facts and observations

[Ken S]

I have recently read a request on the forum for facts, not opinions. In general, I agree with this, as long as the facts pertain.

I do not have definitive facts to offer; however, I would offer some observations. Regarding steel grindings clogging the grinding wheel, at the ends of sharpening sessions, I regularly observe a lot of steel grindings caught by the magnet in my water trough. (The same applies with my taped on magnet on my T4.) Are there grindings which are not caught by the magnet? Perhaps, although I am convinced that the vast majority of the grindings are trapped by the magnet.

I have watched watched a couple youtubes about cleaning superabrasive wheels with chemicals when used dry. I have never noticed a problem when using an snti corrosion solution.

I have no degree in abrasive technology, just a moderate amount of sharpening experience, enough to convince me that clogged wheels are at most a minor problem. (Noted that my SJ turns black from steel deposits. I have not noticed a problem with my SG.)

Ken

[Thy Will Be Done]

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.

[Ken S]

It may surprise you to know that I actually agree with you. I certainly do not consider my observations to be conclusive proof, nor do I conclusively dismiss them. I write this in the spirit of curiosity, not criticism. There is room in the Tormek universe for both the more casual user who primarily wants sharp edges and the more scientific user who wants a deeper understanding.

I tend to fill my knowledge gap with trust. I freely admit that this is not very scientific. For example, in the debate between diamond and CBN wheels, I would refer you to the online class, "Why we like diamonds." I have a great respect for Håkan Persson, both in his knowledge background and his integrity. His work history includes working for Norton. I felt his comparison of diamond and CBN was fair and balanced. Based on what I know about him and having met and talked with him last month, I am willing to make the leap of faith in his judgement. I feel he has earned my trust.

I have that same kind of trust in a number of established companies. No one, not even Tormek, gets a free pass, although I do believe in the concept of innocence until guilt is proven. Not blind innocence, but a fair chance.

Regarding loading the grinding wheel, in a recent dialogue with support, I learned that one of the benefits of the anti corrosion concentrate with diamond wheels is to keep the grinding wheel surface clean from loading. From my limited use of diamond wheels and ACC, I have never needed to unclog my wheels.
In the spirit of fairness, when I tested CBN wheels many years ago, I had no clogging problems when using Honerite Gold as an anticorrosion solution. I do not regard either of these experiences as proof data, only as indicators. I tried to keep an open mind in both cases.

I am open to other reasonable sources. I have Vadim Kriachuk's deburring book nearby both in print and on my ipad.

Keep searching for truth; we all benefit from knowledge.

Ken

[John Hancock Sr]

One thing I have discovered over my life is that sharpening is simple yet complicated. Sometimes over complicated. If you want sharp all you need is two flat surfaces meeting at a line. However, when you throw in grit, abrasives, the behaviour of your sharpening grains, the behaviour of the material being sharpened, the geometry of the edge it can escalate quickly.

My observation is that we can overcomplicate and overthink. Sure the science is interesting and can feed into practice to improve our technique but when you look at professional sharpeners such as knife sharpening businesses or professional woodworkers they want in and out in the quickest time whilst getting good results.

Example. I bought a jointer plane Wednesday and the iron was non too smart. The edge was chipped and the bevel was not a bevel. It took me 15 minutes for a perfect edge. Ten minutes on the DC to re-establish the bevel, 30 seconds on the DF to remove the old scratches then 30 seconds on the DE to polish. Finally about 30 seconds to a minute to hone to remove the burr. It then took perfect shavings. It will take less than 5 minutes to re-sharpen and that I think is the point. I use the Tormek (and I have wanted one for a long time) to quickly re-establish sharp without any faffing around. I now have that. It took some time to establish my process and I am yet to become as confortable with the drill jig and the turning tool kit (I need more practice there) but chisels plane blades an knives are now a cinch, super easy, barely an inconvenience.

[Thy Will Be Done]

One thing I have discovered over my life is that sharpening is simple yet complicated. Sometimes over complicated. If you want sharp all you need is two flat surfaces meeting at a line. However, when you throw in grit, abrasives, the behaviour of your sharpening grains, the behaviour of the material being sharpened, the geometry of the edge it can escalate quickly.

My observation is that we can overcomplicate and overthink. Sure the science is interesting and can feed into practice to improve our technique but when you look at professional sharpeners such as knife sharpening businesses or professional woodworkers they want in and out in the quickest time whilst getting good results.

