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BESS scores and sharpening path

Started by austijp, May 04, 2023, 04:14:34 AM

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austijp

Hi all,

I'm getting close to retirement and I'm trying to put some things in place to help keep me busy and engaged.  I recently picked up a Tormek T8.  My sharpening process is this:  For reshaping I use a 200 grit CBN but for typical sharpening I use a 600 grit and a 1000 grit.  After the grinding I use 2 steps on the leather wheels, the 1st wheel has the Tormek paste and the final wheel has a 1 mic paste.  After that process I finish with a 1 x 30 felt belt with .5 mic diamond spray. I also fabricated a FVB for the honing side, this helped me in a big way.  My BESS scores are not sub 100 like I see some people getting.  My 17.5 deg edges typically run around 150 and my 15 deg edges around 115.  My question is this, should I feel ethical charging for these types of numbers?  Today I sharpen everything I can get my hands on, my family, friends and colleagues have all provided knives for me to practice on.  They all say they are great but I'm skeptical since they are friends and family.  Do you think I've arrived at a place where I can feel ethical charging for my services?

Best Regards,
Jeff

3D Anvil

I think your edges are probably better than 90% of the commercial sharpeners' out there, and they're more than good enough for the vast majority of people.  A score of 150 is sharper than most knives come out of the box.

If you haven't already, I'd suggest you try honing on diamonds first and finishing on the Tormek paste.  It's counter-intuitive, because the paste has a higher grit rating that 1 micron, but I find I get better results finishing with PA-70.

tgbto

After trying a lot of different combinations of fine/coarse grading, 1µ/.25µ diamond pastes, chromium oxide paste, etc. I'm essentially down to two combos (using the FVB for honing) when no reshaping is needed :
- Ungraded SG wheel and PA-70 paste for standard kitchen knives and 90-110 BESS for 15dps, more like 110-120 for 17.5dps.
- DF/DE and composite honing wheel for exotic alloys, around 100-110 BESS for 15dps.

I found the added fuss wasn't all that worth the (temporary) -20 BESS. Also, there's a kind of a feel that one develops after a lot of honing on how the honing step should feel, and that makes a significant difference in terms of final BESS score.

I use the SJ and diamonds when I really want a shiny, polished edge (whether it is desirable on kitchen knives is debatable), and I agree with @3DAnvil on finishing with the Tormek paste.

Your scores show your knives are sharp, so I don't see why it would be unethical to charge for those.

As a last comment, Vadim's research tends to show that initial BESS score is not such a good indicator of sharpness in the medium term. The main factor seems to be the bevel angle, that one should basically get as low as possible as long as the edge is not fragile. 15 dps is quite safe for most knives with fair quality steel, so that could be one path for improvement if your customers don't bang their knives against one another. A lower-angle initial bevel also makes for more efficient use of ceramics rods in between sharpening sessions.

John_B

Your edges are very sharp and like previously mentioned sharper than most out of the box knives. I would have no problem charging for your work. Unless someone asks they will probably not appreciate a sub 100 BESS sharpened knife. I spend time teaching people how to maintain the edge and proper use and care.
Sharpen the knife blade
Hone edge until perfection
Cut with joy and ease

Drilon

Hello Jeff, the booklet "Knife deburring" of Dr. Vadim Kraichuk (RIP) helps a lot to understand what's happening when you sharpen a knife. You can get it at Amazon.

Your BESS readings are very good in my opinion. The reason to reach under 100 BESS is, that it indicates the the root of the burr had been removed and you get a long lasting sharpness.

Best regards,
Drilon

austijp

Thank you everyone for your insights, I felt pretty good about my results but I needed some confirmation.  I'm the type of personality that loves diving as deep as I can when I take on a project or hobby.  Drilon, I just ordered Dr. Vadim's "Knife Deburring" Book, I can't wait to dive into it.

Best Regards,
Jeff

3D Anvil

There's a lot of great information in Vadim's book, but a lot of it is also very specific to the equipment he used, which may be hard to replicate.  Probably the biggest takeaway for me was that it's often beneficial to hone at a higher angle, before coming back to the exact sharpening angle.  As a general rule, the softer the steel, the higher the angle should be.

austijp

I just took a couple of my kitchen knives and increased the angle to 15 deg and honed a couple degrees higher on the 2nd step and low and behold I've finally broke 100 Bess.  I will probably still stick with 17.5 deg on most of the kitchen knives I sharpen but it's nice to see I can achieve those types of results.  My wife of course is going to raise heck with me because her knives already scare her, I'll have to coach her through it I guess.

