The Logic of Heat Treating Oils

[Dan Gray]

Times differ from person to person, of course. I was more worried about the temp. I time it 20 minutes after 1950 because it spends about 10 minutes to get there from 1900 in my furnace.

I was trying to save any embarassment of someone noticing, "Well, at 1850, maybe you finally got some hard spots after 2 hours!" (That's a joke, that's a joke, that's a joke. )

hahaha :thumbup:




Me thinks me smells pop corn burning though
I'm going to hide somewhere..

 

[fitzo]

Me thinks me smells pop corn burning though
I'm going to hide somewhere..

Nah, I think the "subjective" had to do with the talk about what's art and what's science we engaged in. After that gets straightened out we'll be able to learn from two people this is all very important to. A good thing for us.

 

[Kevin R. Cashen]

Kevin
not to cause friction or anything but you got me wondering now..
just a question because it seams related to what you just said can't happen so I need to know .
please tell me what happen to a blade I once left in the oven once for 2 hours, I totally forgot it,,it shoud have been out in 15min's...

No problem Dan, answering a question feels better than asking them right now. If you problem was grain growth, it would have to do with the temperatures at which the more tenacious alloy carbides will eventually let go. At 1950F you are up there, that is why you go to those temperatures with such rich alloys in order to get all that stuff into solution. The carbides still let go at the same temperatures, you just have a whole lot more of them.

But most simple steels, lets face it O-1 and 52100 are quite simple compared to 154CM, can be successfully heat treated at much lower temperatures. As I mentioned before, diffusion is both temperature and time dependant but temperature is incredibly more powerful than time, not to mention that times for diffusion become much shorter the higher in temperature you go. But if you have chromium carbides sitting in the grain boundary and only heat to 1500F that grain boundary isn’t going anywhere until those carbides let it. At 1950F that grain boundary is going to do whatever it wants in short order. In steels like W-2 or O-1 you will often find around .25% vanadium added specifically as a grain refiner because these steels will seldom see temperatures neccesarry to dissolve a v-carbide they will sit there and keep the grains in check.

Your white specks are hard to comment on without seeing them, but the fact that your blade seemed harder is no surprise. When you pull more things into solution not only do you get more carbon trapped in the matrix, but you also leave less points for anything else to get t toehold in forming except martensite. This is more applicable to oil hardening steels than air hardeners, of course.

For more information on the topic, Bain touches on it in “Principles of Heat Treatment”, and deals with it more in depth in “Alloying Elements in Steel”. Verhoeven covers it in “Fundamentals of Physical Metallurgy” and explains it quite well in his much referenced “Metallurgy of Steel for Bladesmiths & Others who Heat Treat and Forge Steel” (which also has an in interesting chapter that covers ultrafine grain sizes,coincidentally). I could go on since it is covered in most metallurgical texts, but that should handle the “science” side of it. I understand that much emphasis is also put on personal testing, so I will also point to my own testing and observation, which to no surprise to me, falls entirely in line with what these gentlemen have written, but I had to see for myself all the same

 

[Kevin R. Cashen]

Ed:

Please accept my assurances that I was not referring to your theories on grain growth processes when I mentioned things that came up much earlier in the thread. You will notice the last post I made before my addressing the current issue I mentioned that this thread had the potential to spin off into a thousand possible tangents. Fitzo is correct that I found the attempts to establish what is “art”’ and what is “science” and what each person may feel as desired performance in a blade, as totally subjective, as it indeed is and could produce nothing but a deviation from the original topic to attempt to debate it.

Eutectoid? Come on now Ed I think you grasp a lot more than what you are letting on now. Modesty may have you with the 5th graders, if so you are the sharpest 5th grader I ever saw. Heck you referred to “fine grain in a matrix” and totally lost me and I am no stranger to the terms. I wasn’t asking you to use much of what I myself will admit is often so much techno-babble, as often the point can get lost with it. I can understand that, since I am more of a nerd than the poetic type so I have a hard time seeing the important points within some poetic metaphors and philosophical musings. I see hypereutectoid, you see “Lady Blade”, perhaps we could use an interpreter.

