Forge welding rebar

[lyuv]

I experienced several consecutive failures in forge welding knife billets. So I want to take a step back, and do some practice welds. The thing is, that other than blade steels (expensive and very hard to get here), I only have rebars.

I know this material is generaly considered "bad" for blacksmithing. How will it do for forge welding?

[pnut]

Can you find a leaf spring, coil spring, tie rod ends,pushrods, maybe even a stick shifter from a vehicle. There's a lot of steel in cars and trucks that will make decent knives. I wouldn't try practicing with rebar. Here it's not consistent so anything you might learn with one piece may not apply to the next one or even the next section of the same bar. I'm not sure if rebar is different where you're at though. It may be made to a specific alloy. 

My suggestion would be a coil or leaf spring. As Thomas Powers points out, if you cut a coil spring lengthwise  you have eight to twelve  pieces of the same material in each spring so when you figure out the heat treat it will be repeatable but I've heard people say that some springs don't like to weld to themselves. I haven't tried welding a leaf spring to itself but I haven't had too many problems welding it to low carbon steel. 

I don't know how much this has helped but someone who knows more than me will be along to give you better advice soon. 

Pnut

[ThomasPowers]

As it seems you are interested in billet welding for blades you really need to practice with blade making steels; otherwise you are not practicing.

What I play with is stacks of thrown out bandsaw blades---most machine shops go through them on a regular basis---and pallet strapping, also generally a free material. (The stuff that will snap easily when heated and quenched will help keep the carbon content up.)  The Ni in the band saw blade makes for good definition when etched.

It is tricky to do good welds with small thickness stock stacked up 20-25 layers; but the practice is good and you can use it for blades if you have a successful one.

[Shoshinjoe]

Awesome tip Thomas thank you

[lyuv]

Thanks. Thomas - your idea is good. However, I already spent a whole day going through most of the carpentry shops around, and could"nt get any band saw. Eventualy I found a tiny, dark antient shop, with an antient guy, who makes band saws manualy (!). He refused to sell me raw material. But in exchange for an hour of listening to stories of the old times, I received 2 meters. Sadly, It was only enough for 2 failed attempts.

Anyway - I can get cars coil springs, per PNUT's advice - do you (or anyone) know if, welding to itself, it's a reasonable simulation?

[pnut]

Cars have a few different types of steel suitable to making knives. I don't see why you couldn't make a billet from a couple different types.  I don't make billets. The only blade I've tried to make that wasn't  mono steel was a San Mai style weld so I don't think I can be of much help. Can you find any pallet strapping or the metal bands that hold loads of long items together for shipping. I seen some large metal straps holding loads on freight trains. I was almost hit with one that came loose when I was working at a train yard. They also have them at lots of factories that have a shipping receiving dept. might be a good source. I have noticed that a lot of pallets are banded with nylon now instead of metal if they are light enough. 

Pnut

[ThomasPowers]

Leaf or coil spring can be a bit fussy welding to itself, you could always put a bit of sheet metal in between as a buffer or even a piece of file. I grab old rusty hand saws at the scrapyard for when I need a buffer and would prefer it to be higher C. The big reason I like using bandsaw blade is the nickel content makes the patterns pop when etched.

I get mine also from METAL shops as well as wood shops and if they are bimetal and I want more C in the body I add in file as C donor. (Metal shops tend to go through sawblades faster too...)