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That sounds really promising. Judging from your BESS scores, you probably do a lot more after you first hone on the leather wheel, don't you ?

Not sure what you mean here. After the honing process I usually strop on a horizontal cow leather. Can't buy kangaroo strops here in NZ, much to my displeasure. But you notice I never stropped the carver at all, and the results were outstanding.
Which raises the question is it even necessary? Let the USC do the work!

If that's not asking too much, do you think you could :
- Try this method after just SG grinding + leather wheel/PA 70 honing, and see how BESS scores are affected ?

Um, that's exactly what I did.
I was aiming for the best possible grind and hone i could do, and so for the first time ever I hones on the front jig holder and took extra care to adjust the angle in small increments to break off the burr as carefully as possible. I think that also will become standard practice in future for me.
I only use the standard leather wheel with the Tormek paste, but I'm keen to get another fresh wheel and try the Veritas Chromium oxide paste. This is what Dr Verdim recommends. 

- Tell us what you find in the bath with a knife that would have been cleaned in the US bath before being ground (and rinsed as well as possible under running water after honing) ? It would be interesting to get a good look at metal particles left inside the bath...

Agreed that would be interesting, but simple logic indicates that I would find metal particles of broken off burr.
I will add that I added some washing machine powder to the bath to aid cleaning and that may or may not have had an effect.
I'll report back after I empty the water some time today.

Okay, so my new BESS tester arrived this morning, and I put it to the test.
I resharpened two knives:
A Sheffield carving knife from my kitchen and I redid the fillet knife.
I was so eager to try my new BESS, I forgot to strop the carving knife entirely,but still got the following results:
BESS scores before: 80, and 84.
After a 10 min sonic bath: 54, and 45.

The filleter before, (but after stropping): 76.
After a 10 min sonic bath: 69.

No proof, but I reckon the sonic bath would also enhance edge retention.
I'm not a scientist, but guys, that has to be convincing evidence doesn't it?

So, anybody know of any scientist or metallurgist who could do some lab tests, and verify the theory.

I'm certainly adding the procedure to my work flow.

Incidentally, my cleaner is a commercial, 50 HZ, 40 KHZ, twin transducer model imported from China, and sold here locally.   


                 

Guys, I've just done tests on two more knives.
Another fillet knife before ultrasonic did a 100 BESS, after 10 mins in 60 degree C sonic bath scored 75 BESS.
A Spyderco Smock gave exactly the same scores.

I have ordered another BESS tester - this time the A model with 1 gram resolution, and will get more accurate data when it arrives.
It looks to me that a sonic cleaner is indeed capable of lowering BESS scores by at least a few points anyway.
Any other sharpeners out there that own quality, ultra sonic cleaners, please do some experiments to verify if this claim has merit or not.
 

Welcome to the forum, Max, and happy birthday!

You put forth an interesting idea. I admit that I know nothing about ultrasonic cleaning; however, the idea sounds intriguing. I hope you will explore it more fully and please keep us posted.

Ken

Cheers Ken, I'll certainly do that. Next batch of knives that come in, I'll do before and after tests to see if this is a game changer or not. I'm very excited about this, why did nobody try this year's ago. Seems so logical to me. What a tragedy the good Doctor isn't here to comment.

Hi Guys, Max here from Auckland, NZ, new to the forum, and just upgraded to a T-8.
I think I might have just discovered a eureka moment:

I use a sonic cleaner for dirty knives before processing, and after finishing a mid range filleter, I did a BESS test and it scored a 50, (I only have the chef version), so I was very pleased with that.
Then I thought, I've read Vadim's book and watched all his videos, and no matter what you do there will always be a residual root burr left after the final strop. So I put the finished knife, blade first, in the sonic cleaner for about ten minutes and tested it again. Low and behold the score was 25!

When you think about it, root burrs are microscopic, and sonic cavitation works on the same scale. It is a powerful shock force that could easily knock any loose remaining burr clean off the edge.
Am I the first one in the history of the world to discover this?
Please tell me I am...it's my birthday today and that would make my day.