Help, My Copper Foil Has Peeled Off!

by Tania
(Maryland)

My foil peels off the edge of my suncatchers, in spots when I tin them. I usually wash my pieces after I solder one side to prevent oxidation if I can't get back to it within several days. Is this causing the problem with the adhesive? How can I prevent this problem and how can I fix my almost finished dragon with tinned foil that's not stuck to the glass in a spot on the edge of his wing?

My foil peels off the edge of my suncatchers, in spots when I tin them. I usually wash my pieces after I solder one side to prevent oxidation if I can't get back to it within several days. Is this causing the problem with the adhesive? How can I prevent this problem and how can I fix my almost finished dragon with tinned foil that's not stuck to the glass in a spot on the edge of his wing?

Thanks so much for you site and help.

Answer

Hi Tania,

Yes, washing bare foil will often cause it to come off, especially if you use hot water. A better way is to wipe the piece off and put it in a zip lock bag until you can get back to it. The foil won't oxidize
over night. I've left pieces for several weeks, with nothing more than a wipe off, and have had no
oxidation problems.

I imagine what happened to your dragon is that the foil got loosened when you washed it, then flux got under the foil during your next soldering session. Once flux gets under the foil, the foil will not stick, no matter what you do. Not burnishing the foil well enough when you're applying it is another way for flux can get under any loose areas.

There is no quick fix to repair the loose foil on your dragon. The best way would be to remove the piece of glass with the loose foil, pull off the foil, clean the glass and re-foil it. That's what I'd do. Removing the glass as I describe here is pretty easy and shouldn't take you very long to do.

Believe me, I've tried every quick fix I could think of, and none of them work well, or they take more time than fixing it properly in the first place.

Here are my experiences with quick fixes:

One time consuming quick fix is to peel off just the area of foil that is loose. You need to cut the foil on either side of it, with an exacto knife, so you don't have ragged edges. Clean the bare glass to get rid of any adhesive and flux, being careful not to damage the remaining foil. Cut a new piece of foil just long enough to fit precisely between the edges of the gap. Put the foil on the glass and burnish it well. Once you start to solder, the new piece of foil usually ends up on the tip of you soldering iron. If it doesn't come off, the adhesive backing oozes out at either edge and you have black sticky stuff to try to clean off.

Another quick fix is to put some glue under the foil and try to get it to stick to the glass. You can't start soldering until the glue dries. When you do solder over it, the heat of the iron usually causes the glue to soften and ooze out, which makes a mess, plus you're back to having loose foil.

So, back to option number 1. Take out the glass and re-foil it. It will look better and take less time in the long run.

Perhaps someone reading this knows of a quick fix that works. If so, please tell us by using the comments section below.






Thanks so much for you site and help.

Tania