BESS sharpness testing-any users?

[Delphonic]

The idea of quantifying sharpness has obvious appeal. As was famously said by Peter Drucker, “What gets measured gets managed,” or, here, gets better managed... better than one can achieve shaving arm hair and seeing if you can cut phone book paper. So, in principle, measurement/qualification has obvious advantages.

That said, so far as I can tell, the device only measures sharpness at one minuscule point along the edge. Obviously we’re all striving for fairly minimal variation in the sharpness along a given edge, but who knows if you’ve got it. The BESS isn’t obviously helpful there.

Does anybody on here use these devices? What’s are people’s thoughts about them? Is there any reason to doubt their utility to the sharpening community?

[gladius]

While the test can be administered free, it is novel and practically of little usefulness IMO. It is amazing how sensitive our hands and fingers are and can "measure" sharpness. With experience one can get a feel (literally) for what is sharp (~BESS-C 50-350 range). A BESS test can confirm what you already know and may be useful to gauge where your skill is.

[Delphonic]

Thanks, gladius. Where is it free to run the test? My understanding is that one buys one of their units and then tests with it.

[Radar53]

While the test can be administered free, it is novel and practically of little usefulness IMO. It is amazing how sensitive our hands and fingers are and can "measure" sharpness. With experience one can get a feel (literally) for what is sharp (~BESS-C 50-350 range). A BESS test can confirm what you already know and may be useful to gauge where your skill is.

I didn't know the details above, but I'm with Gladius here.

Accepting that the Bess test only provide a reading for an very small part of a complete edge, there are a couple of things that I've never been quite clear about.

1) If you thinned the living daylights out of blade road & edge, and then put a ridiculously acute angle on that edge as well, finished off with with a very fine stone & strop combo and did a Bess test, I'm guessing that it would give a really low number as a result (assuming as always that this work is well and competently done). But I'm not sure what the Bess reading would tell me, because the first use on anything meaningful would probably just destroy that edge.

2) The other thing is comparing two edges sharpened using the same methods but finished with say a 1k stone vs an 8k stone?

So if I get a result of a 75 Bess reading, how, in real world terms, can that be compared to someone else, thousands of miles away, with a knife at a 75 Bess reading? It just doesn't seem to provide any context. It seems similar to saying something like my mobile phone has a 10 square inch screen. Yep that's cool, but can it make calls from my house? Will it do texts? Does it store contact's details? etc etc

Interested to learn more here

[gladius]

Thanks, gladius. Where is it free to run the test? My understanding is that one buys one of their units and then tests with it.

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ref. https://hubpages.com/education/So-Whats ... ness-Scale (article by the creator himself)

BESS is administered by BESSU a non-profit organization which establishes standards and protocols for test media and instrumentation. Use of the BESS is free.

[gladius]

Accepting that the Bess test only provide a reading for an very small part of a complete edge, there are a couple of things that I've never been quite clear about.

1) If you thinned the living daylights out of blade road & edge, and then put a ridiculously acute angle on that edge as well, finished off with with a very fine stone & strop combo and did a Bess test, I'm guessing that it would give a really low number as a result (assuming as always that this work is well and competently done). But I'm not sure what the Bess reading would tell me, because the first use on anything meaningful would probably just destroy that edge.

2) The other thing is comparing two edges sharpened using the same methods but finished with say a 1k stone vs an 8k stone?

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There are other factors including steel and forging: some steel is very clean and if properly heat treated will produce very fine grain structure and thus fine edges.

[Radar53]

Hi gladius. I'm with your original statement here ie "While the test can be administered free, it is novel and practically of little usefulness IMO." In engineering terms it provides a single data point, rather than information eg my horse is 18 hands tall.

[Delphonic]

I can absolutely see the serious qualifications needed to make BESS actually helpful. But it seems potentially quite useful—with the caveat that we’d have to know a lot of details, as Grant’s excellent hypothetical illustrates. Those other things Grant cites, however, are mostly susceptible to quantification— average grit particle-size, grit material, grit hardness; edge angles.

[ken123]

A good friend of mine is an avid user of the Bess system - Mark Reich. I would recommend contacting him for a great deal more detail.

Ken

[Jason B.]

I have the original testing unit and my conclusion was... the test was for a much less skilled sharpener.

My machine edges were in the 30's and 40's while my hand edges beyond 4k would rank a 0. You could also greatly change the test outcome with varying edge finish, polish and stropping techniques.

[Delphonic]

0, 30s and 40s? That sounds like a malfunctioning tester. I think actual double edged shaving razors clock around 50s BESS when new, and those are paper-thin blades, let alone edges. I’m not an expert, but from what I’ve read those numbers seem much too low.

[ken123]

A good friend of mine is an avid user of the Bess system - Mark Reich. I would recommend contacting him for a great deal more detail.

Ken

He is a moderator on the Bess forum.

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Ken

[Jason B.]

0, 30s and 40s? That sounds like a malfunctioning tester. I think actual double edged shaving razors clock around 50s BESS when new, and those are paper-thin blades, let alone edges. I’m not an expert, but from what I’ve read those numbers seem much too low.

I was selected as a tester for the original machine and it was not a malfunction. IMO, the sharpness scale is not accurate to true sharpness.

Here is a Copy and paste of the test results I posted over on BF years ago.

Test knife, Spyderco Mule team CPM-M4, edge angle around 30 inclusive with a .020 behind the bevel thickness.

Each edge finish was tested 3 times and averaged.

