BESS Sharpness Tester: Did I waste My Money?

PeteCress

PeteCress

Joined
Jan 2, 2023
Messages
16
Wanting to be able to evaluate my knife-sharpening skills, I layed out the big bucks for one of these things.

But the more I read and hear, the more I come away thinking that it was misspent money.

To wit:
  • There seem to be two types of sharpness: push sharpness and slicing sharpness.
  • The device in question measures only push sharpness.
  • In the real world, slicing sharpness is what counts.
  • On the device in question, technique plays a significant role. A quick push will give a very low (and incorrect) number while a very slow push supposedly gives a correct number.
  • Back-to-back tests on the same area of the same blade can give significantly-different results - to the point where I have taken to doing 3 measurements and averaging the numbers.

So: was it money down the drain, or am I missing something?
 
Last edited by a moderator:
I"ve always suspected that these BESS tools were not as precise as advertised. There are too many variables that need conntrol-- string tension, type of edge, imperfections in the string, how the edge lands, etc.

A number of people have started using them, but then stopped.

You may be able to create a tight protocol that increases the precision and is more repeatable, but your numbers would be good for only you.
 
I’d think If ur really trying to chart and graph measurements then it’d be good. But just to “measure” the sharpness for your own sharpening progress, it’s not necessary. If you cut mostly the same stuff day to day, then you’ll be able to tell whether your skills are improving just based on how well it cuts that stuff
 
What did you hope to use it for when you bought it?
If all you want is to know if something is "sharp" that's easy. If you want to be able to objectively answer "how sharp" then you need an objective test.
I think depending on what you are trying to do it can be a good and useful tool, but you have to know how to use it and how to interpret the results AND apply those results to what you want to achieve.

It's like asking a question on this site.
You're going to get a wide variety of responses, and you have to be discerning in interpreting and applying those answers to your situation.
 
Like others said it depends on what you purchased it for. I use mine frequently for checking sharpness for CATRA testing. I have to get below a certain value (150g in my case) to ensure consistency. The CATRA test is a slicing test but the push cut sharpening is still effective for ensuring consistent sharpening. The main thing I usually see with it is if I have effectively removed a burr which I can not always tell by feel. This usually shows up as a value above 200g. But if I was using different sharpening methods the values would be different, the edge I use for CATRA is 400 grit 15 dps and getting under 150g would be easier with high polish.

In my opinion the people talking about the effect of technique being a problem don’t understand how testing works. All tests can be “cheated” by changing variables. Often in engineering we intentionally change the variables and measure their effects. This is why there are testing standards and to compare between different test labs all variables must be the same. So just because someone can change how the test is done and affect the result doesn’t mean it isn’t a good test. That being said, there isn’t really a “test standard” for BESS testing and just because someone claims they got a 0g edge on YouTube doesn’t mean you shouldn’t question how they achieved that value. Even with the information that Edge on Up provides people don’t always read it, such as their recommendation of multiplying values in the premade clips by 1.2.
 
I don't know much about these but thought you might get something form this guy's video. Skip close to the end where he explains and uses the BESS system to judge the edges. I found it pretty informative.

Jim

 
I prefer to keep things simple. If a knife does what I need it to do that's good enough for me.
 
I like mine and find that it gives accurate and consistent results. I've been through about 4 or 5 canisters of test media. I use a 100g weight to tension the filament. It's nice to know if an edge needs more work before returning it to a customer even if you've used the same sharpening protocol for the 500th time.
 

Some info in the video needs to be verify, but it explains very well overall on what even is "sharpness".

I don't think you waste money as you want to test your skill. It is much like the hair cutting as performance bench for sharpness, like this guy want to do as a demonstration of skill

The push test is great to see how well the apex of the knife is worked on.

The effect of the blade geometry and material in this test is minimal, which the geometry is one of the biggest factor in other cutting performance test, and the angle of the blade plays more.

The result should be compared to other blades of the same angle if you want to quantify that push test sharpness. A narrow angle naturally get better result, it doesn't necessary have anything to do with skill.

The testing medium, the wire, might dull the knife a little, so even using the same spot might inevitably change the result.

Overall, I think that push is fine as a testing method for your skill. If you are not satisfied, then yeah, it is probably a waste.
 
PeteCress said:
So: was it money down the drain, or am I missing something?
Click to expand...
Only you can answer this question.

That's how it usually goes. When starting something (Hi-Fi, Photography, Videography, Woodworking, ....etc) you are eager and this thing grabs you so you think you need much more things that you really need. With time you discover you actually don't need all those things.
I personally think for home use you have enough good old ways to test how sharp is your edge:
-newspaper: cut it in direction of grains and across the grains; try push cuts 90/90 degrees across grains
-arm hair: try to shave your arm; try to tree top arm hairs
-head hair: try whittling you hair

But if you want to become a professional sharpener and you will sharpen fancy and expensive knives for demanding customers then
I suppose you will need to add a certificate with some Bess values to your sharpening work.
Otherwise I wonder how long will you use this thing.

I just checked how much one of those thing costs....not cheap indeed.
 
I have always felt that the Bess was very limited way of testing as it focuses on just one small section of the edge.

Myself I use paracord to test if I have the edge apexed, doing a push cut will show very quickly if you have. The blade will easily push through if you have but if you haven’t it will just dent the cord. Now the edge might be very sharp so that you can saw cut through which is a type of edge that you might want, but if it doesn’t push through then your apex is round like a ball point pen. The benefit of this technique is you can test different sections of your blade easily.

G2
 
I have lots and lots (and lots) of sharpening gear, and I would say that the BESS tester was the best purchase of the lot. It is without a doubt the best way to improve your technique, as it will tell you precisely how well what you're doing works. I get very consistent results by going slowly and threading the filament holder with just enough pressure to take out the slack.

But I'm a sharpening nerd, so there's that.
 
Would I be correct in assuming that the results would only be valid if comparing the results between edges sharpened at the same angle?
 
garry3 said:
Would I be correct in assuming that the results would only be valid if comparing the results between edges sharpened at the same angle?
Click to expand...
The answer is yes and no. ;)

In theory, you should be able to get a knife equally sharp at any angle. In reality, though, you're almost always going to get a sharper edge with a lower angle, just because there's more room for error. IOW, if you ever-so-slightly round the apex of a 12° edge, the falloff in sharpness is going to be much less dramatic than it would be if you slightly rounded the apex of a 25° edge.
 
Y'all keep saying BESS only tests one spot.

Well,


Test more spots.

The reality is, most everyone's edges are not the same sharpness throughout the entire edge so as far as getting some scatter in the sharpness
results everyone should seriously observe their edges with magnification and a laser goinometer if they're serious about ruling things out.

Most of you would be quite surprised seeing your edges.

Reality is different from imagination.

The problem with slicing is slicing can actually hide flaws better.

It's is a fact that slicing takes significantly less force than push cutting.

So, a slicing test may not show the true quality of the edge.
 
You must log in or register to reply here.
Back
Top