How to achieve less than 100 bess?

[jimon]

Hi everyone.
I've sharpening my knives last year, and I can't understand how people achieve 50-60 bess?
My knives has around 150 bess - this is my best result. Usually 160-170 bess.
I using a standard SG stone and a leather wheel - standard set. May be for this set 150 bess is maximum what I can get?
Totally, for usual use, this sharpness is completely sufficient, but how do people manage to achieve less than 100 bess?

[Ken S]

Welcome to the forum, Jimon.

This video demonstrates how to get low BESS readings using standard Tormek equipment.

https://youtu.be/UckPmizllk0?si=jb6f3UwgOOq8JTFC

Please note at just after 1:15 the targeted bevel angle setting used on the applet, 10 degrees. (10 degrees per side). What bevel angle are you using when you sharpen?

The demonstrator in this video, our late member,"wootz" (Vadim Kriachuk of Knifegrinders of Australia) was a very dedicated sharpener and researcher. He developed a very refined technique as shown in his numerous you tube videos

Personally, I would not feel comfortable using a 10° bevel.

Ken

[jimon]

Thank you Ken,

I saw this video, and my results still around 150 bess. I guess the reason of this my angle on bevel  - it is depends from knive, and usually is 13-15 degrees on bevel.

May by I will try to do 10 degrees for the experiment, and it will takes low pressure on BESS, but also want to achieve a higher sharpness without lowering the sharpening angle.

[cbwx34]

I'm not a BESS fan... but according to this post, a 13-15 dps edge should be able to achieve a lower score.

Personally, I think BESS use is subjective, and it could just as easily be something in your testing technique, as it is in the sharpening.  I'd look at other factors... like, for example, what you wrote earlier, in how it performs in actual use.

If it is in the sharpening, one thing you might try, instead of changing the sharpening angle, adjust the honing angle a bit higher, and see if makes a difference.

[RickKrung]

...snip..
This video demonstrates how to get low BESS readings using standard Tormek equipment.

https://youtu.be/UckPmizllk0?si=jb6f3UwgOOq8JTFC

Please note at just after 1:15 the targeted bevel angle setting used on the applet, 10 degrees. (10 degrees per side). What bevel angle are you using when you sharpen?

...snip...
Ken

...snip..
If it is in the sharpening, one thing you might try, instead of changing the sharpening angle, adjust the honing angle a bit higher, and see if makes a difference.

Couple things. 

1) Honing angle that I saw in that video was 12º DPS rather than 10º.  However, I do not think that what the angle is, is as relevant as the differential between grinding and honing angles, per what follows. 
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2) I definitely agree with raising the honing angle for typical home use knives (which is all that I have), based on Vadim's other work regarding techniques for deburring steels of different hardness.  While Vadim's video was intended to show what is possible with standard Tormek equipment, it appears to also reflect what I assume is the Tormek method of using the same ange for honing.  The reference video appears to have been posted in 2019, which is AFTER the fourth edition of Vadim's deburring book where he discusses the benefits of using varying honing angles for different types of steels. 
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It was demonstrative that he was able to achieve 75 BESS by using the same angle.  I am curious what he could have demonstrated if he had used an angle more specific to the type of steel being sharpened Maybe he did without saying anything about it, so maybe it wasn't relevant, but it would have been informative for him to have mentioned it (unless he did at some point that I didn't see, as I didn't watch the video from start to finish).

Rick

[John Hancock Sr]

I'm not a BESS fan... but according to this post, a 13-15 dps edge should be able to achieve a lower score.

I'm with you. There are a lot of factors that affect BESS score, including your testing technique.

Tests have shown that after a few minutes of use you typically end up at about 160 BESS so anything below this is probably acceptable. The SG-250 and leather wheel with the Tormek compound will never give you scores below 100. You need to go to the SJ-250, DE-250 and manually stropping or other diamond infused strop to get really good scores. Not to mention lower sharpening angles also lowers the BESS scores, but obviously the trade of with lower angles is more fragility.

Interestingly Bazz from Findon Sharpening has made a few videos showing him experimenting various techniques getting low scores where he uses the SJ and a manual strop charged with compound.

[jimon]

I agree. I guess it will be difficult to get lower BESS on this set (SG+honing weel)
I tried to play with the honing angles (probably on hands, not at fixed angle), but be honest, I didn't see a difference.
I think that the SG stone + leather wheel with Tormek paste giving just like my results.
And for lower BESS rates need to use felts, wool, diamond sprays, etc.

Thank you all for your comments - if anything in my process will change - I will let you know.

[jimon]

FYI

I have checked the factorys sharpening Spyderco Military 2 (CPM S110V) - 166, 175, 156 BESS in different parts of the blade.
Angle 16/18 dps.
Total angle is 34 degrees.

This factory's result looks as mine on Tormek standart kit))))

[Ken S]

I am a longtime eliever in BESS. However, I also do the chopping for our home meals. I recommend you do the same. Working regularly at your cutting board will give you invaluable "from the trenches" feedback about your knives.

Ken

PS For some reason, Wootz changed the bevel angle setting in the middle of the video.

[Sir Amwell]

Just to add my pennies worth. I think Bess scores in the range of 150 (130/140/150/160/170) indicate that the burr has not been completely removed.
Whilst I gave up chasing sub 50 Bess a long time ago I still use the tester to indicate to me that the burr has been properly dealt with. I'm happy with anything under 120 and more than happy under 100.
So I think maybe you need to pay a little more attention not just to bevel angle but honing technique. The Tormek compound on leather wheel is good for most steels but harder steels really need diamonds and a very precise honing angle to completely remove the burr.
One important thing I took from studying Wootz book on sharpening is that the secret is not just achieving a true apex on a knife edge but how to remove the burr.
That is why his book is titled as it is.

