??poor mans quench??

[stingray4540]

Mr Purple: Well that's kinda the point. I really don't have an opinion as of yet, because I have not done any heat treating. I just don't think that it's fair to say that this thread doesn't apply to me, when the stipulations of the question were that the oil be cheap, easy to get, and doesn't have to be ordered, and I passed on information that I've come across in my research that met those requirements. Sure he will probably produce better stuff by following your advice, and I'm not saying that he shouldn't, but your advice doesn't quite meet the original requirements. Not to say that he hasn't changed his mind since then.

Like I've said before, I'm a newb myself and am still learning and am open to any and all advice I can get to make my work as good as possible, but I do not have an unlimited budget either, as I am a student and am married, so I not only have to be able to afford it, I also have to get my wife's approval which isn't an easy task, especially when it comes to my new hobby.

P.S. Thanks for the example, but I'm not using 1095, neither do I plan to so it doesn't help me much. Got any examples that deal with 1080? In fact if anyone can supply it, I would love to see a direct comparison between cooking or motor oil and quenching oil. Any kind of comparrison would be cool, whether it be a magnification comparrison or a scratch comparison, or whatever, it would be interesting and informative.

 

[Whoever Wherever]

Dont get to discouraged with us newbs guys. Your info and willingness to help benefits more people that you know because everytime I surf this site there are tons more people reading than posting. Alot of us would be lost in the woods without solid advice on where to go. Even if not we would certainly take alot longer getting there.

There was a very first knife post not long ago and one acopmplished maker commented on how good peoples knives were looking for there first attempts. I couldnt agree more and give all the credit to willing knife makers everywhere for sharing there trade secrets. To many trades have gone away from lack of this type of cooperation. I owe this forum and a Mr. Frank Ownsby alot for any skills I do now posses in this field.

Stingray all I can say is that we have to strive for our best. Custom makers are easily outshadowed by production and an even greater new threat of amazingly good midtechs even into the 2k price range (for market share at least). If we come here for any advice less than the best advice what are we doing to ourselves? I do understand that many knife makers are trying to get by on a sting and a prayer for budgeting but for to long people wandered without dirrection. I tihnk more than anything these guys want us to know that by using motor oil or such we aernt learning the most esential of info in our work and there was a time when blacksmiths had to spend years on learning now what is basics. By reducing variables we can grow in skill so much faster. My first knife was ground out on a wilton treated in a paragon and homade cyro'd after quench. While I recognize not everyone can be so lucky I use that knife hard and know that if I hadnt listened to advice it wouldn't have been nearly as good. As a result my second knife was even better so on and so forth. Without wondering if I was getting good hardening I was able to focus on grinding and finishing wich need plenty of attention believe me (I've got a ways to go before I come close to the guys advising me).

They are simply saying that much better than all the improvised quenches are known ones with predictable and faster results. People could quench in anything and everything oil like will get suggested but the learning curve is slow when working with lots of unkowns. I dont know any teacher or mentor that wants you to have a hard time and be forced to progress through your problems instead of thinking a way around them. When I stated making knives R.J. Martin told me in an email "Start off small and simple. Understand the process and when you encounter a problem understand why it's happening. Then you can avoid it next time." This advice has served me well and will continue to do so I'm shure.

 

[oupa]

Ed, I would like to applaud your insight and attitude.
I salute you sir, you have gained my respect.
Dirk

 

[fitzo]

Mr. Stingray, I feel that some of your initial posts came off as a bit beligerent, and thus the responses to you. Please forgive me if I have misinterpreted. Perhaps it is simply that frequent frailty of the internet that nuance is difficult to grasp through the printed word; misunderstandings often result.

There is nothing explicitly wrong with you using motor oil as long as you know without doubt that there are professional quench oils that have been specifically engineered to optimize characteristics for hardening steel and will certainly provide better performance. The simple fact is that industry would not use them if they could get by with tankers of used stuff from Jiffy Lube. The problem would come if you decided after modest success that motor oil was "good enough" and sold your knives as being everything they could be.

That said, the concern is to prevent the formation of bad habits by early education. It is well known that if a new task is learned by doing it correctly from the beginning, bad habits do not have to be unlearned later, something that is often difficult to do.

There is a great deal of ignorance, myth, and misplaced hype in custom knifemaking. Please consider most of the responses in this thread as an attempt to educate against that possibility of claiming another victim.

You will find that attempts to dispel those myths are frequent topics on this forum. They result in some polarities which can often seem confrontational. Welcome to the debate.

 

[bodfish]

I think that Mr. Fowler hit it on the head.........let the new guys (including me) experiment a bit.

Sure, I know there are "proper" quenching oils, as well as "proper" grinders, files, heat treatment ovens, "proper" blacksmith coal, and all the rest.

