The Tiffany style stained glass lamp shade, panel, window etc. is very much like a puzzle.
First, the puzzle must be designed. The design may begin as a drawing, a painting, a photograph or any other kind of graphic artwork. Once this basic design is selected it must then be transformed into a stained glass friendly design. Stained glass panels, shades, doors, windows, etc. are subject to stress which can easily break or fracture the glass. Care must be taken to design the individual pieces and how they relate to each other structurally in such a way that they will add strength. Of course this all has to be done within the context of a beautiful design. A simple comparison is a wall of bricks. To create a strong wall you would not simply stack the bricks in a line on top of each other but you would place them in such a way to interlock and create a strong bond. Stained glass structural design is similar in principle. A further complication is that it is always necessary to maintain the beauty and integrity of the original subject which is the object of the design.
Second, upon completion of the stained glass friendly design which is structurally sound and aesthetically pleasing, it is necessary to create templates for each and every piece of glass that is to be in the design. This is typically done by tracing the outline of each piece of glass in the design onto a heavy craft type paper. Afterwards, the craft paper is cut into individual pieces which represent the individual pieces of glass.
Third, each craft paper template is laid down upon a corresponding sheet of glass and cut out by hand with a glass cutter tool. The rough edges of the glass are smoothed by special grozing pliers or a glass grinder. All the pieces are cut out in this manner then laid out upon a copy of the original design to assure that everything fits properly.
Fourth, each piece of glass is individually wrapped around the edge in (usually) copper foil or a zinc frame then placed back onto a copy of the original design to assure proper fitting. Metal pins, straight edges and wood frames are used to hold the entire project in place in preparation for the soldering .
Fifth, all copper foil and zinc edges of all the glass pieces are painted with a
Finally, detailed finish
There are many subtleties and variations in each of the steps above. But there are no short cuts or machinery other than simple hand tools used in authentic Tiffany style stained glass.
– Jim Hoyle