The BESS Exchange is sponsored by Edge On Up - Edge Sharpness Testing

The definition of 'blunt'

Fri, 02 Feb 2024 13:54:53 +0000

Hello All, perhaps a strange thread on a sharpening and sharpness forum, but it seems I may need an arguable measurable definition of 'blunt'.

In the BESS scale, it is defined up to 2000 where there is an unsharpened DE blank quoted (assuming this is an unsharpened razor blade blank), also compared to a butter knife.

Can I safely say that an edge measured at 2000 BESS or above is 'blunt'?
If the answer is yes, does this have an equivalent, directly measurable, edge apex width?

Has anyone else needed to define when an edge is officially blunt?

Addition:
Might there be a cutting test that a 'blunt' blade will demonstratably fail as a proof?

Avg BESS score for cheap kitchen knife?

Sun, 23 Apr 2023 22:12:05 +0000

What’s a decent score for the average cheap kitchen knife like a Henckles or Wusthof chef knife?

I’ve been sharpening lots of these knives for neighbors and trying to find the balance between a quick sharpen on the belt sander (~5 min) and a decent keen edge. I am scoring around 150-175 while sharpening at 20 dps.

These are very soft stainless steel and I worry that if I try to go sharper or a steeper angle the edge will roll almost immediately. The steel is so soft that I can usually push a new burr just with strong finger pressure.

Protocol for BESS measurements?

Wed, 19 Apr 2023 17:35:23 +0000

For any measurement method, it is important to apply an established measurement protocol.

For example, for outdoor temperature measurements, it was once agreed that this is done at 1.5 meters above the ground, in a cabin painted white, where the wind can blow through and the sun cannot penetrate, etc.

Is there also such a protocol for BESS measurements?

I ask about this because I saw a video on FB that a BESS device is a waste of money. If you press the wire quickly you get a lower reading, than if you press the wire very slowly.

Would like your response.

0g Score Possible?

Wed, 16 Nov 2022 17:36:29 +0000

A knife sharpening outfit called Burrbenders has several videos out showing a BESS score of ZERO, and others with scores <5g. Is this even possible, assuming the test media is real and the test is being done correctly? In the video the guy doing the test isn't using the fulcrum, and he's moving too quickly, but even then, a 0 score is mind boggling.

Link: Burrbenders Sharpening (@burrbenders) • Instagram photos and videos

Rubber bottom cap for DCB10?

Thu, 11 Aug 2022 17:02:35 +0000

20220811_182243 copy.jpg (Size: 360.88 KB / Downloads: 3)

I finally got my complete set of EDGE LAB A today.

I'm happy with my
KFL10R Knife Fulcrum, SLCF20 Slice Test Fixture with strong magnet
ATF10G Test Fixture with quite stable rubber bottom
CNC10 SLICE GLIDE, SLCP10 Slice Plate are even more tighter with screws

But, DCB10 Test Clip Base has slippy untreated bottom.
I'm pretty sure even with bare bottom of DCB10 Test Clip Base do not influence accuracy of the BESS test, but why not add more stability?

Always the more, stable the merrier.

p.s. I just realised I forgot about add EdgeOnUp ATF10C Test Fixture

Prototyp Bess measurement

Thu, 12 May 2022 23:58:46 +0000

Structural Edge Testing

Tue, 14 Dec 2021 11:03:09 +0000

Hello All, I seem to have been away a while, and may not be up to speed with the latest on the SET.

I did try a couple of searches for 'Structural' and 'SET' but didn't find what I thought might be some more established threads on this (please point me at them if I missed them).

How has everyone ben getting on with their SETs? Are there any tweaks, or hints for getting clear results?

If I were to summarise my own findings I'd say the first challenge is the consistency of the testing edge. My results are showing inconsistencies which I am sure are due to the consistency of the edge from test sample to test sample.

So far I find that unless an edge exhibits chipping, I can virtually guarantee that I can strop the test area back to a sharpness either identical or often better than the starting sharpness (although usually there is a visible sign of the testing site).

It feels like the results I have so far don't quite match with expected performance, so I'm questioning the value of what I've done so far.

I've got some blades incoming where I would like to show a clear difference with the SET. With a 58HRC and 64HRC version of the same blade there should be a significant observable difference.

What is the current thinking on this?

please assist with 150 BESS score

Sun, 17 Oct 2021 00:37:49 +0000

I received a PT50A just a few days ago, and have tested 8 knives with it so far. My best scores so far are a few of my kitchen knives, 100, 97, 98.

While I wish to improve those further, my primary issue is an 20CV folder. I have tested after sharpening 3 times and always get a score in the 150-158 range. My old CATRA goniometer shows a mildly convexed (freehand) edge around 18 dps. Over the last couple days I verified that with this edge I can clean shave arm hair in both directions, tree top arm hair against the grain, shave curls off of hair, push cut rolling paper along its length (but not on the short side), filet notebook paper, and dry shave stubble from my face with very mild skin irritation (no redness or blood weeping). After cleanly slicing notebook paper and push cutting rolling paper several times, the BESS worsened to 167. After that, I did 5 passes per side on crox followed by 10 per side on plain leather, and the score went back to 154. I have looked at the edge under a cheap pocket microscope that claims 100X magnification, and it looks pretty clean. Am I dealing with a burr? I thought the scores would get much worse after cutting if so. Is the ~10% increase in force indicative of a problem? All the references I see (primarily the knife deburring pdf I just purchased as well) say the BESS score would be much lower for the other cutting "tricks" I'm doing.

