Knife blade hardining.

[Lin Rhea]

Hey Karl! Good to see you here. I heard you were a tradbow hunter. Too bad you cant come to Curtis' place with us.  

Guys, Better listen up, cause this guy is one of the best.
                                 Lin

[kbaknife]

Hey, Lin. I'm sorry I can't make it as well. Breaks my heart! I mean that.
I'm knee deep in sweat right now getting ready for my JS applicant knives. Does this mean I'm not gonna sleep for the next 4 months?
Anyway, I read that thread and just had to jump in, give a few basics to start and leave out all the fancy words.
Correct any errors! I make plenty of 'em!
About 1/2 the time I figure if you follow me you'll end up lost anyway.
You guys have fun without me.
I'll expect a full report.

[tippit]

Karl,  Thanks for posting.  Most of us are just hunters trying to make some sharp tools.  Nice to have some pros stop by...tippit

[sticshooter]

Hey loyd been making any knives?<><

[Doug Campbell]

Hey Karl, thanks for the help, like Doc says, it's great getting some Pros on here. First Lin now you, cool! Several of us have been tinkering for years and turn out some decent stuff but there's always plenty to learn!      

[Hooked]

Karl,
when you are dealing with old saw blades and files, or even new saw blades and files, how do you figure out what type of steel it is?

[loyd]

go up 6 posts , he tells you how. loyd

[kbaknife]

I don't use any un-known steel.
As a professional knifemaker, it's of the utmost importance to me that my heat treating processes are specific to the steel I'm using so I am confident I will achieve the desired results.
Even the non-pro should just use known steel.
You file and grind and beat and bend and cut and drill and sand and sand and sand some more.
Now, you go to heat treat and not know what steel you have? All that work for nothing?
Buying a bar of known steel and using the industry standard method of heat treating is always the simplest way to go.

[robtattoo]

Well said Karl! An 18" length of 1/8"x2" 01 steel really isn't expensive. It's very easy to work & has a HT cycle that is a cinch to do. It makes excellent knives too!  

[Hooked]

Thanks for pointing that out, Loyd, but he didn't actually answer my question in that post.  He does answers it two posts up that he just doesn't use an unknown steel.

The reason I ask is I am wanting to make my first knife and I will have two old 26" sawmill blades and a new one, plus some new nicholson files.  Are there any markings or engravings on the blades that will give you an idea of the type of steel?

If not I guess I just need to experiment and see how hard or soft after heating to demagnetization and cooling.

By the way, thanks for your posts, Karl!

[sticshooter]

Old sawmill blades are most likely L6. How old are they? If your aiming at a knife to use that will hold a decent edge for hunting  them sawmill blades will work great. I love sawmill blades for knives ... they have soul and character.<><

[Hooked]

Sticshooter,
I have not received them yet.  Bought two old ones and a new one off an auction website.  Beginning to wonder if i am gonna receive them.  When I get them I will take pics and post them.  Maybe ya'll can help me figure out if they are L6 or not.

[robtattoo]

Hooked, the only way you'll ever know for certain that you've got L6 steel is if you BUY L6 steel. There are so many different steel compositions out there, you'll never, ever tell by looking what you've got.
If you're serious about making a good, working blade, buy some good quality steel to start with. For price you've paid for the 3 mystery saw-blades, I reckon you could've bought a good amount of 01. A known & trusted carbon steel.

[loyd]

http://gbrannon.bizhat.com/old.htm#folders               lots of info here. loyd

[kbaknife]

Depending on how serious you are about using this steel, and it appears you are, I just a post on another site where you can get it an analysis for 40 bucks or something like that.
If you want that info, I can probably dig it up for you.

[sticshooter]

Very true only way to be 100% sure is to buy L6 steel. Most old sawmill blades were L6. If they made big sawmill blade to cut timber I just figure it must be some good steel. Now I am talking old blades not new blades like table saws. Kinda hard to believe they would make a sawmill blade out of junk steel. I am no pro but I have some knives here that I made from sawmill blade steel. I chopped all kinds of branchs and hacked on some frozen osage and they are still more then sharp enough to do what they are intended to do.JMHO<><

[Jeremy]

The only thing with using 'junkyard steels' is you have to be willing to sacrifice a knife or two.

If you can harden a test piece like was described earlier, go ahead and make a knife.  After you quench it, draw the temper back at around 350 degrees, put an edge on it and abuse the knife.  Hack away on a 2x4 and check the edge - if it chipped the blade is still too hard and brittle, if it bent it's too soft.  The first problem is easily fixed by tempering at a higher temp (say 400) the latter problem means the knife needs to be normalized, rehardened and tempered at a lower temp.

If there are no problems with the blade after chopping on a 2x4 do the brass rod test Rob described somewhere.  On a properly tempered knife the edge will not chip, crack or be permanently deformed.  There are some exceptions to that test however (you can get away with a harder edge on a small knife that won't see hard use - like a small caper or a neck knife).

The majority of common steels you'll come across that'll make a decent knife can be quenched in oil - most any oil actually.  I've been using 1095 which has a pretty 'hard nose' for a simple steel (you need to drop it's temp quick for it to harden) and if you look at its spec sheet, it's listed as a water-hardening steel.  I'm quenching in corn oil and I *know* it's working well.  Used motor oil didn't seem to work as well - it still hardened, but the quenched steel didn't seem quite as hard.  Water worked extremely well, but if you (being ME) overheated the steel even slightly there was a good chance the blade would crack.

Though I mostly use known steels, I have to agree with Frank.  Using reclaimed steels (resurrected   ) appeals to my, uh, frugal nature and the blades do have something special about them.

Here's a plug for Frank's knives:
I have one of his sawmill knives.  The first thing I did with it was put a scary sharp edge on it and hack most of the way through a doug fir 2x4.  It still shaved hair after and there was no damage to the edge.  The brass rod didn't phase it either.  Would it have passed the ABS JS test - well, no, but it certainly wouldn't be due to edge retention.  :D

[Jeremy]

I meant to add that where the proper quenching oils that kbaknife mentioned earlier really come into play is in industry where they are heat treating a large mass of steel.  
For a relatively thin blade made out of the simple steels (10xx series) and simpler alloys (5160, L6, O1 etc) you can use, and have confidence in, a quenching medium you find at your local grocery store  
Even the manufacturers of many of the (good) high carbon damascus steels these days are recommending quenching in a veggie oil.

[ArcticArcher]

Have been watching this thread for a few days.  I've got most of my work area set up this weekend, bandsaw, drill press, belt/disc sander, vise, etc set up.  

Jeremy has graciously sent me some kiln brick.  Propane torch purchased.

I am looking at getting some old saw blades to try. But, after looking at this thread not sure what to do.

So the next question is where does a person get the L6 steel or other types of steel to do this.  

Nick

[Jeremy]

Jantz Supply  
  Texas Knife

Texas Knife has O1, 1080, 1095 and 5160.
Jantz has 1095 and O1

All will make a good knife.