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Dan,

that bench grinder hack I was thinking of too. In this case you don´t have any obstruction.
This device does not work well in its native mode, wet grinding, since it grinds away from you, and you cannot easily work from the other side, as on the Tormek. But it appears perfect for honing purposes as shown. Congrats.

Maybe the obstruction just occurs on a T-3, which I have.
I recently had a knife in the new symmetric knife jig, and a projection of some 145mm.
IIRC the knife´s handle or my hands or something bulky interfered with the USB´s support rods.
As soon as you raise the USB bar (by using the vertical support of the FVB), the rods disappear downwards and your action range is cleared again.

It wasn´t a particularly long knife either, just a 20cm kitchen knife or shorter.
The FVB rotates the contact point of the knife upwards, which makes for a much more natural working position too.

You have to remove the grinding wheel, or it will be in the way.

If one wished, a cone like that could be easily done with a 3D-printer nowadays, but this would again limit you to the angle it was designed for.

As I said.

I did some freehanding in early days according to the method shown by Tormek. You can choose your working position to an extent. My results were inferior.

After studying Wootz´works, I am convinced that you need to be precise with deburring too, because either your angle is too low, or too high (either useless or ruining your edge) or just right. It is too easy to have the wheel catch the blade and then be off the right spot.

That settled, I found that using the USB on the horizontal position for honing does not work in many cases.
The position you need is obstructed by some machine component.

Using a FVB breaks you free from that limit. I knitted my own which works a treat, but in the lights of above offers, it is not really worth. The main cost factor is the XB-100. Note that having a rod with a standard metric screw is not of much use, but again you don´t need it since you use the precise screw on your USB.

The knife I finally bought (see originial post) has a 50/50 grind @ 15dps - despite the typical geometry a knife of that provenience would have. This makes things easier.

Thinking about this, we are practically speaking about a micro-bevel. Kippington explains in post#25 that a knife that slim (look at the picture...) has such a thin cutting edge (initially at least) that you cannot practically grind asymmetrically. A blunt blade yes, but not such a thin blade. (Note that he kind of contradicts himself at this point...)

A funny aside story to do with that knife:

I know some knives for the Western market are shipped less than perfectly sharp. When I was at the store I raked my thumb over the cutting edge as I usually would. I uttered that it was in need of some touch-up.
I was told by the store owner that this method would not apply, I think her argument was that "Japanese knifes are different".
So when the specimen was subjected to the tomato test, I thought there was leeway for improvement - Japanese or not.
I gave it a few strokes with my J1000 stone from Dictum and honed it with the felt wheel. Needless to say that it cuts better now and that the thumb test was not dumb after all.

Wolfknives (Feines Werkzeug) in Germany. Unbeatable Price.

Hi Jim,

since nobody is replying...
look at the site of (sadly defunct) forum Member Wootz: http://www.knifegrinders.com.au/

I had those very questions answered by reading his deburring booklet (pdf or whatever).
This costs a few bucks but is reasonable. He has a video there that may already answer your questions.

Another part of the equation is maintaining the correct angles throughout. On the Tormek, this boils down to one single adjustment: the universal bar´s (USB) distance to the grinding wheel. This is most easily calculated by one of the programs that are available for free on this forum.

It lead me to the right steps, and now I have knifes with great sharpness.
Far beyond perfection perhaps, but that is not the objective.

have fun,

-Helmut

[Juranitch]

I may have mixed up your two topics.

Not to worry.

are you talking about your Japanese knife or more "garden variety" western knives?

Both. As long as a knife has an edge, its grind will yield an angle.
That means for Japanese knifes, both sides may not have an equal angle.

Some Japanese sharpeners say, they don´t care about angles, they go by feeling. However, the result will be an angle - and according to Vadim´s protocol, you better take that one into account when honing.

I have two ceramic honing rods. Both came with angular cones built into the handles.

Very advanced! They have learned. But agin, what angle?

I find the steel file teeth too coarse for my liking.

And right so. One sorce (which I don´t find on the quick) tells us that a honing rod should never remove metal. There are some rods that have a very silky smooth texture, a hint of nothing, to even blank ones. Their sole purpose is to re-erect the cutting edge that tends to get bent to the side due to its fragility.

I think the average non geeky home cook would be better served with a flat, leather covered wood strop with PA-70 honing compound. The flat surface  seems easier to control.

I have a cheap ceramic rod (and for hard steels you probably need something harder than the blade), but I also use a strop. You may of course use any compound except maybe Chromium green - which is too fine. But PA-70 is there, fine.