Typically, my rough grinding is done on a variety of things, diamond, SiC, etc, then 800 King or 1200 Sigma Power > 4000 King > 1.0 micron diamond on leather strop block or 13000 Sigma Power > 0.5 micron diamond on leather strop block > chromium oxide on leather strop block > plain horsebutt strop block. On the stones I generally scrub until there is a palpable burr, then do solely edge leading alternating strokes to remove. The strops are all of course edge trailing.

I have the full set of DMT diasharps from XXC to XXF, I'm thinking of using the 3 micron XXF then moving to the diamond strops. Should I expect better deburring and improved BESS scores? I don't use jigs, so I'm not sure how low a score I can get. I sharpen other knives (particularly fixed blades) around 13 dps +/- natural freehand deviation, but have kept the bevel width about the same as original on this 20CV folder.

New products - Edge Lab

Sat, 03 Apr 2021 07:15:50 +0000

https://www.edgeonup.com/Edge-Lab.html

Knife Grinders and AKM Propose New Study

Fri, 22 Jan 2021 16:09:36 +0000

Knife Grinders and Australian Knife Magazine, in conjunction with CATRA, are proposing a new and comprehensive study of the cutting attributes of various knives. The following is a link to the Australian Blades Forum where additional information may be found.

https://www.australianbladeforums.info/f...ine/47288-

Precision Sharpness Testing Device

Sun, 01 Nov 2020 15:03:17 +0000

Hi all,

I read a lot here in the forum and noticed that there can be some problems with the measurements if the user makes mistakes unconsciously. That is why I built a device that should deliver absolutely reproducible results (sorry, german language only, but I'm sure you will understand the function):

I used the BESS line and various fishing lines with the device. The lines are:
CE = Carbon Carp Expert 0.25 mm, measured 0.29 mm
TC = Tectan FCC (Fluorocarbon coated) 0.25 mm
TF = Tectan Fluorocarbon 0.25 mm
PF = Perca Forellen-Schnur Spezial Coating 0.25 mm
CF = Cormoran Profiline Forelle 0.25 mm
Unless otherwise stated, the thread tension is 100 cN for BESS and 300 cN for the other lines (1 cN ~ 1 g).

The first series of measurements was disillusioning. I expected better reproducibility:

  EN1-Bess-TC.png (Size: 12.55 KB / Downloads: 21)

Now other fishing lines were compared with the BESS thread:

  EN2-fishing-lines1.png (Size: 15.73 KB / Downloads: 17)

The BESS values show the greatest spread. Scattering? No, always an increase. I noticed this during the measurements (i.e. without a diagram) and before the last 3 measured values, the blade was wiped with dry kitchen paper. The following value was significantly lower. The last two values show the typical increase again. Hypothesis: the BESS thread leaves tiny deposits on the cutting edge that cannot be seen with a magnifying glass. Another thesis: these deposits were removed by the CE thread (decrease in the required cutting force).

Now the cutting edge was cleaned with dry kitchen paper after each cut:

  EN3-Bess-TC.png (Size: 8.95 KB / Downloads: 13)

Up to the tenth cut, the cutting force decreased and the values are below those in the last figure. After that there is no further improvement, but the reproducibility is finally as good as I expected.

The knife position remains unchanged. In order to see whether all threads require a higher cutting force with increasing number of cuts, 10 cuts were carried out without intermediate cleaning. This was followed by thorough cleaning of the cutting edge with dry kitchen paper. The findings:

  EN4-fishing-lines2.png (Size: 32.58 KB / Downloads: 12)

The Tectan Fluorocarbon line works best, which according to the packaging consists of 100% PVDF (polyvinylidene fluoride). The BESS thread shows the greatest increase and the greatest spread. Originally I had the secret assumption that the BESS thread was just a fishing line. Now a special coating seems likely to me. In addition, the fishing lines only require about 30 cN cutting force with a razor blade, while the BESS line requires the expected 50 cN.

Now the cutting edge has been cleaned after each cut. The following diagram shows that a defined thread pre-tension must be applied for reproducible values:

  EN5-Bess-tension.png (Size: 11.03 KB / Downloads: 13)

Validity of manila rope edge retention testing

Mon, 19 Oct 2020 15:46:38 +0000

I am about to embark upon some edge retention testing that I have not previously quantified with the BESS tester - manila rope cutting.

