Forge welding 15N20 into a usable thickness by hand?

[Geoff Flato]

Diesel, kerosene, and jet fuel are all quite similar. 1:1 mix of jet A and summer diesel is basically winter diesel.

 

[JTknives]

I thought I read on here aways back that diesel was not working for welding. I could be mistaken but it sounds familiar.

 

[AlaskanHunter]

I thought I read on here aways back that diesel was not working for welding. I could be mistaken but it sounds familiar.

That's the impression I got from digging through some of the old threads here and over at the ABS forums. The hypothesis was that the dyes in it were causing the problem, which is why I had the idea of using #1

I never asked earlier, but what size stock are you looking to get?
NJSB has it up to .130".

Champaloy/L-6 are also close steels to 15N20 ( added a tad of Cr, Mo, V). They make excellent tough blades. IIRC, a lot of ABS test knives are done with them.
http://www.zknives.com/knives/steels/steelgraph.php?nm=15N20,l6,champaloy&hrn=1&gm=0

.130 would probably be thick enough, but I have no money to spend on steel right now. My wife and I are in progress of buying a cabin/land to live in, so all my knifemaking money is going towards making it livable. I'm really excited about it all because I'll be able to set up a shop then! But I do have a good sized pile from JT in .070 and .090. I thought I would weld 2 pieces of the .090 together and then forge to the right thickness. Besides I've really been wanting to figure out this forge welding stuff. It seems like a good opportunity to knuckle down and learn it.
I never really thought about using L6 before, I had always written it off as too hard to forge HT with my skill level, and I'd rather not go through the trouble of sending out for HT unless I really need to. Is L6 fairly simple to HT? I've always assumed (yes, I know what they say about assuming anything) that it was too hard, but never really looked into it. It doesn't really change my spare cash for buying steel, but it may give me something to consider in the future.

 

[JTknives]

I personally think your best bet would just be to weld along the outside and seal up the inside from the air. But that's assuming you have a welder. A tig welder is best but I use a small underpowered mig welder. Being underpowered actually is not bad as it seams to just put the bead on the surface and not really get much penetration.

 

[AlaskanHunter]

I personally think your best bet would just be to weld along the outside and seal up the inside from the air. But that's assuming you have a welder. A tig welder is best but I use a small underpowered mig welder. Being underpowered actually is not bad as it seams to just put the bead on the surface and not really get much penetration.

I Have access to a wirefeed welder at my work. I's a mig welder, but set up on innerflux wire instead of using shielding gas. So I should turn down the voltage to get as shallow of a bead as I can, as long as that bead will hold through the first round of forgewelding, then grind it all off right? I'm pretty sure I don't want any chance of that welding bead making it into the final blade!

 

[JTknives]

My mig welder is also a flux core and works fine. Clean your steel really good first, I sand the surfaces and then stack in the vice. Use the vise to clamp the layers togather tight close to where your welding. Weld the one side and flip over to the other long side and clamp to hold that side togather then weld. Do the same for the ends and then your set. The only problem I thought would be a problem is if you had a gap between the layers and some of that flux got down inside that's why I clamp it tight. Yeah you don't need a deep penetrating weld. The weld is there to hold the billets togather and keep out the oxygen. Now funny story, I actually do a dry weld on my Damascus with out welding around each layer. I stack up my billet and run a few beads to hold it togather and put it in the forge. The forge is adjusted to be a very fuel rich "reducing" atmosphere. I did one billet where I did not want any welds on the outside so I wrapped it in stainless foil to hold it togather and it actually worked great. But I would not do this if I was using a hammer. Once you pull the billet out you don't have long befor oxygen finds its way into the layers and builds up scale. So this works best on a press. With this method your edges will normaly not weld all he way so a light fluxing after and it seals right up. Let me see if I can dig up a few pictures.

This is one that I welded with out any flux. Well I used a little flux but after the first weld.

Here is the no weld billet that I wrapped with foil. You can see the remains of the foil on the ends and top. I actually really like this way but you have to do more then one foil wrap. One layer won't hold up in the forge for very long and try and keep it out of the hop spot where the burner blasts right on it.

The reasion I did not want welds was becaus I was going straight from that to this and did not want to stop and bring the welds off.