How (Not) To Cheat At BESS!

[@Skarphedin]

Intresting how the values change with the same knife and no change to the knife , but cutting cigaretpaper is a pass in my book 😅

[@greatedgeltd]

Hi Bas, good to call attention to the limitations of BESS testing. One thing to watch for - make sure your filament support is exactly centred before you start. You can test that by pressing down on the knife support - the reading should remain at 0. In a couple of your attempts in this video you’ll see that the BESS reading jumps to 9-13g when the knife touches the support, but before it’s made contact with the filament. That will certainly bring some variability to the results.

[@iSharpen]

@@greatedgeltd interesting! I've noticed that and wondered wtf. Good info. Thanks.

[@greatedgeltd]

@@iSharpen after taring I press on the pedestal. If reading remains 0 I proceed, or else adjust the filament support, tare and try again… it’s a weak point in the design IMO

[@iSharpen]

@@greatedgeltd gold.

[@BladeLabMiami]

Honestly, I would consider those results (witch the clamp) quite consistent, especially if you throw out the 112 outlier, although even that isn't far off. The edge itself isn't going to be 100% consistent. And to be really fair, you would have to do the same thing with the test clips to see how they compare. As you demonstrated, speed is a bigger factor than tension. You can cheat with the clips just as easily by chopping down on the filament.

[@iSharpen]

True, a few were similar sure but the tension variation was 50-100% off from the average. I’d consider the variation of 98-198 practically worthless. The extreme speed results aside, even at the correct slow speed I’d have to consider using the cartridge extremely unreliable bordering on scientifically worthless. I’ve used over 400 clips prior to this and their consistency is undeniable. Have you ever used the pretensioned clips?

[@BladeLabMiami]

@@iSharpen But the variance was less than 20g when you were trying to use the fixture the right way. Obviously if you're intentionally doing it the wrong way you're going to get bad results! I've never used the clips, myself. Never felt the need to because I get consistent results with the fixture, the clips are too expensive, and the fixture is actually the BESS approved method.

[@iSharpen]

@@BladeLabMiami I disagree. The difference in just the tension alone makes the results almost useless. Without a tension standard (which the clips provide) the results are too varied to be informative. The only way the cartridge can be used (at best) is “better or worse than before” but the numbers can’t be compared to another operator. The clips make the results informative and comparable between users globally but the cartridge numbers vary depending on the tension applied by each user. I’ll stick to the clips. These tests prove the numbers you get from the cartridge are only useful and relevant to the operator and only then if the tension is exactly the same for each test. But one operator’s tension will give very different numbers to another’s. But if you take one knife and the clips (and slow steady pressure and speed) it’ll give reliable and comparable numbers no matter who’s pushing. I think we should both use real world tests such as cigarette paper as the ultimate test. BESS numbers are almost irrelevant, especially if they come from the cartridge. I knew this the very first day I got the BESS tester when I did this same test. That’s why I had to bite the bullet and buy clips. But yeah, they’re expensive.

[@BladeLabMiami]

@@iSharpen I think we're going to have to agree to disagree! There is a standard for the fixture, and it's 100g of tension. Rig up a 100g weight to tension the line and Bob's your uncle. Anyway, we're really splitting hairs over small differences that won't make much practical difference after the first few cuts. Speaking of splitting hairs ... hair whittling is another excellent test. 😁

[@iSharpen]

@@BladeLabMiami I’d have to buy sone hair from somewhere. I’ve run out.

[@pauldixon6654]

The tensioner is the screw that tightens the wire/monofilament. you pull the amount you need then you screw down. wind the thread around the screw once.

[@iSharpen]

I noticed that Dr Vadim didn’t use weights at all. He just tensioned it with his fingers and screwed it down. Some have suggested I wrap the wire once around the screw. I’ll stick with clips for now.

[@nicolashuot]

Many thanks for this! I was looking where my measurement inconsistency was coming from...

[@iSharpen]

@@nicolashuot low numbers are fun but the cigarette paper never lies. Buy a few packs of Tally-Ho or Rizla Green.

[@adrianhochmann3091]

have you ever testet the difference between the sharpness a flat sharpening angel and a convex "angel" produces? with a tormek I am not experienced enough and I doubt that a convex angel would even be possible but I am curious to know with wich method the sharpness of the edge remains the longest and if there is even a difference. Do you know something about that topic?

[@iSharpen]

@@adrianhochmann3091 that’s an interesting question. If you do a search here on KZbin there is one guy who managed to get a convex grind by rocking the knife in between the two black stops on the new style knife jig. I’ve never tried it on a knife but I do some axes by hand with a convex bevel. I imagine there might be some strength advantages when slamming an edge into a piece of timber but most knives aren’t used like that except for some heavy bone crushing cleavers but I’ve never had many of those. I grind heavy cleavers at 25 degrees per side to give them strength for that activity but it’s pretty rare for me.

