bridging a gap with a stick welder

[Don A]

This is kinda hard to explain without pictures, but I was asked to weld an old axe head back together. The guy was striking the back of the axe like a wedge and it broke clear-thru... both sides of the eye... two pieces.

I told him that I would not weld it and guarantee it for use. He said that was OK; it was an old family axe and he was just going to re-handle it and retire it.

I'm using my Lincoln 225AC with 7018 rods.

I wire brushed everything to bright, ground both sides to an inward bevel, then clamped it in position. I put a good sized tack on either end of both cracks. I wanted them to be big enough to create a sort of dam for the puddle; to give me a good starting and stopping point.

Everything was going great until the end of the bead on the second crack. The material was thinner than the other side and I managed to blow out a small gap. I cleaned it up and tried to bridge the gap at a lower current, but only made it worse. It's not terrible; I figure a #2 pencil would fit in this half-circle gap.

So, is there any way that I can back the area with something sacrafical and get this area biult back up to where I can grind it back to its original shape?
The steel is less than 1/8" thick in this particular area, so I thought I'd better ask before I try something that only makes it worse.

Thanks,

Don

[unkle spike]

You could back it with copper and turn the amperage down, and just "dab" weld on it, clean it up between dabs until you have enough there to put a proper weld to it.

[HWooldridge]

Yes, you put a weld tab on the ends and weld off the part and onto that piece, then remove the excess with a saw. You can also fit a piece into the hole cold and weld that in place. In other words, saw or grind out to clean metal and file a matching piece to fit. Weld and grind to finish.

I can fill better with a 6011 because it's a fast freeze rod but 7018 will work if you are careful. You didn't mention rod diameter but 3/32" would be best if you can get that size.

[Jerry Miller]

6011 is a good rod as stated above .sometimes if i have a gap i will take a 7018 and knock the flux off and use it as a filler like when you gas weld I hope this helps

Edited April 4, 2009 by steve sells
clearity

[Jack Evers]

As Uncle Spike says, copper is a good backup. Aluminum will work but I prefer copper. I rarely have the copper bar I need, but I've usually got copper tubing around. Just flatten it and use it for backup.

[horseshoe182]

Yeah use the copper, i,ve used it many times and it works just great, like Jack said flattened copper tube/pipe will do. As for your welding job, I would mig it if you can, as its so easy ,quick, puts less heat into the job and is also low hydrogen too. If using a stick welder, I would go with a 2.4mm low hydrogen rod, at about 65 to 75amps. Weld big tacks at begginning and end of weld. Start weld and don,t stay to long in the middle of your small weave, so concentraet weld pool on the sides of the weld, so to speak. You could also do the opposite of a weave, run the weld along the sides of the joint annd it will eventually close up. One rule I have with filling gaps is, when you think you will get a hole, because it,s getting to hot, STOP, and let it cool down by itself, don,t quench it, and then go again. It,s not an easy job you have.

[Don A]

That's exactly why I spend so much time on Iforge...

Thanks gentlemen. Thank you very much.
I'll combine all of the advice given and have a go at it.

Don

[peacock]

tun it up on edge and do a vertical down. down welds have much less penatration. If you have never welde down try it a couple times on some sscrap hold your rod about level maybe 5% low on the rod holder end don't try to hold the puddle up if it wants to drip let it go . I teach this to my students and it seems to work well. Good luck.
Phil

Edited April 5, 2009 by peacock

[Mick]

OK let me preface this by saying that the best weld I ever did be it gas, stick or mig looks like cocky poo, but in my quest for more knowledge I came across this on a site tonight, (no I don't recall the site) however the advise was to fill a big gap using stick, feed a second rod into the arc like you would with filler rod on TIG. Made sense to me and might be worth a try. FWIW.

[Don A]

Glad y'all pulled this thread back to the top.

I finished the job and it worked great.

A combination of "all the above" (except the double stick thing... I was already done, but that sounds interesting).

The neatest trick was using that copper chiller as backing. I would have figured it would have burned the copper to smithereens, but it worked like a charm. I cold hammered a piece of 1/8" copper to fit the inside contour of the axe eye and it held the puddle right where I wanted it.

I appreciate all the input.

Don