What I "think" the OP wanted was something that he could use right now, to allow him to finish a piece. I think he got some good answers to that one, and some "proper" advice to boot.

What I wished for was a "proper" REASON to buy the good stuff and what might happpen if you didn't do it.

For example:

Would it not harden fast enough? To hard, too fast? With which oil and why?
Seeing as how you temper it back anyway, why do you need to get it as hard as possible first?

And if that's the case, then why not learn to harden in brine? It makes it the hardest, right? I know makers that use nothing but water and have good success...........

Which road should we take on this little walk?

 

[Whoever Wherever]

Bodfish, your point is well taken. However I think the info you are asking for is part of the problem with those quenches. If somone says vegtable oil quenches this fast they could eaily be wrong. It's not all the same. Same with motor oil. Maker, viscosity, lubricants and how dirty with what impurities all compl8icate matters. With Parks 50 per say we can say for shure this is what you are using and this is what should be the results. Without that it is just a shot in the dark. One could say this steel does better with penut oil than mineral, but is it true or just the result of limited experiments with no control? I dont think anyone is saying dont go make your first knife until you have these things. They are just saying this is the best info we have and it suggests you will get unkown results with random oils. The exact proper reason isnt always given becuase with random oil there is no proper data and I dont think anyone wants the headache of trying to catalog and sift through the resluts of every type of motor oil ect.

 

[bodfish]

Bodfish, your point is well taken. random oils. The exact proper reason isnt always given becuase with random oil there is no proper data and I dont think anyone wants the headache of trying to catalog and sift through the resluts of every type of motor oil ect.

Gottcha.........but none of my above questions dealt with any of the makeshift stuff. The questions ALL applied to the real stuff, right?

 

[Whoever Wherever]

Gottcha.........but none of my above questions dealt with any of the makeshift stuff. The questions ALL applied to the real stuff, right?

Lol, sorry I misunderstood. They certainly apply to real stuff quenchants! I think any comercial quenchant will have its speed in its data. Then you just have to match the speed the steel needs with the right quenchant. I dont know if anyone has a chart or list of all common knife steels and the best comercial quench for them (would probably be debatable in some cases anyways). But for any given steel I think it would be easy to get recomendations on what quench oil would be fast enough. I wil deffer to people who have had more time to experiment with more of the comercialy available quench solutions. The biggest risk I do know however, to slow colling and pearlite as a result.

 

[Martin S.]

Bodfish To answer your questions from what I've read, too fast a quench puts a lot of stress in the steel. You might end up cracking a third or more of the blades using water or brine. For a guy making knives for a living that is an unacceptable loss number but for us guys just out to make a knife or two it might be worth the risk IMO.

Too slow a quench makes the blade mostly pearlite which is hard but brittle. By the time we temper it back to be soft enough to not chip or break then it's too soft to hold an edge well. If we quench fast enough to miss the nose then the steel is hard and tough enough that the temper is more for stress relief ,only dropping the hardness 2 points instead of 4-6.

 

[Phillip Patton]

I think maybe stingray is not communicating very well...
Let me ask this question:

If someone just wants to make ONE knife, would you still recommend that he buy 2 or 3 gallons of real quench oil, or use the ATF fluid he drained from his
transmission? Personally, for just one knife, I'd say go with the ATF.
But if someone if serious about knife making, and if they want to sell knives,
getting good quenching oil will help them do better right from the start.

My first 75 knives were just about all made from 1095, quenched in a mixture of biodiesel and used ATF. I didn't sell any of them (thank the Lord!) but some of them are still in use around my home. They're ugly, but they work.

When I first read Mr Fowlers books, I etched a lot of those old knives to see what it would tell me. Some very interesting results. Some of them were hard on the spine, soft on the edge, because I took too long to get to the quench, and the edge cooled down. Some of them had natural hamons, because the oil was too slow.
Thanks Ed, for that tip.

So anyway, I think the issue here is, if someone is just testing the waters, to see if he even wants to get into knifemaking, should he invest in good oil, or use something free? I say the free stuff. Then if he decides he likes it, get some good stuff.

My 2 cents.

 

[Karl B. Andersen]

Phillip, that was very well written.
Stingray, in your words,
"I'm a newb myself and am still learning and am open to any and all advice I can get to make my work as good as possible, but I do not have an unlimited budget either..."
You are open to any and all advice?
You're getting it! Get the right oil if you want to "make my work as good as possible".
You don't need an unlimited budget! With just a tiny bit of searchng on my part, I got 5 GALLONS! of Parks #50 for $39.00.
All of your time, aggravation of not getting the correct results, searching for alternative "recipes" and money spent on futile experiments will be saved simply by just getting the right stuff.