[@MoHarbi-k2v]

The majority agrees on using 100 grams for wire tensioning. That is how i use it and the results have been consistent. I have also tested clips and found their results to be consistent as well, although the clip numbers are lower than the 100-gram tension. I have heard that clips are tensioned up to 200 grams. It's worth noting that the BESS tester comes in three different models with varying degrees of accuracy and reading speed. Model A has an accuracy of 1 gram and a reading speed of up to 25 times per second, while Model C has an accuracy of 25 grams and a reading speed of 5 times per second. This makes comparisons between different users' devices inaccurate. Personally, I use it to compare my own data not to compare my data with others, especially after finding out that some people are cheating to get unbelievably low readings with clips what they do is heat them slightly with a lighter and then immerse them in water, which makes them brittle and gives lower readings

[@iSharpen]

@@MoHarbi-k2v that’s very interesting and yeah, I have the pro commercial grade version.

[@Phil.D333]

wow interesting

[@robertdewalt8711]

100g should be used to have proper tension on BESS C media, also important to push at slow pace to get consistent results. I have ordered 100g calibration weight to have proper tension on media. Currently using prescription bottle with small sockets. I should be receiving 100g calibration weight tomorrow afternoon.

[@iSharpen]

Yes, another commenter also made this observation. I didn't know that. I still prefer clips. I just wish they didn't cost me 60c each.

[@robertdewalt8711]

@@iSharpen. Today I received the buffalo hide today, three 12 “ by 12”. One side is smooth and one side not smooth so I will use adhesive to affix smooth side to board.

[@iSharpen]

@@robertdewalt8711excellent! You want the bumps and ridges to help dislodge that burr root. Let me know how you go.

[@2adamast]

Could also use a different wire. I made my own version with a 5$ dynamometer, works in grams but the values are probably different

[@iSharpen]

Fascinating. The only thing that matters is "was it better or worse than the previous measurement?" To be honest I prefer a real world undeniable test and that's how it glides (or not) through 17gsm Tally-Ho or Rizla green papers.

[@pauldixon6654]

@@iSharpen HI GUYS . If useing rizzla red is thick green thin blue super fine.

[@thechumpsbeendumped.7797]

@@pauldixon6654 Thanks, you taught me something today. Not being a smoker, I didn't realise there were different thicknesses in cigarette papers so I've been using the thinest ones, Rizla Blue without knowing I was making it harder for myself😂. I know if I can cut them along their length it's plenty sharp enough for me and my clients. I can usually cut across the papers but that's not as easy at the relatively obtuse angles (18-20° each side) I sharpen to most of the time.

[@thechumpsbeendumped.7797]

That sounds interesting. Please can you tell me the name of it and where you got it from? As for the values being different to Bess, that doesn't worry me as long as it's consistent and repeatable.

[@2adamast]

@@thechumpsbeendumped.7797 A 2.5N Spring Dynamometer, got it on Ali. Had before 10N model that remembers the peak value, neither is perfect. Use a loop of sewing thread on the hook as medium. In practice, I mostly push cut paper for testing (edit) I see they have 5N digital dynamometer with peak memory for 30$

[@mikeobrien4081]

I suppose someone could make a tension measurement device to press down on the filament before cutting, measuring the filament's resistance at a set amount of compression (say, compressing the device's spring 5mm).

[@iSharpen]

@@mikeobrien4081 that’s a great idea. But then you’d have to compare the cost of that compressor device to the cost of a bag of clips. I just bought 200 clips. Others love the cartridge, I don’t trust it.

[@mikeobrien4081]

@@iSharpen If I know hobby sharpeners, they'll buy the cartridge, and the cartridge tester, AND bags of clips. And three stones in a grit they already have. (Not talking about me, no sir...)

[@iSharpen]

@@mikeobrien4081 it’s a happy illness.

[@billmanning8806]

I use 100g every time to tension and also a very slow blade-lower-down. Seems consistent to me...

[@iSharpen]

Good to hear.

[@pauldixon6654]

HI Bas. when iv watched other people use the bess they as well as myself double turn around the clamp or clasp which ever as you demonstrated you pulled tight only. food for thought. I personally think its all to do with how to level the blade when puting pressure down. works for me. Hope this helps

[@iSharpen]

All input helps. What do you mean double turn? (Baz)

[@torsen1987]

The Bess sharpness testers are not accurate at all.. It's just for giving an indication.. Just like when you're measuring wetness in concrete with a device that only measures at the top..

[@iSharpen]

I'm not sure I can agree with you there. I think they are accurate in that they can be directly compared to real world items like a double edge razor and a single edge razor. I've often compared the numbers (obtained by clips) to how they slice through a 17gsm cigarette paper which is a very reliable measurement of burr root existence. The main thing they measure (in my view) is the existence of a burr root. This is important in determining real world usability of a knife because the burr root is largely responsible for early failure of an edge. So in that respect the numbers are as accurate as they need to be. They're used to eliminate the burr root. They can also be used to measure when you're "not quite there". It's also an excellent training aid which is very important for people wanting to become as good as they can at sharpening. Like me.