I am glad to hear that you have developed good empirical evaluation since that would be just the thing to help me understand what I may have not found yet about soak times and grain growth, which I totally agree with you that there shouldn’t be anything subjective about it, but perhaps there is something I am overlooking, so please elaborate.

You are no small figure to disagree with, doing so gives me no pleasure at all and I hope you take that as sincerely as it is given. Rest easy that you have not upset me Ed, I am upsetting myself with my compulsive need to get to the bottom of things that I do not understand, even at the expense of tact and decorum, which I do regret.

 

[Dan Gray]

Thanks Kevin

You are no small figure to disagree with, doing so gives me no pleasure at all and I hope you take that as sincerely as it is given. Rest easy that you have not upset me Ed, I am upsetting myself with my compulsive need to get to the bottom of things that I do not understand, even at the expense of tact and decorum, which I do regret.

hey you guys are Cool in my book

it's amazing to speak the same language and still have problems understanding each other most of the time.

I got to thinking last night rolleyes: ) you know I don't mind blabbing off to find out things....
thinking about all this..
Kevin you read history, things that have been discovered written into great books and then prove them to your self, but thinking about it it is still history from the point to where it was written and that book from that point on and concerns only what it has to offer about history, not the future,
from that point on, history is still being made (I'm sure you know this and it doesn't have to be said) and some of it I'm sure good BUT not put into the books until someone with enough stature places it in the texts books, for guys as your self, Robert and all the rest.
This is just me, because I tend to give a benefit of dought unless I can prove other wise something not right, but until someone tests Ed's blades to either announce or denounce what he has done and claims, I have nothing to say about it. nor for that matter to say anything about all the facts you believe in, I mess up terms all the time, it's just not in me to remember that stuff but as long as I can do the job right or close to it as I can, I'm not sure if the job is only half done if I mess up the terms, I think I can show hands on but just not explain myself well or why it happens.
some if not most of us can only sit back and say ok who's right here or are they both right in their own direction? for some of us if we were told carbides was a marshmelowbite who are we to argue?

what I'm saying, for us like myself, I have to say, is ED into something that just has not been put into your type of text books yet? am I right or am I wrong ? I don't know..I can't argue with what I don't know..

we all want truth and One thing that comes to mind is, that was a hot topic was edge packing..
be it hype , fiction or truth as you know, some believe it just because they want to believe in it..be it from a mentor or argued to be so by many without proper testing to prove it.
Ed seems to have had a bunch of this (lab testing) done concerning where he's heading with his blades.. OK I'm rambling again..but do you see some of my points?
though my inability to write fluently.

 

[Kevin R. Cashen]

Thanks Kevin...
... what I'm saying, for us like myself, I have to say, is ED into something that just has not been put into your type of text books yet? am I right or am I wrong ? I don't know..I can't argue with what I don't know..

A safe thing to always say is "anything is possible".

Dan your suggestion is not new to this topic, which is why I would like to bring up something about guys like Bain, Grossman and Verhoeven, or Einstein, Bhor and Heisenburg and why they hold such credibility, it is not just because they wrote those books. One major factor is the concept of peer review. If any of those guys produced a theory that challenged the established wisdom they knew that it would be scrutinized and picked thoroughly apart by their peers and thus they needed to have irrefutable evidence and facts before attempting the challenge, and the burden was solely upon them to prove why established wisdom was wrong. If the position survived peer review, it was sound enough with all concerned in the field to stand on its own.

I mentioned Einstein Borh and Heisenburg on purpose, since they had theories that stood up quite well, yet were somewhat at odds with each other if you used them interchangeably. After the success of General Relativity, Einstein spent the rest of his life working on a grand unifying theory that would reconcile the differences. He even thought he had it a couple of times, only to have it promptly slapped down when his peers found flaws in his work. Most would want that theory to work because it would make us all feel better about our universe and whether god does “play dice”. And who wants to believe that Einstein could be wrong, but not even Einstein was immune to peer review, it is what established his best theories and what weeded out his less than perfect ones.

