A new level of sharpness achieved!

[KnifeGrinders]

Today we celebrate a breakthrough in our sharpening at Knife Grinders.

Having improved our sharpening protocols based on SEM data studies,
we now steadily get the same or better edge sharpness as the Feather DE safety razors.

For quality mainstream steel, from Global and up, the edge sharpness is 20-35 BESS or near 0.05 micron edge apex width.
For premium high-end steel,  the edge sharpness is 15-20 BESS i. e. under 0.05 micron edge apex width.
Note that the Gillette DE razor has 0.1 micron edge and scores 50 BESS.

This level of sharpness is extraordinary for knives, and is more readily achieved by dedicated straight razor sharpeners.

An edge that sharp easily passes the top hanging hair tests, and the Tally-Ho cigarette rolling paper held horizontally push-cut test.

We can't tell you all details of our new sharpening protocol, but we've published the general description here:
Scanning Electron Microscope images for our sharpening protocols

Pictured is the first high-end knife Survive Knives GSO 4.1 in CPM20CV sharpened at 24 degrees included, using the new protocol.
CPM-20CV is Latrobe version of Bohler-Uddeholm M390
This knife scored 15-20 BESS i.e. is sharper than the best Feather razor, and the Feather razors are the best of all DE safety razors.




Up to this day we used to add a band-aid with the company logo returning knives to the customer as a marketing gimmick.
Now I am thinking of adding a prosthetic finger

[Rupert Lucius]

Congratulations!!!

You have taken sharpening into uncharted waters?

Rupert

[wadebevan]

Wow... scary edge, but very cool!

[KnifeGrinders]

Thank you, but "scary sharp" by our classification is just 100 BESS or 0.2 micron edge
http://bessex.com/forum/showthread.php?t...94#pid1594

This edge is utterly insane, it is so sharp that should be made illegal

[EOU]

Amazing results KG! Rupert's "uncharted waters" comment is certainly appropriate from our sharpening experience and perspective. One of these times it would be interesting to examine all the factors that  contribute to these low BESS scores. Thank the Lord that we introduced the PT50 electronic series and the "C" scale. These results would represent some pretty serious negative numbers with the KN100 and the "A" scale.

[KnifeGrinders]

Amazing results KG! Rupert's "uncharted waters" comment is certainly appropriate from our sharpening experience and perspective. One of these times it would be interesting to examine all the factors that  contribute to these low BESS scores. Thank the Lord that we introduced the PT50 electronic series and the "C" scale. These results would represent some pretty serious negative numbers with the KN100 and the "A" scale.

Ha-ha. Appreciate your humour, Mike.
That has become possible only thanks to your testers and our computer software.

For CBN (or diamond) wheels, the crucial discovery was to hone on paper wheels at 0.1 degree less. E.g. an edge set on a CBN wheel grit #1000 at 15 degrees per side, is honed at 14.9 degrees.
To set a paper wheel with such precision would not be possible without our software.
This refines the edge not touching the very apex that is already 0.1 micron after the grit #1000 as shown by SEM.
Thanks to that, even the Grepper's beloved toothiness is preserved.

The remnants of the microburr are then removed by honing at the exact edge angle (15 degrees in our example) on a paper wheel with the finest diamonds 0.25/0.5 micron, and USB microscope shows the toothiness is all there, which is to advantage for knives.

At this step edges of all knives I've done by this method score about 50 BESS, telling me that we cleanly exposed that 0.1 micron edge that already was there, even before the paper wheels.
This is a true razor sharpness, as we know.

The final step takes them to the sharper than razors level, but I'll keep it secret for the sake of my business.

[Mark Reich]

Hi KnifeGrinders,

I'm sorry I haven't been writing to you nearly as much as I've been reading everything you write. I'm very grateful for your presence on this forum!

It's stunning that you are able to achieve such low Bess scores on knives at 15°/side! I have a hard time comprehending how that's possible. Please, with sugar and spice, divulge the finishing step. We promise not to tell. 

I do have much  finer diamond compound though. In fact, I can send you a bottle of .025 PDP (yes, 10-20x finer, poly diamond, for a nice, toothy, 640,000-ish grit edge).  