We may ask ourselves, is this rigmarole necessary? If we agree that after sharpening, honing needs to be done at an angle precisely related to the sharpening angle, then, why should repeated honing with either honing rod or strop not  happen at the same angle? If this did not matter, then those measures could be tossed. But it does matter. Juranitch claims several times the service life.

And that takes into account that this on-site honing is not performed with a precision anywhere near what a rigid set-up on the grinder would allow for. Another point for the rod not being abrasive...

That is interesting.
I wanted to quantify the geometry of my knife, but it is very hard with me old eyes despite all distorting magnifying glasses.

The blade is very thin and asymmetric, but somewhat rounded with no sharp transitions between the bevels, so it is not easy to put a finger on things. It is asymmetric, that is for certain.

I notice drawings showing one bevel being convex. With a little practice, the KJ-45 should be ideal for this work

Actually, both bevels are convex, just not as much. For right handed knifes the right side is more convex to aid food release. Unfortunately this creates more pressure there that by tendency steers the knife left. Hence the prominent grind on the left side for compensation.
That is what is reported anyways.

Ken,
While I agree with you on discipline, I cannot see the average house wife or hobby cook having a Mercedes standing in the kitchen.

This is something for geeks. Even I would find this a total overkill.

Yet a honing steel fits every drawer. In fact, most people probably have one lying there idle...

As I said: sharpening with a wink...

[John Juranitch]

Now this subject is not entirely sharpening related, but it is knife related. As such it would fit into a forum like the sadly defunct kitchen knife forum, but due to the technical relation it also fits perfectly into the league of spreadsheets available here vor diverse sharpening calculations.
This may be a nice-to-have addition to your box of tricks.

I recently read the sharpening book by John Juranitch, The Razor Edge Book Of Sharpening. On page 43f. he speaks about steeling your edge. He explains, why using a (sharpening) steel keeps the knife sharper for much longer. We all have seen cooks wielding this item with the knife, and I always thought, either they are so incredibly good or they are showing off. Maybe both.

A leisure time cook on the other side, will have his problems with this device. I do not exclude myself from this (until recently at least). The crux is that a certain angle, coincident with the grinding angle, has to be maintained during this action. What makes it worse, is that nowadays you easily have at least two knifes with different grinding angles in your arsenal.

Juranitch invented this crafty device (shown on pictures 2-4 to 2-6) that rests with on a base on the table and has some reverse cone on the tip that serves as an angle guide to give your muscle memory a firm idea.

In recent publications I have seen a similar method advocated (bar the cone), using a stock sharpening steel with a handle in the left hand, with the tip down on some rag between it and the table, which securely locks the device. You may want to look up the book if it is not clear what I mean. (The book is available for free in one of the archives.)

Unfortunately the cone method relies on a single grinding angle. Actually, to be more precise, the angle guide determines a certain angle.
If one wished, a cone like that could be easily done with a 3D-printer nowadays, but this would again limit you to the angle it was designed for.

Now you´d be happy if a typical hobby cook or a housewife cared about their knives at all, letting alone such fine details. I am sure, if they were educated, they would be happy to use a steel. With the aid of a lookup table this would be very easy indeed.

One of the beginner sharpening instructions recommended to use a set of coins or an angle wedge or whatever contraption to raise the spine of the knife reliably and repeatably far enough to achieve a certain angle.
In the wake of this I saw a lookup table that gives a discrete number instead by using two parameters: knife body height and sharpening angle.

Now this very table can equally be applied to using a sharpening steel.
When I saw the program by forum member jvh I knew that I had to incorporate this into the program. The table is static, so it is ideally suited to printout.

I took the liberty to use jvh´s visual appeal and table functions; they are nothing less than perfect. The underlying geometry is nowhere near as complex, so no intent to compete with him. The table has been verified against the one I found on the internet for sharpening. Thanks jvh for the great job.

The table is locked to avoid unintentional changes, but has no password.
You can adapt it to your needs any way you like.
This method is nowhere near scientific, but gives you a much better starting point than being clueless.

Have fun,

-Helmut

And by the way... this works for your unobtainium strop too...

very nice, thanks.

Thank you tgbto,

I realize that I had the right notion about this program. It is the same geometry applied backwards compared to TormekCalc´s other program parts.

However, I do not have the MS Office programs needed to run it. The progam itself is absolutely reasonable, but not the Office part. Moreover I dislike the new style they introduced intensely.
It does not run on libreoffice.

But it´s easy enough to use Angle Calculator Lite and look up the table it generates. Instead of choosing a grinding angle and a projection value to look up a corresponding T-USB value one can choose a projection value and the measured T-USB value and look left for the corresponding grinding angle.