I will never forget a conversation I had one year at the Badger show with my friend Mike Blue, we were discussing why there are so many widespread misconceptions in this business and Mike pointed out that there is no peer review among knifemakers. Indeed it is somehow considered rude or hostile to even attempt it, which may be why I slept so lousy last night. If we could get rid of this wall I think everybody would benefit from a practice that benefits the researchers in most other fields.

 

[Dan Gray]

there is no peer review among knifemakers. Indeed it is somehow considered rude or hostile to even attempt it,

If we could get rid of this wall I think everybody would benefit from a practice that benefits the researchers in most other fields.

kind of like the ABS but with labs and metal geeks and allowing all makers
and steels in and get your blades stamped or not
how about the
ABTRA, The American blade testing and research association,
our motto is
You make them we'll brake them

Thanks Kevin

 

[Ed Fowler]

Kevin: Thank you for explaining the subjective deal, I readilly accept challenge, or peer review for the debate many times gives me more ideas, variables to play with.
Subjective: I chose to make my kind of knife for many reasons. I wish to explore the frontier of independant man who needs a tool that he can depend on. In my mind he does not need any of the fancy steels, a simple steel like 52100 has more potential and fewer congenital faults. Kind of like the beauty contest winner, she may or may not be fertile, may or may not be a good mother or partner in life for her mate, but she will make the cover of Time Magazine and fill the dreams of many.

The simple steel intrigues me, easily understood after 20 years of working with it every day. One aspect that has worked well for me was my choice to work with one steel and learn her well. I believe that we are making a team, she is always there for me unless I really take a wrong turn. This may be one venue that confuses our debate, I am thinking 52100, you are thinking variables that 52100 does not have.

The peer review is a viable concept, when peers are without predjudice. Einstein had no peers. Columbus would have never sailed, etc. We can learn from those who go where no one has ever gone, as well as from those who
can pick out the true lessons of history. Many of the most valuable lessons are hidden in the 'facts' as they were recorded and only mentioned in passing.

(When I started writing about low temperature high percentage reduction by forging, and leaving the edge thick through the hardening process I came very close to being evicted from the ABS for heressy. Peer review almost became censorship the difference is a very fine line rarely understood by those in power.

Edge packing is one of those catch phrases and elicits a lot of emotion. Historically it was an esoteric acomplishment achieved by a chosen few, then discredited by many. Today I believe it exists but can be achieved in a manner far from the simplistic methods that were used to describe its development. Many used the theory to promote what they did not understand and could not achieve. Today the term is laughed at.

Take away the term edge packing and call it something else and some will be able to understand without the predjudice the term evokes. Call it thermal packing, grain refinement whatever, the concept is one of great value if we can achieve it. It will not come from a single event, but through the careful development of the blade through events from the choice of steel, method of development, including quenching oil (to stick to the topic of the thread) and I believe the achievement can best be described through the evaluation of what it is for, performance. Once performace is achieved, science can describe it. With the right man of science available and willing to stick his neck out science can be a great aid.

I continue to try to explain, I keep no secrets. Some issues I shy from simply because I know they will cause great turbulence if opened for discussion. When students come to a Willow Bow Ranch seminar they leave with an understanding that can only be understood through hands on experience. It is not the complicated issues or events but the simple process where the breakdown in communication occurs.

I agree with you, the two of us need an interperter to understand the other's thoughts, and maybe even our own.

 

[cmd]

Ok, nuff of this !

McMaster sells quenching oil by gallon (as low as $10):

goto www.mcmaster.com, look @ page # 2029
(simply enter 2029 into the search box on upper left).

