Modern leaf springs

Ptac157

Ptac157

Gold Member
Joined
Jul 23, 2013
Messages
164
Just wondering if anyone could fill me in on the quality of modern day leaf springs for large knife/machete making? Someone told me that they don't use 5160 steel anymore and the modern materials aren't as good. I have access to a lot of brand new leaf springs so any advice would be much appreciated
 
Modern leaf springs couple be anything from 5160, to 9260, or something like a 1055Mod. This means you don't know what the exact alloy is, and therefore you don't know what the heat treat is. A bar of 5160 from Aldo is cheap. Don't waste your time with unknown materials. Once you factor in the fuel to heat the spring to straighten it, you will have spent more than the bar of 5160.
 
They are made out of everything, and anything. Different alloys, composites. Who Knows? You could take one home and test it to see what you can do with it, or you could order some 5160, which is about the least expensive blade worthy steel known to man, Know what you have, and how to treat it. Seems like a small price to pay.
 
Another option is 80CRV2. It's a great steel when toughness is needed, and has a bit more carbon than 5160. L6 is another great option. 80CRV2 is part of the L2 spec. Not all L2 will be the same as 80CRV2, but it is in the L2 spec.

In other words, you have some great options that are relatively easy to heat treat, with a known heat treat process.
 
Ok. The reason I ask is because steel can be a hassle to get here (Australia) and where I work we sometimes do suspension upgrades on new 4wd's so the stock springs get removed and usually just thrown away If I don't put them aside. Thanks for the info everyone :)
 
You could try to find out who made the springs, and ask them what they use. Then it wouldn't be unknown steel. A long shot maybe, but wouldn't hurt anything to try.
 
As much of a cheapskate as I am, and since the new springs are free - I expect I'd use a few of them for trial blades. Working up forging technique, moving metal and learning. I'd heat treat the first one as if it were 5160 and see how that turns out. Depending on where you are in Aussie land, shipping could be quite expensive for ordering a good known steel.

Now, "IF" you could get good cheap blade steel as easy as we can here in USA..... well, I'd still start with mystery steel for learning forging technique.

Ken H>
 
If the company you work for makes their own aftermarket springs then their spring stock may be consistent, good quality stuff. Taking whatever came off the last vehicle they did will just get you random material. If anything I would find out the source of the new springs and see if they are of a usable alloy, and see if I could pick up the cutoffs and leftovers.
 
Are you going to forge the steel or just do stock removal? Because you have a lot of steel in a set of leaf springs, if you are going to forge, developing a method to evaluate the steel for different purposes could be to your benefit. If you are doing stock removal, then the cost and time involved may not justify their use. I have read a couple of posts from blacksmiths on how to evaluate unknown steel (different forum).
 
Since it sounds like you have tools to cut the springs up. I'd suggest:

Cut a piece up into a small test coupon and try to heat treat that piece. If it works, then your set. If not, then you know.
 
They are all new toyota leaf springs, I've made some enquiries and am waiting to hear back. In the meantime I have plenty to experiment with lol. Thanks everyone for the input, much appreciated!
 
Where are you in Oz? PM me and I'll give you the names of some local suppliers if you strike out with the specs.

If you are in Melbourne the Australian Knifemakers Guild Show will be held on the 2nd & 3rd of May. You will be able to buy supplies there.
 
Just an update for those who may be interested, I finally got around to having a piece of new toyota spring professionally heat treated. Started out at 50 rockwell and after quenching came out at 61. Looks like it might be of some use after all :)
 
Since the steel is free and you have trouble getting known steels, go on and forge it.
You could do a little HT testing, but i guess you should be able to have fun and some nice blade anyway treating it as a medium carbon deep hardening steel.
 
In the states, if you get Eagle brand leaf spring cutoff stock, as long as it's not a tapered leaf it's 5160 (this straight from the company rep). I have a deal with a local shop for raw cutoffs (generally for all-steel hawks,and JEST bolos)-I would think in Oz it'd be the same with any shop that does custom spring sets.
It's worth a call to the company rep-they can generally tell you exactly what you have if you're using end cutoffs.
 
We Yanks really are spoiled for good steel... I was about to suggest turning in all the springs as scrap metal and using the money to buy a couple bars of 1084 or 80CrV... but that may not be an option.

If you have several springs of uncertain provenance, you could always weld the whole mess together into a stack, then fold/pattern weld it several times into a fairly homogenous billet that would all HT the same, and look cool too. (I'm only half-kidding... that's a whole lot of work, but it could be done... )
 
I talked to a local spring shop, he said all of his new spring stock was 5160. He have me a few pieces and said I could come back when they had more. It hardend up fine, but I haven't used it all up, and still treated it as "I think this is 5160".
 
Here it's been normally 5160.Other parts of the world it's been 9260 though a better spring steel is 9260 with Vanadium. M-B truck springs were 5160mod . Take a piece , HT and test .
 
Here it's been normally 5160.Other parts of the world it's been 9260 though a better spring steel is 9260 with Vanadium. M-B truck springs were 5160mod . Take a piece , HT and test . The newer the spring the better as old ones may have stress micro-cracks or other problems .
 
You must log in or register to reply here.
Back
Top