[Ken S]

Sir Amwell,

You raise some good points. Thepursuit of 50 and sub 50 BESS numbers strikes me as pursuing the Holy Grail. Lots of bragging rights with little added practical  value. I am much more interested in an edge with staying power to cut the tomato.

I do believe BESS testing is useful in testing for residual burr, more for identifying the presence of remaining burr than for the numbers themselves.

I believe the best BESS technique is focused on accuracy rather than low numbers.

Ken

[tgbto]

To me there is a world between 150 BESS and 100 BESS, and another one (maybe two) between 100 BESS and 50 BESS. I have never gotten to 50 BESS, but the standard SG/PA-70-on-leather setup gives me consistently 90-110 BESS with 15 dps, and 85-100 BESS with 12.5 dps.

150 BESS happens in a few situations that I can think of :
- Knives made out of junk (soft) steel. They can't be sharpened at an acute angle and an obtuse angle yields poor results anyway.
- Partially honed knives. There is a burr or some plastified metal left, so they have to be honed some more.
- Medium quality steel finished with chromium oxide or diamond spray on felt wheel. I could never figure for the life of me why it would degrade BESS readings, but it does, probably because of poor technique. The readings get back to 100ish if I hone them again on the leather wheel. This phenomenon doesn't happen on 63+ HRC steel.

So I wouldn't loose courage if I were you, I would try to hone a bit more than you usually do, and remember Vadim's results that low initial BESS is not a significant factor in edge retention. Steel quality and edge angle are, though. I also find that SG edges tend to retain their cutting ability longer than SJ edges.

[Ken S]

Nick,

You make some good points. Like you, I believe one of the most useful functions of BESS testing in detecting minute residual burr which needs to be removed. I've known Mike Brubacher, the "B" in BESS, for many years through email. Mike is a really nice, helpful guy.

I have thought about purchasing a PT50A because of its 1 gram accuracy. So far, I have tabled that decision. My early version of the PT50B with 5 gram accuracy is more than enough for me. In fact, the 25 gram accuracy of the PT50C will detect residual burr problems. (For a shapener thinking of buying a BESS tester, I recommend at least the B model.)

Ken

[3D Anvil]

I think it's quite possible to get a 15 dps edge to 100 BESS or lower using the SG wheel and leather wheel with PA-70.

Best to keep it simple.  We know there are two components to sharpening:

1) Apex the edge.  Can you feel a burr all long the edge after your final pass on one side, and then on the other side?  If so, the SG wheel has done its job.

2) Remove the burr.  This is the hard part when it comes to getting very low BESS scores.  You can get sub-optimal results if you:

   a. Don't remove all of the burr, which can happen if you are honing at too low an angle, or if you don't hone enough.

   b. Round the apex by honing at too high of an angle, or apply too much pressure when honing.

Freehand honing on the leather wheel is definitely something that takes some practice and muscle memory to perfect.  You can work around that by using a front vertical base to hone with a jig, or keep practicing! 

I would suggest marking the edge before you start honing so you have a better idea where the bevel is hitting.  It's also helpful to use some kind of magnification to give you a better idea what's happening. 

Lastly, I think it helps to minimize the burr as much as possible before you go to the leather wheel.  One way to do that is to do a couple very quick, very light alternating passes on the sharpening stone.

Wootz's method generally involved honing at higher angles before finishing at the sharpening angle, depending on the steel involved.

[iSharpen]

Here's how I do it and my thoughts.

First, the knife must be high quality. No point trying to achieve a 100 BESS with a Wiltshire knife. You'll need VG-10 or better. Global knives will get you there. My best BESS was a 52 on this brand new IKEA (of all things) VG-10 knife. I did have a video on the event before my original channel was taken down.

I can achieve a near 100 (or better) BESS on the standard SG wheel but I grade it using diamond plates. It's important to start rough to achieve a fresh apex so I start by dressing the SG with an 80 grit diamond plate. Then once I achieve a strong and definite burr I re-dress the wheel with a 32 grit diamond plate making sure to settle all the grain. I check with my thumb to make sure I don't feel any raised grains. Then I grind away as usual making sure I do my best work. A super acute angle isn't necessary. I achieved the 52 at 15 degrees per side as set with a (probably worn out) WM-200 so it was probably even a bit higher. I'm guessing 32 degrees total. I grind until I'm happy the entire bevel has been smoothes so probably at least 4-10 passes per side. No less than 4.

I don't use the Tormek paste though (and haven't for years). I do all my honing with green Chrome Oxide these days. I was frustrated for a long time until I realised I was pressing too hard and honing too much. I use a light touch at an increased angle than the bevel. I do all honing by hand. I first lay the knife down until it grips the wheel (signifying that I'm on the bevel) then raise it slightly so I'm only honing the apex.

I hone and check for burr by running the blade against my fingernail. I check early so I can still feel a bit of catching and only stop after all catching is gone but NO MORE! I used to continue on the strop which is made of super thin Kangaroo body leather on a wooden block but these days I hardly use the hard strop. If I can achieve a nice glide on my fingernail I stop and test on a Tally-Ho cigarette paper. If I can achieve "glidage" through the paper I know I'm at or close to 100-125.

Using this method, a super thin japanese (or chinese) knife made from good steel (VG-10 or equivalent) such as a global will achieve a very low BESS score. I think the biggest factor is not to over hone.

Hope that helps.

Note: I haven't achieved a better score or result using the SJ wheel than I've been able to achieve on a standard SG wheel graded to 960 using the Dr Vadim diamond plate method (which has been a real game changer for me). I'm a fan of the foam backed chinese 320 grit diamond plates.