Leo Barr

[Leo Barr]

It took about 4 hours but to keep them this way is about 20 minutes work . I had about 9 or 10 knives from this 1 restaurant that the chefs had retired because the grinder had rendered them useless the head chef had replaced his Japanese knives with Victorinox since the grinder could just about coup with them so I had 3 Yanagi to restore in a similar condition to the one above the worst one was a cheap one a very big Global around 300mm because he had gone further into the heel of the knife worst thing is this particular grinder sells Japanese knives as well.

[Leo Barr]

Thats an interesting thought a sort of leather steel I think I may make one.

[Leo Barr]

I should have made a point of saying that deboning knives, cleavers & gutting knives I would not thin ; that aside most kitchen knives or even edc’s used for slicing perform best when thinned.
Many Japanese knives have a pronounced thinning bevel an American example of this are Carter knives when sharpening it is necessary to work on the thinning bevel before moving to the edge bevel.
Nice point brought up in braking down an animal the knives may well need to be twisted through joints to separate parts – a thinned knife may well snap.
One thing I imagine even when braking down an animal there are probable applications for both thick and thin blades.

[Leo Barr]

I thin most knives except some knives like Victorinox that is the thin ones.
I always put a bevel on the edge of the thinned edge.
Steel around the mid 50’s Rockwell will go like tin foil if the edge is too low an angle .
I made a mistake on a cnefits from thinning heap Deba I had bought that was a 56 on the Rockwell scale I took the secondary bevel to the edge having raised the angle about 1/3 of the way downI then put an edge bevel spanning from around 15˚ at the tip and 22˚ at the heel and then put a small micro bevel on top +5˚ ish the blade was good and sharp . the next morning I cut some cheese and bread it felt good – then I checked the edge again and it was blunt the edge I suspect had compressed so I re-sharpened the edge adding about 10˚ and all seems fine now.
I conclude that the soft steel just compresses when carrying too low an angle. Hard steel will tend to micro chip if the angle is too low.
These angles are unaffected by how much thinning is behind the edge (secondary – thinning bevel) soft or hard steel still benefits from thinning on the secondary bevel if there are noticable holders from the main grind to the edge it is fair to assume that the knife needs thinning . Best proof of this is that a metal spatular will cut a carrot with an unsharpened edge simple because the spatular is thin this proves the worth of thinning a blade I don’t use a vernier to measure thickness I just pinch the profile gentle working down from the spine to the edge it is possible to feel if the profile is too thick the shoulders are obvious. Best to thin progressively over several sharpening sessions if unsure of how much to do.
It is best once the angle for thinning is established for a blade to repeat the procedure on each sharpening so unfortunately no real time is save but the knife will cut very well as I said (race tuned).
I hope that helps a little it is much easier to do on laminated blades due to the soft cladding which is why I prefer Japanese knives.

[Leo Barr]

I think this is the way to turn out perceptively sharp blades I have to thin about half the knives I sharpen if I want to give a knife back that is shall we say race tuned otherwise they may as well sharpen their knives on a drag through device seems to be working mostly top restaurants are my cliental .

[Leo Barr]

Most impressed with the guy that won with his version of the Viking Battle Axe he used the most basic of forges a pan with a hair dryer stuck on a tube the result was probable not far from an original one rustic looking even the handle was hand carved all done in his garden.
Very inspiring makes me want to have a go at it sometime it looks possible to put a similar forge together with small change.
I suspect his most expensive tools were the anvil & hammers.

[Leo Barr]

mark good vid by Murray I must admit that the oil quenching looked dangerous in thew studio & Murray was lead astray from his gut reasoning trying to second guess what the judges wanted which highlights the point how competition of this sort does not improve the competitors craft on the whole.

[Leo Barr]

I have been downloading the episodes from torrent sites.

It is quite enlightening watching how nearly every contestant fails in some way due to not listening properly (competition stress).

i think the Murray carter episode was most interesting one so far I guess the winner in that particular episode knew the Kris more having made two in the past & Murray overlooked the chopping aspect of the weapon.

I agree with tcmeyer that there is too much reference to the kill capabilities of the knives.

It appears that the stress of competition & time influences force mistakes but what it does teach to the viewer is perhaps many of the negative points to look for in a knife I have certainly learned things.

It would perhaps be interesting to see another series where contestants were given more time although I think I would prefer to see a different lineup of judges perhaps an audience of knife makers to judge the creations .

Some of the test on the knives or swords were interesting & should be included perhaps in future reincarnations of the show.
It is still difficult in that so many tastes prevail even from continents. North America seems to like combat knives whilst parts of Europe prefer gentleman’s knives.

