Calling Larrin

[Freediver]

Light the Larrin-Signal. I imagine it’s the pair of
glasses in his logo on the night sky.

Haha I love it, nicely done!

[Bolster]

This happens with stone too. Unmodified flakes at the time they are knapped are at their sharpest (period). Easy to recognize if you are flint knapper and I can personally attest to this phenomena - that and flint knapping is one of the first bloodsports - bandaids are you friend.

All that said and using an obsidian edge as the best example, it’s so thin (down to 3 nanometers) you are at the molecular level - a DNA strand is 2.5 nanometers by comparison. As it was explained to me, the edge is almost liquid like in that the particles of a super thin edge immediately start settling and making it less thin, therefore not as sharp.

Would think it would be to a similar, albeit lessser, extent the same with metal knives (in addition to oxidation).

Fascinating post! Had you thought of starting a thread (perhaps in the off topic section) on flint knapping? I bet a lot of us are keen to tune in...I know I am!

[Christian Noble]

This happens with stone too. Unmodified flakes at the time they are knapped are at their sharpest (period). Easy to recognize if you are flint knapper and I can personally attest to this phenomena

Whaaaat? Do you make stone tools? WAY cool! If you wouldn't mind posting a few pics, I'm sure we'd all like to see.

Here is a pic for fun with a few bird points and an atlatla size point I made. Knife is a Rob Simonich Bitterroot in Talonite.




I believe this will be a more practical picture however, note how a hafted stone knife edge is pretty much serrated. Something like Otzi, the 5,300 year old iceman https://www.iceman.it/en/equipment/, carried as an EDC. While the hafted-knife would certainly cut, its not a slicer; most primitives, if they need to skin an animal or a precise cut, would use a freshly made stone flake if available.



Here is a video I made a longtime ago, I am sure they are much better versions now. Being knife folks here, the video shows an expedient way to make a stone cutting tool - nice to know if you are caught without your Spyderco. Basically you want rock with high glass content (volcanic) if possible; by gently banging some rocks together and listening you will start to get a sense of it, the higher the pitch the better as more glass content. Once you find your rock you could smash against other rocks with less glass content (hammer stone). The hammer stone can be in your hand or on the ground, either way you should end up with some sharp edges (obviously be super careful with your eyes). OR with a little knowledge you can make something more useful (see video). FYI, if I was doing this with obsidian or good basalt, etc. I wouldn’t have been running my fingers over those edges like I did with these. Obsidian 10x sharper than a razor.

[Manifestgtr]

I’ll toss this over here as well, since it’s becoming a more robust discussion.

Went through a normal sharpening routine with the k390 delica. I’m going to put it away for the initial period of a month and see how the edge performs then.

[Sonorum]

I have brought this up several times. The high carbon tool steals will feel less sharp after a week where I live with no use. I now put Chapstick on the edges and sometimes the whole blade and put them in Ziploc bags.

I found that putting them in carbonite works.

All jokes aside, I've experienced edge degradation without use too. Too many people saying the same thing irrespective of one another seems to point to edge gremlins or something equivalent.

[Fireman]

I have brought this up several times. The high carbon tool steals will feel less sharp after a week where I live with no use. I now put Chapstick on the edges and sometimes the whole blade and put them in Ziploc bags.

I found that putting them in carbonite works.

All jokes aside, I've experienced edge degradation without use too. Too many people saying the same thing irrespective of one another seems to point to edge gremlins or something equivalent.

I find that Edge gremlins prefer a diet of higher carbon/carbides than stainless

[Fireman]

Amazing thread. Again. Yet as usual around here. I knew knapped obsidian was sharp, but that's another level of sharp.

I have heard that obsidian can be the sharpest because the edge can theoretically be an atom wide.

[standy99]

I had this phenomenon when I was a butcher. Would always come back from holidays with my knives blunt. Worked out a few years later it was my boss who would use my knives whilst I was away. Boys at work said he grabbed them the minute I left.
“Rare he gets to use such sharp knives”

Funny as he used to buy a knife every time the knife rep came around. Just loved the sharp out of the box feel.

It was weird as you rarely talked sharpening and never sharpened someone else’s knives. It was taboo to touch someone else’s knives actually. You did have your occasional edge guru and chat but rare. No internet and forums in those days like here.

