2nd Side Soldering Problems
Love the site, so helpfull. Thanks.
I have a problem. I make pictures around 5'x3'. When I turn them over, the copper is either black or green, which I clean off with a scouring pad. It pulls off the copper foil how ever I try.
Is there something out there that I can brush on to clean the copper? It takes me about 2 weeks to finish the first side, so you can see the gunk that grows on the 2nd side.
First of all, lets talk about the cause of the "gunk". In my opinion, you are using too much flux. It runs over the edges of the panel, puddles underneath and causes oxidation on the foil. The foil is then sits in the flux for 2 weeks or so. The solution is to use less flux. Use a Q-tip, to apply it, rather than a brush. Only flux what you will solder during that particular session. You don't have to use a lot of flux, just enough to moisten the foil.
When you are finished soldering each day, wipe off the panel with a paper towel, making sure it is free of flux. A better solution yet would be to spray on a flux remover, wipe it off and dry the panel. CJ's, Classic and Solder-Magic all make flux removers. Removing the flux every day will also keep the seams, that you already soldered, shiny and bright. That will save you time when you do the final clean up of the finished panel.
Yes, using a scouring pad will cause damage to the foil. Try rubbing over the foil with a paper towel dipped in alcohol. Rub up and down the seams rather than cross wise. Rubbing across will tear the foil off in no time at all. If the alcohol doesn't work, use Bronzo which is a bronze wool carried by some stained glass retailers. It doesn't leave residue like steel wool does. If you can't get any Bronzo, use very fine steel wool. Whatever you use, again rub up and down the seams, not cross wise.
Another thing you can try is the flux remover. Spray it on, let it sit for a few minutes, then wipe it off. Then go over the foil with a wet paper towel to get rid of the flux remover before you flux and solder that side. I'm not sure if the flux remover will work, but it's worth a try.
Hopefully, eliminating the cause will prevent the problem or at least minimize it so you won't have so much to clean up.
Let us know what works best for you.
PS... If anyone reading this has a tried and true way to solve John's problem, please tell us what you do. I'm sure John would appreciate any help you can give him.