Can anyone tell me the proccess to tig copper?

Date 03-29-2007 18:36

I have welded quite a bit of .060 copper, never used preheat. Argon (kind of heavy flow worked better for me, around 25cfm), lanthanated tungsten ground to a fine point, and crank the amperage up a bit. If you want it to come out pretty, set up a jig and purge the backside. I have never welded thicker copper, but the preheat sounds like a good idea, especially if you're having trouble holding a puddle.

By welderwv (*)

Date 03-29-2007 19:07

Copper that thick definitely needs preheat and the temp sounds right. If you are using flame to preheat it should have a rainbow look right after you remove the flame. Purge the pipe with argon (3-5 psi) but shield with helium. Push in a little more filler rod than seems right and if you have to stop keep the heat on it. Start the arc on the side of the bevel and work into the groove and stop the weld out of the groove and onto the bevel making sure not to leave a crater. If your welding in the flat position crank your shielding gas up to 50-60 as helium rises away from the weld. Good luck!

By Bill M

Date 04-02-2007 15:47

I have had luck using GMAW process with this Copr-Trode product from Ampco Metals. I think it is available in GTAW electrode as well, but never used it.

producthttp://www.ampcometal.com/common/datasheets/ampco_copr_trode_.pdf

By Sourdough (****)

Date 04-18-2007 00:23

Try propane, instead of acetylene for your pre heat.

By Tommyjoking (****)

Date 05-12-2007 10:11 Edited 05-12-2007 10:15

I have never Gtaw copper before....

I would like to learn good setup and technique...this could be great for building some fixtures...especially for stainless!!

So anyone with some good basic knowledge please post here!!!! I cannot imagine thiorated tungsten holding up on copper....

can you get decent results with %100 argon?? Or is helium a must? Closest I got to doing this was some bronze at one time...it smoked like all get out but it welded pretty.

By Lawrence (*****)

Date 05-12-2007 13:58

Tommy,

If you are talking about constructing argon backup fixtures for argon purge of various stainless applications, and made out of sheet copper (up to 1/8) you will have no trouble with GTAW, Argon, 1/16 thorium and a variety of fillers.

We usually used 0.063 copper sheet for the top piece (pre-drill your holes before you fabricate) and 304 or 321 for the sides and back.

The best fillers for these has proven to be Hastelloy W, but 347 will also do fine and I have even used bronze braze rod in a pinch. (though you would not want the welded bronze to contact your stainless melt thru.)

For work with PH Stainless (ie inco 718) or high tungsten/cobalt alloys like Haynes 25 or 188 you will want to chrome plate your fixture after compleation in order to keep the copper from migrating at the hot contact points.

By Tommyjoking (****)

Date 05-12-2007 19:36

Thank you Lawerence.

I have got plenty of 347 lying around as that is our primary filler...most of our stainless work is on 321 sheet and tubing. LOL I was wondering if I would be trying to cut strips of copper to use for filler LOL!!! Thats great I have an ample supply of copper since it gets used on the planes quite often....plenty of welds where I clamp copper plates in for backing strips and to prevent warpage issues. Now I can just build fixtures to put the parts in...this will save me some time and headaches THX

Tommy

By Tommyjoking (****)

Date 05-18-2007 08:30

Lawerence

Worked just dandy...TYVM!!!!!!