Of course one could modify the table to reflect this, but that appears overkill.

Well thanks for the inspirations so far.

I did know neither Dave Martell nor the forum that he wrote the article in until recently. Although he writes with confidence, I had not way of determining the truth in his words. Hence the reluctance...

I know the KnifeGrinder video. He only grinds one side. The facet is quite prominent, so IIRC he wanted a straight facet and not a hollow cut. I think a facet this size and that acute would not be possible on the circumference without hitting the jig.  But in fact this is how I thin my knives behind the cutting bevel. There is ways to true the side...

I am not sure how to use bevelcalc to reverse-engineer the geometry. I would be thankful for help here.

The knife I bought has the following shape (see attached file. source: A Basic Explanation of Asymmetry

note the drawing is much exaggerated. Kippington gives us an explanation for making a knife asymmetric from the start.

Interestingly, the knife maker recommends a symmetric grind at some low angle.

The shop that sold it to me thought that the knife is so tough that it hardly needs to be sharpened (Dave has said it...) but it will at some point.
A clad knife is tough, but not invincible.

The cutting facet is really small, maybe 1/2 mm on both sides, and it seems symmetric as far as I can tell. According to Dave, it should have asymmetric cutting facets, but I cannot tell the knife is steering to any side. With repeated grinding back the problem may arise (Kippington explains this in post#25) and then a firm knowledge of the original shape is needed. However, I can see that it only takes some very light touch-up with a japanese stone of sorts, and that can be done the traditional fashion.

So maybe we should leave it at that for the moment, until further wisdom arises.
Thanks,
-Helmut

So far I found out about Japanese knives:

In my experience with working with thousands upon thousands of Japanese knives I can confidently state that 99% are asymmetric with the majority being ground favorably for a right handed user.

(thread #1)

He mentiones that he does not know the reason for this.

and also

If you want your double beveled Japanese knife (which has a blade that has been either forged or ground asymmetrically) to cut straight and wedge less you will sharpen the edge bevels as close to matching the asymmetry of the blade itself.

To revisit the issue of myths, many EdgePro type device retailers will tell you to just pick an angle and grind more from one side than the other or maybe to count strokes (like 7 strokes on this side and 3 on another for 70/30 grinds;..they state that this will allow for correct asymmetrical ground edges.

• All Japanese knives are asymmetric; the entire blade is asymmetric; not just the edge.
• Use your mind and your hands to find the ratio of the blade and then mimic this within the sharpening of the cutting edge bevel.
• Adjust your angle of approach as need be - yes even if using a sharpening aid/device.

I do not know how credible the guy is, but he seems to be appreciated, and his arguments are plausible.

So this clearly phases out the koiknives recommendation from my preceding post for sharpening so many strokes to each side. Darn. This would have been easy to accomplish on the Tormek.

What the guy says about EdgePro certainly applies to any guided (wet-) grinder.
This means individual angles for each side.
This further means, better steer clear of such knives?

He says that virtually all Japanese knife-makers produce asymmetric knives - unless they were specifically determined for the Western market. Japanese technology in a European package...

Maybe stick to those...

Greetings,

I am in the verge of upgrading my cooking utensils with a Japanese Knife.
Edit: knife information updated.

As different to most of that league offered in Europe, that one, although being a double edged knife,  is ground asymmetrically at an unknown percentage.

This site (and others) recommends for sharpening:

If the double-edged kitchen knife is a symmetrical 50-50 V-shape, you will apply a similar number of strokes on both the front and the backside of the blade. However, if the front face has more edge than the backside such as in a 70:30 double-bevel kitchen knife, you will apply 7 strokes at the front and 3 strokes on the knife's backside.

This approach suggests equal angles on both sides, but on some other web page I have seen actual different angles specified for the respective sides (unless this procedure results in different angles, which I fail to comprehend).

The shop on the beginning mentions (in the blog somewhere) that the grind can of course be overridden with a standard 50/50 grind, but they surely have had some intention with that. (That said, it may not make a big difference.)
Edit: they have...

Masahiro's edge is its most important feature. The edge is 80/20 asymmetrical, rather than sharpened equally on both sides. The idea being that the asymmetrical edge is 35% thinner than a 50/50 edge. This fact makes Masahiro's knives sharper than other Japanese knife brands.

(Source)

We have learned that a primitive knife jig or a wrongly clamped knife will produce such a non-symmetry, albeit as an unwanted side-effect and probably vastly unpredictable let alone controllable.

Does anybody here have experience with such knives? Has anybody worked out a solution other than nerve-wrecking re-adjustments on tasks like de-burring? I found no reference to this neither here nor there.

Thanks,
Helmut