John_B

Quote from: austijp on May 06, 2023, 08:55:21 PMI just took a couple of my kitchen knives and increased the angle to 15 deg and honed a couple degrees higher on the 2nd step and low and behold I've finally broke 100 Bess.  I will probably still stick with 17.5 deg on most of the kitchen knives I sharpen but it's nice to see I can achieve those types of results.  My wife of course is going to raise heck with me because her knives already scare her, I'll have to coach her through it I guess.

My wife has one sharp knife she is comfortable using. If she finds that it is not good for what she is doing I end up doing the cutting. I am sure she could use all the knives but it is her choice not to. I have spent some time with her, my daughter and her daughters teaching them knife skills. I have not seen anything the oldest (12 Years) will not try cutting. Her speed is gradually improving. Show her proper finger position, using a steel and washing and her comfort will increase. My kitchen knives are all sharpened at 14° and hone at 15.5°. For my own I use the leather wheel followed by a wheel change and 1µ diamond spray
Sharpen the knife blade
Hone edge until perfection
Cut with joy and ease

Sir Amwell

Vadims' book is a good way to understand that the art of achieving a sharp edge is not so much about achieving an apex ( which is relatively easy on a Tormek) but how to deburr that edge and refine it to get best possible results.
I agree with a previous post that a Bess score should be used to give an indication of whether the burr has been successfully removed. Any score under 100 will indicate this.
I have spent a lot of time trying to replicate Wootz results using his protocols with paper wheels to deburr after setting an edge with T8. The results are tenuous, despite a lot of research and use of calculators etc to try and get sub 50 Bess scores.
My thinking now is to stop chasing those low Bess scores and be very happy with sub 120 Bess however I can achieve it.
Which doesn't include all those multi step paper wheel orientated protocols advocated by Wootz ( I can't make them work).
My advice is to find a way that works for you which is repeatable and easy and not get too hung up on lowest Bess scores.

Ken S

John, even though my wife is a very good cook and quite capable with cutlery, I have done the chopping—- by choice. I like to have a hands on feel of how our kitchen knives are performing. Also, This has allowed me to add several more knives, such as nakiris and a couple hybrids to broaden my knife education.

Stig told me how when he was training his children in knife usage he always stressed safety.

Sir Amwell, I agree with you. Vadim developed a very high level of sharpening. While this is admirable, it seems overkill for everyday sharpening. A good sharpenng job with a Tormek will be sharper than a factory new knife. I think that is a good goal. With practice and study, this will gradually get even sharper. There is no substitute for experience.

Ken

austijp

I'm almost embarrassed, I've been working on this for months now and all of a sudden it seems like I've developed a knack.  I'm  thrilled with my results but I'm having a hard time understanding why it took me so long to figure it out.  If I had to teach someone I'm not sure I could, it really seems like a feel thing.  I think I could relate it to my best friends standard response "you gotta want it" I believe it's really all about staying dedicated to making improvement and not settling for mediocre results.  I'm excited to see what the next year will bring.  My biggest challenge now is getting the tip to be consistent with the rest of the blade, i'm getting closer but I always seem to get a little wider at the tip.

3D Anvil

I think getting double-digit BESS scores very much is a feel thing.  No matter how hard you try to take touch/skill out of the equation, it's always going to be a factor when you're talking about reducing the apex to a width of 0.2 microns or less.

I think that's why people, including me, struggle to get the same results that Vadim achieved, no matter how closely you try to follow his instructions.  At the end of the day, Vadim probably had tens of thousands of sharpenings under his belt, and that experience matters.

I totally relate to your experience of hitting and then breaking through plateaus -- often for no obvious reason.  I think it comes down to muscle memory.

austijp

My wife is trying to help me out, she helps at a youth camp in our area, she said she would bring me some knives from the camp kitchen.  I was expecting maybe 10 knives, instead it was a huge box full, probably 50+ knives.  They were unbelievably beat up, the practice was great but I have to admit, I got tired of the extensive grinding it took to salvage many of the knives. I ended up tossing some of them because they were beyond repair.  Of course I will welcome that kind of gift as I work to improve my process.

WIsharp

OK so I'm the new guy here on the forum. But I think it is heartwarming that you asked the question of ethics concerning charging folks for your services. I was a Barber for over 30 years and learning to maintain shears, clipper blades and straight razors was a necessary daily chore for me. I enjoy cooking and have always sharpened my own stuff so I started sharpening some of my client's stuff for the fun of it. I recently had the same ethics question when I retired and decided to sharpen for part a time gig.  Just apply yourself and keep doing what you're doing and trust me if people are not happy with your edges, they certainly will tell you. Keep in mind that you will always be your worst critic, that's a commendable trait! Good Luck!