I need your feedback == Copper Welding Backers

Date 08-06-2008 01:14

I was looking through the Eastwood catalog and saw that they have for sale 4 and 8 inch "Magnetic" Copper welding backers. If these things are magnetic will it effect the mig welding?? Has anyone out there used these? If so would you buy them again? I am building a steel 32 Ford pickup. I am a novice welder and will be doing steel body work. I need all the help I can get. If they work I'll try them out. Thanks for your feed back
Allen
Ocala, Fl.

By FixaLinc (****)

Date 11-14-2008 20:28

I've just used scrap copper sheet in vise grips held behind and sometimes takes a helper to hold it. Guess you could glue magnet strips or the self stick stuff on copper sheet laying around to find out. Have to be good magnets like newer rare earth though as welding heat and current will change the molecules in older magnet metals making it useless.

By rlitman (***)

Date 11-14-2008 21:00

I've found that the rare earth magnets are more heat sensitive than the older stuff, even if they're much stronger.

By jstasney (*)

Date 07-03-2009 15:01

You can use brass for a backer, copper welds to steel.
Yes, a magnet will jack with DC MIG . You can use a very close arc with it in short arc with gas.
I wouldn't think flux core would work very well. Never tried though.
Look at Eastwood again, they make a tool for forming flush welded lap joints.
You cut a section out, form the lap joint bead around the perimeter of the cut, lay the new cut piece in the formed area and stitch weld it in.
Works great.