leaf spring identification

strahd71

strahd71

Joined
Jan 26, 2006
Messages
784
first let me say that i agree with all of the previous threads about mystery steels vs using known steels. known steels is the way to go, so no lecture needed on that.

but what if you do come accrossed something like an old leaf spring for free and you want to try it out for fun, is there a way to determine what steel it is? is there a way to look up a particular make and model car/truck and find out what was used for steel on the leaf spring?

thanks guys

jake
 
read up on sparks. you can kind of guesstimate what kind of steel it could be by what color, kind of tails, and shape of the spark. not very acuratly i don't believe, but you can tell if it has enough carbon to work as a knife or a letter opener.
 
metaltest, ask for blaine, i can't find the number but i think the number is online somewhere. $25 per sample, fast, they're awesome! I started using them because not all suppliers can be trusted to deliver the steel they say they will...
 
25 bucks would buy you quite a pile of 5160 if that's what you're looking for..... I've personally tested quite a few leaf springs for myself and others, and all have been 5160. I'M NOT SAYING THEY ALL ARE but I sure haven't ever found one that wasn't...
Matt Doyle
 
good point! even if it's not 5160 the heat treatment procedure is likely pretty close
 
so if they almost are always 5160, why arent they advocated for more? i mean i understand that there might be some out there that are something different. in other posts/threads alot of guys were really down on the use of leaf springs but yet in alot of books and the tim livley video it is the go to steel. its kind of strange to me.

jake
 
I don't think anyone is really down on using old leaf springs. They are down on using mystery metal. If I wanted a bunch of 5160 for forging I would go find a set of old truck springs, either send in a piece to have analyzed or forge a knife up, HT it like 5160, and then test it out. If you only want a couple knifes or have one spring leaf its probably better to just get a piece of flat bar. The mystery steel thing comes form people asking about lawn mower blades, bed frame, axle shafts, files and springs that they don't have a clue about. The steel is actually the cheapest part. Unless you are getting enough of to really know what you have and what you are doing, it is far better to start with a known steel.
 
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I'm down on the fact that I forged 5 blades from some wonderful "5160" leaf springs then found all these lovely stress cracks in the almost finished blade. You don't know what was done to the steel before you got it. I'm not 100% sure but I'm fairly sure that Aldo and the other steel suppliers I use haven't stressed my barstock very much beforehand. :p Although the steel may be stressed from Aldo talking to it while packaging, that's a different story though :D
 
I would say heat treat some peices and test them first, than play around with a few edge profiles on a simple peice and see if it preforms to your standard. I have been leaning to higher carbon, like 1075, and 1080 lately, it seems to stand up to bone better at a shallow angle than the springs steel I have been using.
 
my first 4 wheel drive was a 87 suburban ( i loved that thing). it died and has been parted out some. i've been thinking about yanking the leaf springs out of it before sending it to the junk yard. do you guys think its worth it? money is pretty tight, and again i understand that "known" steel is the best, but there is alot of steel in two sets of leaf springs.

thanks again

jake
 
Like has been mentioned stress cracks in use springs are the biggest problem, at least for me. I used them for years until I figure out that the cost of materials and aggravation caused by getting to the HT or worse to finish sanding and finding all those little spiderwebs in the blade. For $25-$30 you can get enough new 5160 to make 10-20 blades. More if you forge. Also if you get the material tested just make sure you have enough to make it worth the $$. It is up to you if it is worth it, we just provide our experiences. The main thing is have fun.
 
it's true you can get a fair bit of 5160 for 25 bucks, but if they send you something that's not 5160 yer gonna end up having it analyzed anyway (speaking from experience)

I get leaf spring sets , a pair is probably 150 pounds...

I dunno, have fun, make blades the way you want!
 
About the stress cracks a couple of you guys have found... can these be eliminated with several normalizing cycles? I'm sure you probably did that to your blades but, just thought I'd ask anyway.
 
DustinHall said:
About the stress cracks a couple of you guys have found... can these be eliminated with several normalizing cycles? I'm sure you probably did that to your blades but, just thought I'd ask anyway.
Click to expand...

No, Stress cracks are not repairable. Unfortunately many times they are not visible until after HT and you are doing your final polish.
 
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