Triple quench secrets to be revealed?(or not)

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Originally posted by Graymaker
I spent a long time in auto mechanics along with many other things
and it was very easy to over analyze and miss the basic things and if you did the rest did not help a hole lot.
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I make this mistake, still, once in a while. I've tried to learn that when I notice myself slaving away down in the minutiae, to pull my head back up to the "10,000 foot level" and look at the big picture. Troubleshooting in particular, especially where you have a lot of existing experience finding difficult problems that do require you to think through the minutiae, can cause one to miss obvious and simple things because your focus was too "close" ... not at a high enough level.

Like being able to argue either side of any particular debate (i.e. putting your early preference for a given side TO the side to analyze the other viewpoint), being able to view problems from various angles and from various altitudes it's a mental model that seems to pay off.

Originally posted by Graymaker
For one I may get some O1 at .85 or as much 1.0 or more carbon,
which one is better for a blade you and I both know which one
but we don't know what we are getting when the factors change with a + or - limit like that and that is just carbon,

and we get what we get and we (at least I) can't even be sure of what we have most the time other
than sending the stuff out to be tested all the time.
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Ed has commented repeatedly on the benefits he has seen from buying a big inventory of stock from the same mill run. It eliminates one pretty big variable from the equation.

What I'm wondering is if any of the steel sources will send you guys a materials certification sheet, a batch or mill-run steel analysis sheet. We demand this kind of paperwork all the time in industry. Of course we also double check it with a Positive Material Identification (PMI) device (being professionally skeptical and having huge safety and business risk if we don't), which typically is done by an x-ray fluorescence machine that can pretty much nail the alloy composition EXCEPT for the carbon content, for which there is a spark tester that does leave a mark on the material (a small one) while gauging the emission spectrum of the spark in estimating carbon content. Those PMI devices are pricey though, $20k on up I believe.

I guess you can probably get a cert sheet if you buy enough volume, or buy straight from the factory, but buying a mill run, depending on the material and the mill, is of course a pretty big investment for one alloy (to state the obvious).

Maybe if enough of you started demanding a photocopy of the mill run certification of analysis, the steel dealers would start obtaining such paperwork on your behalf and passing it along.

Until then, it strikes me as important to have as much testing equipment as you can in your shop, so that if you do get some steel that has more carbon or less carbon, you stand a chance of figuring it out pretty quickly based on the results that flow from your perhaps "typical" heat treat protocol for the stuff after your first blade from that batch of alloy.

Surfing EBay for a used but decent condition Rockwell tester (and some calibration blocks) is just one example of a tool that, if I were a maker (and I might be one day, seriously), I'd sure invest in when I could. Maybe some kind of used or inexpensive microscope. And a temperature controlled oven. And ... and...

Being able to quickly adjust your heat treat based on the alloy analysis and certain other in-shop test results seems like it should be a tractable path.
 
Shane,

Thanks for the kind words and the great quote.

I am always amazed at how much I can learn if I simply choose to pay attention. I'm not only speaking about knives and their making but of myself as well. Thanks for the reminder to pay attention.

Thanks to everyone who has contributed to this thread so far! Even if we all don't see exactly eye to eye on all issues, I truly believe that new horizons have and will continually be opened up for those of us who choose to pay attention.

Rick
 
well...the DaQo'tah is still not sure about as much as he was when he first clicked on to this topic.

Some guys are just so darn sure that doing a 3-heat treatment will do nothing to a blade. That the blade has no way to "remember" the first 2 heats treatments, so the 3rd or the 4th or even the 5th will give you the same results as you got from the first. We always will find there is no difference....

This seems to point to a much faster way for me to finish a blade and start on the handle work..

However we then get see the results of the 1-time heat treated steel and the 3 time heat treated steel, test.

When the steel is broken we notice a huge difference in the steel?

if there had been no difference noticed at all, then that would tend to support the idea that adding the other 2 heat treatments was pointless.

But we see a huge difference?...this was not expected by me based on what I had been hearing....

Now while it is true that I have no idea what the difference might mean to a bladesmith, and how we might be able to fine-tune the steel to make correct use of the way the steel does seem to notice the added 2 heat treatments,,,I believe that this seems to support my search for more information about what can be learned when I use more than one heat treatment on my 5160 forged blades.

Like,,,I have just got in my new Norton Fine India stone (2 inch by 10 inch) and Im starting to read all the forum history about this new tool, and many people have commented that a "edge that can shave hair" is not as important for a true working-man's knife ....this idea seems to be all wrong to me right now,,,but I have much to read and understand about that topic as well as this one....
 
