Prerequisites for building a Tiffany-style stained glass lampshade are glass-cutting experience and (minimally) an intermediate level skill at copper-foil stained glass technique. The builder should also have access to workshop equipped with a glass grinder and other stained-glass tools, listed below.
Using the pattern you purchased at the stained glass supplier and carbon paper, trace your pattern in pencil onto tagboard.
Carefully cut each piece of tagboard with scissors, and fit onto the purchased moulding to make sure the pieces fit together correctly. These will serve as your cutting patterns. Mark the individual pieces as to colour and placement.
Using your tagboard pattern pieces, trace with glass marker directly onto the glass. Position several patterns around the piece of glass to make optimum use space, wasting as little as possible.
Cut the glass, using a glass cutter and pliers.
Fit each piece of cut glass onto the mould. Determine if and where it needs to be ground, and grind it on the glass grinder, until it fits perfectly onto the mould. It's also advisable to smooth the edges evenly, so that the piece doesn't need shaving. Remember to allow 1/16-inch space between each piece for the foil/solder.
Once all glass pieces fit together on the mould , they must be individually wrapped along the edges with the appropriate width of copper foil (size as per pattern), and snugly and evenly pressed over the sides, with the handle end of the scissors. Each wrapped piece of glass can then be placed back onto the mould.
Once all wrapped pieces fit onto the mould, they can be soldered. Using a paintbrush, and working in small sections, paint flux onto the copper foil edges, and solder the areas fluxed, using a steady motion to keep the hot solder flowing. Repeat for all areas of the shade.
After allowing time to cool, carefully remove the shade from the mould, and repeat the soldering process on the inside of the shade. This is also the time to solder a fitting into the top opening of the shade, which will enable attachment to a lamp stand.
With a mildly soapy water, clean the entire shade, inside and out, making sure to remove all remaining flux at the edges of the soldered lines.
Add a patina to the soldered lines to give them an aged appearance. Use a paintbrush to coat these areas. Clean, and enjoy your lovely, handmade Tiffany-like lampshade.
All of the necessary items, including all tools and grinder, are available at most stained glass suppliers. The lamp mould (or moulding) will often come packaged with a pattern. Copper foil can be removed once, and re-placed before the adhesive no longer sticks. Before taking on a project of this level, it is best to learn and practice both glass cutting and copper foiling technique.
Take care to unplug/turn off the soldering iron when not in use to avoid getting burnt, or burning out the iron.