jimmontg

I saw you commented my thread "angle grinder support". thank you my friend! I'd really appreciate if you could support me subscribing to my youtube channel about knifes, bladesmithing, balcksmithing, DIY, slingshots and survival traps, and/or share the channel to some friends of yours. that would mean a lot for me. I have other v##eos that could interest you and I will post some other v##eos on in the next future. https://www.youtube.com/user/gianluca666
take care!

I just seen a comment/question on one of my pics that you posted a few weeks ago. Tiger coral is the handle material. Fairly easy to work with, porous though, and expensive - only time I’ve used it, but I plan on using it again. Makes a nice looking handle. That knife sold fast. Thanks for the compliments. - Mark

Hife Jim
I d##n't notice the comments you made on a knife I put on 6-15. Thanks,and the first thing my wife sa## when she saw it was You d##n't line up the pins!! LOL Where are you moving to in N.M? Lee

I had typed up a whole thing yesterday, but this stup## PM system limits to 1000 characters and I wasn't in the mood to chop it up and send it in pieces like I had done previously. I'll try to be brief.
1. Flexibility has nothing to do with hardness....it is determined solely by geometry. Hardness will determine how it fails. 2. You're looking up data for D2 developed for DIES...not edged tools. DO NOT TEMPER BEFORE CRYO!!!! 3. I've seen cryo data for O1 that says 400% increase in wear resistance. NO freaking way does cryo add 400% to wear resistance. WR is built into the steel with it's chemistry. You can't change that with cryo. 4. Sub zero (dry ice) will take care of RA in most steels, but some like the super complex SS need LN2 to get full RA conversion. 5. LN2 allows some super small eta carb##e to precip upon tempering, but these carb##es aren't about wear resistance, merely added cohesion between the martensite matrix and the primary carb##es.

Part 6...
Hope you understand, I'm just trying to share knowledge. Not claiming anything. I'm no metallurgist....but I d## stay at a Hol##ay Inn Express last night.

Part 5...
With that sa##, I know it's easy for us to get used to doing it a certain way, and changing something that has been working for us is like fixing something that isn't broken. But if you find that there is no change in your end product by experimenting with different techniques...it may be the techniques aren't actually THAT important to the end product! Which is why, when something works for us, we keep doing it. I started not knowing any of it, asking questions to Kevin and Robert, 2 metallurgists, and reading the literature till my eyes bled, then used those techniques when I started making knives. They work for me, but I thought I would pass it along, anyway.

Part 4...
One other thing...you mentioned that you do a temper before cryo/sub zero. I know this has been done in the past, for strictly one reason, concern about distortion in the sub zero/cryo, and the snap temper will help that. However....why are we employing cryo/sub zero? It is to convert retained austenite that d##n't get converted to untempered martensite at room temp post quench. What does tempering do, among other things? Stabilizes retained austenite. So if you are tempering BEFORE your sub zero/cryo...you're kinda negating the whole purpose of sub zero/cryo. Sub zero/cryo should ALWAYS be part of a continuous quench. That is to say, blade is at austenitizing temp, quenched down to room temp, then immediately into the dry ice or LN2. Then brought back UP to room temp, then tempered.

Part 3...
If it is unprotected from decarb...there will be more decarb. I just don't see any good reason at all to place blades in a cold kiln...and have asked the metallurgists, and they say don't do that. Plus...what about kilns that OVERSHOOT temp when stabilizing at target temp? My kiln doesn't....its 110V and very slow to warm up (glass kiln), never overshoots but I wait anyway before inserting the blade. Guys with evenheats and paragons have often noted that the temp will overshoot big time. You want your blade in there in when it does that? Not me.

Part 2...
You may/may not know this...I asked Kevin Cashen and Robert C about the importance of a 1200 pre soak in Hypefree blades some years ago. Their answer...it is not needed in knife sized cross sections. Pre soak is to allow a thick, or complicated, piece of steel to come up to temp evenly. If the steel is heavily alloyed, as in some of the stainless and tool steels out there today, then pre soak at critical, then ramping to the high austenitizing temp is indeed important. For O1 in knives we make....not needed at all. Plus, think about it....that is excess time in the austenite range (1350+). We are after small grain, no? That is time in the austenite phase that "may" grow aus grain. Granted....steels like O1 with the Vanadium and Tungsten probably won't see much of that. But 1095 and the like? I can't imagine what that grain looks like, especially on slow ramping kilns like mine.

Jim, thanks for your input on the O1 warping thread. The comments I want to make are more directed to you, so would be derailing the thread. I think someone sa## it best....for this situation...we might have to actually BE THERE to help the guy.

Anyway...a few things I noticed and wanted to tell you...you mentioned a filet knife in D2 that was flexible. Maybe you know this already, but I just wanted to clarify for you....flexibility has absolutely nothing to do with a steel type or how hard it is. It is simply a matter of geometry. Now, with that sa##, HOW the piece will FAIL will be determined by hardness, and some extent the steel type. Looks like I have to send this message in pieces....