steel, the jaws are strong even though they are thin.

3. Fixed angle mounting: The third difference in the design of this jig is that it is optimized to hold a typical sloyd blade, which is somewhat triangular: wider at the handle and tapered to a point.  And unlike the Tormek jigs, this jig is machined with a groove that will hold the blade at the same fixed orientation to the wheel each time it is mounted in the jig (see attached sketch).  This fixed orientation will tend to be approximately perpendicular to the wheel, which is generally what you want, but the more important thing is that it will result in grinding the same bevel each time the blade is mounted in the jig.

This should make the grind closely repeatable for subsequent shapings of the same blade.  You can "override" this feature by not pushing the blade to the angled back of the mounting slot, but then you are on your own for repeatability.

Trial: Once I had fitted a few blades into the jig I found it quite intuitive. It required considerably more attention than I give to the Tormek knife jigs.  The two machine screws should be tightened, back and forth, a bit at a time, and the same in reverse to unmount the blade.  I found this to require some dexterity, but I got used to it, and it works.  Once a blade is in, it is in solidly.
 
So, on the one hand the task of mounting is somewhat more fiddley, but on the other hand the task of getting it mounted in the same place the next time is much easier.  The latter is more important to me, so I can live with former.

To try it out on my T8, I mounted a new Frost/Mora 106 (see pic—flat ground scandi sloyd) in the jig and ground it on the SG-250 coarse, horizontal position.  The bevels came out as close to equal as I could measure. 

Then I unmounted the blade, Sharpied both of the new bevels, remounted it in the jig and put it back on the wheel.  It was pretty darn close to hitting at the same place all along both bevels: the marker was gone in one pass on each side.  So, on this blade the repeatability of the grind seemed to be reliable.

I tried this jig out on one of my kitchen knives.  It worked, but I don't think that is what this jig was designed for, and I would recommend caution using it on knives with wide blades.  A self-centering jig doesn't produce even bevels unless the blade is mounted in line with the shaft, and the narrow bearing surface with which this jig grips the blade creates the potential for missing, or failing to keep, that inline clamping position on a wide kitchen blade.

I also tried this jig on a small non-scandi blade: a medium-sized pocket knife blade.  It felt secure and more easily aligned with the shaft than with the Tormek small knife jig (SVM-00). 

I tried it on a tiny pocket knife blade, but the blade was too small: the jig hit the wheel.  So, this jig does not replace the Tormek small knife jig.

Side note for pivoters: Westermann advocates lifting, not pivoting, to keep the angle consistent along the curved section of a blade.  The stop collar of the jig is wide, to keep the jig consistently perpendicular to the wheel.  I am experimenting with pivoting the Tormek knife jigs on the T8, and will make one of my triangular collars for the narrower shaft of this new jig just to try it, but I prefer the simplicity of only lifting, so this jig works for me as-is.

In summary, this is a rather specialized jig, but in my initial testing I found it excellent for the type of blade it was designed for.  I have found hand grinding scandi bevels on flat surfaces to be tedious and sometimes inexact, and my impression is that a lot of carvers feel the same way.  This jig opens up a whole new way—faster and more exact—of coming at that task.

Gord

The topic of the "small platform jig" has come up again in a recent post so, for posterity, I have gathered the links to the previous discussions of (homemade) small platform jigs, and set out the details of the one I have made.

None of this discussion is original to me: all of the ideas came from the following threads, which I gather here for those who want to do the background research or just to have the main threads (at least, the ones I could find) gathered in one place:

•   Ionut's "Small knife blade rest – improvisation" thread
https://forum.tormek.com/index.php?topic=1191.msg3308#msg3308
•   Herman's "Homemade knife rest" thread:
https://forum.tormek.com/index.php?topic=1592
•   Herman's "Re: Ionut's small knife jig" thread:
https://forum.tormek.com/index.php?topic=1560.0
•   CB's thread "The one change you should make to the Tormek":
https://forum.tormek.com/index.php?topic=3459.0
•   CB's thread "Finally made a homemade knife rest":
https://forum.tormek.com/index.php?topic=3610.msg23411#msg23411
•   Y-Not's thread: "The learning curve":
https://forum.tormek.com/index.php?topic=3586.0
•      Elden's thread: "Self-contained jig based on Herman-Ionut jig"
https://forum.tormek.com/index.php?topic=1605.msg6897#msg6897

As discussed in these threads, there are many potential uses for a small platform jig.  Also, it can save some calculations and re-positioning when using the Anglemaster for the sharpening of blades that are tapered from the spine to the edge (this is discussed in the threads).

Here are the details of the small platform jig that I made; there are some pictures below.

I made the plate out of ¼" aluminium stock, instead of 1/8", for (1) stiffness; (2) extra height above the scissors jig platform for handle clearance; and (3) countersinking the attaching screws flush with the plate.

