Tuesday, January 27, 2009

Tuesday Tips - Foiled Again

Louis Comfort Tiffany (1848-1933) started it all by making lovely lampshades with many intricately cut pieces of glass to create florals that drip with color, shine and glisten when lit.

Stained glass windows are made using lead channels soldered together to enclose the stained glass. But that method is heavy and not flexible enough to make the domed and rounded shapes Tiffany wanted for his lampshades, using the newly available translucent 'milky' opalescent glass. It did not allow him the lighter weight and extremely fine detail that became his signature style.

Tiffany developed the copper foil method of wrapping the glass.

He decided to cut thin foil sheets into strips and applied an adhesive, to wrap the edges of the glass in the copper metal foil to solder them together with a lightweight and flexible strip of metal. Imagine cutting all those copper sheet strips individually by hand!

His first lampshades made using this technique were made around 1895. He arranged the bits and pieces of discarded or broken glass from production of stained glass windows to make the lampshades, collaborating with Thomas Edison to create electric lamps with exquisite stained glass shades.

Sometimes we forget that electric lighting doesn't go back all that far in history!

You can wrap almost anything in copper foil tape - glass, stones, marbles. Metal, ceramics - anything that can withstand the acidity of the flux and take the high temperatures of the soldering iron.

Hints and tips for protecting and using
copper foil sheet and tape:

1. Use the width of foil you need for your project. A too-narrow width won't provide enough grabbing space to hold the pieces together, and a too-wide foil will cover too much of your glass or ceramic cabochon.

2. Be sure whatever you are wrapping with the foil is really clean and dry. Use alcohol to clean glass, it removes oil from your cutting tool or fingers and evaporates quickly leaving no trace of residue behind. If you've used the grinder on your glass to shape it, it's worth taking the time to scrub the edges briskly in a small bowl of soapy water with a discarded soft bristle toothbrush, to make sure all the grinder residue is gone. This helps the adhesive adhere tightly.

3. Protect your copper foil from oxidation before you use it. If the copper foil roll or sheet sits out in the air, it will oxidize and slightly darken. Oxidized metal is much harder to flux and solder. If your foil has turned dark, you may be able to cut away the part of the roll that's exposed and get back to clear copper. If your copper sheet has turned dark, you can scrub it with a metal brillo scrubby pad to remove the oxidation. Keep your foil rolls and sheet stored in plastic bags tightly rolled to protect them.

4. Avoid the springy loose strands of foil going everywhere, this promotes oxidation over large areas of foil. I use a twist-tie around the roll from the middle to the outside edge and keep the roll tightly packed. This keeps the air away from the inner layers of your foil and keeps it from unrolling, twisting and getting creased and bent before you can use it.

5. Copper foil comes with various backings available, in regular copper, silvertoned and black. There's also a new foil available in brass sheets. Choose the foil that works best for your project - if you are doing a black patina on your piece and the glass is transparent, use black-backed foil so it harmonizes when your project is finished.

6. The copper foil has an adhesive on the back that works with the heat of your soldering iron to adhere it to the glass. After you remove the protective film from the copper foil, as much as possible keep the sticky side of the foil away from fibers, lint and your fingers to avoid reducing its sticky nature, and burnish the foil down tightly before soldering. If it doesn't seem securely stuck down before you solder, take the time to remove it, get a new strip of foil and re-apply. It's actually faster than fussing around with an insecurely stuck foil strip that's become iccky with flux and hot from soldering.

7. If you do have to remove the foil and try again to reapply after you've soldered it, soak your glass in soapy water and scrub well with a brass brush to remove all the old sticky residue before you reapply the tape. The water makes the foil release better, and the brass brush cleans all the remainder of the old tape before you try again on a clean glass surface.

Hope these copper foil tips and hints are useful! They've been learned in the school of hard knocks and experience and shared here so you don't have to learn them the same way. Let me know if you are curious about more stained glass - soldering - copper foil tips!


SummersStudio said...

Wonderful post Lynn. Very clear. I'm inspired to get my mum to show me the ropes. She's done leadlight for years. Thanks, LeAnn

LLYYNN said...

Thanks, LeAnn. You can (if you want to try it) wrap ceramic pieces in copper foil and solder them, it works well! It's also interesting to combine glass, metal and ceramic in one mixed-media piece. Just be patient when you're first learning and watch that iron, it is HOT-HOT!

If you do try it out, I'd love to see....

EmandaJ said...

Hello Lynn,

Thanks for the clear directions and for pointing out what has caused me the most problems: trying to work on a piece that is not properly cleaned in the first place. You should have heard my hand slap my forehead -- Duh!


LLYYNN said...

Interesting, Emanda, because my 'light bulb moment' was about the oxidization and failure to burnish enough to stick down the copper foil tape.

But yes, little fingerprint oils will interfere with the sticking down, which is the first step to a do-over, at least for me!

Glad this helped!