Placing Copper behind holes in sheet metal to fill them, or behind 2 pieces of sheet metal that you are Butt Welding, or maybe to fill a slightly larger gap makes it a lot easier to obtain a better weld and helps avoid burn through. I already bought a Spoon at Harbor Freight, (see photo), for a good price that works well in some areas but leaves you only one hand to weld with. You can buy 2" x 4" Flat Copper Plates with Magnets that work well and leaves both hands free but just one costs around$23.00.
I made my own, maybe someone has already shared this in the past, from a 3" x 12" x 1/8" Solid Copper Plate and some Rare Earth Magnets that are very powerful.
I got the Copper remnant from eBay for $18.00 and the Magnets (10) from Harbor Freight for $2.99 plus Tax; add a few more dollars for Epoxy if you don't have any, I already had it on-hand.
As you can see in the photos, I cut the Plate into eight 1-1/2" x 3" pieces and inserted 2 magnets per Plate; this allows for multiple placement when welding a larger panel like a floor board; the Magnets are 5/16" in diameter. The best part is that it cost about 1/10th for all eight as compared to a single 2 x 4".
Hope this may be of help to someone else.
Ray
