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A few thoughts....

Observations are good, not to be discounted but they do not substantiate claims well enough to be actually considered reliable data.  Humans are always biased in what they believe they know and this is not to be underestimated. Therefore one has to design an experiment to model what they expect is happening and ideally do it in a way as to use some sort of blinding to avoid this bias.

The real question is not solved by modeling but only through testing the model to see if it holds up in the real world, otherwise that is high school science at best.  One has to go beyond this and actually test whether the model reliably demonstrates what you are expecting to be truth. 

This is not for the casual user unfortunately so what almost invariably happens is people generally take others observations as truth and run with it.  It is a much easier stance to take that you think you know what you know rather than to try and actually DISPROVE what you believe to be true.

I only knew of one person (somewhat personally via the internet) in the sharpening/knife world that did actually test whether models help up in the real world... RIP Cliff Stamp.  I mean to such a degree that I would suggest his coming birthday anniversary as National Cliff Stamp Day.  He'd get a kick out of that I'm sure as he was never one to seek out the limelight but rather knowledge.

I am still trying to come to terms with what a substantial loss his passing means to the knife/sharpening world as he put together an incredibly staggering amount of raw data that he meticulously generated.  For anyone looking into his approach then his old forum is still viewable.

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Regarding the issue of glazing and/or loading of stones/wheels.  It really has to happen if the stone cannot readily shed grit fast enough to avoid compounding both of that realities.  The problem is that as the stone begins to load/glaze that it actually becomes less likely to allow the abrasive to bite deeply enough in the tool to actually tear big pieces of abrasives away to refresh surface.

What you're left with at that point is mostly slow wearing/blunting and loading which sheds some grit but not enough to regain full cutting speed/depth. This is not an easy concept to test and is very difficult to even think you can speak reliably about individual stones/wheels because it's very dependent on force and ultimately pressure (force/surface area) applied to the surface of the stone (NOT EASY TO MEASURE) which can be estimated if you're willing to do some math.

Without even this basic data it's almost impossible to begin to entertain a discussion on these topics related to abrasives.  That's not even considering the effects of different steel types and heat treating and how that adds to the picture.

Hmmmm. I don't understand the glove concept at all. Using a Tormek to sharpen stuff is slow, relatively risk free if you have half a brain and a modicum of common sense. Things don't fly off in an uncontrolled way.
Gloves will restrict your work assessment. Unless the gloves are incredibly thin allowing for tactile assessments they will hamper your work. If they are that thin they will offer no protection from sharp edges.
To illustrate this I give the following example.
I sharpened some knives for a customer and he then complained that the knives were too sharp and he and his family cut themselves on the newly sharpened knives.
That is user error, not my fault for producing the desired result.
As a sharpener you are dealing with sharp edges. Learn to treat them in the correct way and you will not cut yourself.
Wearing gloves will only add risk in my opinion, thinking you are safe and so ignoring basic safety. Just my opinion.

In short, accidents happen if you do something long enough.  I grind on something just about every day whether my brain is fully engaged or not and it seems like it's an eventual reality at some point though I've been lucky on the Tormek.  I have however had more than a few cuts using waterstones over the years and that's all it took was a bit of fatigue setting in and focus declining.  It's not something that would really be expected to happen but mostly cheap insurance and the extra grip of the nitrile does seem to help when the blade gets wet/slippery and you're moving the blade/jig about in hand back and forth.

I've been thinking about the idea of using gloves on the Tormek recently.  I like both the added grip of nitrile coatings and the idea of cut resistance of something like an A4 ANSI rated glove just to add an extra safety measure.  I'm currently using a set of very thin nitrile gloves which are mostly just a moisture/grit barrier and quite easily tear if pulled.

Speaking of safety, there is always the old adage of not using gloves around moving machines for fear of a glove getting caught and causing injury.  I'm failing to see how that could really happen without being seriously careless but I also realize just one lapse of judgement or focus is all it takes.  What are you thoughts on this?

These are the gloves I'd like to use if I can feel confident I won't have an injury caused by wearing them....

https://www.ansell.com/us/en/products/activarmr-97-505

Hello, Merlin from the Netherlands here.