Much appreciated rashid11. I have sent a couple of emails with no response and have been talking with sales people from heatbath (Park) for about a week now and have gotten absolutely nowhere with them, even agreeing to the $100 minimum order.

To be clear about my earlier comment, it was my guess as to why some people do not use "real" quenchant but not that it was a wise decision.

I hate having to beg and plead and still get ignored when trying to buy something. mcmaster will be getting an order from me very soon!

Chris

 

[Kevin R. Cashen]

I think my last post has been entirely misunderstood. Believe me, I am not suggesting that any sort of governing organization for peer review, that would be an unmitigated disaster, the ABS has enough problems trying to set even minimal standards. I am just asking why the very idea of our peers asking for data to support our extraordinary claims is so radical to us.

Scrutiny of claims needs to be evenhanded as well. When it was suggested that a torch may not offer the same control as an oven, folks felt darned obligated to explain themselves or apologize to those using torches. Every metallurgical text I have read, every professional heat treater, and every spec sheet I have ever read all give recommended soak times, yet when it is suggested that ovens or soaking have negative effects, it just goes unchallenged until I decided to be the jerk. Let’s all think about that.

Einstein certainly did have peers, I believe that was covered in my last post, folks like Max Planck helped lend credibility to his earlier work while Einstein was but a humble patent clerk and it was their scrutiny that elevated him to us believing he had no peers. Bohr held his own quite well debating him (it was Borh who told him not to tell God what to do with his dice concerning quantum theory). But that is neither here nor there, except that peer review doesn’t keep anybody from doing their own thing it just necessitates the responsibility to provide some facts to back extraordinary claims.

I always feel uncomfortable comparing knifemakers to famous explorers. We do just make knives, and it really only applies if you are going somewhere that nobody has ever gone before. More often than not we are backyard explorers hacking a trail through the brush aside a four lane expressway that has been there for 50 years. It is all a matter of perspective. Columbus took a chance by venturing into the unknown but let us not forget that his original mission was ultimately a failure because they could not let go of the fantasy of finding quick route to the Orient. All the same he certainly knew he had to have more than just stories when he returned to Spain.

I think cmd, has the right idea in talking quench oils again in a thread called "The Logic of Heat treating oils".


Ed, for peace of mind I am ready to put this one to bed so long as you give me permission to ask questions anytime in the future when I don’t quite get where you are coming from, as you know I do like to ask questions .

 

[ghost squire]

More often than not we are backyard explorers hacking a trail through the brush aside a four lane expressway that has been there for 50 years. It is all a matter of perspective.

I love that! It perfectly describes my journey in the world of knives.

 

[Dan Gray]

we are backyard explorers hacking a trail through the brush aside a four lane expressway that has been there for 50 years.

and you said you weren't poetic, you're holding back on us Kevin..

 

[Ed Fowler]

Hello Kevin: I love it when you ask questions, like I said, it feeds my brain and keeps me sharp. I wish you luck in your knife stuff.

About ovens and torches: When ever we sacrifice freedom for control we loose what that freedom could have nurtured. That is what using the torch means to me, freedom from soak times, freedom to put the heat where I want it and at the rate I want.

I and others on this form know of makers who have gone to the mill instead of doing their grinding free hand. I asked one why he had dropped as aspect of blade geometry that I liked, he said he had to because his mill could not perform that function. While the mill was a good thing in some arenas, it cost his freedom do continue to do what he also liked.

The more we rely on hardware the more it costs. Sometimes the hardware opens the gate to more, but we have got to watch our dependancy carefully or one day that machine comes to control us.

 

[Chant]

To all you experienced guys, esp. Kevin, Ed and Dan:

I'd just like to express my thanks to you for carrying on these debates in a public forum.

While it may cause you some distress or concern to be driven to explain your positions, and to try to speak the same language, and to open yourselves up to critisicm on a subject that people feel very strongly about, it opens up a world of "thinking" for me, and, I'm positive, for many others who have been following.