 

[Kevin R. Cashen]

Arrgg, I had determined to slip out to the shop now and not get mired any deeper in this pointlessness, but Mr. Patton has a way of engaging my better nature and reasonable side. Phillip you are correct that a guy could get a feel for things using ATF or hydraulic fluid (as opposed to many alternatives both these liquids have COOLING concerns in common), but it is far too common for folks not to look any deeper than the adequate results provided and then share that mediocrity with everyone they meet, after all we are proud of our perceived successes.

But now the above paragraph exists where I said ATF will work, and herein rests a serious problem. This forum is one of the first I visit anymore because it is a lonely beacon of reason in a field littered with misinformation, I am sure many others have to feel the same way, which lends considerable credibility to what is written here.

I once had a student who was taking notes as I showed him exactly how I did a normalizing cycle, I was using a scrap blade and after I was done I wanted to safely set the blade aside so I just dumped it in a bucket of water. We discussed a bit more and then called it a day. A month or so later I get a phone call from another knowledgeable smith who wanted to know if I was really teaching what he heard or if I had lost my mind. My student trusted my input so much that he took notes on EVERY action I took that day, so he had then shared with others eager to learn that Cashen finishes his normalizing by tossing the hot blade in a bucket of cold water .

This idea that any substance, from red head pee to bacon grease, will work fine for a quenchant is so heavily engrained in our field that giving an inch to admit that ATF may be adequate in a pinch could be heavily misused by those seriously wishing it to be true. With the number hungry knowledge seekers logging in to this site I cannot bring myself to say they can settle with an alternative without pointing out that there are much better ways. If we have people paying attention we have a responsibility to give them something more than what they turned from in order to listen.

Anyhow that is my motivation for even getting involved in this one, although I normally avoid “mystery steel” and “mystery quench” threads for the very reasons so self evident in this one.

With that being said the shop awaits and I have much better things to do today than smelling like dead horse spatter.

 

[polish avenger]

Uhhh, was that 5 gallons for $39 a lucky one-time deal or can anyone get in on that?
-Mark

 

[bodfish]

All of your time, aggravation of not getting the correct results, searching for alternative "recipes" and money spent on futile experiments will be saved simply by just getting the right stuff.

Ok, lots of good STUFF here So......let's get real specific, if we may.

Is this all true?

We want to cool the steel as fast as possible without cracking. IS this the goal?

And with the steels I use (O1, 1095, L6) will ONE commercial oil do it all?

(doesn't seem logical as 01 is an oil steel, while the other 2 are fast, right?).

I've heard L6 doesn't need a temper at all. So a slower quench to the right Rc might be fine?

If I'm on the right track, then it seems that obtaining the proper temps and soak times may be more important than the proper oil.........what say you?

AND, If I get file hard results (no matter what I use) and no cracks, then have I made it to the finish line?

 

[Chris Meyer]

... with the steels I use (O1, 1095, L6) will ONE commercial oil do it all?...

bodfish, since I've only been using Heat Bath/Park Metallurgical's oils, I can only speak for those. There are in fact different oils for different steels. (See the list at the bottom for Park's description of its Quenching Oils.)

Park's #50 Oil is for steels needing a very fast quench, 1095, 1084, W2, and the like.

Park's AAA is what I use for O1.

I've heard L6 doesn't need a temper at all. So a slower quench to the right Rc might be fine?

That seems like very bad advice. I suspect that it is a myth prompted by L-6's ability to somewhat air harden. Please note that I have not used L-6 myself, so you should double check with a knowledgeable user, like Kevin.

AND, If I get file hard results (no matter what I use) and no cracks, then have I made it to the finish line?

Unfortunately, NO. Fine pearlite will skate a file, but will make a lousy knife. You want as much martensite as possible, and then to temper it so it's less brittle.



From Park Metallurgical's website:

#50 QUENCH OIL Low viscosity quench oil that approaches water in quench speed, yet gives a more uniform, less severe quench than water. Recommended for open quench system operating below 120 deg F.

AAA QUENCH OIL The most popular, widely used quench oil. This patented accelerated quench oil provides a maximum, uniform cooling rate for austenitized steels, as well as clean, easily washed work when properly maintained.

400 QUENCH OIL Similar to AAA but contains extra reservoir of accelerator additive for use in situations where excessive consumption occurs.

420 QUENCH OIL A "medium hot" oil recommended for accelerated quenching operations in atmosphere furnaces from 180 to 300 deg F. Produces uniformly well hardened parts while holding distortion to a minimum.

MARQUENCH OIL M An accelerated quench oil designed for applications at 250-350 deg F. The use of this "hot" oil is commonly encountered in carburizing and carbonitriding furnaces or where parts are prone to distortion and cracking.

THERMO-QUENCH OIL A "hot" or "marquenching" oil offering excellent thermal stability, high flash point and fast quenching rate.

