Since I have received such a cordial invitation I guess I should chime in. <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//wink.gi f' class='bbc_emoticon' alt=';)' />

First, about the water; many work off from the hasty conclusion that since old swords, or even modern traditional Japanese blades were quenched in water that water must bring out some special qualities in steel. The problem is that the old blades, and very authentic modern Japanese blades, utilized bloomery steel or tamahagane, which are NOT the same material as modern steel. These old school steels are as close to simple iron/carbon alloying as you can get and are extremely shallow hardening compared to even our simplest modern steel. I speak from experience on this after working for years now with both modern alloys and my own smelted steel. Some of the simplest modern steels, e.g. 1075, 1084, 1095 are considerably more complex than the bloomery steels of the past and all contain some level of Manganese which greatly increases depth of hardening. It is this reason that water is actually a bit too fast for these steel s in knife size cross sections. Some would say that they achieve greater hardness from the shock of the water, but this extra hardness is most likely pure strain induced rather than purely martensitic in nature. My other concern is that those who have managed to navigate the treacherous waters of water with modern steel will almost universally say it requires low balling the soak temperature and time. Putting two and two together will tell you that it is the lack of full austenitic solution that accounts for the avoidance of distortion or cracking. When I add to this that I can easily achieve hardness in excess of 66 HRC in 1084 in a well engineered fast oil with thorough soak at precise temperatures, I should have to tell you that I have little use for water quenching in my shop, outside of my own thirst.

For 1084 and 5160, any number of quenchants will be suggested by many, and the latitude is a bit wider for the 5160 which has less demanding quench requirements than 1084. But for safety, health and liability reasons for this forum, if one chooses not to use a product engineered specifically for the task I would at least urge folks to stick with fresh and clean vegetable based oils. OF the two mentioned by Brion I would suggest the peanut oil for the 5160, it has a higher flash point and slower cooling curve, and the canola oil for the 1084 due to its accelerated quench rate. As pointed out by Brion, both of these oils should show a peak in thermal extraction after being heated to around 130F.

For heating the 1084 will give you the widest latitude of successful heating with anywhere from 1450F to 1500F. while the 5160 really should got to the 1500F to 1525F window in order to move its limited carbon throughout the material.

Thank you Kevin. I also do not have much use for water quenching in my shop. Just too many variables and what ifs. I use parks50 for my 1084 and peanut oil for my 5160. I must also say that these steels although fairly easy to heat treat still require good thermal cycling and annealing after forging and before quenching. I also sometimes do a stress relief cycle after rough grinding. Heating to 1200 to 1300 and slow cooling.

Again thanks Kevin and sorry for the cordial invite <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//smile.gi f' class='bbc_emoticon' alt=':)' /> .

Brion

I have a question... If I start using peanut oil instead of automatic transmission fluid. Would it hurt my quenchant terribly if I did mix a little automatic transmission fluid in (say a 5 peanut oil to 1 ATF) ratio to keep the peanut oil from getting rancid?

A question I have deals with hamons and edge quenching questions. Not how to do it, but rather, are these treatments beneficial to the blade quality?

Going too far down a path on this topic could take a few pages and definitely overtake this thread with another topic, so I will try to be brief… <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//biggrin.gi f' class='bbc_emoticon' alt=':D' />

Differential heat treating, hamons, can pretty much be placed alongside damascus steel in this area, in that the value is almost purely aesthetic, but with one exception, which could be good or bad depending on how you look at things. Differentially heat treated blades are by definition weaker in lateral strength, but are tougher in ultimate impact strength due to ductility. In common English this equates to a soft backed blade will bend very easily but will avoid snapping. Both types of blades will eventually snap under tensile strain at around the same place, but one will deform (stretch, bend etc…) considerably before reaching this point while the other will resist deforming right up the failure point.

