Can anyone help me understand the difference between the 3M Trizact 337DC and the 347FC belts?  I've done a google search and looked at 3M's info and found the following.  What should I know?  I'm in the process of buying belts for my new Viel S5 grinder (coming on Tuesday) that I'm putting on a 1/2 HP 1750/1140 rpm motor on.  Plan to run at 1140 rpm to give me 1790 sfpm belt speed to sharpen knifes.  Currently using a Ken Onion Blade attachment.  Time to join the "bigboy" party (lol) and please be kind to this newbie.


337DC
Equipment - Machines
Bench Top Motors, Manual Backstand, Pressure Assit Backstand
Flex Type
No Flex
For Use On
Aluminum, Carbon Steel, High Nickel Alloy, Soft Metals, Stainless Steel, Titanium/Zirconium
Industries
Marine, Metalworking
Micron Grade
Micron Grade, A160, A300, A45, A65


347FC
Equipment - Machines
Cylindrical Grinders, File Belt Sanders, Manual Backstand, Pressure Assit Backstand, Random Orbital Sanders
For Use On
Carbon Steel, High Nickel Alloy, Stainless Steel, Titanium/Zirconium
Industries
Metalworking
Micron Grade
Micron Grade, A160, A30, A300, A45, A65

I was sorry to learn that the knife sharpening community has lost an important influencer, prolific writer and videographer, and friend in Vadim Kraichuk, this month. Some may have known him better as "Wootz" from other forums but on Bessex, he was simply known  as the, abbreviated, "KG". Vadim was an unabashed and energetic pursuer of the science of knife sharpening.  His experiments helped sharpeners distinguish myth from reality and then, he freely shared  those findings with the knife sharpening community at large. His presence and contributions will be very much missed. Our thoughts are with his wife and children in Australia.

This looked like an informative video about Cubitron II.

https://youtu.be/KrQLMEyiN94

Krn

Hello All, I seem to have been away a while, and may not be up to speed with the latest on the SET.

I did try a couple of searches for 'Structural' and 'SET' but didn't find what I thought might be some more established threads on this (please point me at them if I missed them).

How has everyone ben getting on with their SETs? Are there any tweaks, or hints for getting clear results?

If I were to summarise my own findings I'd say the first challenge is the consistency of the testing edge. My results are showing inconsistencies which I am sure are due to the consistency of the edge from test sample to test sample.

So far I find that unless an edge exhibits chipping, I can virtually guarantee that I can strop the test area back to a sharpness either identical or often better than the starting sharpness (although usually there is a visible sign of the testing site).

It feels like the results I have so far don't quite match with expected performance, so I'm questioning the value of what I've done so far.

I've got some blades incoming where I would like to show a clear difference with the SET. With a 58HRC and 64HRC version of the same blade there should be a significant observable difference.

What is the current thinking on this?

I got two knives from a lady my wife ran into that she knows from her work.  They were both Classic Wusthoff's; a 3.5" parer and a heavy 8" chef's.  Both had their plastic handles melted from being left on a hot stove.  They were uncomfortable to hold due to sharp edges on the melted plastic.
 
I sanded the handles so they were smooth.  Not pretty, but much better with no sharp edges and are now comfortable to hold.
 
Using the Kally 1SM and a Kallyrest, after sharpening, handle to tip-
 
3.5” parer:  75, 85, 80.
8” chef’s: 70, 80, 65, 75
 
For the parer I used 150 Cubitron, very fine Scotch-Brite, rough side of leather belt no compound.
Same for the chef's except it was duller so 80 AO first to speed things up, then 150 Cubitron, Scotch-Brite, leather.

I don't use compound because I want to preserve as much "toothy" as possible.  Compound is a fine abrasive and reduces toothy.
 
Didn't take very long to do.  Then I cleaned the blades with liquid Barkeeper's Friend and polished the handles with Turtle Wax Seal and Shine Si02 ceramic spray.  I charged the lady $5.00.  A real windfall.  Now I can retire.

I received a PT50A just a few days ago, and have tested 8 knives with it so far. My best scores so far are a few of my kitchen knives, 100, 97, 98.

While I wish to improve those further, my primary issue is an 20CV folder. I have tested after sharpening 3 times and always get a score in the 150-158 range. My old CATRA goniometer shows a mildly convexed (freehand) edge around 18 dps. Over the last couple days I verified that with this edge I can clean shave arm hair in both directions, tree top arm hair against the grain, shave curls off of hair, push cut rolling paper along its length (but not on the short side), filet notebook paper, and dry shave stubble from my face with very mild skin irritation (no redness or blood weeping). After cleanly slicing notebook paper and push cutting rolling paper several times, the BESS worsened to 167. After that, I did 5 passes per side on crox followed by 10 per side on plain leather, and the score went back to 154. I have looked at the edge under a cheap pocket microscope that claims 100X magnification, and it looks pretty clean. Am I dealing with a burr? I thought the scores would get much worse after cutting if so. Is the ~10% increase in force indicative of a problem? All the references I see (primarily the knife deburring pdf I just purchased as well) say the BESS score would be much lower for the other cutting "tricks" I'm doing.

Typically, my rough grinding is done on a variety of things, diamond, SiC, etc, then 800 King or 1200 Sigma Power > 4000 King > 1.0 micron diamond on leather strop block or 13000 Sigma Power > 0.5 micron diamond on leather strop block > chromium oxide on leather strop block > plain horsebutt strop block. On the stones I generally scrub until there is a palpable burr, then do solely edge leading alternating strokes to remove. The strops are all of course edge trailing.

I have the full set of DMT diasharps from XXC to XXF, I'm thinking of using the 3 micron XXF then moving to the diamond strops. Should I expect better deburring and improved BESS scores? I don't use jigs, so I'm not sure how low a score I can get. I sharpen other knives (particularly fixed blades) around 13 dps +/- natural freehand deviation, but have kept the bevel width about the same as original on this 20CV folder.

Hi All,
I have recently teamed up with Mike at Edge-On-Up to now offer the range of testers and parts directly to Australian consumers.

We are based in Sydney 

Feel free to check out the site and let us know what you think
https://zanvak.com.au/collections/edge-on-up
-Russ

ENGLISH

The COVID-19 Coronavirus is a relatively large virus, 100 nanometers in diameter




a 100-nanometer edge scores 50 BESS, this is the apex diameter of the Gillette razor.

When your knife edge scores less than 50 BESS, its width at the very apex is less than the size of the single coronavirus.
When I realised that, I find it quite fascinating.

My last video shows a knife edge that is half the size of this virus, and what this edge can do:

I am pretty new here, and I am sure
you can tell that from my posts.......

I have recently invested - and it's my
best-ever sharpening investment - in the PT50.

After some flailing around, I was able,
with careful attention to protocols, to get
one of my little "super-steel" SPYDERCO knives
down to a (admittedly brief) lifetime best of BESS 36 !

With that under my belt, I can give more attention
to the part of sharpening that I CAN'T seem to measure:  "TOOTHY."

Sharpness as measured to BESS seems fairly
straightforward to me now, but I read folks that
DON'T measure to BESS talking about how their
"toothy" knives are better at cutting than knives "BESS" sharp.

How do we measure that ?