VACUUM QUENCH OIL For use in quenching in integral vacuum furnaces. Offers excellent quenching rate and thermal stability, good viscosity, and low volatility.

HIGH SPEED VACUUM QUENCH OIL Faster quench speed than Vacuum Quench Oil above, but otherwise very similar.

QUENCH OIL ACCELERATOR Blend of mineral oils containing a high percentage of the additive used to provide the high cooling rates of AAA. Transforms most ordinary quenching oils into "accelerated" oils where faster quench rates are desired, or to maintain the AAA quench speed after prolonged use of the oil.​

 

[stingray4540]

Thank you Mr. Patton. Sometimes it takes a third party to interperet, and I think you did so pretty well. Hopefully your interpretation will be better received.

Kbaknife: Would you care to share were you got your Parks #50? And is that what you paid including shipping? or did you get it locally?

 

[Darren Ellis]

Uhhh, was that 5 gallons for $39 a lucky one-time deal or can anyone get in on that?
-Mark

I suspect that's a one time deal, as that's much less than what I'm paying for it wholesale ordering 400 gallons at a time... Also, they just recently implemented a price increase of almost 35% due to petroleum prices...I haven't raised my prices...

-Darren

 

[Ed Fowler]

Bodfish: There is no simple answer, I have been working with one steel for over 20 years. I have one of the best equiped laboratories in the US to help me, we still have many questions, more than we will ever live long enough to answer.

The important thing is to keep asking questions and share your answers, some will appreciate it, some will critisize. This is a good thing!

 

[bodfish]

The important thing is to keep asking questions and share your answers, some will appreciate it, some will critisize. This is a good thing!

Well then...........here's what I "think" I know, my opinion if you will.

We want a good blade. We know that we have to raise the temp of the steel so that austenite forms, right? The higher you go above what is required, the larger the grain size. (bad, bad). Soak times enter into this equation, me thinks.

After that, you want to cool it down fast enough (depends on the alloy), so that we avoid the formation of pearlite (also bad bad).

When it cools fast enough, the austenite forms into martensite (good, good). Too fast, it cracks, too slow, pearlite forms. If we interrupt the quench at the point where martensite starts to form (we might call this Ms), AND the temp is now low enough that pearlite doesn't, and let it air cool, then maybe some of the lazier austenite will get a chance to transform into the good martensite.

Now this "might" even continue transforming, as it cools, past the summer temp of your shop. Some high alloy stuff may even still form some of the good martensite right on down into the sub=zero temps. (never tried this, though).
Let's call this Mf> The finish of the transformation.

After all this, a couple of cycles of tempering will relax what stresses it can, and leave you with the hardness/toughness you desire.

And...........all the rest (quench oils, oil temps, salts, robotic arms, and more), are just tools to fine tune the process....

AT least that's the assumptions I'm using for now

 

[Guy Thomas]

Well then...........here's what I "think" I know, my opinion if you will.

We want a good blade. We know that we have to raise the temp of the steel so that austenite forms, right? The higher you go above what is required, the larger the grain size. (bad, bad). Soak times enter into this equation, me thinks.

Increase in grain size is much more dependent on temperature than time. Long soaks at normal to low austenitizing temperatures are fine, however even short forays into higher temperatures cause rapid grain growth.

After that, you want to cool it down fast enough (depends on the alloy), so that we avoid the formation of pearlite (also bad bad).

When it cools fast enough, the austenite forms into martensite (good, good). Too fast, it cracks, too slow, pearlite forms. If we interrupt the quench at the point where martensite starts to form (we might call this Ms), AND the temp is now low enough that pearlite doesn't, and let it air cool, then maybe some of the lazier austenite will get a chance to transform into the good martensite.

No maybe about it, if you cool fast enough to get past the pearlite nose and on down to Ms, usually around 400 degrees F but varies in different steels, you will continue to form martensite if the steel is removed from the quench and allowed to cool to Mf.

Now this "might" even continue transforming, as it cools, past the summer temp of your shop. Some high alloy stuff may even still form some of the good martensite right on down into the sub=zero temps. (never tried this, though).
Let's call this Mf> The finish of the transformation..

Actually, lets not confuse terminology, Mf is a designated point arrived at by carefully controlled experiments in isothermal transformation. It's the point at which after Ms is passed a substantial portion, 90% or more of the austenite is transformed into martensite. Any transformations which take place after this are the result of tripping "retained" austenite into martensite by either tempering operations of all steels or sub-zero treatments of the richer alloys.

After all this, a couple of cycles of tempering will relax what stresses it can, and leave you with the hardness/toughness you desire.

And...........all the rest (quench oils, oil temps, salts, robotic arms, and more), are just tools to fine tune the process....

AT least that's the assumptions I'm using for now

A fair summation I think.