Hello folks-
Recently I've been seeing something that's either incredibly awesome or incredibly disappointing, namely some zero BESS readings on a knife sharpening company's page. Now, they DO have some pretty impressive (think very!!) non BESS results- IE shaving wafer thin bits off of an unsupported cork, slicing an onion with an axe, etc. They make a point of showing several zero BESS readings. Now, I think this is where the bullshit comes in. First, please correct me if I'm wrong, but doesn't the BESS tester measure grams of force applied? So even if the knife is extremely sharp, it should still register one BESS at least? Secondly, this person makes a point of using the BESS tester without the pivot. Watching their technique, I don't see any slicing going on, just a straight push cut, but this still seems suspect to me. Another idea I had was that they had somehow calibrated their tester (like taring a scale) to the equivalent of 45 or so BESS- while still extremely impressive, this would still be faking results. My other thoughts are that the testing media is far over tightened, resulting in a BESS reading that averages consistently lower. And lastly, even our own Wootz (A very sad loss- he contributed immensely to this community and the science we use) was not able on his best day to come within this range. I know many people here view him as one of the foremost sharpeners here, and it seems peculiar to me that some non scientific knife sharpener could outdo him sheerly by accident. They also don't show any of their processes. So- these are my thoughts, I'm curious to hear other ideas. Is a zero BESS reading even possible? I'm unsure if I should mention this person publicly, but would be happy to do so if that's within etiquette rules. If this person actually has created a process that can consistently and reproducibly make zero BESS readings, without any funny business, I will first eat my hat and then proceed to be extremely impressed. Bravo to them if that's the case.
I think it's impossible, but even if he somehow did record a 0 BESS score, my understanding is that these testers aren't particularly accurate below around 35g. The best (BESSt?) I've managed is a score of 45g. on my PT50B, which rounds to the nearest 5g.
Do you have a link to the site? I'd be curious to check it out.
Well if we're speaking from a theoretical point of view, anything that would fall within half of the scale resolution would get a zero BESS reading.
That being said, something sharp enough that it would cut the test media with less that half a gram of force, I find highly dubious. I guess there are ways to cheat the measurement : overtightening the test media is a known one, but laying down a drop of liquid nitrogen onto it would probably make it quite fragile as well. Maybe heating the blade before taking the measurement as well ? Who knows...
I think I remember the sampling frequency to have a significant influence as well, so maybe if you record several measurements when you press down very quickly with a low sampling frequency, you'll get a few where the scale takes two consecutive readings at zero...
After some thought I've decided to include the guy's page. It's a public business account on Instagram, and could reasonably be found after some sleuthing. Look up burrbenders on Instagram. That being said, it's not my intention to hassle this fellow whatsoever- I'm just curious about his claims and seeing what other people think.
Why not ask in the BESS forum (http://bessex.com/forum/)?
In one of the Burrbender videos, he claims that BESS calibrates the machines by using a blade that gives a zero reading... ???
I'd ask over there.
Quote from: cbwx34 on November 15, 2022, 04:12:56 PM
Why not ask in the BESS forum (http://bessex.com/forum/)?
In one of the Burrbender videos, he claims that BESS calibrates the machines by using a blade that gives a zero reading... ???
I'd ask over there.
I agree that a test result of zero sound bogus, but I also agree that this should be checked by posting on the BESS exchange or directly with Mike Brubacher (edgeonup@gmail.com), inventor/founder of the BESS test instrument.
Rick
Excellent idea cbwx34, and thank you Rick for the contact info. I'll send an email to the BESS folks after things calm down over here.
I posted the question on the BESS forum (testing subforum), but it doesn't seem to be very active over there.
Quote from: sharpening_weasel on November 16, 2022, 06:28:05 PM
Excellent idea cbwx34, and thank you Rick for the contact info. I'll send an email to the BESS folks after things calm down over here.
Where are things not calm ?
Midterms.
