O1, again

I've battered you quite a bit, so I'll offer a cryptic hint in parting. This has been mentioned a couple times and you've missed it:

If it's not austenite it can't convert to martensite when you quench.

Figure that one out and you'll add another piece to a puzzle. I am honored to see our efforts have made you learn something. :p
 
I'm no dummy, so that either means one or both of the following:
1) The proper temperature to bring as much steel into the austenite form must be achieved and/or (probably and)
2) The proper duration of the heat must be maintained to allow the austenite formation to occur over a given period of time. Hence, the soak. Lightbulb on!

Now here's one more question... is it possible to do a soak in a forge without temeprature controls, or are we into the realm of the molten salts/heat treat oven apparatus? My forge doesn't get super hot, and I've soaked O1 for a minute or two and it didn't seem like it was going to melt or that it was getting funky in any way, but obviously a lot of this stuff happens on a microscopic level. Would setting it in my forge and going outside for a leisurely gin and tonic, then coming back, do more harm than good, assuming my forge temp seems to top off somewhere not too far beyond the non-mag temp of O1? I may be asking Sean for his crazy salt bath tutorial, on second thought.
 
One can always buy a pyrometer and thermocouple and regulate the temp that way if they have sufficient control of the forge.

Since you're no dummy, go back and read Kim's post. Just because the lightbulb's on doesn't mean the dimmer's turned up all the way..... :p He gave you a real big hint. Write him, he may explain the rest.

You have to understand, I am not going to give you direct answers. That's too easy, and you'll only learn what you need for the task at hand. I will help try and steer you to draw the proper conclusions, but not spoon feed. That is to your distinct advantage in the long run, as I'm sure you're aware.

I sorta liked Mark's $5/question thing.... :eek:
 
mete, I would appreciate it if you could send me the paper too: email removed

I could also put it up on a web server so everybody can get access to it from there, if it is legal (don't know if there would be copyright restrictions).

Thanks.
 
Another hint; The curves drawn on the TTT diagram are not the cooling curves that the steel will follow, so technically by cooling the steel in such a way, I have upto 15 minutes before I start transforming the Austenite into anything but Martensite.
 
Chiro, SOAK is to dissolve the carbides and diffuse the carbon uniformly......I'm now having problems sending the Ohio State paper . I'll see if I can find the new url, be patient.
 
I found this one a few hours ago. Not sure it is the same one you are looking for:

HT Info

Then I got hung up in Crucibles website looking and reading. Crazy cool stuff going on there.
 
I have a couple of books that might help you. I don't want to sell mine and I am not sure if you can find them at your library, but you can buy them online. The first one is by Bill Bryson it is called Heat Treatment, Selection and aplication of tool steels. I found my copy on Ebay. The second one, I bought from Gene Chapman when he was cleaning shop and getting rid of a few things. It is called Hardening, Tempering and Heat Treatment by Tubal Cain.
 
I sorta liked Mark's $5/question thing....
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Cool with me, but keep in mind when people pay for the right to ask questions, they expect a lot more from the answers.

Mete's paper is solid gold. I found a lot of interesting stuff so far, like what banding actually is, HOW grain growth occurs (not that is just DOES grow), etc.

One question from the paper, and now this is getting even more off topic: is critical temperature/non-magnetic (I know they're not exactly the same thing, but bear with me), when full austenite formation has occurred in the FCC solid solution?

For those who haven't read this paper yet, the bottom line is if you're using O1 and not using something with temperature control, you're doing it wrong, according to the book. Sorry, beginners (and advanced people who've been doing it wrong their whole careers)! At least I'm finding out about it on the ground floor! :p

Here's what I want to know: how much different does properly soaked O1 behave from O1 that is heat treated the way it sounds like most knifemakers do it (not soaking it)? In other words, we've established pretty handily that soaking O1 for some period of time at some temperature makes sense. Now, in the real world, and out of the dusty textbooks, does it actually make a diifference when the knife is used, and if so, how? Is it tougher? Does it hold a better edge? Etc? In other words, we know that the textbook says "Do XYZ" and some makers do that, while an awful lot of makers to "ABC" and make very fine knives that don't break, lose their edge quickly, or otherwise get many complaints. So, the bottom line is, beyond the academic and textbook, in the real world is the extra effort meaningful enough to warrant that everyone run out and buy salt pots or heat treat ovens if they don't already have them?
 