I have problems sharpening my thin 240mm Japanese knife edge trailing on the SJ-250 at 15 degrees or less with the KJ-250.

The trouble arises when the jig "hangs" on the horizontal beam weld of the Tormek machine.
The part of the Jig which hangs is the "bump" of the Jig.
I see that the older steel Jig (SVM-45) does not has this "bump", just a straight steel bar.

Does any one has a solution for this Problem ?
Or even an SVM-45 laying around to sell ?

Also is there a strategy to install the beam of the Tormek vertically to sharpening egde trailing in vertical position. ? This would solve the problem instantly

I am looking forward to learn from you people.     

I suspect this can be remedied without another jig or other mods.  Can you provide a photo of the knife clamped in the jig and described how you lift or turn the knife to follow the curve of the blade from heel to tip?

Well this is something I've actually liked the looks of for a honing wheel and with the introduction of the MB-102 coming soon I may actually begin using a honing wheel for sharpening.  My reason for avoiding this in the past was that it lacked the precision I wanted in setting the apex finish/angle AND the fact that all 'strops' --- of which the honing wheel qualifies being leather impregnated with abrasive compound --- suffer from the same problems :

- First all of the abraded steel has to go somewhere and it ends up remaining on the surface of the wheel accumulating with nowhere to go. 

- This in turn causes burnishing of the steel more than cutting and results in an apex that is heavily stressed from the very beginning

- Pressure is critical when using a strop as too much will tend to round the apex heavily and cause a significant distortion in the actual apex angle

So the way I see it, the MB-102 solves quite nicely the problem of angle control and pressure and it will be immediately added to my workshop for experimentation. 

It does nothing however for the issue of abraded steel clogging the action of the wheel.  Enter the CW-220, finally what looks like something that may be able to be properly flushed of abraded steel.

Does anybody have any experience with cleaning the surface of the wheel to remove all or most of the steel waste from the wheel?  My thought is that it would be easy to do but I hate to buy just to see.

My first thought with my T8 Black was to use it lightly, trying to "preserve the collectible value". I soon abandoned that plan. The Tormek is designed to be a working machine, not a shelf princess. My present plan is to use it as a dedicated machine set up for my woodturning tools with either my SB-250 or DF-250 and the composite honing wheel. I certainly won't be around in fifty years. I believe a reasonable program to maintain its value will be good housekeeping including regular recommended regreasing of the nylon bushings and keeping it covered. The future owner will acquire a "carefully used" machine instead of a "mint condition" machine.

While some YouTubers recommend setting up multiple Tormek's, I have never seen Tormek recommend having multiple machines. Nor have I seen Tormek recommend having multiple knife jigs. I am not saying that multiple machines or jigs will not increase efficiency for larger volume sharpening, only that this is not a strategy used by Tormek to sell more equipment. I believe that Torgny Jansson must have been a thrifty man, conscious of his customers' money. Supporting my belief is the Tormek tradition of supplying parts for very old machines. There are many machines still in regular service which are over twenty years old.

In my opinion, the new jigs and accessories represent Tormek's commitment to ongoing innovation. No one is forced to keep up with the "latest and greatest". I hope and believe that this tradition of innovation will continue.

ken

How often do they recommend regreasing the shaft on the T8?  I've been meaning to do this to mine as I've had it now for about a year and while it hasn't been run extremely high hours it has been used well.

I would be very reluctant to remove the serrations or alter the grind on a $300 knife without express (preferably written) instructions to do so from the customer. You also might want to contact the manufacturer to see if they offer factory resharpening.

Ken

Respectfully, I do all sorts of what may seem to be radical edge mods on knives far more expensive than $300.   I sometimes sell knives from my own collection and offer reprofiling service on them and fully guarantee the results as in you may send it back for a full refund if you are unhappy for any reason and I've had zero returns.  This is on knives that range anywhere from $100-$700.

I have not had a single person even complain about the results and most everyone has been overjoyed.  That's how bad factory edge work tends to be in regards to providing a functional and properly sharp edge with decent cutting ability.  As knives are delivered factory the common tendency is for a knife to be around 20 DPS, I wouldn't even grind a heavy felling axe at this geometry and I've done stuff like that at 14 DPS with zero issues.

