How to Weld Together a Copper Goblet - Kevin Caron

When we join him, Caron is welding the base to the stem of the copper goblet. The copper is red hot. He'd turned the parts of the goblet on his lathe a year ago, and just got tired of seeing it sitting around. He was using his Everlast POWERTIG 255 EXT TIG welder for another project and thought, "What the heck, let's crank it up to max and play with a little copper."

Caron says you have to have all that amperage when you're working with copper because it's a great heat sink. After all, conducting electricity is its job. That's why it makes great frying pans, etc. So you really have to hit it hard. Caron had the 255EXT's foot pedal the way to the floor with the machine set at 255 amps.

He tried using his little propane torch, but that didn't get it anywhere close to the temperature he needed. He thought about using his oxygen-acetylene unit, but didn't have enough hands while working alone.

He used the propane torch to heat it up a little, then use the TIG torch at 255 amps to heat it to welding temperature. Caron says copper acts a little like aluminum. It takes a lot of heat, and then all of a sudden you're welding.

As an example, Caron shows a piece of 1/4" copper plate he was using to set his settings. He tried welding with AC instead of DC to see what would happen and found out, "Don't do that."

He was welding along, playing with the pedal to figure out how much amperage he was going to need and how to control the puddle. He got right to the end and blew a hole through the copper plate. When the molten copper dropped through and hit the relatively cold steel table, it froze. It created a small pocket that Caron then filled in.

The copper Caron had welded looks nearly black because of the oxide that formed while he was welding it and the fact that it wasn't completely protected by the shielding gas. If he'd rinsed it in the sink while it was still red hot, the oxide would have washed right off.

Caron says he's a little handicapped, actually, because he doesn't have any tri-mix gas. He just has an argon-CO2 mix. If he had an argon, CO2 and helium mix, he'd have had almost double the "horsepower" to weld the copper - about 1.7% more amperage than is listed on the dial. He'd have a lot more amperage to get it hot quicker, control it better, and get a better weld.

On the goblet, he's trying to get a big enough fillet so he can go back to the lathe and turn it to get a nice, smooth even connection between the stem and the base. It would look - and actually be - machined. It would look like it was all one piece, better even than a beautiful weld.

Caron will then weld the bowl of the goblet to the stem. He needs to clamp it to make sure everything is straight and true, because he needs to turn it on the lathe to get those nice smooth connections and he doesn't want it wobbling.

Next Caron takes the copper to the sink and rinses it off. Steam rises, not dangerous fumes as if he were cooling some other metals, like bronze. Caron then uses the wire wheel to clean the base and stem.

Then Caron talks about what he uses for welding wire. He shows the heavy gauge copper wire, which is actually just repurposed Romex electrical wiring. He cut off a chunk, stripped off the insulation to give himself a nice, heavy gauge copper wire.

Finally, Caron shows the finished goblet.

At the end of the video, Caron learns a lesson of his own ....

[JerryRigEverything]

Great looking goblet! Keep up the good work!

[skyym]

Thank you for the information and demonstration. Thumbs up.

[AmericanThunder]

Cool video! I work with copper, making chimes and jewelry. I do gas weld it, but I dislike doing it, lol. And one tip to remove all that ugly firescale is to throw the piece into a mixture of white vinegar and salt for about 15 mins. The scale will just wipe off.

[slister]

how do i learn how to do work like this? I would like to make my own but I dont even know where to start.

[CharlesStruble]

Very cool.  Thanks guys!  Hey, I noticed you have the makings of a very serviceable mailbox by your sink there...

[floppychicken]

Very Cool... I can't seem to get enough heat out of my Miller DV 165 to do any 'real' copper welding, but found that I like the bronze brazed look much better anyway....  I think a Bronze braze around these copper pieces would look AWESOME and add a bit of a 'organic look' to the piece.  However, it defeats the purpose if you're looking for continuity, especially with copper match.  Anyway, nice job, will we see the finished product in the New year?  Cheers,

[colincoles]

Kevin, at the end you show a brass goblet not the copper one?

[geraldestes]

thnx kevin - cool project...the gas percentages, the source for pure copper and all, etc.

[tomherd]

Good video, as usual. I did see one thing that I would do differently. Use the full face shield you had hanging on the drill press next to the grinder. I have found that my wire wheels sometimes like to eject wires into shirt, pants, …. etc. I would like to keep you intact so you can make more videos.
Thanks, Tom

[Patroand]

I use Bronze BLU-4217406 from Liquid air to fil steel dovetail. My tig welder use 110v, Cer tungsten at 80-100 amps. Why do I produce sparks and fume ? The sound is louder than bacon frying. There is a lot of residue around the braze. 
Thanks and thanks for all your video.

[ArcsandSparks]

kevin its funny i welded some copper last week. i used rosebud preheat, straight helium, 12ga stripped Romex, 2% thoriated tungsten, DC straight polarity, lincoln precision tig 225. i hit it hard then back it off when every thing starts flowing. Romex was invented about 15 mile down the road in Rome, NY by the Rome cable company hence the name Romex

[garymorton]

What kind of finish do you suppose you'd get if you brushed it with flux paste while it was still hot?

[w]

If this trimix gas works so well with copper why not use it all the time? -expense or are there other reasons?

[ronbianca]

Hey Kevin! You can get bare, solid core, copper wire at an electrical supply store if you wish. Stay healthy.

[quietmale]

nice job but you should make 2 so you and the VOICE can enjoy a goblet of wine together

[fmarthur]

Kevin
Another fun and informative video
I like the part where you find out like the rest of us it's HOT
and like you said trimix is a great solution - but it's expensive and not everwhere
but there are different trimix's 
anyway do appreciate your insight and help 
Keep up the good work and the ability to find the HOT stuff
thx
Awful Arthur

[rimmersbryggeri]

I thought you brazed copper drinkware.. I saw them do that on some kind of how its made show.

[everlastgenerator]

You cannot use TriMix with TIG.  No CO2.  Only Ar or ArHe.  CO2 will burn up the tungsten in short order, so will 02.