Oh dear, I got it now. Well, there were answers to @3D Anvil's post on the BESS forum, and quite the tongue-in-cheek one from the Edge on Up team ... Here it is :
QuoteQuite the video you sent along, 3D Anvil, and thank you for the effort in doing so! We can offer the following in an effort to help you with your question:
Edges cleaved from obsidian glass produce the sharpest edges (at least to the extent of our awareness). Obsidian glass material is capable of producing edges many times sharper than any edge composed of steel.
They say that an expertly cleaved obsidian cutting edge can have a total thickness of only 4 nanometers. Assuming a properly conducted sharpness test and, if said obsidian was subjected to that sharpness test, such an obsidian edge would then produce a theoretical BESS test result of 2 (total thickness = 4, radius of edge = 2 nanometers). Apparently, the obsidian scalpels we tested some time ago weren't as expertly cleaved because they ran BESS 3 - 5.
With consideration for the above, we feel your "bogglement",
Edge On Up
So yeah, that was baloney all right...
I read both responses. I can see how one might think EOU's response was tongue in cheek, but from the experience I've had with EOU, that could also be a genuine, direct and factual response. They did develop the technology and went through extensive testing. If anyone knows what the sharpest edge is, I think they'd in close contention.
But... given the complete ridiculousness of the original claim, who could blame them for taking it as a joke.
Rick
I agree with you. I just thought the answer managed to be very factual and at the same time masterclass-level irony.
- " This guy pretends he got a 0 BESS reading with a steel knife. That is mind boggling.
- The theoretical minimum BESS for an obsidian blade is 2. We feel for your bogglement."
LMAO.
Yep, that's pretty much what I thought. I have no doubt that the Burrbender folks are excellent sharpeners, but there's something fishy with those test results. Not questioning their integrity, though. It's possible that their scale isn't working properly.
I follow some very accomplished sharpeners in various forums, and I believe the lowest score I've seen prior to this was in the 30s.
Excellent, good to know. Thanks for doing the legwork 3d Anvil. I might in fact question Burrbender's integrity- while they show some frankly incredible results with corks, carrots, etc, I feel they should stick to that, and not manipulate a well respected platform to gain more views/fake results. That feels ethically unsound to me. I'm curious as to how others feel about this, now that we know the results to be, shall we say, fishy.
Quote from: sharpening_weasel on November 14, 2022, 04:00:31 PM
...snip...
Watching their technique, I don't see any slicing going on, just a straight push cut, but this still seems suspect to me. ...snip...
I hesitate to give this more air, but... I had not looked at the video until now.
One think I can say it the speed at which they push the knife onto the test media is WAY too fast. It should be slow, deliberate. I don't know how that might affect the sampling capability of the unit, but I can say it is bogus just due to the speed. That and IF they have the media stretched really tight, lower readings are possible, but zero is silly to think real.
Rick
I have visited their website http://www.burrbenders.com and could not find such zero Bess claim there.
Non of the videos presented at the website shows zero Bess readings.
However, they show contact information and I feel it would be fair to ask them directly.
Talked with the guy- he says that the BESS scale would round down if it reads under .5. I still find this number to be troubling- he states he uses a freehanded belt system.
I was testing a knife yesterday and decided to check the effect of speed on the BESS tester.
Results, using fulcrum in both cases:
slow test (3-4 seconds): 80g
fast test (<1s): 25g
The BESS tester is a fantastic tool for improving honing technique, but only if you consistently use it the right way. Same goes for comparing the results with other sharpeners.
Hans from Schleif Junkies sells a device he invented to ensure accurate, repeatable results. It's kind of pricey, though. I can get very repeatable results using the Edge on Up recommended method. In addition, I think it helps to look straight-down on the media holder while doing the test to ensure that the blade is centered and perpendicular to the media. My "B" model measures to the nearest 5g, and I consistently get repeatable results within that 5g margin 9/10 times.
The fellow insists he's following protocols, and mentioned that he's been in correspondence with the BESS team as well. Interesting.
He's definitely NOT following the procedure recommended by Edge on Up. He doesn't use the fulcrum (which isn't critical), and he's doing the test way too fast, which is critical. I can regularly score in the 10-25g range if I do the test the way he's doing it. Valid readings would be in the 45-80g range.