Welding Copper

[james gonzalez]

As far as the copper welding goes, I just went down to the welding shop and bought copper filler rod.
I am sure I could have used bits of scrap but I like visiting the welding shop. They might have to special order it in your area.
I did not particularly like the way it flowed, But the final weld held up well during the raising process despite the fact that I am a fair to middling tig welder at best.
I did have to do a little pinhole filling at the end there.
Maybe try using a thick sacrificial plate next to where you want to make the weld. You can start the arc there and have time to look around and adjust the heat with the pedal before moving over to the thin stuff.

[evfreek]

Hi James. Thanks for the tip. And others about the flux. The copper fused well without flux. I like the idea about the nearby plate, or just a sacrificial welding table like HWooldridge's (I just bought one of those; if it gets goofed up, I will just get another.) I used scrap Romex as filler. It seems to work. The key for me was to keep the bundle of strands together (with another copper wire). If one gets loose, it is like the weak animal which falls behind. It gets eaten by the mountain lion

My welder does not have a foot pedal. I really need to get one. Maybe that's my next project. Or is it a guillotine tool. Or is it a new slitter, or shear or ...

[evfreek]

Here are some pics of the bracelet:

[Dr Dean]

Hey Evfreak looking good. What do you have for a welder? I might be able to help you out with the foot pedal issue.

[evfreek]

Hi Dr. Dean. Thanks for the compliment. My buddy who is into small stuff turned me on to this design. He swore off the big stuff after I passed off a 7/8" S-7 bar to him to break down into a knife.

The welder I used to do the ends of the bracelet is my homemade microwave oven welder. It uses the frame, rewound transformer, bypass capacitor, fan and plug from the oven. I "borrowed" an arc starter from a real TIG welder.

I have a paper bag containing a high current isolated triac, a diac, and a sheet aluminum heatsink. I need to fab up a foot pedal. Right now, I am working out the bang-bang to make sure I don't skip cycle or glitch. Also, I need to size the potentiometer, since a lot of these designs sink a lot of power (like the Miller pedal).

[Dr Dean]

Wow man you are way more ambitious than I am. Cool to hear about something like that working out for you. How about some pictures?
I have a fingertip control with my tig torch. One thing that I noticed is it's very difficult to actually change the amperage setting when welding. I'm saving for a foot pedal.

[evfreek]

Hi Dr. Dean. Here are the pics you requested . The arc starter is not homemade, but the welder is made out of an old microwave oven. GE Spacesaver, I believe

[Dr Dean]

Oh my, that makes me wonder if Dr Suess was on the design team.

[evfreek]

Hi Dr. Dean. Dr. Seuss is pretty funny, but I wouldn't trust him for building electronics equipment

I guess that I need to put a front panel and terminal block on that thing. But, if you are looking at it and trying to decide, decent panel or copper bracelet, the bracelet wins. I think that the next thing it is calling out for is a foot pedal. I just bought a bench shear. It works great and I look forward to using it. Maybe this will be good for fabbing a foot pedal. Just some string and a little slide. Weld it up with the homemade TIG. Should be good. I really miss the foot pedal on thin stuff, so that might come before the lugs and decent cables. Good thing I'm in no hurry