[Fireman]

Get a knife and clean all oils off of it after sharpening, then keep the tip submerged in oil, the middle exposed to air and the back end covered in chapstick to see which does best with the exposed area as the control

[standy99]

Get a knife and clean all oils off of it after sharpening, then keep the tip submerged in oil, the middle exposed to air and the back end covered in chapstick to see which does best with the exposed area as the control

Or just run it over a steel a few times after it has sat for a while

[Sonorum]

Amazing thread. Again. Yet as usual around here. I knew knapped obsidian was sharp, but that's another level of sharp.

I have heard that obsidian can be the sharpest because the edge can theoretically be an atom wide.

But if the edge is, to quote Sal, a ghost, what does that make an atom?

[Sonorum]

Very cool video!

[WyoJon]

That subject has come up several times over the last couple decades but no one has pinned it down. Corrosion, steel "relaxing", and burrs are brought up amongst other theories . Some argue it doesn't happen at all.

The edge testers are available now and we are closer to finding out if it really exists. After that then on to the why. Aside from the obvious ones anyways.

It is funny, because without equipment, it is hard to pin down "This knife is not a sharp as it was when i sharpened it 3 months ago." It does keep coming up so maybe there is something to it. I know I have had that feeling with S30V, especially when I carry it but don't use it for a period. Did the edge just rub something in my pocket, did I cut a few things with it I forgot about, did I just remember it being sharper than it was or can some steels dull with little or no use over time.

If you set a standard for sharpness it is easy to tell. My standard is i buy one brand of rolling papers that are so thin I can read through them. Hold them in one corner, and slice down through them at the other corner. If they do that without buckling the paper, i know it is sharp. Easy way to find chips in edges as well.

As for the getting dull part, i coat all my edges in ballistol after sharpening and have not had the issue. I also live at 6,500 feet of altitude, and spend most of my free time 9,000-13,000 feet. maybe that affects it somehow.

[WilliamMunny]

Was just reading some of Larrin's stuff and found the follownig:

"Corrosion is not just about cosmetics and rusting, however, but can also affect edge performance. I did a test with knives in 440A (stainless), D2 (high alloy steel with some corrosion resistance), and 1095 (no corrosion resistance). I dipped each in lemon juice and left in open air and tested after 30, 100, and 300 minutes, dipping in lemon juice again each time. There was significant sharpness loss with 1095, almost none with 440A, and D2 was in between."

https://knifesteelnerds.com/2021/10/19/ ... esistance/

So not talking minutes and lemon juice, but talking weeks and humid air might have the same effect.

[JRinFL]

Rust really only needs 3 things: Moisture, oxygen, and heat. Various chemical processes can speed up or retard rust, but keeping moisture and heat down will go a long way to preventing rust on simple steels. Just keeping your knives in a cool, dry location can help maintain the steel.

[Josh Crutchley]

Rust really only needs 3 things: Moisture, oxygen, and heat. Various chemical processes can speed up or retard rust, but keeping moisture and heat down will go a long way to preventing rust on simple steels. Just keeping your knives in a cool, dry location can help maintain the steel.

Does it really need heat? Should just need iron, oxygen, and moisture.

[Fireman]

I noticed the edge gremlins enjoy K390, I will sharpen my Endura and do a chapstick test with half the blade

[legOFwhat?]

I'm pretty sure every night, knives teleport from sock drawers to Australia to cut up rope for youtube videos, then teleport back dulled before you wake up. These Australian, space warping gremlins are drawn to the sounds of high vanadium and carbon scraping against diamonds.

Be ye so warned! They are upsidedown and sneaky

[Fireman]

I'm pretty sure every night, knives teleport from sock drawers to Australia to cut up rope for youtube videos, then teleport back dulled before you wake up. These Australian, space warping gremlins are drawn to the sounds of high vanadium and carbon scraping against diamonds.

Be ye so warned! They are upsidedown and sneaky

They can only do this because they are a half day in the future

[JRinFL]

Rust really only needs 3 things: Moisture, oxygen, and heat. Various chemical processes can speed up or retard rust, but keeping moisture and heat down will go a long way to preventing rust on simple steels. Just keeping your knives in a cool, dry location can help maintain the steel.

Does it really need heat? Should just need iron, oxygen, and moisture.

In the purest sense yes, you are correct. Heat greatly speeds the process and can be the difference between slow, controllable oxidation and rapid destructive oxidation. Cool air holds less moisture, as we know, which is why I don’t keep my good tools out in the hot, humid garage.