DaQo,

I think this was pointed out before but in case it was not: on the 5160 I treated the single quench was soaked at target temperature. The triple quench was not soaked. Therefore, each quench of the triple quench was not a duplicate of the single quench run.

RL
 
The experiment was set up to demonstrate the importance of getting a sufficient soak. I should also like to point out that for those who make a full or part time living at making blades - Efficiency is necessary for a successful business. If you can get the same results in half the time you can't afford to do it the slow way.
 
Mete,

It's obvious from the pictures that there is a difference in the steel from your test, but...
Please explain to me how it is that the piece of steel that I broke from the tip of my most recent knife looks nothing like the triple quenched piece from your test. It is nothing but smooth fine grain. At least as fine as any file that I have ever broken. No fractures. Could it possibly be that there are many other variables such as quenching medium, temperature of quenching medium, degree of hot or cold working prior to quenching, temperature of the steel at time of quench, etc. that can all play an important part in what we end up with? I've said it twice before, and I'll say it again, the triple quench is part of a package deal. And it really seems to be working great for me. I plan on doing a lot of experimenting soon but I want to get my JS rating out of the way first. As soon as I get that out of the way I'll incorporate the soak w/single quench into the rest of my processes to see how it goes. I promise to let everyone know how it works. But based on What Ed and Wayne published, it doesn't look too promising.

Also, I think that any maker that is trying to make a living at this is probably going to find other things to do between quenches to stay productive. We're used to it from waiting for the epoxy to setup or the handle material to arrive or the...:)

Rick
 
Rick, I will take blame for the testing of the 5160. I sent the pieces to Mete for grain analysis. All your questions about that are answered in this thread, as I specified how it was done with times and all asociated temperatures and etc. if there were any etc.. (I presume you are asking about the 5160 testing. This thread has gone so fast and I have not been able to keep up with it completely of late.)

RL
 
RICK, yes there are many variables, which we discussed, and the test had to eliminate variables otherwise it would have become far too complex. I will repeat again - the better you can control time , temperature and forging variables the better and more consistant your blades will be. 5160 was chosen because it is probably the most common of the knife steels for forging. Soak time for O1 would be longer because of the higher carbon content. We really do need someone to sort out this thread and put it in book form !!!
 
If you guys or someone can some up with your findings
the tests and results, who did what
and a conclusions from this thread,,
that will satisfy proof shown to the findings found here.
I'd be glade to post them on the knife making site I made for you guys.
:) it would prove to be very good reading for many to come..
 
Mete: You spoke of profit, yes you are correct. Profit is the driving force behind the science of industry. Mass production, efficiency and profit are part of what made America.

The difference lies in the motivation behind the craftsman, does he chose make a living making knives or chose to live to make the best knife he can? There will be a difference in the knife he produces based upon his motivation.

Profit comes in many forms.

The choice is up to each individual.
 
Rlinger,
I think that you did a great job following mete's directions. No need to appologize for anything.

I appologize if I implied that you had done anything wrong. I was only trying to point out that there is more than one way to skin a cat and some ways are better than others depending on the results that we as individuals are after.

I think that "finding the best way" is what we are all after. The "best way" will be defined differently by each of us depending on our personal goals. But then I guess Ed has already said that...

Rick
 
Originally posted by mete
Efficiency is necessary for a successful business. If you can get the same results in half the time you can't afford to do it the slow way.
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I'll requote mete so his message is crystal clear, and not obfuscated by the dark cloud of shortcuts... and the implication that shortcuts lead to lower quality...
If you can get the same results in half the time, you can't afford to do it the slow way.
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The key adjective being the word "same".

The corollary to this might be "if the more efficient way leads to a lessening of quality, or performance, or fit/finish, then the successful business person must make a decision about what they stand for, and what market niche they are serving."

Let me offer an example, quoting directly from Bob Dozier's site:
www.dozierknives.com
I find that I would much rather make basic hunting knives from the highest quality tool steels at very reasonable prices, for people who will use them, than spend expensive time hand rubbing a finish for collectors. I will probably make a few fancy knives each year, but my heart is with the knives you see online.

I hope that you will find a knife here that will help make you just a little better woodsman and hunter. I want you to have a knife that will hold an edge better than the most expensive knife in your deer camp.
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Dozier has chosen to bring a high quality, high value, un-fancy, utilitarian knife to market, at very fair prices. He chose his niche. I applaud him in his decision. He gets a lot of quality tools out into people's hands annually, within reasonable delivery times (a couple months).
Originally posted by Ed Fowler
The difference lies in the motivation behind the craftsman, does he chose make a living making knives or chose to live to make the best knife he can? There will be a difference in the knife he produces based upon his motivation.
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Luckily, the choice does not necessarily force you into mutually exclusive decisions. Many pursue the making of the best knife they can, and also make a living making knives.