Example. I bought a jointer plane Wednesday and the iron was non too smart. The edge was chipped and the bevel was not a bevel. It took me 15 minutes for a perfect edge. Ten minutes on the DC to re-establish the bevel, 30 seconds on the DF to remove the old scratches then 30 seconds on the DE to polish. Finally about 30 seconds to a minute to hone to remove the burr. It then took perfect shavings. It will take less than 5 minutes to re-sharpen and that I think is the point. I use the Tormek (and I have wanted one for a long time) to quickly re-establish sharp without any faffing around. I now have that. It took some time to establish my process and I am yet to become as confortable with the drill jig and the turning tool kit (I need more practice there) but chisels plane blades an knives are now a cinch, super easy, barely an inconvenience.

In short, the type of minutia we are discussing only becomes relevant when you are chasing an ideal edge.  If you're happy with good enough then this is simply not relevant to your interests.  Many have very low expectations of edge retention and don't even know how the sharpening process weighs heavily in that end point.  For 99 out of 100, good enough is MORE than good enough. 

[John Hancock Sr]

In short, the type of minutia we are discussing only becomes relevant when you are chasing an ideal edge.

Pretty much. Sure edge retention - again it depends. Some blades such as scissors and to a certain extend vegetable knives require a level of tooth to function as intended. Whilst other edges such as on a scrub plane can be left at coarse and function perfectly well. (Scrub planes are all brute force and ignorance and the say in the classics.)

In the case of say paring chisels you want a nice keen edge and that warrants more attention to detail and so you would probably spend more time chasing a better edge.

So yes it all depends. I am a hobbyist but I end up sharpening for friends and family as well. But for me it is the speed and function of the system. I don't see sharpening as an end in itself. For me it is in order to get more pleasure  out of the making functional objects or producing functional tools rather than the actual process of sharpening.

Certainly, edge retention is important but if I spend an extra 15 minutes per tool only to get an extra 5 minutes of use there is not much point. So for me it is a trade off and it boils down to a time/result equation. Getting back to the original question, this is where the science cones in. It will inform my approach to sharpening to get the the most out of my sharpening system with as little expenditure as practical.

This is not to decry those for whom the experience of sharpening is an end in itself. I see the joy in refining an edge to get the lowest BESS score and the prettiest edge. However my needs are more pragmatic.

[Thy Will Be Done]

In short, the type of minutia we are discussing only becomes relevant when you are chasing an ideal edge.

Pretty much. Sure edge retention - again it depends. Some blades such as scissors and to a certain extend vegetable knives require a level of tooth to function as intended. Whilst other edges such as on a scrub plane can be left at coarse and function perfectly well. (Scrub planes are all brute force and ignorance and the say in the classics.)

In the case of say paring chisels you want a nice keen edge and that warrants more attention to detail and so you would probably spend more time chasing a better edge.

So yes it all depends. I am a hobbyist but I end up sharpening for friends and family as well. But for me it is the speed and function of the system. I don't see sharpening as an end in itself. For me it is in order to get more pleasure  out of the making functional objects or producing functional tools rather than the actual process of sharpening. It is almost amusing to see how slowly the stone can cut when it is used with light contact pressures and not resurfaced properly once you recut the surface for comparison.

Certainly, edge retention is important but if I spend an extra 15 minutes per tool only to get an extra 5 minutes of use there is not much point. So for me it is a trade off and it boils down to a time/result equation. Getting back to the original question, this is where the science cones in. It will inform my approach to sharpening to get the the most out of my sharpening system with as little expenditure as practical.

This is not to decry those for whom the experience of sharpening is an end in itself. I see the joy in refining an edge to get the lowest BESS score and the prettiest edge. However my needs are more pragmatic.

If time is an important metric then using loaded/glazed stones is never advised.  I recut my wheel far more than most people would likely that use the machine, using the truing tool, because time is extremely important to me.  Using the truing tool makes recutting the surface makes the grinding action enormously more effective at removing metal quickly and that is most of the reason for even using a grinder compared to a benchstone. 

[tgbto]

My two cents (and therefore an opinion

I think it is fine/essential/unavoidable to have opinions, based on whatever facts are available. It is both important to know opinions to be opinions, and to try to be as honest in taking into account and sharing facts as possible. Biased as a human being is, I think the best way to sift out our preconcpetions is through honest sharing and - as ThyWillBeDone put it - staggering amounts of data. This is how science worked till very recently and the advent of "alternative facts".

