Forge welding and the handle came off!!!

J

jawilder

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Jun 27, 2006
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Last night I was trying my first attempt at making San Mai using a core of 3/16 1080 then 15n20 then 3/16 mild steel on the outsides. I sandwhiched it all together, wire welded, and left the 1080 in the 4' length to have a handle. While in the forge waiting to come to temp, about 10 minutes, the 3/16 1080 "handle" completely broke off at the joint of the billet :eek:

Not too much of a problem because I had the tongs handy. I got it all together and there are no seems after clening up and etching the edges... but did I get the steel WAY too HOT? I am hoping the 15n20 kept the carbon from migrating out of the 1080. I've heard of nickel foil doing that but don't know if 15n20 will.

I am certain that the 4' handle was way too long because about 8" of it had to be in the forge while heating and it got orange hot and bent from the weight of the length before it broke. Next time I'll shorten it down to about 2'

Jason
 
Try stacking the billet of even length pieces and welding a handle of scap tubing or rod to form the handle. You may have seriously overheated the section of lone 1080 that was outside the stack, bear in mind that the difference in mass affects how fast it heats, and if you were running the forge full out, could have taken it way too far.

I have welded handles break off from bad welds all the time, but a continuous piece of steel from the billet shouldn't break that way unless you got it crazy hot, and/or thinned it out from forging past the other layers.

Might want to scrap that section of the 1080 bar, the billet is probably fine, just thermal cycle as you would expect to.
 
javand said:
Might want to scrap that section of the 1080 bar, the billet is probably fine, just thermal cycle as you would expect to.
Click to expand...

That's exactly what I plan to do.

I have tried to weld rebar to the billet before but my cheap 110v flux core welder won't give me good enough welds for it... or at least I wasn't able to get good enough welds the last time I tried it.

In all fairness, as the 1080 handle would bow from the weight of the handle I would slightly bend it back while in the forge and I wonder if moving it back and forth about 3 times caused a stress in it. I don't care as much about the section of 1080 that broke off as much as I care about the integrity of the billet. Like you said its mass most likely protected it from over heating.
Jason
 
I think half inch square stock would make a better handle for that size billet. When making pattern welded billets, I use 3/4 inch square stock and after a few welds, they eventually weaken. Make sure to bevel the edges at the billet end of the handle, so you can get some penetration with your weld. -Doug
 
If you have or can get a gas system for your welder you will be amazed at how much better it will do. Your handles will still fall off after some hammering though.

Wayne Suhrbier
 
You'll also get a better penetrating weld with the mig if you heat the metal, thicker side, up with a torch or your forge first.
 
Thanks for the advice guys. I've never thought about preheating the metal first. Thanks Crex

This is only my 3rd billet. The first two came off because they were welded on. I just figured this would stay put since it was one single piece running throughout.

Thanks again.
Jason
 
I love it, a machine welded handle coming off during a forge weld OH NO! What to do? if only there was some way you could, weld it back on in the forge, you know, the forge you are forge welding in? LOL
 
Sam, maybe I didn't explain my situation well enough. the handle was not welded on with anything. What I was calling the handle was the through piece of 1080 that is the core of the san mai. the handle and core were all one piece and the heat from forge welding weakened the joint at the billet. I was not looking for ways to put it back on, only if I got the steel too hot
Jadon
 
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