Coarse DMT
1st-27.4
2nd-28.6
3rd-26.1
Average-27.36

Fine DMT
1st-9.1
2nd-9.1
3rd-10.9
Average-9.7

EFine DMT
1st-5.8
2nd-13.1
3rd-16.0
Average-11.6

EEFine DMT
1st-16.8
2nd-15.9
3rd-17.6
Average-16.7

[salemj]

0, 30s and 40s? That sounds like a malfunctioning tester. I think actual double edged shaving razors clock around 50s BESS when new, and those are paper-thin blades, let alone edges. I’m not an expert, but from what I’ve read those numbers seem much too low.

I was selected as a tester for the original machine and it was not a malfunction. IMO, the sharpness scale is not accurate to true sharpness.

Here is a Copy and paste of the test results I posted over on BF years ago.

Test knife, Spyderco Mule team CPM-M4, edge angle around 30 inclusive with a .020 behind the bevel thickness.

Each edge finish was tested 3 times and averaged.

Coarse DMT
1st-27.4
2nd-28.6
3rd-26.1
Average-27.36

Fine DMT
1st-9.1
2nd-9.1
3rd-10.9
Average-9.7

EFine DMT
1st-5.8
2nd-13.1
3rd-16.0
Average-11.6

EEFine DMT
1st-16.8
2nd-15.9
3rd-17.6
Average-16.7

I certainly believe it. I did just a little looking around on this yesterday and found a video of someone achieving similar numbers with a folder promoted by the founder of BESS himself. I'm not sure what the filaments are made of, but the number of variables seems to allow for very low numbers once you get to know the machine. That said, it seems like an interesting way to test and motivate one's self to improve using some kind of standard metric.

FYI, in the video, I noticed that the guy actually balanced the tip of the knife on another object in order to apply the smallest amount of pressure as slowly and precisely as possible. In a different video, someone else also talked about how the application of pressure was essential to getting consistent readings, and that applying pressures in different ways could vary readings by up to 100 grams. My guess is that this relevant to Delphonic's comment above. It is also worth noting that - for the vast majority of cases (including straight razors) - people sharpening at home can achieve a better edge. While it may not apply to folders, many kitchen knives shipped in boxes and sleeves that go through the post need at least a minor strop just to avoid the imperfections of being tossed around in the mail to get back to whatever their edge was shipped at, at least when one is talking about this level of refinement.

[Jason B.]

0, 30s and 40s? That sounds like a malfunctioning tester. I think actual double edged shaving razors clock around 50s BESS when new, and those are paper-thin blades, let alone edges. I’m not an expert, but from what I’ve read those numbers seem much too low.

I was selected as a tester for the original machine and it was not a malfunction. IMO, the sharpness scale is not accurate to true sharpness.

Here is a Copy and paste of the test results I posted over on BF years ago.

Test knife, Spyderco Mule team CPM-M4, edge angle around 30 inclusive with a .020 behind the bevel thickness.

Each edge finish was tested 3 times and averaged.

Coarse DMT
1st-27.4
2nd-28.6
3rd-26.1
Average-27.36

Fine DMT
1st-9.1
2nd-9.1
3rd-10.9
Average-9.7

EFine DMT
1st-5.8
2nd-13.1
3rd-16.0
Average-11.6

EEFine DMT
1st-16.8
2nd-15.9
3rd-17.6
Average-16.7

I certainly believe it. I did just a little looking around on this yesterday and found a video of someone achieving similar numbers with a folder promoted by the founder of BESS himself. I'm not sure what the filaments are made of, but the number of variables seems to allow for very low numbers once you get to know the machine. That said, it seems like an interesting way to test and motivate one's self to improve using some kind of standard metric.

FYI, in the video, I noticed that the guy actually balanced the tip of the knife on another object in order to apply the smallest amount of pressure as slowly and precisely as possible. In a different video, someone else also talked about how the application of pressure was essential to getting consistent readings, and that applying pressures in different ways could vary readings by up to 100 grams. My guess is that this relevant to Delphonic's comment above. It is also worth noting that - for the vast majority of cases (including straight razors) - people sharpening at home can achieve a better edge. While it may not apply to folders, many kitchen knives shipped in boxes and sleeves that go through the post need at least a minor strop just to avoid the imperfections of being tossed around in the mail to get back to whatever their edge was shipped at, at least when one is talking about this level of refinement.

Yes, lots of variables and like I mentioned their scale is WAY off IMO. I think if the scale went from 0-100 it would be a little better and it could reduce some variables but the test media itself was not the best. First problem was it needed to be tensioned between two fixed points and not enough or too much tension and the test was void. The next issue I found was the test media binding on the cutting edge, like trying to cut a board in half without support. The object being cut starts to pinch the object doing the cutting and again flaws the test.

It's why I said it was a test for a much less skilled sharpener. It might help someone having trouble getting consistently sharp edges but for most of us its just another test to pass and tool to find flaws in.

[Jason B.]

And FYI, I still have the original testing unit if anyone wants to give it a go. Message me if interested, wouldn't be the first time I sent it out to a forum member.

[ken123]

As a disclaimer, even though I did get a unit, I have just not had the time to experiment with it so I have no bias regarding the device. I'm inherently skeptical of any of the sharpness testing devices and accept that they will be of limited utility, but may have some value on a comparative basis.

Being the scientific nerd I am (admittedly), there is a typo. The coarse DMT grit average should be expressed as a single decimal point of accuracy, i.e. 27.4 rather than 27.36. The extra decimal point of 'accuracy' is superfluous. Doesn't affect the conclusions

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Ken