For my testing I plan to use 1" rope with a minimal wrap of insulating tape (just enough to overlap and completely cover). The use of the tape is three-fold; firstly to stop the rope unravelling, secondly to keep the fibres tightly together to try to make the material more consistent for each cut, and lastly to hopefully allow me to reduce waste by cutting off smaller sections as it is all held together.
I'd mark off a section of blade to 'saw' with, maybe 3" long, and cut onto a pine board.

Clearly I'm not proposing anything new with rope cutting itself, but maybe the full test process I'm going to use has not been tried.

What I have seen others do is to keep cutting (counting the cuts) until the edge won't get through the rope (or the effort is too high), or to cut a sheet of paper, cut the rope, and then cut the paper again, stopping when the paper is torn rather than sliced.

With the right slicing action I have been able to slice paper with an edge up to 400 BESS, so the paper test is not all that revealing to me.

My take on this is to instead introduce the BESS test perhaps after every cut of the rope (to be decided). Even if I never reach the point it won't cut the rope, I would have a log of cuts vs BESS.

There are many problems with this test including blade geometry, length of edge used in the cut, apparent effort (affected by the handle shape/size), batches of rope production etc, so I know it is flawed. To date, my work with the very controlled SET has found various anomalies and poor SET performances for blades that seem to do very well in real world use.

Has anyone already done this or have results proving or disproving the validity of rope cutting testing?

Too sharp?

Fri, 11 Sep 2020 19:11:46 +0000

I just sharpened a knife and decided to make a salad. Someone needs to invent a edge sharpness tester so we can know how sharp our blades are before using them. I just hate it when this happens!

50 BESS is the size of COVID-19

Tue, 28 Apr 2020 22:11:14 +0000

Just realized that the edge scoring 50 BESS has an apex of the same size as the coronavirus COVID-19.
Actually, apex in the best disposable shaving razors is even less.

This is the way to do it

Wed, 22 Apr 2020 21:33:32 +0000

The following was sent to us by one of our international customers. The picture shows how the test media passes beneath the bearing seat and is pinched between washer and test fixture when the clamping nut is snugged up. Atop the bearing seat is a thrust bearing. This arrangement insures that test media cannot be over-tensioned when tightening the clamping nut. Thanks for the picture Chico!

ATF TM Placement.jpg (Size: 142.13 KB / Downloads: 51)

Tricking the BESS Tester (without meaning to)

Wed, 25 Mar 2020 17:33:16 +0000

I just did some more work on my (now world) famous Tramontina kitchen knife. The one that scored about 190-ish after very careful deburring, following a 380 grit belt. Well I decided to polish it a bit so I used a 600 grit belt, then leather, scotchbrite, leather again. Terrible scores! 200, 350... So more polish. I went straight to a smooth leather belt with green compound. Very little compound left on the belt, but it's there. Eliminated the remaining LOW. ...and it scored 125, 125, 175. The 175 was in the curve. So back to the loaded leather. I did 5 or 6 passes and got a little too casual with my motions. Sliced open the top of my index finger. Ooops. Nice *cleeeeeean* cut though. It didn't even bleed for 20 or 30 seconds.

After cleaning that up, I tested the curve again. One handed, because I was holding pressure against the finger of one hand. Balanced the blade on the fulcrum on the tester, and leaned it over to the media. Lean, lean, lean, lean... and the media broke. At 80 grams. No freaking way. I must have sliced it somehow.

So I went and got a bandaid and got my finger taken care of. ...and tested again. In the curve with the fulcrum, but this time with the other hand on the tip of the blade helping to guide it down. ...and it read 135. Now that's more believable.

I can only guess that with one hand the blade slips some and creates a slicing motion, which obviously "tricks" the tester because the force is not straight into the media, it's at an angle. I think if you were really clever you could slide the blade sideways and get nearly zero readings by doing an extreme version of this. Does that sound about right?

Anyway, seems like I need to be more careful when sharpening knives.

Brian.

TM02 vs DTC100

Mon, 10 Feb 2020 08:59:25 +0000

IMG_2072.JPG (Size: 1.8 MB / Downloads: 3)

I tested it with DE razor blade.

[Test 1]
TM02: 63, 63, 64 (avg: 63.3)
DTC100: 51, 54, 45 (avg: 50)
>>> TM02=DTC100+13.3

[Test 2]
TM02: 66, 69, 76 (avg: 70.3)
DTC100: 43, 51, 49 (avg: 47.6)
>>> TM02=DTC100+22.7

[Test 3]
TM02: 63, 73, 64 (avg: 66.6)
DTC100: 59, 55, 52 (avg: 55.3)
>>> TM02=DTC100+11.3

[My Conclusion]
1. The score measured by DTC100 is abt.10~20 BESS lower the score measured by TM02.
2. TM02 = DTC100+15 BESS

Which knife sharpener is best?

Tue, 28 Jan 2020 07:11:15 +0000

Which Utility Knife Blade Is Best?

Tue, 17 Dec 2019 11:07:37 +0000

**New Record, Sharpest Knife , 4 BESS, Kknives Switzerland.

Thu, 28 Nov 2019 19:02:14 +0000

Roman Káse from Knives Switzerland
Using Nitrobe77 at 64rc.