heat treat with a torch

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Aug 1, 2009
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hello is it possible to heat treat with just a propane or O/E rig
(oxy accetaline) I have quite limited space have to work outside. this is my firat time making a knife. I have plenty of designs some tools but I want to get this going. I have been practicing grinding with just steel
I plan to start with A2 tool steel, is it better to get the precision ground and spend the extra money for a beginner ?
thanks for taking the time to read
charles
 
:) Let me try this one for a start. Yes, you can HT with propane or O/A and there are lots of books that will tell you how to do it. The heat treat will not be the best it can be. It may give you a serviceable blade.

If you try to build a raft from hand, it won't compare with the average bass boat - but it will probably float and you can catch a bass off it. Same idea.

A2 may not be the best choice for this start process. 1084 (or something similar) may be a bit more forgiving. The important thing is how you represent the product. It's great to say "This was my beginning - and I have grown from there." People get upset when someone claims more than they have accomplished.

Let us know how it goes. It may provide inspiration (or avoidance) for others.

Rob!
 
You can HT several steels with a torch, but A-2 isn't one of them. You will most likely ruin the blade. A-2 needs a HT oven and a protective foil wrap to do it properly.
I have done bare A-2 in the forge ,just for fun, with so-so results. A piece of 1070/1075/1080/1084 will be a much more likely candidate. O-1 would work, but you will be getting about half of what the steel can offer.

Filling out your profile will help us know where you live, so someone nearby might be able to offer some help.

Stacy
 
I would add 5160 to the torch HT list. But anything more complex especially the air hardening and all the stainless steels - NO !!
Even with the simple steels do some serious reading about HT before you attempt it.
 
Yep...that about sums it up! :) No air hardening (that also means no stainless steels) steels without better equipment. As for precision ground or not, if you can find precision ground in a 107X or 108X steel and are willing to spend the few extra dollars, go for it. The mill scale can be pretty tough on belts to remove if you're using a grinder. Other than that, there's no real advantage to PG over HR.

--nathan
 
I've made 8 knives total: 2 from O1 and 6 from 1084. All were HT'd with a torch until non-magnetic, held for a minute or two (mostly to get the entire edge non-mag.) and then quenched in 100-150 degree (I was told that 130 is a good temperature) canola oil. All of the blades got hard enough to skate a file, then they were tempered in my oven at about 400 degrees, and that's as far as I know about the hardness.

I can tell you that doing it this way can make a very usable knife, but I will upgrade to a forge/kiln sometime.
 
Prior to getting my Paragon HT oven I used torches to heat treat 01 and 440C. Some of the knives were not so good, but many including 440C did so well that they still out perform knives doen in the Paragon.

The trick with 440C is to heat up the blade and guess the temperature, bright orange hot is about right. Keep the torch moving and hold the temp for a half hour, then quench in oil. The big problem will be the build up of scale, and there will be lots of it! With that said, I made do using torches until I recieved my HT oven. Grinding belts are expencive, and the scale destroys belts in no time.
 
thank you. you sure are a friendly bunch of people. very nice.
now let me ask you this. what about using a standar BBQ grillwith wood charoal or bricquets? I would dearly love to get a H/T oven but not I can make sure I can do this (plus the funds are low). I buy metals from onlinemetals.com for all my other projects but I don't see and of the 1070 or 108 stuff you guys mentioned. where can I buy small amounts og this stuff?
BTW I can be found on facebook
charles anderson
look for the guy with anugly mug and a fedora
thanks
 
Hey Charles,

Skip the BBQ and google "one brick forge." It's cheap and fairly easy to do. That will get you moving in the right direction.
 
what is tks please

www.texasknife.com or texas knife supply !

In the past (back in the day when i didn't have a clue) I used to heat treat some 1/8" A2 in a coal pit/forge. The blade would get hard, but again, you can't really judge very well what the hell you are doing. A2 needs to be soaked at temperature from 1725-1800'F for approx 30 minutes to an hour or so. Being able to keep that temperature consistent with a torch or forge...well forge i don't know so much, but a torch, i don't think so !

You will also get quite a bit of decarb on the surface of the blade from doing it that way. A2 needs to be properly heat treated in a vacuum furnace (free of oxygen) or wrapped in stainless steel foil packets that protect the surface from being decarburized.

Precison ground costs more and in my mind, just looks better, but using the bottom of a contact wheel with a belt and some patience can get you some really nice finishes to smooth out unprecision ground stuff (which is cheaper!) If you don't plan to leave any flats on your blade much, precison ground isn't worth it as you grinder will take care of it fast !

If you're just goofing around and want to make a few knives from A2, you can get a nice hard sharp edge with a coal pit, but it will be inconsistent in its hardening.

