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Are thinner knives sharper?

Started by Ken S, February 22, 2017, 12:25:56 AM

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Ken S

Today I sharpened two of my kitchen knives. One, my twenty five year old Henckel German style eight inch chef's knife, is a heavy, traditional design, with a thick, tapered body and a substantial bolster. I had sharpened it using the Tormek method several months ago, and have maintained the edge using a ceramic steel. It had a BESS reading of 350, respectably in the range of factory new fine cutlery, but nothing to brag about.

The second knife is my Kitchenaid $12 grocery store santoku knife. I recently changed this knife from a sharpening knife to a working knife. I have been very pleased with its performance; it can easily make very thin slices. It was quickly sharpened with a 180 grit CBN wheel, and maintained with the ceramic steel. It had a BESS reading of 320. Again, this was factory new fine cutlery range, but nothing special.

I ground both knives using the SG-250 graded fully fine and then with the leather honing wheel. I gave each knife reasonable, but not extraordinary care in sharpening. The Henckel now reads 200 BESS. The Santoku now reads 150 BESS.

It amazes me that a twelve dollar knife outperforms a knife costing six times that amount. Both have been sharpened to fifteen degree bevels (combined thirty degrees). I have not used the santoku enough to have a good sense of the edge endurance. I do know that I can consistently cut thinner slices of apples and cheese with it. I will keep it with the active duty kitchen knives.

Ken

SharpenADullWitt

There are several factors that determine what a knife costs, so using that as a metric has its issues.
Knives are made typically in two ways; forged or stamped.  Then you have quality of the metal, as well as mix of the metal (German knives for instance, have certain specs they must state on the knife).  Then labor costs (costs less to make a knife in China or Brazil, then it does in the USA or Germany).  Then style of knife, as a German chef's knife, will get used in more of a rocking fashion, then an eastern style santoku, which is more of an up and down motion.
Other factors in the comparison, would be weight, which might hurt an edge more coming down on it.
It doesn't surprise me any.  I have said before that I could use a $6 Update International restaurant supply style chef's knife, and have a much better value then a hundred dollar Wustoff.
Favorite line, from a post here:
Quote from: Rob on February 24, 2013, 06:11:44 PM
8)

Yeah you know Tormek have reached sharpening nirvana when you get a prosthetic hand as part of the standard package :/)

Herman Trivilino

Quote from: Ken S on February 22, 2017, 12:25:56 AMIt amazes me that a twelve dollar knife outperforms a knife costing six times that amount.

I'm interested in knowing how well the two knives' edges hold up in regular use. It would see, the more expensive knife would hold up longer, but being heavier it may be subject to more forceful cutting board collisions.
Origin: Big Bang

Ken S

Herman,

I do not have a preconceived answer, and I know there may be several variables. I am just curious.

Ken

ps I did notice that, trying to standardize the sharpening procedure, the SG-250 graded completely fine, 1000 grit, seemed too fine to grind efficiently. Next time I will aim for a middle grit between 220 and 1000.


OBR

Ken,

I'm curious how you determined that the SG250 at 1000 grit was too inefficient as you ground your two knives. As I'm sure you can guess, I'm asking because I'm trying to determine what grit would be best for a CBN wheel mounted on my T7 for my knife sharpening enterprise.

Curt

Ken S

Excellent question, Curt.

The two knives I sharpened were just not sharp. There was no damage to the edges. The BESS numbers I posted put the edges in the acceptable range of factory new cutlery. In fact, I pulled both from the active duty knife block (my only knife block).

I should have counted the number of strokes necessary for each bevel. I recall it was around eight to twelve. The SG-250 happened to be new and trued at the start of the session. I spent some extra time with the stone grader insuring the wheel was as fine as possible. I have no way to verify the exact grit. The wheel felt very smooth.

I normally grind knives in the horizontal, edge trailing position. For this test, I used the more aggressive vertical, grinding into the wheel position.

Unlike your operation, I only sharpened two knives. Even at this very low volume, grinding seemed to take too long. In your case, my gut feeling is that 600 grit would be a good balance of speed and smoothness. As much as I like the cutting action of the SG and SB for knives, with the volume you handle in a short period of time, I would go with CBN and sidestep wheel dressing.

Do not forget that new CBN wheels cut very aggressively when breaking in. The break in period is a good time for any nasty knives you have been postponing. Your wheel will soon cut properly for its grit. You will feel when it is right.

The choice would be between 600 and either 360 or 400 grit. I don't think you would go too far wrong with either.

Herman Trivilino

Quote from: Ken S on February 22, 2017, 11:25:00 PM
ps I did notice that, trying to standardize the sharpening procedure, the SG-250 graded completely fine, 1000 grit, seemed too fine to grind efficiently.

That has been my experience, also. I used to hold the opposite opinion, based on advice from Jeff Farris and some limited experience sharpening knives that just needed touching up.

Nowadays I find myself waiting until my kitchen knives are too dull to be refreshed with a steel. In that case they need the 250 grit because the 1000 grit just will not raise a burr. Of course I then follow that with the 1000 grit and the leather honing wheel.

Pocket knives, on the the other hand, should probably be sharpened with the 1000 grit. For such small blades the 250 grit removes too much steel too fast. Unless they are quite badly damaged with nicks and gouges. Come to think of it, this may have been the source of Jeff's advice because he sharpened so many pocket knives for would-be customers at demonstrations and trade shows.
Origin: Big Bang

RichColvin

Hermann makes a great point about pocket knives.  I use the Japanese stone for my pocket knives for that reason (& because it makes for a sharper edge).

Kind regards,
Rich
---------------------------
Rich Colvin
www.SharpeningHandbook.info - a reference guide for sharpening

You are born weak & frail, and you die weak & frail.  What you do between those is up to you.

Ken S

With all due respect to our forum founder, Saint Jeff, I believe his knife video downplayed using the stone grader with knives. Jeff brought a storehouse of practical Tormek experience with him. We are indebted to him. I personally have learned so much from his writings and videos. However, we must not forget that he made his living selling Tormeks, and needing to regrade the grinding wheel doesn't usually play well with the newbies.

One thought, with microbevels, only a very narrow micro or secondary bevel is necessary, because only the very front on the edge does the cutting. Therefore, why should the thickness of the knife or tool matter?

Ken