Nathan the Machinist
KnifeMaker / Machinist / Evil Genius
Moderator
Knifemaker / Craftsman / Service Provider
- Joined
- Feb 13, 2007
- Messages
- 15,666
Warning, wall of text. I'm feeling loquacious
I think there is some misunderstanding on what is meant by the term "Delta 3V".
Delta 3V is a low temp tweak for the heat treat of 3V, but a low temp tweak to 3V is not necessarily Delta 3V. All halibut is fish, but not all fish is halibut.
The process is not patented (it is a trade secret) and the term is not trademarked so there is nothing stopping someone from saying their steel is "Delta 3V", but unless it actually is Delta 3V, calling it such is a little disingenuous.
Running a low temp tweak on 3V without addressing the RA issue correctly doesn't necessarily work better (or even as well) as the industry standard HT, but when optimized really is a much better heat treat. I mention this because folks need to be aware there is the material condition going into HT including any thermal cycles, the times and temps (duh), quench rate, and timing of cryo, and tempers, it's not just a particular austenitizing temp and tempering temp. I think most people know this, but sometimes I see where people don't get it.
My work with 3V is based on work I did on D2 ten years ago. At the core, it attempts to address shortcomings with edge stability by avoiding the secondary hardening hump and addressing retained austenite issues. At the end of the project there is little bit more to it than that, but that is it in a nut shell.
There is not a huge difference between Delta 3V and the un-named low temper tweak we were using that immediately preceded it. They're related processes, the primary functional difference being improved edge durability with the Delta version. This difference shows up in side by side testing in rough use but I think most folks would like the immediate predecessor just fine, it was no slouch. Something similar to that predecessor is available to everybody at Peter's and it is a good HT.
A few years ago we (Dan, Guy and I) noticed an issue with the low temperature tweak with some lots of 3V. The problem boiled down to the material condition, but while investigating it we decided to fully investigate the effects of several variables on edge stability, their effect on each other, and to confirm or verify some assumptions we'd had coming into it. The end result was fine tuning several specific variables and we found that the process both worked better and was more consistent when we added a couple steps. There are a few areas where we've changed the way a few steps are done that required some changes at Peter's in order to duplicate them.
I was always open about the tweaks I was doing on D2 and 3V, but when it came time to really do the exhaustive work of fully optimizing the HT on 3V it was a time consuming and expensive collaboration with Dan, Guy and myself. I enjoy discussing these things and sharing what I've learned with this group, but at this point I am unable to discuss details because it is a propriety process shared among the three collaborators.
Folks need to keep in mind the development of tweaked 3V has been on-going for years. We finally did the formalized R&D to put-to-bed the fully optimized tweak and named it, but the previous tweaks were good tweaks. It was named Delta 3V because it was a change (Delta) to the previous process, the end result was different enough to justify noting the revision.
Two things that I would like to be clear about are: I'm not saying that only Delta 3V is a good HT, a person doing their own heat treat could very well have a very good HT. I would be surprised if a small maker has committed the time and resources to fully optimize a proprietary HT process but I'm not saying it's impossible. Even short of that, I'm sure plenty of folks have very good 3V. The house HT at Peter's is very good. But I'm also saying that unless someone is running our protocol, it isn't Delta 3V. It might be very good, I'm not arguing that, but it isn't the same thing. And I expect that most likely a person could measure a meaningful difference in controlled side-by-side testing.
If a person really does their homework and is prepared to demonstrate it to folks they should name their own process. If it is demonstrably different it deserves to be differentiated. But a person had better do their homework. This is one of those areas where, to the uninitiated it might not seem like a big deal, but I promise you that actually optimizing a complex industrial process for a particular outcome is not trivial or easy. Just setting up to make meaningful comparisons (not just some dude cutting stuff and saying "it cuts good") requires a lot of time and hard work.
I think there is some misunderstanding on what is meant by the term "Delta 3V".
Delta 3V is a low temp tweak for the heat treat of 3V, but a low temp tweak to 3V is not necessarily Delta 3V. All halibut is fish, but not all fish is halibut.
The process is not patented (it is a trade secret) and the term is not trademarked so there is nothing stopping someone from saying their steel is "Delta 3V", but unless it actually is Delta 3V, calling it such is a little disingenuous.
Running a low temp tweak on 3V without addressing the RA issue correctly doesn't necessarily work better (or even as well) as the industry standard HT, but when optimized really is a much better heat treat. I mention this because folks need to be aware there is the material condition going into HT including any thermal cycles, the times and temps (duh), quench rate, and timing of cryo, and tempers, it's not just a particular austenitizing temp and tempering temp. I think most people know this, but sometimes I see where people don't get it.
My work with 3V is based on work I did on D2 ten years ago. At the core, it attempts to address shortcomings with edge stability by avoiding the secondary hardening hump and addressing retained austenite issues. At the end of the project there is little bit more to it than that, but that is it in a nut shell.
There is not a huge difference between Delta 3V and the un-named low temper tweak we were using that immediately preceded it. They're related processes, the primary functional difference being improved edge durability with the Delta version. This difference shows up in side by side testing in rough use but I think most folks would like the immediate predecessor just fine, it was no slouch. Something similar to that predecessor is available to everybody at Peter's and it is a good HT.
A few years ago we (Dan, Guy and I) noticed an issue with the low temperature tweak with some lots of 3V. The problem boiled down to the material condition, but while investigating it we decided to fully investigate the effects of several variables on edge stability, their effect on each other, and to confirm or verify some assumptions we'd had coming into it. The end result was fine tuning several specific variables and we found that the process both worked better and was more consistent when we added a couple steps. There are a few areas where we've changed the way a few steps are done that required some changes at Peter's in order to duplicate them.
I was always open about the tweaks I was doing on D2 and 3V, but when it came time to really do the exhaustive work of fully optimizing the HT on 3V it was a time consuming and expensive collaboration with Dan, Guy and myself. I enjoy discussing these things and sharing what I've learned with this group, but at this point I am unable to discuss details because it is a propriety process shared among the three collaborators.
Folks need to keep in mind the development of tweaked 3V has been on-going for years. We finally did the formalized R&D to put-to-bed the fully optimized tweak and named it, but the previous tweaks were good tweaks. It was named Delta 3V because it was a change (Delta) to the previous process, the end result was different enough to justify noting the revision.
Two things that I would like to be clear about are: I'm not saying that only Delta 3V is a good HT, a person doing their own heat treat could very well have a very good HT. I would be surprised if a small maker has committed the time and resources to fully optimize a proprietary HT process but I'm not saying it's impossible. Even short of that, I'm sure plenty of folks have very good 3V. The house HT at Peter's is very good. But I'm also saying that unless someone is running our protocol, it isn't Delta 3V. It might be very good, I'm not arguing that, but it isn't the same thing. And I expect that most likely a person could measure a meaningful difference in controlled side-by-side testing.
If a person really does their homework and is prepared to demonstrate it to folks they should name their own process. If it is demonstrably different it deserves to be differentiated. But a person had better do their homework. This is one of those areas where, to the uninitiated it might not seem like a big deal, but I promise you that actually optimizing a complex industrial process for a particular outcome is not trivial or easy. Just setting up to make meaningful comparisons (not just some dude cutting stuff and saying "it cuts good") requires a lot of time and hard work.
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on your openness and humble on ht contribution+accomplishments. Also concurred, HT R&D is an expensive process (likely be low ROI as well 
). Functional Range(FR) is area below capability threshold (aka breaking point). Target intended usage is within FR which warrant N stdev/