Basically, don't spend your money on it precision ground or not if you're not gonna do it right. You can get steels which require much shorter soak times at temperature and end up with better results.
 
thank you. you sure are a friendly bunch of people. very nice.
now let me ask you this. what about using a standar BBQ grillwith wood charoal or bricquets? I would dearly love to get a H/T oven but not I can make sure I can do this (plus the funds are low). I buy metals from onlinemetals.com for all my other projects but I don't see and of the 1070 or 108 stuff you guys mentioned. where can I buy small amounts og this stuff?
BTW I can be found on facebook
charles anderson
look for the guy with anugly mug and a fedora
thanks

In my opinion a BBQ grill with charcoal is TOO BIG of an area to try to keep HOT. It will cost you a HELL of a lot of charcoal and your results would be much better with a 1,2 or 3 brick forge like someone else said. Propane is a lot cheaper than charcoal and doesn't produce much mess.

You can check out this video that JT is in on youtube to see a one brick forge. Very easy to make !

http://www.youtube.com/watch?v=SUVA40VOaic

only draw back is they eventually crack and you have to make another one.
 
thank you. you sure are a friendly bunch of people. very nice.
now let me ask you this. what about using a standar BBQ grillwith wood charoal or bricquets? I would dearly love to get a H/T oven but not I can make sure I can do this (plus the funds are low). I buy metals from onlinemetals.com for all my other projects but I don't see and of the 1070 or 108 stuff you guys mentioned. where can I buy small amounts og this stuff?
BTW I can be found on facebook
charles anderson
look for the guy with anugly mug and a fedora
thanks

Ok It is nice to have a HT oven. But I know you can use charcoal a Fan and something to hold your Charcoal. I have made many knives with charcoal fan and small BBQ styled pit made with dozen chicago bricks.
You can find a good supply of Knife steel from Jantz Supplies. Use 1075, 1080, 1095 or even Damascus.

1. Use Cowboy Charcoal or what is called Lump Charcoal. Kingfords has great cowboy charcoal. DON'T Use regular charcoal it leaves in purities in your steel.
2. You need something like a shallow pan that wont melt. I used a shallow
cast iron oval pan about 5x15 inches about 3/4 deep. Just something to hold charcoal.
3. You need to have a fan. I used a honeywell 8'' fan. that you can pick up at Walmart. Just something that force air over your charcoal. Something that make the coals Glow Bright.
4. A telescoping magnets.
5. You quench medium be it brine, oil or just water.

You can and I have HTed knives this way. You heat the blade to point that magnet does stick to steel. Then quench it in you medium.
Then clean is off real good. Take it up to kitchen put in the oven at 400 degree for 1 hour then let it cool with the oven then repeat a second time and if you like even a third time.
Yes it really is this simple. Don't make it harder than it is.

Feel free to contact me.


Knifemaking is about doing it. Just do it.
 
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Yes, a simple charcoal ( lump, not briquette) forge will work fine for simple carbon steels. Google "brake drum forge" to get several good and simple tutorials on how to make one cheap. It can literally be done with back yard adobe clay, a piece of pipe, and an old hair dryer, so the cost isn't an issue. The better the forge works,the easier it will be to get the HT done, so look at several types, and pick what you are able to build. If your abilities and budget allow it, building a simple propane forge will put you way ahead. A perfectly fine one can be built for less than $100. A coffee can forge can be built for about $20-30 and heated with a JTH-7 Bernzomatic torch, or a Turbo torch. Google "coffee can forge".

Another good idea would be to modify your profile to say where in Wisconsin you are. If another smith lives near you, he may invite you over to do the HT in his forge.

Sending stainless and air quenching blades out to TKS or other heat treaters is a good alternative,too.

Despite Bufford's advise, stainless steels ( 440, CPM154, ATS34, etc), and air cooling steels (A-2, D-2, etc.), should not be HT in an open forge or with a torch. They need to be heated to much higher temperatures than non-magnetic ( between 1750F and 1950F) and held at an even temperature for as long as 30 minutes. If done in an open flame the steel will be ruined. They require being isolated from oxygen by wrapping in a HT foil packet, ant the use of a HT oven.

For shade tree quenchants, try canola oil or peanut oil. A gallon is enough for most blades. Brine and water will work. but blade breakage and cracking will be a much higher risk.

Purchasing a gallon can of fast quench oil from a knife supplier will be a great step forward when you are ready to get more serious.

If you haven't read them, read all the stickies at the top of the forum page about hypereutectoid steel, eutectiod steel, and quenching. There is a lot of good info in all those posts.

Stacy
 
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