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Doc Nickel
03-10-2006, 08:30 PM
I know I can TIG copper, and even TIG it to steel, but has anyone tried using a MIG on copper?

Really, I don't even need to lay a bead, I'd just need to be able to make a good, solid tack weld. That way I could fit parts easier- hold, close eyes, tack, rather than the three hands, one foot and helmet needed to tack with the TIG.

Yes, I know heat will be a problem due to the thermal conductivity of the copper, but the pices should be small and relatively thin.

And, I suppose I should ask, if it can be MIGged with some success, where might I find a roll of, say, .024" solid copper wire that I can fit through the machine with minimal rigamarole?

Doc.

torker
03-10-2006, 08:36 PM
Hmmm...good question Doc. I've never heard of migging copper but it wouldn't suprise me that it is possible.
Is there anyway you can fusion weld it with your tig torch (no filler)?
Could you allow a little extra material stickout to act as filler? I've done that before when working with very thin sheetmetal and tig.
Russ

Dawai
03-10-2006, 09:09 PM
Yes, it puts off nasty fumes.

Saw it done to copper bus in a power plant, a digital mig with 175 amps output.

They would not let me play, since I had not been certified there at Racoon mountain as a welder.

David

wierdscience
03-10-2006, 09:22 PM
I have never tried it,but-
http://www.mcmaster.com/

has silicon bronze weld wire designed for that application,checkout page# 3187,bottom of the page under the specialty wire section.

I have tried the 55-FC-0 hardfacing wire and it is excellent if you ever have a need for that.

Copper does tig excellent,thou it also takes more amperage than steel or stainless.I just use solid copper ground wire for filler,maybe not correct,but it works.

torker
03-10-2006, 09:26 PM
weird...that's what I use to tig copper with also. I have a little bit of old house wire left that I hoard for this. It's from the old tar and fabric(I think) coated wire that I stripped out of an old house I bought.
I have a devil of a time with some of the new wire. It doesn't seem as pure.

Tin Falcon
03-10-2006, 09:34 PM
Doc:
.030 ECuSi filler wire www.weldingdepot.com (http://www.weldingdepot.com)
Tin

wierdscience
03-10-2006, 09:47 PM
<font face="Verdana, Arial" size="2">Originally posted by torker:
weird...that's what I use to tig copper with also. I have a little bit of old house wire left that I hoard for this. It's from the old tar and fabric(I think) coated wire that I stripped out of an old house I bought.
I have a devil of a time with some of the new wire. It doesn't seem as pure.</font>

Ya,I noticed that too,seems like it will weld fine and then all the sudden pop a bubble.I did use some wire that was burnt out of a motor,it welded fine,maybe it was a different alloy or maybe the heat did it.

Weston Bye
03-10-2006, 10:00 PM
I don't know about welding with copper wire, but I do know that magnet wire - the stuff in motors and solenoids is nearly pure copper. A source of fairly heavy gauge wire would be from an automotive air conditioner clutch coil.

Wes

Doc Nickel
03-10-2006, 10:09 PM
Thanks for the links. I suppose I should have looked to see if the wire was available first- if it weren't, that might well have answered my question. http://bbs.homeshopmachinist.net//smile.gif

WeldingDepot has pure copper wire, but only at .035 and up. I'll be doing pretty thin sheetmetal (though to a thicker frame) so I'd want closer to .024". McMaster has the bronze in .024... the color would be different, but I suppose a tack wouldn't be bad, just to hold it securely enough to then hit it with the TIG...

I take it nobody's actually tried copper MIG? Is there any problem with galling or sticking to the copper gun tip? Do I need the serrated aluminum-type rollers for the feeder?

Doc.

wierdscience
03-10-2006, 10:26 PM
Doc,I haven't tried it,but the mig wire would have to be fairly stiff for it to feed through the liner otherwise it would birdnest in the feed section.

Shouldn't need the serrated rollers,but who knows.

I see your point on the copper tip,maybe go up a size or two on the tip,like an .035 or .042 for clearence kinda like on aluminum.

WJHartson
03-10-2006, 11:33 PM
You can mig copper, we did it at the Chalmette Works of Kaiser Aluminum. We welded Multipal copper straps to a 1" thick copper bar. Had a machine specially built for the job. If I remember correctly it was a 600 amp machine. The fumes were very bad comming off the weld. The entire process was automated. The welds were not beautiful but were very sound. The feed wire was much thicker that .023 maybe .060 and was specially made for us. These were the current carrying bars, called flex, used in the pot where the aluminum was smelted.

If you try this wear a respirator and have some kind of fume collection system. The fues will ake you sick quickly.

Joe

torker
03-10-2006, 11:45 PM
Joe...ditto on the respirator! I always use a North dual filter resp when welding anything off the wall.

Doc Nickel
03-11-2006, 02:24 AM
As I said, I'll just be tacking, then making the actual welds with the TIG. Sounds like it's feasible- copper takes more welder horsepower, but again, I'll be doing small pieces.

I'll have to spring for a roll of wire and try it...

Doc.