Allen
I have used copper backing bars for years, and not always without problems caused by melting the copper into the steel. I general, copper backing is very good. I have never seen a "Magnetic" copper welding backer.
I saw these just recently too, and was wondering the same thing. It sure looks like a neat idea.
A pair of C clamp vice grips and a small plate of copper has usually worked good for me on a lot of insane gaps. I'd only use it as a structural cheat though, and only if you're going to gouge/grind out the bottom side! :)
Nice looking. How much does it cost?
The item pictured is $36.
I have only seen them in pictures, but keep in mind that high temperatures kill magnets, so don't let them get real hot.
I stay away from copper backing if there is any chance the arc could impinge upon it. Copper doesn't get along with most other metals. It seems to make nearly everything crack.
Best regards - Al
When used properly these should never get to the melting point of the copper. I do agree that copper mixing in with the molten steel can cause problems.
Ive never used copper. Have yall ever used brass backing plates?
Copper has a higher melting temperature and conducts the heat away faster. It works better than brass. In high quality work where contamination from the copper is an issue they nickel plate the copper.
agreed. we had some transverse cracking in some sub arc welds and it took a very seasoned veteran in our shop to realize that it was the contact tip coming in contact with the puddle that caused them. i was very impressed with his diagnosis as we had a lot of welding experts that couldn't figure it out and the man with the hands on experience nailed it right away. our company and the welding machine company spent some serious money to find out why our brand new state of the art welder was leaving these little transverse cracks in our weld; copper impregnation.
darren
never used copper but I have used brass and it work pretty good but dont put it in a hole to build up around it. Like any metal it expands, one good thing it don't stick and you can let the arc get pretty close. It only scars the brass but don't impregnate the steel.
they make some fiberglass/fiber material backing straps for filling gaps. Got it from a vendor at a safety day cookout. Haven't tried it but the F&M Mafco vendor said it works very well. One side is sticky to keep it in place.
find some "sparkys" on your next job and ask them about old bus bars. They come in various sizes and lengths and work very well for backers.
take your time fitting and cutting body panels try to get it with zero gaps if you want any tips on welding in panel i've done quite a few quarter panels and rockers ,floors etc.
Feel free to pm me