But I believe I understand Ed's point. I can, in fact, but not on this forum, cite a handful of makers who I believe are driven by profit foremost (high revenue), and their drive to make the best knife they know how (at their price point) is a secondary... or perhaps tertiary concern.
 
rlinger....

Oh, ...darn...see I didnt understand that part about soak time...

well,,,,how about your view of a question I ask now then that might help me understand your views about 5160 steel...

Lets say I forge in the morning 2 blades, both from the same John deere load shaft, both the same size..

both are forged the very same way at the very same time....so that they are a copy of each other in every way ,,,

then I heat treat the first once, heating just the cutting edge then quenching in heated oil,,,once cool I temper in an oven....

the 2nd blade gets all of the above, but before I do any tempering, I re-heat treat 2 more times.....them temper as normal...
(NO SOAKING AT ALL)

The blade from one heat treatment will be the same as blade from 3?

That no matter how you test them, break them, cut with them or bend them,,you could never tell the difference between the blades?
 
Originally posted by DaQo'tah Forge
rlinger....

That no matter how you test them, break them, cut with them or bend them,,you could never tell the difference between the blades?
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D'kota,
Other than eating popcorn and watching this thread I haven't contributed beans.

There is more to it than just a "single quench" or a "three quench approach" as you alluded to...if you re-read some of Mr. Cashen's comments, especially concerning the effects of all of the heats. Normalizing and thermal cycling have a profound effect on the outcome. For example if the steel is overheated during the forging process you will see a difference. It is a combination of all aspects of the process. This is referred to as a holistic approach. Doing this affects it this way, doing that affects it this other way.

You will find that most smiths, once they find the method that works for them, they hardly, if ever, stray from it. Testing is one thing but I believe to be consistent, we all keep to a standard methodology once it is found.

I'll give you a correlation. Almost anyone can brew beer, right?

However...

To get it to taste the same EACH AND EVERY TIME is an art form.

Would you continue to buy your favorite brew if it tasted differently each and every time? Of course not!

Its not just down to single quench or triple quench, its much, much more than that.
 
C L Wilkins...

Perhaps I did not write down my question to give you the heart of the questioned matter Im asking about...

I wish to know his views on a blade Heat treated (the way I do it) one time, and that very same blade heat treated three times?


the same blade,,,,same everything,,,not different at all except for the added 2 heat treatments...

Im asking so I understand clearly what everyone has been saying apart from this "soak" matter.....I dont soak my blades,,,but I do Heat treat them as I have talked about....I can do this once,,,or many more times...I wish to understand if the one heat treatment and the 3 heat treatment blade are any different in any way?

So...in your mind, forge 2 blades, each the pure copy of the other,,,then heat treat one of the blades 2 more times than the other,,,mix the blades up,,,now test them in any and all ways known to man to test them,,,Rc test, Electric-gun test. bend them, cut rope, cut fish, cut steel, break them,,,whatever type of test you got in mind...the question is..

"Will you be able to notice any difference based on one haveing had 2 extra heat treatments?"
 
Originally posted by C L Wilkins
I'll give you a correlation. Almost anyone can brew beer, right?

However...

To get it to taste the same EACH AND EVERY TIME is an art form.
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Right... just look at McDonald's... same great food, no matter where in the USA you partake. Same with Miller Lite... great taste, less filling, every time I can stand to drink it. ;)

Just kidding. Sorta.

Consistency doesn't get you quality, though.

High quality food, high quality beer, high performing blades... takes experimentation, knowledge of and acquisition of quality ingredients, and it usually isn't cheap in terms of ingredients or time expended in output.

Consistency is good once you have the quality/performance nailed.
 
Good morning everybody!

Out of all the folks who particpiated in this thread, Rick was the only one who released the results of his multi-quench knife tests.

There was a lot of banter and ideas were exchanged, but Rick destroyed a blade for the cause.

Does anybody on the single quench side of things have some results?

Also I wanted to ask another general question about knifemaking.

It goes back to the idea of steel memory.This question comes from my notes at the ABS school...

During the initial grinding, is it ok to heat the blade up while grinding? I am not talking about warm to the touch...more like turning it purple and dark blue.

Does this have a negative affect on blade steel? Or as would be suggested that thermal cycles will erase any previous thermal strangeness?

Going to work now.

Shane
 
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