Just teach me how to sharpen. Apparently I'm doing something horribly wrong. My knives haven't gotten below single digits on my old school KN100 (by old school freehand... because I'm old).

I may have to break out the Edge-Pro....  

[KnifeGrinders]

Hi Mark,

I must say without false modesty - YES, it is stunning , bearing in mind that now I get that sharp edge practically at a volume sharpening speed.

By following what I wrote above, anyone will certainly be able to get edge sharpness at the true razor level, 50 BESS or 0.1 micron edge on his knife.
Last week I sharpened a few dozens of kitchen knives using this protocol, omitting for them that final secret step that takes the edge from razor sharp to sharper than razor, and have been getting steadily 50-55 BESS - the same sharpness as a Gillette DE razor, unless the steel was a blatant junk.

What you will need:
- A grit #1000 CBN grinding wheel. We buy them from https://woodturnerswonders.com
With grossly dull knives, you can shape bevel on a regular aluminium oxide or silicon carbide coarse wheel, then continue on the #1000 CBN.

- Our software for setting grinding angle on Tormek or other model of the slow wet grinder, we have applets for Scheppach 2000, Jet JSSG-10, Record WG250 - if you own a different model, let me know, and I will reprogram the applet for it.

- Two slotted paper wheels for advanced honing, the Controlled-angle Support for Paper Wheels, and our software for setting honing angle on the paper wheels.
Overseas posting cost of $60 for our Controlled-angle Support for Paper Wheels makes it prohibitive for many, but you can make one yourself similar to what you see on our website. You will then tell me measurements of your self-made support, and I will reprogram the applet for it.

Of all paper wheels in the market, the Razor Sharp Edgemaking System are way better made - they are denser, perfectly round and balanced, smooth, fray less, and last.
Size of the paper wheel must match the size of your grinding wheel, i.e. 10" PW for the 10" grinding wheel, or 8" PW for 8" grinding wheel.

A BESS PT50B edge sharpness tester will also be needed if you work with high-end steel and hard alloys, to determine which diamond paste gives better results, and how many passes on the paper wheel with coarser diamonds you have to make, before finishing on the fine paper wheel.

Many treat paper wheels as a budget sharpening option, we found it the best advanced honing option.

If you decide to go this path, feel free to ask me for particulars when your paper wheels setup is ready.

The last bit of the sharpening protocol that takes the knife edge from the razor sharp to the sharper than razor will get in the public domain only over my dead body for the sake of my business, as it makes us unique. For that difference, I have high-end knife owners lining up here in Australia for our sharpening.

I appreciate your offer of the .025 PDP, but our tests haven't shown any advantage from using abrasives finer than 0.25 micron in our sharpening protocols - I can't comprehend why, but know it for a fact.

[Rupert Lucius]

KnifeGrinder -

Sir

Thank you for developing the software,  for me it is a charm.  Tormek should ship (your software) with every machine that is going to be used as a straight edge knife sharpener...

In ref to edge retention with your "new level of sharpness"?  Have you taken time to do any testing?  If yes, are you ready to share info?

Hope you and others will design an edge retention tester.  Seriously now that we have EdgeOnUp edge sharpness testing tools - let us fast forward to edge retention.  Manila hemp rope could be considered?  I, do not want to stand at a cutting table all day cutting rope - lets mechanize the process.

Rupert

[KnifeGrinders]

Sir Rupert, do you know what a conflict of interest is?

Edge retention is that for a professional sharpener.
Sharpness sells the service, but good edge retention reduces the service volume.

On a serious note, recently I discovered for myself http://www.cliffstamp.com/knives - heaps there on edge retention.
Just started reading through his articles, but already see that he advocates microbevelling for edge retention.

And don't forget the cutting board!
My quick test on the PT50 shows that 20 slices on a plastic, glass, marble and bamboo cutting boards reduce sharpness by 3 times, e.g. from 90 BESS to 270 BESS.

Of all plastic cutting boards, only the Japanese polyvinyl acetate Yoshihiro Hi-Soft cutting board doesn't dull the edge, but it costs a little fortune.
A good end grain wooden cutting board is the best, I recommend Acacia here in Australia.