The owner of this said he has had this knife all but forgotten about spending the last year or more in a pickup somewhere getting ignored because he hated the serrations.  I've done many deals with this customer and I am not worried about anything here, I practice the idea of simply doing right by people and I don't worry about the liability.  This is work that I am passionate about and I let that guide what I do, not a bottom line.

I've got one of these knives that was sent in by a customer to remove a chip and reprofile the edge to another geometry (lower the DPS) and was surprised to find that it had serrations on the straight part of the edge as I'd not been made aware of this. 

Upon looking further at the blade I decided that I could regrind the edge to both remove the serrations and a sizable chip on the straight edge and the customer was overjoyed about losing the serrations.  I believe I have a game-plan that will work well but I've not done something quite like this but similar. 

The edge bevel is assymetric but the primary grind is identical on both sides.  Somewhere around 5 DPS primary grind and the edge bevel is around 40 DPS inclusive if I recall and ground only on one side.  My plan was to set the edge angle to the setting to match the side of the edge which was ground but only take material from the unground side of edge until the bevel with becomes even.  Then alternate passes on both sides until I've removed the depth of the serrations.

This would be a very high angle so at the point where the serrations are virtually removed I would lower the edge angle to the proper setting to re-profile the edge to the appropriate geometry prior to sharpening.  The steel of the knife is 154CM according to the website and the owner vaguely remembers that being the case but I see no markings on the blade.

https://emersonknives.com/shop/knives/every-day-carry/cqc-8/cqc-8-flipper/

It later ocurred to me after thinking about this that I may not want to grind the serrations into the wheel as I am concerned it may gouge/chip the stone putting a very high contact pressure on the wheel as the tips of the serrations would cause the PSI to skyrocket being such a small contact area touching the stone.  I suspect there is little to worry about here but wanted to get others opinion.

I will be using the SG-250 wheel to make the modification, planned to use the Truing Tool to grade the wheel extremely coarse with a fast 30 second pass to level and condition the wheel surface. 

What are your thoughts on my approach?  How would you approach this?  Have you ever done anything like this and what might you have done differently?  Anything to add here would be of value as I'm planning to work on this blade in the next few days or so.

Hmm. The apex is basically thin as paper. This makes sense.

It's actually much thinner than paper at the apex, strength of steel is nonlinearly related to thickness so that small increases in thickness can have very large increases in strength.  There would be very little strength at the actual apex because of this and it is generally easy to deform and/or fracture as you see quickly misusing almost any knife which is not absurdly overbuilt as to make it more of a knife-like-object... silly things like cold-chisel edge geometry that you find on many 'tactical' knives.

I have bought an aftermarket F360 (JIS600) SiC stone. I trued it with the diamond no problem, but trying to put the dressing stone onto it resulted in a desaster. The dressing stone was grooved immediately, being of the same nature (the wiser gives way...)

This process I saw named here in this context with the term "glazing", and it sure looks glassy, but I do not know what it means technically in conjunction with a grinding stone.

I have a similar wheel on the (fast) bench grinder (green SiC) which I can only true with a tetra-boron grader stick.

The prior wheel btw is medium hard bond (grade "J") and reacts to pressure, so you can adjust how much it "grips". The SB wheel appears to have that feeling too. Maybe this is a peculiarity of the abrasive in conjunction with fairly weak bonding. That said, the SB is much coarser too.

The re-seller of those (he has them custom made from a huge manufacturer of abrasives in Germany) is a professional sharpener and he had them made because of the very dilemma you outlined above, namely having only coarse grits and very fine grits available and nothing inbetween.

Said sharpener told me that he never uses the grader, because it does not really change the grit (how could it?) but shave off the peaks. The inherent danger is said to be two-fold:

• the wheel can become untrued by heavy grading
• spots can brake free that release fresh sharp material thus making the perceived roughness uneven across the circumference

The #800 Matsunaga stone you mention has been tested by Wootz (linked to by my reference further above) and was found useful only for carbon steel.
It does seemingly little on soft steels. Just to keep in mind.