One year at Ashokan we measured this and showed that the soft blade would require close to 8 times LESS force to bend than what was required to break the same piece at around 62 Rockwell. There are those would not like to accept this but they need to deny physical facts to do so. A soft backed blade is weaker in strength terms than a fully hardened blade, but the trade-off is that it will deform at a lower stress level to avoid breaking.

This should not be read as to say that the ABS test is no good, but rather to show the skills of the smith at creating different phases in the same blade with their control of heat. Most physical tests that I have taken in life had little resemblance to real world applications in order to focus on the skills of the one tested- try any of the tests one will do in Karate to get a new belt ranking in a true self-defense situation and you will see how impractical they are. The way I explain all of this is that a test blade bent to 90 degrees is the sign of a smith in control of heat, it is not a sign of a good blade.

After all of this you can see that physically the hamon blade is at best a wash, but aesthetically is where its true value rests, the effects can be quite beautiful.

Thank you, that answered my questions exactly. Now back to the topic <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//smile.gi f' class='bbc_emoticon' alt=':)' />. Teddy

In 2001, I was able to get a rather large volume of 1" square 5160 that was all from one melt, made in 1984.

Having such a large amount, I worked with it almost exclusively for about 2 years.

During this time I was able to get 10 gallons of Texaco A. I just opened my second five gallon this past week.

It's a very slow oil and works amazingly well for the deep hardening steels.

A couple makers we know take advantage of its properties when heat treating the deep hardening chromium steels like 5160 and 52100.

Alas, Texaco quit making it right about the time I acquired mine.

Which reminds me - one quenchant not mentioned for 5160 is vet grade mineral oil. Heated up a bit, I used it with excellent results on my 5160 until I was able to get the Texaco A.

The vet grade mineral oil, which is available at nearly any farm-type-store, eliminates LOTS of vegetable oil variables, and is available to us all.

Making sure it's "vet grade" is one way of determining purity and regularity.

Come to think of it, I just made two 5160 knives recently from my batch of old-stock steel.

I learned a couple things about 5160 early on:

1. Kevin is correct - not surprisingly.

2. The marginal carbon content, and the resultant chromium carbides that come during heat treating this steel, really require a good soak for the most benefit from 5160. That carbon really needs to get evenly distributed. With my stuff, I have come to enjoy a 10 minute soak - AT TEMP! - at 1515 in a pre-heated oven. (I have had limited success and disappointing results from trying to austenize 5160 in a forge.)

3. Get some Texaco A - or its equivalent.

Now, I've found Tex A to be the most beneficial of the oils I've used for my 5160. But it's no longer made - right?

Right.

However, there is a company in Perry, Ohio, called Great Lakes Oil Company that makes a Texaco A alternative they call "Quench A". And it's available in 5 gallon buckets.

I have not tried it. But I can tell you that I called a year or so ago and the price seemed very affordable. I've considered getting a few pails just to have in back-up in case one day they, too, stop making it.

Who knows.

Here's the description from their site: " GLOC QUENCH A is formulated from high quality paraffin base stocks which will resist oxidation. GLOC QUENCH A is oxidation inhibited to provide long bath life in conventional operations. The outstanding physical characteristics of this product coupled with the cost performance function ratio justify looking at replacing present quenching oil. GLOC QUENCH A is recommended for conventional quenching of ferrous metals at bath temperatures up to 150*F."

http://www.greatlake...05#Quench%20Oil

This is kind of related. A friend kindly gave me some spring steel off of an old (1950's) tractor with the request I make a knife out of it for her. My first thought was to to use something known and tell her I used it but instead I thought I'd ask. Any thoughts on tempering and heat treating old spring steel. Do the same rules apply as 1084?

Thanks

I've recently heard about taking the steel to 1650 for the carbides, then normalizing. Is this another internet rumor or is their something to it?

Edward, the steel could be 5160, could be 9260, could be 6150, you see what I am getting at. I would go ahead and make a blade out of it, heat treat it like it was 5160 and test it to see how it does. Check for edge chips, rolling, etc. I usually draw 5160 at 400 degrees for two hours and repeat for tempering.