We also have to be careful not to be too trusting in ourselves and others. It may be tempting to consider any opinion by Wootz or Sebastian as holy scripture (I'm thinking witchcraft-like coefficients in the FVB app, AngleMaster for knives or burrless, SJ-polished edges) because *most* of what they say is rooted in facts or experience. We all have our bias, blind spots and business or personal agendas.

As far as what I pursue with my involvement in this most excellent forum, I'd frame it as the best compromise of tomato-slicing-good-enough-edge retention and total time spent maintaining said edges.

Cheers, and thanks for both your opinions and facts,

Nick.

[Ken S]

Nick,

I knew and liked Wootz from forum posts, emails and as a KG customer. I recently met Sébastien when he heroically rescued me from the Stockholm airport. The happy ending to that story was a half hour car ride together with a good opportunity for a pleasant chat. I trust both of their good intentions, while realizing that things are continually changing and evolving with a forward looking company like Tormek.

Some of the magic becomes just understanding with experience. I was curious to test Tormek's statement that the T4 could only be used freehand for knife honing. The problem was that the plastic knob of the SVM-45 knife jig wanted to occupy the same space as the support bar. I swapped out button cap screws for the jig and sleeves, ground off a miniscule part of the jig, and the problem was solved for around five dollars US. Although this worked, a regular FVB works much better. There is no magic in an FVB, just a very clever solution.

Wootz noted in one of his videos that Tormek used "Swedish leather" for the leather honing wheels. Someone at Tormek must have been paying attention. One of the displays in the new Tormek Museum describes the leather they use. It is a top drawer Swedish product. It is also described in the online class about the museum.

The most famous retained data is the closely guarded recipe for Coca cola. I certainly understand why Tormek would consider formulae for its grinding wheels as propriety information.

With some facts, observations, and opinions we move forward. Since I purchased my T7 in 2009, I have observed many innovations. I believe we will see many more, especially with knife sharpening.

Ken

[Sir Amwell]

All previous posts on this subject good and valid.
The thing is here, there's really no answers ( as yet maybe).
Sharpening stuff is one of those weird things in life.
Just when you think you've got it, it throws up something else and it escapes you again.
Real world sharpening as a business maybe: get it sharp get it out there, customer happy.
Rabbit hole chase the less Bess, facts, science, technique, angles, fractions of angles, grits, honing compounds, 0.25 microns on leather, 1 micron diamonds on rock hard felt wheels @+0.333 degrees etc.
There is science behind sharpening and there is also an art, not just technique.
Which is why it's the gift that just keeps giving, whether hobby or profession. I suppose the real innovation that Tormek offers is to provide tools to pursue that obsession.
Just some thoughts......

[Ken S]

Good comments, Sir Amwell.

When I designed the kenjig, I had three "target users" in mind: 1) Beginners who were having trouble coordinating the basic skills to get started sharpening knives. 2) Occasional sharpeners who might sharpen the home knives once a year and might have difficulty remembering all the steps involved. And 3) A busy "weekend warrior" sharpener who might have to sharpen a hundred knives in a Saturday morning.

Time and sharpening techniques have changed since then. I still think the kenjig may have some value for the first and second group. I believe the third, busier group may be better served with more recent developments. This does not discourage me. It was a valuable learning experience. I look to see the kenjig joined on "the back burner" by several things we are regularly using today.

Yes, sharpening is a gift which keeps giving.

Ken

[Ken S]

I have noticed that increasingly YouTube channels I liked for good information are becoming more like infomercials. I find this trend at least as disturbing as lack of facts, especially when the sales pitch is based on questionable information.
The best defense for this is to be prepared with good factual information.

Ken

[John Hancock Sr]

I have noticed that increasingly YouTube channels I liked for good information are becoming more like infomercials. I find this trend at least as disturbing as lack of facts, especially when the sales pitch is based on questionable information.

Yes. Particularly when they declare that they were given the product that they are demonstrating but that won't influence their opinion. As we say here in Australia "yea right!" I prefer people who say that either, they bought all of the products that they are reviewing with their own money, or as one of my favourite woodworkers said recently, "this was given to me and although I will try to be honest you will have to take into account that I am obliged though common decency  and unconscious bias to be less critical that I would otherwise be."

[Ken S]

Well stated, John.

Ken