I was intrigued to get a similar stone in white alumina from the same source (and they are reasonable...)
but the burnishing bit you mention irritates me. I do not know technically what this means.
All I know is every mason I know has one of those (albeit on a fast bench grinder) and every manufacturer claimes "a cooler grind", but I have never read a first-hand explanation for that, particularly in context with wet grinding.

If what you say (that burnishing weakens the steel) is applicable here, than this is an argument that has to be taken serious.

If you've ever bent a metal coat hanger back and forth until it breaks then you've demonstrated what is at work with burnishing.  You're basically flexing the metal back and forth at the apex and every bend further weakens the steel and the end result is fracture of the metal. 

Anytime you are not actually cutting the steel with abrasive that is cutting then you are merely pushing the steel, this is the basic mechanism of a sharpening steel to align the apex as it rolls, dents, etc.  It can help things in the short term but in the long term it degrades edge retention.

If you click at that link, it will tell you the time in your timezone.

I see it there now, thank you for pointing me straight here.

And what are the facts?

No, I meant, what are your facts? Is your single personal experience opinion supported by scientific data or by experince of multiple experienced users?
I hear what you are saying, and do not have any reason not to trust you.
I'm just asking for the many others, supporting your concern.

Both scientific fact and experience of users that I trust who have done a lot of research themselves but I want to be clear that this is not Tormek specific and speaking of abrasives in general.  It may be just a small problem and I may begin to experiment myself compared to 800 grit JIS King wheel I have not used yet but the reality is most end users understand little of abrasives technology and/or metallurgy and it requires knowledge of both in order to make an informed observation/judgement in the matter.  It may be a complete non-issue but in general consumers should take information provided by manufacturer literature with a grain of salt as it can easily be full of truths that are not quite true.

That is my concern about the stone grader is I'm still not convinced it isn't doing just that, glazing the stone.

That is certainly a valid concern.
It should be seen in context with the real live experince of a significant numer of SG-250 users.
Please be so kind to provide facts for the Tormek SG-250.

And what are the facts?  That people use it and claim it's just fine?  I would not call that a fact but more of an subjective opinion on the matter.  I would suggest that if anybody has to provide facts for the SG-250 it would be Tormek who in fact has the burden of proof on that issue to actually convince it's customer base that it's just as good as a dedicated medium grit wheel.  I've seen no such supporting data or studies to even begin to have an educated conversation on the matter so what we're left with is entirely internet conjecture and anecdotal reports suggestive of performance.

Even if the stone cuts in a way that leaves a finish that is very close to 1000 grit or whatever equivalent, the difference would be completely undetectable to a casual user who would almost certainly not even be aware of the differences between a strong cutting abrasive and one that strongly burnishes.  I will admit that I have not experimented much with this but the fact that you take a very coarse abrasive and make it cut like a medium abrasive is almost by definition what happens when abrasives get glazed over.  If I simply let my SG-250 wear on a D2 blade rapidly I can see and feel the aggression lost.

I just did one yesterday and it sure felt and looked like the stone was burnishing a fair amount so I'll just recut the surface and renew it.  It strikes me as rather odd that Tormek offers three grades of Diamond wheels and only a very coarse or very fine option for ceramic or silicon carbide wheels respectively.  I don't see anybody here seriously suggesting taking a fine diamond plate to their diamond wheels in order to have it cut finer and finish cleaner.  That would just be ridiculous but it does get recommended in other places often enough at various forums.  That is the same line of thinking...

Would that be AM or PM?

The grey aluminuium oxide wheels have less friable grains and thus wear less but create more heat and friction.

Is this relevant in a slow running wet grinder? I know this to be the reason for all masons, who sharpen their chisels on a fast running bench grinder, to choose a white alumina stone...

It wouldn't be a problem with friction generating heat but it would still have the detriment of burnishing the steel (ie. pushing it around) rather than cutting it cleanly.  This will only serve to weaken the steel at the apex and slightly behind it so it's never really a good thing to have a glazed or worn abrasive.  That is my concern about the stone grader is I'm still not convinced it isn't doing just that, glazing the stone.  We have companies investing large amounts of research into making abrasives that continue to fracture and renew themselves to present aggressive cutting particles.  This whole concept just seems to fly in the face of what I think I know to be true.