Jan
19
How to make a mold from a glass vase/hurricane lamp for copper foil stained glass lampshade?
ByI see really cool shapes of glass bowls and vases that would make for really cool stained glass lampshades. I don’t want to just mosaic glass pieces onto them, I want to make copper foil method lampshades. I can’t use the glass bowls/vases themselves as molds obviously because the glass would crack when I soldered the pieces together. Any ideas on materials to use and how to go about making a mold? Think it can be done?
3 Comments
January 19th, 2010 at 6:08 am
coat the outside of the object you are molding with some sort of grease or oil (just enough to prevent sticking). Then cast the object in plaster (the quick dry or medium dry at room temperature works best). You may want to cast one side at a time so you can easily get the plaster mold off without breaking the glass. Then once you cast each side put the two sides together, seal them using more plaster, now you have a mold.
January 19th, 2010 at 6:32 am
try cutting a shape out of parchment paper that is like our object. copper foil onto the parchment. it will burn when you solder the pieces but with a little ventilation, you should be ok.
January 19th, 2010 at 7:11 am
Lamps and lampshades in stained glass are traditionally done on styrofoam forms as you can find on sites like Delphi stained glass.
To duplicate a form, build a blank out of slabs of styrofoam from hobby stores or styrene beadboard used in packing glued together with yellow or white wood glue. Mount it on a plywood disk with a rod through it then spin it with a drill press or hand drill and form it with a rasp using a cardboard or metal profile fitted to the glass (like this http://users.ticnet.com/mikefirth/castgobl.htm#ALBLOMOLD )
Using foam will allow you to put in pins, etc, to hold while you solder. You will only solder joints on the form, lifting off to solder the length of the foil and the back.
You will build no more than half of the foil work at a time, perhaps only a third. Use the finished pieces to set size of next, but don’t solder them together.
When done with all the pieces, position them together and support with props and string to tack solder the final seams and then do the seams.