View Full Version : Leaf springs

04-22-2010, 09:41 PM
I have some leaf springs off of an F-350 that I acquired recently. The sheet I have on Junkyard steels says leaf springs can be either 1085 or 5160.

Is there a way to tell the difference between 1085 and 5160 without a metallurgy test? From what I gather they need to be handled differently, particularly quenching.

Just starting to understand the differences between steels. I've done some searching and there's information on the two steels but not how to tell one from the other, at least that I can find.

If it makes any difference the springs are off a newer model. I think it was at least a 99, probably newer.

Thanks for any help

04-22-2010, 10:25 PM
goodluck with the leaf springs, i'm using one right now from a coal mining buggy and it's a PITA to form the tip like Kevin Cashen shows :) I think i'm going to stick to round bar instead.

Doug Lester
04-22-2010, 11:07 PM
The sheet that you have on junkyard steel is only an educated guess. It could be one of several "spring" steel and it is possible that the manufacturer couldn't tell you for certain what they are made. One thing that you do know is that they are leaf springs so it's a usuable steel. If you have a good amount of steel then you will only have to work out the heat treatment once for as long as that lot lasts. If the springs have much wear you might run into the occasional problem with stress fractures. Like all mystery metal, you are going to have to work things out for yourself, unless you want to send it to a lab for identification.

I would assume that it is an oil quenching steel, just to be on the safe side. If it acts like it doesn't want to move well under the hammer at a cherry red then take it up to a brighter temp. To harden taking it to non-magnetic, give it a short soak for about a minute and quench. Then check it with a file. Temper it at 375 degrees or at least two two hour cycles and check the edge for proper hardness. If it chips out, regrind the edge and retemper 25 degrees higher and recheck. Continue until you have the edge that you want. If by chance the edge curles you will have to reharden then temper at 25 degrees less.

Doug Lester

04-23-2010, 06:18 PM
Thanks for the information Doug. Yes I've probably got close to 150 pounds of steel here. They are complete. So I should be able to make plenty of knives or plenty of mistakes. :)

Doug Lester
04-23-2010, 10:20 PM
DropPoint, if you're not making mistakes, you're not trying hard enough. You will make your own pile of knife shaped paperweights, just like the rest of us. Just remember that a mistake that you don't learn from is a mistake wasted.

Doug Lester

Dan Pierson
04-24-2010, 03:12 PM
If you've got 150 lbs and are sure it's all the same stuff, it's probably worth it to have a sample analyzed. Then you'll know what you're really dealing with and can adjust based on that knowledge.

04-24-2010, 04:43 PM
I was thinking of having it analyzed but I'm not sure of the cost. I'll have to check and see.

Thanks for the help.

Also was curious as to how to straighten the springs, heating I assume but not too much? Or just use the straightest sections and grind flat?

04-24-2010, 04:56 PM
You need to heat the springs to an orange color to remove the temper (annealing) that's already in them, and you can straighten them while they are hot. Not annealing the springs before working them will only make working them that much more difficult.

My spring knives are always 'users' and not art pieces. I heat to non-magnetic and quench in oil. Temper in the oven.

04-24-2010, 05:45 PM
Thanks Vaughn. I wondered about that. I cut off a small piece and tested with a file and it seemed very soft compared to the bolsters I've been working on. But I know next to nothing about steel so I'll do as you suggest.

I've worked wood before but knives is my first real venture into working steel.

Doug Lester
04-25-2010, 12:01 PM
If you are doing stock removal then you will deffinantly want to anneal the steel before working with it. It may seem soft now but annealing will make it softer still and extend the life of your grinding belts. If you are forging the steel then the temper will be removed when you heat the billet to work with it.

Doug Lester