Leaf Springs

Hi - I happened upon a bunch of leaf spring steel for £10 last year. I have cut a couple of blanks to make some large chef knives from it but I am having second thoughts due to the thickness of the steel.

It's about 6.5mm thick and although I have a forge and anvil, I am not sure whether it's worth even trying to thin this stuff out enough to be workable for kitchen knives. It will make lovely bushcrafters, skinners and so on but I think it might just be too much elbow grease for chefs.

Has anyone made kitchen knives from stock this thick before? Was it worthwhile?

I used to forge out integrals from 1" round steel. Purely by hand.
Whether it's worthwhile or not is up to you.

what you have is probably 5160(most common leaf spring material) which would make an ok heavy chopper but not ok kitchen knife.

While 5160 probably isn't the greatest choice, why wouldn't it make an "ok" kitchen knife? It's the most common choice for passing the ABS Journeyman bladesmith test, of which the first performace test is slicing free hanging rope. As quenched hardness should reach HRc 62 from what's found online.

Maybe bang for the buck for the time invested is not great if forging down 6.5 mm top kitchen knife thickness by hand. But everybody has different feelings on that probably.

Depends what kind of forging you want to do. I've seen a lot of guys on youtube who only forge rectangular stock into a knife profile and then start on grinding. I took one forging class last summer and there we started from 6.5mm bar and lengthened and broadened from there. If you want a knife 50mm tall I think a 20mm bar 6.5mm is about right if you use that method. Upside is you use a lot less steel and don't have to thin much on the grinder. Downside it is a lot more difficult than just the profiling. I'm pretty sure if I were to try it again without the instructor present I would **** up the first couple times. Hands still itching like crazy though to try it again.

You would be putting a great deal of effort / time & money on fuel to do nothing other than knock it thinner. I am 'time poor' so prefer to spend my forge time learning 'tips tangs and bevels' etc.

You would also have to take a lot of heats, which will increase the chance of decarbing the steel, and increase the chances of messing it up by forging too cold / overcooking it etc.

Why not forge a petty from a bit of the stock to give you a better feeling for 'is it worth the effort for a 10" blade' !

6.5mm isn’t that bad. Maybe grab a cutoff wheel and cut perpendicular to the length into small pieces.

6.5 mm to 3mm is really not a big deal at all if you have a proper forge that is getting the steel hot enough. You can also work on forging techniques that will increase efficiency of moving the metal such as using the horn of the anvil or a peen on a hammer. It is actually much easier to forge in a profile at that thickness as well because as the steel gets thinner it tends to bend more than move when forging the profile.

Good points.

JMJones said:

It is actually much easier to forge in a profile at that thickness as well because as the steel gets thinner it tends to bend more than move when forging the profile.

Click to expand...

That is sooo true. I wish the instructor explained that to us at the start of our forging class.