Copper welding backer

[rslaback]

I've come to the realization that I need a good piece of copper to use to back up welds when filling holes and the like. It seems that most guys have somewhere in their lives come across a thick hunk of copper and snagged it for this purpose. I have not. If I were to strategically scrap for one, where would you suggest I look?

 

[DGersic]

I just use a scrap of copper pipe and hammer it to shape as needed. Menards has an infinite supply.

 

[The Cobbler]

a lot can be done with a flattened pc of copper pipe. also a copper cap on the end of a pipe
I've looked for a pc of solid copper for quite a while too and never been successful, they're out there, just nothing that I've seen

 

[rsanter]

I use many things.
They make a nice copper spoon with a handle.
I also have a couple of copper buss bars
Then there is the magnetic adjustable finger I got at HF
Also get a piece of scrap copper pipe, cut it and open it up

 

[finn]

I think the copper spoon with a handle I have came from Harbor Freight..

I also made a backer from some 1 1/2 inch diameter thick wall copper pipe I found on the property. Just hammered it flat. That pipe is likely from a buried and long since abandoned water line left over from a powder mill that operated nearby in the early 1900s.

I also found a six inch square pure copper plate that someone probably liberated from one of the local smelters a hundred or hundred fifty years ago.. haven’t done anything with it yet, though. It came with the shop.

 

[kaymccampbell]

I found mine at a local scrapyard. I asked, they pointed me to a pile. I grabbed a couple pieces. They charged my card. Happy me.

 

[Wamsutta]

I'm told that copper bus bars from breaker boxes work good.

 

[mike93lx]

If you want to end the search with a couple clicks, this supplier has a bunch of sizes on sale

https://www.onlinemetals.com/en/buy/copper/0-125-x-1-5-copper-rectangle-bar-110-h02/pid/4265

 

[Gutman]

The previous owner of my house left behind various metal scraps, to include a small strip of 1" x 1/8" copper flat bar and some copper pipe pressed flat that worked initially when I was starting out.

However, I had some stainless projects to do, so I went the bougie way and bought a couple hunks of 2" x 1/4" copper flat bar from one of the online metal places. They actually had a sale on some drops they and they gave me 10% off and free shipping as a new customer. Got two 40" drops for under $40.

I cut one into smaller pieces to layout and clamp the joints of several frames made from ss angle and I was able to weld them with no distortion. I've also cut several pieces to serve as backing for joints in repairs with some bad fit-up or for welding up thinner metal where burn through was likely.

 

[toolenthusiast]

Yeah everyone’s constantly saying to hammer a piece of copper pipe flat but… I’m not a plumber? You’re much more likely to find me at the metal supply house. I bought a piece of copper square bar.

 

[Kscardsfan]

Find your local meth head.

 

[JradM]

You can buy copper bars, strips, sheets and other shapes on Amazon. They're not all that expensive - though certainly more than a piece of pipe from your local hardware store. Still cheaper than most genuine pre-manufactured welding backers.

Also, you can use aluminum as a backer too.

 

[Kscardsfan]

You can buy copper bars, strips, sheets and other shapes on Amazon. They're not all that expensive - though certainly more than a piece of pipe from your local hardware store. Still cheaper than most genuine pre-manufactured welding backers.

Also, you can use aluminum as a backer too.

Aluminum won't burn through?

 

[JradM]

Aluminum won't burn through?

Depends on the thickness and heat! Copper is better though. Just thought that might help someone looking for an impromptu backer. I certainly have a lot more aluminum lying around my shop than copper.

 

[dr_clyde]

Just buy some copper bar from McMaster-carr. A 6" length of 3/8" x 1 is less than $25.

You'll be much happier than trying to salvage some copper pipe or some other junk.

Copper is infinitely better than aluminum, especially for MIG work. Aluminum can and will stick to a MIG weld and mess up the whole job. I have a large assortment of copper bars, spoons, rolled sections and all kinds of customized shapes. I use them every day at work to fit up sheet metal corners on stainless pans or to back small parts as a heat sink.

 

[dr_clyde]

I save pretty much every scrap of copper bar or plate I come across. I have amassed a reasonably nice collection over the years, split between my personal shop and my box here at work.

I usually just buy a 3 or 6 foot section of whatever profile I use most and whittle it down to make whatever shape I need. We occasionally cut 1/4" copper sheet on the laser at work and I snagged the skeleton to cut all the useable shapes out of and stashed them in my area. Far more valuable as tools than as scrap.

 

[Stuart in MN]

Yeah everyone’s constantly saying to hammer a piece of copper pipe flat but… I’m not a plumber? You’re much more likely to find me at the metal supply house. I bought a piece of copper square bar.

I thought everyone has at least a couple pieces of scrap copper pipe or a fitting or two, laying around in the basement or sitting on a shelf in the garage.

 

[finn]

Yeah everyone’s constantly saying to hammer a piece of copper pipe flat but… I’m not a plumber? You’re much more likely to find me at the metal supply house. I bought a piece of copper square bar.

Menards, for one, sells copper pipe in relatively short lengths, like six or ten inches. They call them repair sleeves, and they’re pretty inexpensive.

Beats a separate trip to the sketchy part of town to a metal shop., or the scrapyard, where you have pretty good odds of having to figure a tire repair or replacement into the bill.

 

[Firebrick43]

Talk to an electrician. Copper buss bars are by far the best for heavy welding.

Also graphite plates/blocks are awesome to use as well, maybe even better as they don’t pull heat away as copper can. Graphite rod makes filling worn drawbar holes easy.

My graphite blocks came from a friend of my dad’s who worked on railroad track maintenance. I think the rods came from McMaster carr but it’s been 20 years now?

 

[dr_clyde]

By current stash I keep at work.

 

[Crazyjake8493]

I save scraps of copper pipe and hammer them flat or into whatever shape I need. You can add a handle on it if you want, though I typically don't.