I have gleaned a lot from following the arguments on this thread -- and it will be of great use while I'm hacking my own trail aside the expressway.

Your courage, civility, and willingness to share, to disagree, and to agree is golden :thumbup:

 

[fitzo]

........... Every metallurgical text I have read, every professional heat treater, and every spec sheet I have ever read all give recommended soak times, yet when it is suggested that ovens or soaking have negative effects, it just goes unchallenged until I decided to be the jerk. Let’s all think about that.

Sorry to have let you down, Kevin. Surely you understand the phrase "tilting at windmills." I have privately expressed to you my sense of futility at discussing metallurgy and HT in forums before, especially in certain situations.

I had hoped that there would be dialogue amongst people with a deeper understanding than I that would explain why the possibly slower heating rate occuring in a furnace as opposed to a torch may impact grain growth once the grain gets fine enough. It makes little sense to me, but then perhaps I needed to learn something new. Thus the hesitation to question it personally and leaving it for you, far more qualified on several levels to pursue the point.

Sorry if that has made you feel like a sacrificial goat. It wasn't intended.

 

[John Frankl]

Ed wrote:

"I continue to try to explain, I keep no secrets. Some issues I shy from simply because I know they will cause great turbulence if opened for discussion. When students come to a Willow Bow Ranch seminar they leave with an understanding that can only be understood through hands on experience. It is not the complicated issues or events but the simple process where the breakdown in communication occurs."

This, to my mind, is where Ed really shines. As I posted earlier, I have learned so much from his unselfish sharing of his own methods and experiments. People will always settle on their own methods, but no one will ever doubt Ed's generosity and passion for this art/craft/science.

John

 

[ghost squire]

Ungh... I just went back and read the entire thread.

So there are differing views on the subject of grain growth and soak times?

Am I to understand that Mr. Cashen believes that longer soak times (corresponding to an oven?) do not generally cause enlarged grain size, and Mr. Fowler believes that they do?

Couldn't you just preheat the Paragon or whatever then stick the knife in?

Size 14 grains... If you let me in on your secret I promise not to tell anyone and not to sell knives! Half joking here LOL

 

[Kelvin R. Cashew]

Before proceeding, I suggest that everyone read my article entitled The Anatomy of Tripe. (Tripe is the muscular lining of a cow's stomach.) The article can be found on my Matterhorn Forge website; Matterhorn Forge

Recently, I was discussing the issue of tripe with my good friend "Meat". Despite all of his years as a metallllurgist, Meat could not understand why anyone would want to swallow all that tripe in the first place. “For God’s sake Kelvin, that crap will rot your brain” he says. I tried pointing out that some people will gobble up any silly notion they are presented with. They want to believe that Grandpa’s secret recipe can magically transform that tripe into something worthwhile. But it takes a good deal of effort to actually read the professional cookbook and learn how to make a proper meal. I guess it’s all just a matter of personal preference, do you want to make a healthy dinner, or are you willing to settle for tripe.

 

[Stacy E. Apelt - Bladesmith]

I'm not sure Guys,but I think the original question was..."Do you turn the knob right or left to raise the temperature on the HT oven."

 

[Chant]

Great article, Kevin. And great writing -- you really ought to finish that book. Hell, I'll buy two copies.

If you ever need a break from metallurgy, you'd probably enjoy studying a relatively new field of scientific study, usually refered to as "social dominance theory".

It basically involves the study of individual human behavior by examining that behavior within the context of the larger social dominance hierarchies that humans (and other primates) form.

Fascinating stuff. One of the things it attempts to explain is why people "...swallow all that tripe in the first place". It is not just naivity or stupidity -- rather it is a genetically encoded behavior that natural selection has "selected" in order to maintain the cohesion of the social dominance hierarchy. One would like to think that humans would be able to apply their minds and think themselves out of this evolved behavior, but so far, as a group, we seem to be sticking to the program.

Re: your "banging on the dead horse" glyph -- keep banging, some of us are listening.