I used the scissors platform as the method of attaching the platform to the USB for the reasons discussed in the above-cited threads.  (Note that the adaptation of the scissors platform does not interfere at all with the use of the platform for its intended purpose with the scissors jig: when the small platform is removed, the scissors platform just ends up with two innocuous holes in it.) 

If I had a T2 jig, I might have tried using it as CB did: it looks like it would be at least as effective and maybe less bulky than the scissors jig platform, though perhaps providing less support for the plate.  The challenge of adding support for the plate (with the tools I have) also steered me away from kwakster's otherwise very elegant use of a bare Torlock collar with a plate attached and undergirded (see "The one change..." thread).

I located the small platform at the righthand edge of the scissors platform because that was what Herman and others did; this was pure imitation, it might be that the location of the plate on the scissors platform doesn't make any difference.

2" (matching the width of the wheels) is the maximum width of a small platform like this, so that blades can slide along the platform with their bolsters or handles right up to the edge of the wheel, and thus be sharpened along their whole length. 

The 2" plate for my small platform turned out to be 5 3/8" long.  I ground the angle of the leading edge at 15 degrees so that the thin edge of the plate would be close to the wheel for the most acute angles I was likely to use it for—about 15-20 degrees.  When I raise the USB for a more obtuse angle, the front edge stays tight to the wheel, so it still works in the 20-40 degree range.  (If I had ground the platform edge for a more obtuse angle, the edge of the plate would be rise above the wheel when the platform was lowered for more acute angles.) 

I drilled the holes in the piece of aluminium bar, then used them to locate the holes in the scissors platform.  It would have been cleaner to then thread the holes in the scissors platform, but I wanted a tool-less connection, so I drilled through-holes in the scissors platform and used wingnuts to fasten the machine screws underneath the scissors jig platform.  The tapered stainless steel machine screw heads grab the aluminium plate themselves without needing to be held, so attachment and removal of the plate just involves spinning the wingnuts—no tools needed.

Based on earlier comments, I tried various non-slip surfaces on the platform to minimize blade scratching from the platform surface, but I find (as Rick and others have noted) that the scratching isn't from the platform surface itself, it's from the grit getting on the platform (or on whatever it is surfaced with).  Regular wiping helps.  A good surface covering is felt, because the grit seems to disappear into it, but the softer the platform surface, the less precise the work.  I am now trying a wide piece of Velcro as the platform surface, because the grit can fall below the surface that is contacted by the blade, but there is still some stiffness to support the blade.

It might be that now that we have the small knife jig, one of the main drivers for the platform jig has gone, or at least diminished.  However, I quite agree with Ken's view that there are many other potential uses for a small platform jig, including the ability to sharpen just about anything on the platform, with flexibility that the Tormek tool rest (SVD-110) does not provide.

Gord

Today this YouTube video came up on my feed, a fellow with a T8 describing his use, as a (Swedish) homesteader, of the machine.  He sharpens a Marttinni filleting knife with the SVM-140 (long knife jig) and then fillets a bunch of fish.  (Incidentally, he is a lifter, not a pivoter.)

https://www.youtube.com/watch?v=ODXcuX9DTqI

Gord

While I am not convinced that I am good enough on the Tormek yet to improve my results by pivoting (rather than just lifting), I am impressed by the enthusiasm of those more experienced members who like to pivot.  I have made the "four stop collars" pivoting mechanism and quite like it.  I have one of Rick's collar-and-pin mechanisms on order and comments like Wootz's tell me it will be brilliant.  But a postal strike in Canada has delayed Rick's jig getting to me, so I made one of my own that seems to do the job very well.  You might call it a wedge collar.

The governing factor in this design was simplicity in fabrication: I am no machinist and I wanted something that could be made by anyone with a hack saw and file (and drill press, for the holes).  Also, I wanted to design something that someone could make out of plastic, either by shaping it or by using a 3D printer, and so it had to have more reinforcing bulk than Rick's pin collar.

I find this wedge collar very easy to use.  The fingers (of the hand you are using to hold the knife jig) can slide up comfortably behind the wedge; you can leave off the disc supplied with the SVM-45 and SVM-140.  The pivoting is very fluid, and the range of pivoting is more than sufficient for the knives I have tried it on.

As I said, I wanted this to be easy to make.  It is made from a 2" length of a 1" square bar of aluminium, which I drilled and then cut to a triangular shape. 

Stainless steel would be better than aluminium: less friction and wear, but I haven't noticed the friction from the aluminum, and machining stainless steel would require tools I don't have.  A block of UHMW plastic should work, and might be nicely slippery on the USB.  I don't know much about 3D printing, but the wedge seems like a simple project, perhaps with the holes being done after.  Of course, wood would be easiest, but there are drawbacks when wood is used around water.

Gord