When I first started making knives, they were for gifts to relatives and friends. The more I learned the better they got, heat treat as well as looks. The knives I make today will not be as good as the ones I make next year but they are as good as I can get them. When I first started selling my knives, they didn't sell for what I can get for them now because they weren't as good. Some makers will only make them "that's good enought" and will never get better. The market will soon be saturated with the knives they can sell and then they will drop out or almost quit. In my area, there is a lot of Native American made knives and it seems the tourists prefer the crude look that a lot of them make. As long as they buy them, they will make them. Do you want to make tourist knives or do you want to continue to do better. Please do not compare all knife makers as being the same.
The difference in performance between the average knife and the best you can do will increase as time, experience, and knowledge increase. No more knowledge, no more improvement in performance. Most of all the posters on this thread know that you can sell an average knife but it should always be the best you can make it. That is the "Real World".
Just my thoughts this morning. I had no idea that there was this much to learn when I started and no idea how much more there is to learn.
Have a good day.
 
Chiro75 said:
the bottom line is if you're using O1 and not using something with temperature control, you're doing it wrong, according to the book. Sorry, beginners (and advanced people who've been doing it wrong their whole careers)!
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what does this tell you about learning to use a torch and a toaster?
Read this Chiro...
http://www.bgoodeknives.com/wireedgereview.htm

Thats why its an art. If your the type of pearson who can listen yo his gut (some know what I mean) and learn from it, knifemaking will be either very by the book or not too successful for you. LEarn to read the heat....
are you heat treating in a dark room away from a window? BE honest.............

Edited to add : You need to do alot of testing and experimentation for what will work in your shop. Untill you do that you cant truley learn what is going on. Thats just my .02 cents.
 
Raker: I agree. I guess what I'm asking is this: if Knife A is made one way, and Knife B is made another way, and they look identical and perform in the real world indentically, but one process is easier to do than another, does it make sense to take the hard way? In other words, does the textbook way lead to better performance and a better knife, or is it more at an academic level? A good project would be to grind two identical knives (as close as possible) HT them two different ways and text them out, obviously, but from the people who've used O1 the textbook way and what seems like the common way it is generally used, what are the performance benefits noted? Would you notice the performance benefits in a blind "taste test?" This could make for an interesting knifemakers only passaround, actually!

Brian: I heat treat in a dark garage, with magnets in hand, doors closed, usually late in the evening. But, according to what we've learned here, you're probably one of the guys doing it wrong. I'm not trying to offend you, but I'm saying you're probably not doing it the way the "book" would say, that is, precisely soaking the steel to maximize carbide dissolution, austenite formation without overdoing it and producing larger grain. I know another knifemaker who, if O1 becomes extinct is probably the reason why, and he does it pretty much the same way you do, too. His knives are used very hard and I've never seen a single bad review or negative comment. This is EXACTLY what I'm talking about. Does the extra effort of treating O1 the way it sounds like it needs to be treated, by the book, very carefully as it were, translate into real world benefits that can be noticed beyond the microscope?

And, just so you know, my shop is full of knives that I've kept from every steel I've used and a variety of different grinds and I use the heck out of them, so I have a decent idea of what my knives will/won't do.
 
All I have to go on is use and testing. Cant speak for whats in the literature so if I am wrong so be it. :p I can say that ?IF? you have a hold on 1095 like you say, 0-1 should be a piece of cake for you. I think your judging temper line on steel hardness. Not the same animal and 0-1 is teaching you something my friend. Learn 0-1 and you will have a better grasp on 1095 and so on.
 