Jimmy, for 5160 and 1084, I do a normalize at 1600 then air cool, then 1500 and air cool, then a sub-critical anneal at 1250. I have not seen the 1650. What steel were they referring to? And what were the circumstances?

Brion

|quoted:

Edward, the steel could be 5160, could be 9260, could be 6150, you see what I am getting at. I would go ahead and make a blade out of it, heat treat it like it was 5160 and test it to see how it does. Check for edge chips, rolling, etc. I usually draw 5160 at 400 degrees for two hours and repeat for tempering.

Jimmy, for 5160 and 1084, I do a normalize at 1600 then air cool, then 1500 and air cool, then a sub-critical anneal at 1250. I have not seen the 1650. What steel were they referring to? And what were the circumstances?

Brion

I heard it was for W2, O1, L6 the tool steels.

I am a new maker that is using 1084. I have a couple of ovens (left over from another life) and they are both programmable. My questions are:

1. In normalizing, can I program a routine that will allow me to take it up to 1600, stop and let it cool for 2 hrs, then take it back to 1500 and let it cool for 2 hours, and then take it up to 1200 and stop, letting the blade cool in the oven?

2. What program should I set up for hardening, the ramp and holding time till I quench?

3. Can I set up a program to temper the blades and, if so, what should it be?

4. Is it easier to use a torch and watch for color as I will only be doing 2-3 blades at a time?

As always TIA...Teddy

|quoted:

Going too far down a path on this topic could take a few pages and definitely overtake this thread with another topic, so I will try to be brief… <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//biggrin.gi f' class='bbc_emoticon' alt=':D' />

Differential heat treating, hamons, can pretty much be placed alongside damascus steel in this area, in that the value is almost purely aesthetic, but with one exception, which could be good or bad depending on how you look at things. Differentially heat treated blades are by definition weaker in lateral strength, but are tougher in ultimate impact strength due to ductility. In common English this equates to a soft backed blade will bend very easily but will avoid snapping. Both types of blades will eventually snap under tensile strain at around the same place, but one will deform (stretch, bend etc…) considerably before reaching this point while the other will resist deforming right up the failure point.

One year at Ashokan we measured this and showed that the soft blade would require close to 8 times LESS force to bend than what was required to break the same piece at around 62 Rockwell. There are those would not like to accept this but they need to deny physical facts to do so. A soft backed blade is weaker in strength terms than a fully hardened blade, but the trade-off is that it will deform at a lower stress level to avoid breaking.

This should not be read as to say that the ABS test is no good, but rather to show the skills of the smith at creating different phases in the same blade with their control of heat. Most physical tests that I have taken in life had little resemblance to real world applications in order to focus on the skills of the one tested- try any of the tests one will do in Karate to get a new belt ranking in a true self-defense situation and you will see how impractical they are. The way I explain all of this is that a test blade bent to 90 degrees is the sign of a smith in control of heat, it is not a sign of a good blade.

After all of this you can see that physically the hamon blade is at best a wash, but aesthetically is where its true value rests, the effects can be quite beautiful.

That depends on the dojo and standards. <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//wink.gi f' class='bbc_emoticon' alt=';)' />

|quoted:

That depends on the dojo and standards. <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//wink.gi f' class='bbc_emoticon' alt=';)' />

OK, let me be more specific. Forms (katas) are an excellent tool to allow a Sensei to see, under controlled circumstances, how well a student has learned stances and techniques, but a form will only get you a sound beating on the street. I see the ABS bend test very much the same as a form- a single exercise where a student can display their mastery of several specific techniques in a way that is easily observed and judged, but not necessarily the best route in everyday application. Making a good knife involves the ability to adapt and blend any of those skills together into something that is more useful in everyday use which will seldom, if ever, resemble the testing circumstances.