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a good video for perfectionist knife sharpeners

Started by Ken S, July 06, 2023, 11:53:54 AM

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tgbto

Quote from: 3D Anvil on July 11, 2023, 04:35:37 PMI don't think you can guesstimate a BESS score from the paper test.

Well the idea was that there was no evidence of sub-60 BESS scores. And I stand corrected, according to Wootz' scale, paper slicing is 300 BESS and below.

3D Anvil

So I did the test I mentioned earlier: two identical Victorinox 6" knives, both sharpened on Tormek.  One was honed/stropped on a rock hard felt wheel, also on the Tormek.  The other was honed/stropped on a Work Sharp Elite using leather belts, at the lowest available speed.  In both cases, the first pass was at the sharpening angle +2° and the second pass was at the sharpening angle (15°). 

After some hand stropping to equalize the results, both knives measured 105g on the BESS tester. 

Test consisted of slicing up 5 carrots and 1 sweet potato per knife, on a wood cutting board.

Conclusion: no significant difference.  The average of three BESS tests in the cutting area came out to 245 for one knife and 247 for the other. 

I'm going to put it up on Youtube when I have a chance.

Sir Amwell

Interesting 3D.
So edge retention seems not to be compromised by the different honing methods.
So any potential over heating by using the WSKO leather belts seems not to affect the edge retention.
What is of interest to me is how quickly the sharpness decreases with these pretty standard kitchen tasks?

3D Anvil

Yep, that was my conclusion.  I don't think the leather belts create near enough heat to affect the temper of the edge.

As far as the change in BESS score goes, it didn't surprise me.  These were at the low end of Victorinox's line, costing $21 each.  They don't even state what the steel is, but it's probably 8cr4mov or something along those lines.  Maybe 55-58 hrc?  Also, the average factory edge comes in around 210 BESS, so the end result wasn't far off from that.

3D Anvil

For what it's worth, here is the video of my honing edge retention test: https://youtu.be/A8xEQqrjbDM

Sir Amwell

Loved the video 3D. Make more!
As an aside, as commented earlier on about the drop in sharpness after the the test slicing/ chopping which I found surprising. I think that using your knife to push sliced food away across the chopping board by scraping with the knifes edge seriously dulls the edge. It doesn't affect the validity of your results as you did pretty much the same with both knives.
I always tell my customers not to use the knife edge to push/scrape the food away on the board.
Get into the habit of using the spine of the knife to do this. Retention will be much better.

3D Anvil

 Thanks, man!  The irony is that I'm always on my wife not to drag the blade sideways across the cutting board.  However!  If you pay attention, you'll see that (I think) I only used the blade side that way one time.  Otherwise, I'm using the spine-side of the blade to collect the cut food.


tgbto

Quote from: 3D Anvil on July 15, 2023, 05:58:47 AMYep, that was my conclusion.  I don't think the leather belts create near enough heat to affect the temper of the edge.

My two cents : I sometimes hone on the WS Elite/BGA with the leather belt, and I don't expect much heat production that way. In the video by the OP however, the speed seems much higher (and the high-volume high-pitch sound produced seems to back this up).


3D Anvil

Quote from: tgbto on July 17, 2023, 08:51:28 AM
Quote from: 3D Anvil on July 15, 2023, 05:58:47 AMYep, that was my conclusion.  I don't think the leather belts create near enough heat to affect the temper of the edge.

My two cents : I sometimes hone on the WS Elite/BGA with the leather belt, and I don't expect much heat production that way. In the video by the OP however, the speed seems much higher (and the high-volume high-pitch sound produced seems to back this up).


I agree.  The leather wheel he's using sounds a lot like a paper wheel on the grinder, and I find that paper wheels introduce a lot more heat than leather belts, even with my 1/2 speed grinder.

tgbto

From what I can see on the video, it looks like he's using a wheel made with stacked leather discs, and the honing is done with the side of those discs. So yeah, I think friction is much higher than on a Tormek with the smooth leather wheel.

HaioPaio

Lots of assumptions about the speed of that leather disc wheel have been made here.
The RPM control at the machine seems to be set to a low RPM.
I could not find any information about the actual RPM in that video.
So, I do not know if it runs fast.

cbwx34

#27
Quote from: HaioPaio on July 21, 2023, 12:50:23 PMLots of assumptions about the speed of that leather disc wheel have been made here.
The RPM control at the machine seems to be set to a low RPM.
I could not find any information about the actual RPM in that video.
So, I do not know if it runs fast.

Well, here's the grinder (a Shop Fox W1839 that it says runs from 2000-3400 rpm), that he's apparently running in the middle of the range based on this

 ::)
Knife Sharpening Angle Calculator:
Calcapp Calculator-works on any platform. New url!
(or Click HERE to see other calculators available)

3D Anvil

Quote from: cbwx34 on July 21, 2023, 03:27:21 PM
Quote from: HaioPaio on July 21, 2023, 12:50:23 PMLots of assumptions about the speed of that leather disc wheel have been made here.
The RPM control at the machine seems to be set to a low RPM.
I could not find any information about the actual RPM in that video.
So, I do not know if it runs fast.

Well, here's the grinder (a Shop Fox W1839 that it says runs from 2000-3400 rpm), that he's apparently running in the middle of the range based on this

 ::)

You also have to consider that it's a 6" wheel, so it will be considerably slower (feet per second) than an 8" or 10" wheel rotating at the same speed.

Ken S

When I posted the link to this video, I did not anticipate the amount of attention using a higher speed buffer would receive. I have never owned or used a buffer. I also have not used my dry grinder in a dozen years.

Discounting the higher speed buffer, I still believe the video has value. I was impressed with the more in depth understanding of paper tests he demonstrated. He also demonstrated a practical efficient command of using his digital microscope.

Ken