Lets hope there are more shows on a similar line.

All in all the show is compulsive watching .

The one negative is that some of the best in a field are not necessarily good at competition and that is true of many sports or artisans.

[Leo Barr]

This is Kenneth 123 doing the zero grind

IU thought this may be helpful

[Leo Barr]

You can still tune the blade so to speak by thinning behind the edge , then steepening at the edge.
I took a Chinese 2$ knife and did a zero grind on it I left a little thickness at the edge it cuts extremely well all things considered (razor sharp but not too delicate).

[Leo Barr]

Often thinning takes time and either using the weps or freehand it pays to thin in increments nothing ever goes well if you get bored an honyaki nakiri of mine took around 4 hours to thin but it needed it I think some of the clad paring or petty knives are often too thick Tojiro is one make in particular even though it means thinning away some of the damascus cladding then knife is better for it.
You are right you cannot put it back if you take too much away but bear in mind a steel spatular for spreading filler often cuts carrots exceedingly well unlike a razor sharp axe.
Thinning a low angles should be done slowly when the knife next needs attention search for micro chips that is often a sign of either misses or the blade reaching its limits.
I think the biggest decider on the matter is the user some people really mistreat their knives whilst a careful user can use a knife that sticks in the cutting board with made of very average steel with no blade damage.
In reality in both blade & edge geometry has no finite numbers the higher quality Japanese knives have no recommended angle since it is down to the user how they like their blade.

[Leo Barr]

One thing to note micro bevels really do not take much to add to an edge you can create an almost invisible micro bevel just by doing 2 passes each side with your finishing stone when you have this the knife will cut as if it is a low angle say less than 15˚ or lower but it just makes the edge a little more robust I also then do one honing stroke on the micro bevel with either a 1K or a 600 grit just to add a little more bight to the blade.

[Leo Barr]

If it did have an 80/20 grind you can use the same angles each side just on the right side I would work that bevel almost through to the authorised then repeat the angle on the other side just enough to get a slight burr with luck you should have something like an 80/20 the other way to do it is count so 8 passes on the right to 2 passes on the left the idea is that the edge should be below your centre of effort so if the blade is offset then the bevel should be at the lowest point since the left hand side of the blade should be a lot flatter so the edge will be much closer to the fatter side.
I think I am probable succeeding in making it sound more complicated than it really is it is not an exact science the blade smith will not have sophisticated tools to set perfect angles so accept a sort of mas or menus approach to it the most important part is to have the same angle each side if you find it steers when cutting through a big melon note the direction it is going so if it is left there is not enough bevel on that side or vice versa I have not had to do this but I think that is the way it works certainly if you think about it say if it was a single bevel the knife would steer to the left on a deep cut since I think the bevel would eventually would try to run parallel with the cut I admit not been much of a melon fan I have not tried it either way you could prove this on a junk knife put a single bevel on it and see how it steers I would hazard a pretty good guess and say that if the knife tracks left then it needs a bit more bevel on the left to compensate . I am pretty certain I have it right please do correct me if you set up an experiment with a junk knife on a melon and find I have it the wrong way round I do like to see the mechanics of something over pure theory much easier too grasp.

[Leo Barr]

You may well find that if you look from the tip to the handle that the whole blade is from spine to edge off the centre line often asymmetric knives are.
My big thinning jobs were the result of someone just sharpening the edge and even increasing the angle . Provided on a thicker knife that the thinning bevel & the edge bevel are sharpened each time it should never be necessary to thin. I find on Macs for instance that once about 15-20% of the blade has been sharpened away it is necessary to thin. Often bad use of steels will require that once the waves are removed it is necessary to thin.
All single bevel knives should be sharpened from the shinogi and the the edge each time especially on debas that may be as wide as 5mm on the spine.

[Leo Barr]

Macs do have very hard steel which is fine until they need correcting either a wavy profile due to aggressive use of a steel or need for thinning.
I had one to do last week that was completely messed up the edge was so misshapen it looked like a butchers knife and the spine had been ground.this was one I had to reshape using my belt sander it probable took 20 minutes before it resembled a gyutu (that was after re grinding both the spine & the edge) I do not sharpen with a belt sander this I do on whetstones it still took a while since it needed thinning probable 8-10˚ before micro beveling.
It is a shame Macs are not laminated it would make corrective work much easier. Still the steel is good. I should have taken photos but it was part of a batch of knives I had to do and every minute counted . There was a yanagi which needed a lot of thinning and although laminated it was extremely tough steel & took 4 hours or more to do. That one I did photograph.

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