Can you weld copper with your TIG welder?

I am making some TIG electrode holders out of 1/2" copper pipe. I had some pipe sitting around after taking out a bathroom in my home that was inexpertly and in-advisably installed, so I figured I had nothing to lose. I don't have a torch to sweat them, so I figured what the heck and I lit up on them to see if I could weld them. I had read a lot about how copper soaks up the heat and requires a lot of amps, but this stuff is so thin I figured it was worth a try.

I started at 160 amps and promptly blew a hole right through the pipe. I guess I have enough heat! Those who have worked with conductive metals like aluminum or copper won't be surprised to hear that there was a huge difference in behavior between when the metal was hot and when it was cold. When it was cold, I couldn't even get a puddle going at 100 amps, and then as soon as the puddle formed, it was huge and wanted to blow through. Once the metal heated up, though, around 90-100 amps was just right, for tacking anyway. I didn't have any filler, and I did want to produce a few usable pieces, so I played it safe and just tacked up. The torch switch, with fixed output controlled by the panel dial was perfect for this. If I had been using the pedal, it would have been very easy to either overheat the piece with too low an output, or overshoot and blow through. With the torch switch, I could hit the exact amperage required immediately. I suspect, however, that if I had been doing more than tacking, I would have really wanted the pedal's ability to back off the heat, because the behavior of the piece really changed a lot as it soaked up heat.

Anyway, the answer: yes! You probably can weld copper pipe with your TIG welder! Here are some pics:

Attachment 10555

Attachment 10556

Yes you can, Copper to steel & Copper to Brass or brass to steel is no problem you can use copper ground wire from romex or just buy some bare copper wire. I have also used 5% brazing alloy when tig welding to attach copper to 1018 cold rolled steel.

I am currently getting ready to make some belt buckles out of copper and brass sheet material using copper , brass and silver wire to tig with.

Quote:

---

Originally Posted by cbmkr

you can use copper ground wire from romex or just buy some bare copper wire.

---

Oh, that's clever. For critical stuff, I would question whether it was clean/pure enough, but for something like this, no problem. Best have a heavy glove on the hand holding the filler, 'cause it's gonna heat up!

Here's a picture of copper fittings welded with a ground wire as filler - from weldingweb...

That boy does good work.

Attachment 10557

This is interesting to me and I believe it has been discuessed before. Is there any worry about welding on the material without a resporator?

Quote:

---

Originally Posted by Jason

This is interesting to me and I believe it has been discuessed before. Is there any worry about welding on the material without a resporator?

---

Well, that's a good question. I don't know the answer for sure, but I have never heard of a problem. Then again, copper is not often welded, so maybe it's just not talked about much. I know that you can get zinc poisoning from welding on galvanized, and some of the chromium compounds that come from welding stainless are very carcinogenic, but I don't think copper is typically alloyed, and of course it's not usually coated either (e.g. with zinc) so I don't expect there would be an issue.

In theory you should always wear a respirator and or have good ventilation when welding. But for pure copper there is nothing particularly bad. It's brass where zinc is added to the copper that can boil out and give you some issues.
FWIW, with real low amperage you can sweat copper with a TIG torch, too. I ran out of gas one night and after fooling around with a heat gun I figured I would give TIG a try instead. It's just another heat source. Just keep the power low and the arc moving and it's not hard to heat copper pipe to the melting point of solder.

Quote:

---

Originally Posted by cbmkr

I am currently getting ready to make some belt buckles out of copper and brass sheet material using copper , brass and silver wire to tig with.

---

I'm sure I'm not the only one who wants to see photos of that project!

This might get me expelled, or banned, but I started using the copper-bond epoxy :) I've almost set too many fires working in tight places :)

Quote:

---

Originally Posted by jameslo

This might get me expelled, or banned, but I started using the copper-bond epoxy :) I've almost set too many fires working in tight places :)

---

I have yet to try those sharkbite fittings, but I hear you about burning things while sweating pipe. One thing is that the TIG was so focused and no flame so it was better in that regard. I see there are neat little induction heaters for pipe sweating without flame, too. Maybe I'm just too old skool to trust epoxy for that, yet. Although, the older I get, the less I'm concerned with how long things last. ;)

I've seen the shark bite things for PVC, and even have some, just waiting to use them to fix the next leak. I haven't seen the copper versions. Why in the world can't I invent simple stuff like that?

I've had good luck with epoxy. Never a leak, either at the time of the repair or later on.

I know what you mean about worrying about how long things last, now. Sometimes I'm not sure I'll outlive the usefulness of a wet paper plate.

Quote:

---

Originally Posted by Rambozo

In theory you should always wear a respirator and or have good ventilation when welding. But for pure copper there is nothing particularly bad. It's brass where zinc is added to the copper that can boil out and give you some issues.
FWIW, with real low amperage you can sweat copper with a TIG torch, too. I ran out of gas one night and after fooling around with a heat gun I figured I would give TIG a try instead. It's just another heat source. Just keep the power low and the arc moving and it's not hard to heat copper pipe to the melting point of solder.

---

Thats what I was thinking about....

Welding copper is fun, but it will tax your machine. It is such a good conductor that it sucks the heat away from your puddle, and your fill rod (Romex) wants to stick. I posted some practice pictures a while back. I'll see if I can drag them back up.

Here are the pictures, it was my first time working with copper... Definitely a learning experience!

http://img.tapatalk.com/d/13/08/18/3aduda4u.jpghttp://img.tapatalk.com/d/13/08/18/a3aza8y2.jpghttp://img.tapatalk.com/d/13/08/18/jezeda3e.jpg

What were your settings?

Unfortunately, I can not remember the settings, just that I was really pushing the welder (a synchro wave 350 I have at work) and I was using 12 awg Romex wire as my fill rod. I think I was up to about 220 amps. The entire piece would get glowing cherry red before the weld puddle would form.... Very interesting learning experience. Almost like welding aluminum, if the work piece gets too hot, the weld puddle starts to expand... Well copper does this too, just takes a LOT longer... I'd love to try this with a pulse freq at a much higher amp to try and keep the heat local.

I think I am going to have to pick up some extra copper to play with or find a copper project. I only use it to fill holes when I mig or pull heat in thin metal when welding.

Copper seems to weld nicely together autogenously, which lets you really pick up the travel speed and not get the overall workpiece as hot or oxidized. You've got to have enough current to do it. Thinner materials being welded also helps, and pulsing does too (if you have enough peak current to spare).

http://www.everlastgenerators.com/fo...copper-welding

Quote:

---

Originally Posted by jakeru

Copper seems to weld nicely together autogenously, which lets you really pick up the travel speed and not get the overall workpiece as hot or oxidized. You've got to have enough current to do it. Thinner materials being welded also helps, and pulsing does too (if you have enough peak current to spare).

http://www.everlastgenerators.com/fo...copper-welding

---

If Gwaltnak used non-pulsed amps of 220, pulsing peak amps would definitely need to be high to localize the heat.