My friends:  I was a bit of a knifemaker in the early 1970's, quitting in 1975 - or so it is stamped on my last blade.  I could make a pretty knife, but not a sharp one.  The whole theory was lost on me.

I moved (this was before the word "transitioned" was invented) to racing motorcycles.  My mis-spent youth was consumed with this pointless exercise, but somehow I made it profitable, and now, in retirement, my time can be partly spent back with my old love - knives.

Through the miracle of the internet and the questionable gift of YouTube, many questions have popped up into my feeble brain.  While worrying over whether my knives were "sharp enough," I stumbled onto the little - and reasonably priced EDGE on UP PT50A BESS tester that I bought through Sharpeningsupplies.com

I have never made a better knifemaking investment !

It is possible, that the continued proliferation of BESS - testing contests will draw me back into the field - since there is a STANDARD way to inexpensively measure sharpness at EVERY stage of the building, sharpening and competing regimen.

While spending too much on sharpening supplies - and we all know how much fun that it - it teases me to find that I really know NOTHING of the theory of choosing a "steel" and a "grind" with the goal of matching that seductive YouTube poster that showed - pretty convincingly to me - that he had somehow produced a near-perfect edge on his little "PT50A" that measured below 10Gg ! ......................

Help me and others by discussing which knife steel alloy would be
best for a winning blade, and at what thickness near the edge. 

Also what included angle I might be looking for on that "Killer Edge."

As the title infers, titanium and it's effect on hardness
( along with it's carbides) draws my attention.

SPYDERCO offers little - but sometimes not cheap - sources
of blades to practice sharpening with.  Although $200 per
practice blade make my arm hair stand up,
if METAMAX @ 70HRC is a winner, than
the cost doesn't seem so bad.

Your thoughts ?

This is a copy of the E LAB A & B page taken from the EOU website at edgeonup.com. The links below are not functional but they are on the E LAB page
here: https://www.edgeonup.com/Edge-Lab.htm

https://www.edgeonup.com/Edge-Lab.html

Over on blade forums there's a big thread of some guys that are doing a competition to see who can get the lowest BESS score on a blade.  I haven't really bothered to read any of it, but I thought someone here might be interested:

https://www.bladeforums.com/threads/any-...n.1781350/

Brian.

Since I saw Mike's experiment, I've always wanted to repeat it on a razor sharp knife.



The photo shows Mike’s experiment with perpendicular load on a shaving-sharp 160-BESS edge with a flat end of a hardened steel rod:
2 Kg load on a hardened 5/16" steel rod did not effect the burr-free edge of a mid-range Henkel chef's knife - the same BESS reading and unchanged optical microscopy.

We see the same strength in our rental knife of 61 BESS -




The video shows how we check that the sharpening method is right. It goes without saying that we do not subject each sharpened knife to all this checks.

The Victorinox SWIBO Chef's knife in my video is sharpened at 12 dps and shows 61 BESS before and after the 2kg impact, and this is really impressive how strong a cleanly deburred edge is.
We filmed this episode by a single long shot.
A new Gillette razor scores 50 BESS, but of course is nowhere near as strong as the knife edge.

Key to the edge longevity, to the lasting razor edge on your knife, is to clean it of all the metal deformed in grinding.

For you belt guys, I'm looking for recommendations on my final stropping/deburring.

Here is my typical progression:
1. Cubitrion II 120 grit
2. Trizact A30
3. Leather belt (smooth side) with green buffing compound

It gives a very sharp edge, but I find even with feather pressure, the green compound, while it assists it removing the burr quickly, polishes the apex of the edge. I'd like to preserve the tooth as much as possible.

I'm looking for input and discussion on options for step 3 above (or possibly adding a fourth step). Here are some I've thought about

Changing a step:
3. Use a leather belt (or other belt) loaded with CBN or diamond compound to maintain the tooth and assist in deburring without polishing action. Any suggestions on brands or micron size?
3. Use a finer or coarser buffing bar to control the rate of polishing action. Any recommendations on types? I think I am going to abandon the honing compound, personally. At least as far as tooth preservation is concerned.
3. Use a different speed SFPM for the final step so the polishing action is not occurring as rapidly. Could this reduce the effectiveness of the burr removal?

Adding a step:
+ 4. additional trailing pass on each side using a medium ceramic rod or ultra fine diamond rod. This works very well to restore tooth to the polished part of the edge. But really it is just undoing what has been done.
3/4. use scotch brite to deburr followed by plain or coarse side leather. I take it this is the approach many are using right now, and perhaps it is also the best. No compound and just use a two-belt deburr process.

I'd love to hear from those using CBN or diamond compounds for deburring and also those using scotch brite or felt belts do deburr. The SB I find gives fairly rapid burr removal. Felt I find has not produced quick or consistent removal.

hello everyone

today i have a question and i need opinions and suggestions or advice.

one of my newest knife exchange customers is a big sports complex, i supply the kitchen knives on a bi-weekly exchange and they also have 4 axe throwing bays (booths) and i have a 10 axe bi-weekly exchange also.

the problem is they charge like 24.00 per hours per person to throw my Cold Steel Competition throwing axe at a wooden target and 99% of these people have no clue on how to throw and axe (nor do i)..............this leads to many many broken wooden axe handles.  they are open from wed thru sunday and every wed i call in the morning to see how many were broken.  so in 5 days of throwing 10 axes, they break from 4 to 8 per 5 day period.

i have been using Cold Steel replacement handles (hickory from asia) and i bought some nice Tenn. hickory handles to see if they would last any better..........NO.

they decided to try a fiberglass handled axe from Kobalt to see how they hold up.  they did hold up, but they would fly all the way back at times to the person throwing...........down the river with that plan.

i have sharpened many throwing axes for other customers before this exchange came along and most used same type of wooden handled axe or many used the Estwing steel campers axe..............a bit pricy compared to the Cold Steel wooden...............not sure on the bounce back part.................but at the cost of the handle and removing and replacing the broken wooden one every 5 days has become expensive for us both.

let me know your thoughts on all of the above..............thanks

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The most comprehensive discussion I've ever read about the shaving razors - post https://bladeforums.com/threads/is-micro...s.1769466/

I've learnt that of the multiple factors dulling the razor, the main is water salts deposited when it dries.
Now after use I blow the water out of my cartridge razor with my wife's hair dryer.

I've also finally learnt the shaving razor composition and hardness:
12-13 % Cr and 0.6 % C, heat treated to around 62-3 HRC

I was impressed by how 1 short comment by Todd Simpson invalidated that complex scanning electron microscopy experiment on cutting the hair that chipped the razor.

We've developed iPhone and Android applets for sharpening knives on popular slow wet grinders.
Some of these budget grinders have advanced features absent in Tormek.

WEN BG4270 - reversible rotation
Thanks to the reversible rotational direction of the WEN, you can use our software for both the grinding and honing wheels, and get an exceptional sharpness on your knives.

video https://youtu.be/00JYFMimU18

Holzmann NTS 250PRO - variable speed
This machine attracts by variable speed. Actual grinding wheel speed is 90-160 RPM

video https://youtu.be/9axTxxa5-iE

Scheppach, all models

video https://youtu.be/ae6nRAWKuRU

Record WG250 & WG200

video https://youtu.be/e8m1VaO75Ts

Jet JSSG-10

Details on our website http://knifegrinders.com.au/11Shop.htm

Knife Grinders and Australian Knife Magazine, in conjunction with CATRA, are proposing a new and comprehensive study  of the cutting attributes of various knives.  The following is a link to the Australian Blades Forum where additional information may be found.

https://www.australianbladeforums.info/f...ine/47288-