IF? you have a hold on 1095 like you say, 0-1 should be a piece of cake for you
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Which it will be next time I use it. The whole "problem" I was having was not seeing any discernible temper line because I was through-hardening the steel. I didn't have the knowledge that O1 quenches totally differently from 1095. So far my tests with my second O1 knife show that it is a great knife, it just doesn't have a temper line where I expected it, so I naturally assumed that it didn't harden. It passes a brass rod test with flying colors and I've been chopping the hell out of stuff with it with no problems, either. Now that I know I have to quench it differently if I want differential hardness, it's no problem. Next step is getting a salt pot going, which I need to do a more consistent normalization process on for 1095, anyway.

Your whole "gut vs brain" argument is exactly what I'm getting "beaten up" on in this thread. You prove my argument that the textbook and what some knifemakers, maybe a lot of knifemakers, differ and yet you're making good knives AND you're saying you don't really care what the textbook says because your knives have the level of performance you're looking for. I get beaten up for saying "I followed my gut, and this seems like a pretty durn good knife" because it flies in the face of the scientific knowledge concerning the properties in the metal we're after. So, which is it, guys? Knives that perform well, knives that follow a scientific procedure, or (well the right answer is obvious) knives that follow a scientific procedure AND perform well? Sean, I'll be getting in touch with you concerning salt pots.
 
To some, microscopic variations are enough to motivate them to continually push the envelope (besides how many folks decide to go with a business who says "eh.. we do things good enough"). But the real benefit from following the manufacturers suggestions is consistency. I simply could not function if I could not rely upon consistant and predictable results in my process.

Your point of doing things the simple way makes complete sense, simplicity is the heart of consistency, simplicity eliminates variables. But that puts your point directly in the column supporting following the book and the spec. sheets. "Heat to 1480F., soak for 8 minutes quench imediately into 160F. Park AAA. Temper immediately", now compare that to some of the more "interesting" rituals I have personally witnessed that bladesmiths can come up with, and the simpler and more consistent method will be obvious.
 
I learned in art school to take what the book tells you and use that to make it work for you. You dont have to cook only following the exact recipe to get an awesome cake.

I dont have an oven right now so I have to rely on the soak time I can achieve with the torch and learn to adjust my temperature to hold the steel at what I feel is a good temperature to do the work. I can tell right away when I didnt do it right. I have rc sample blocks to check with a file against my knife blades. If the file bites differently I can feel it easily. Maybe you should heat treat some 0-1, 1095, and 1080 and send those off and get an RC number on them.

Do guys like Moran use an oven or salt pots? Maybe someone can let us in on this info.

I am getting like Fitzo now - You need to take the info and practice it. Spending more time to battle over whats right can get old fast.

Hope I helped Steve.
 
It's not extremely difficult to make a forge run with digital temperature control.

That's what a salt bath is...

You will not have the same benefits of exact temp control and an oxygen free atmostphere... BUT, you will have temp control that will be within good tolerances, AND allow you to soak without blowing up a blade.

You need a digital controller, a K thermocouple, lead wire, a gas solenoid, and a relay.

You can buy this all for about $275-300.

That is extremely cheap for the benefits.

:)
-Nick-
 
Chiro75 said:
Cool with me, but keep in mind when people pay for the right to ask questions, they expect a lot more from the answers.
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But, grasshopper, it's that thing about the bread, again. If we can succeed in making you seek and think at a more fundamental level and thus have an epiphany, is that not priceless? :)

$5 was the pittance necessary to make the seeker realize the teaching has value.
 
Ray Kirk, I have reread your post at least a half-dozen times. I find that very eloquent and such wonderful wisdom I wish we could use it as a masthead for this forum.

Thank you, sir! :)
 
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