A search on the internet under "Slumping"
will provide you with a ton of molds for this procedure, but not much information.
What is it and how is it done?
This is a term used for glass that has been heated enough that it actually bends and sags into a mold.
Generally this movement occurs around 1200 degrees Fahrenheit, depending on your individual kiln.
This is typically done in a prepared mold.
When done over objects, it is refer to as draping.
The glass begins to bend and sag at about 1200 to 1300 degrees Fahrenheit.
This procedure can be done with one piece of glass, but the norm is to first fuse two or more pieces to a full fuse.
Once these pieces of glass have fused together, they are shaped to the size of the prepared mold or surface you want to use.
Then they are positioned on top of this mold or surface, and placed back into the kiln and heated up to where they slump into the prepared shape.
There are a ton of molds that can be used for this process.
They come in just about every size and shape you can imagine, and for just about any holiday you want to celebrate.
Before purchasing any molds, be sure that they are small enough to fit inside your kiln.
Begin by deciding what you want to design.
Pick your mold, and cut your glass pieces.
You can use glass that is smaller than your mold, but keep in mind that the object will be about the size of the glass you cut.
Try to make your piece about the size of the mold.
If you make it larger than your mold, it will not only bend into the mold, but could bend on the outside of your mold, trapping the mold in the glass.
If you are not sure what size your glass should be, please read the section on
mold glass size
You don’t have to do a full fuse at this point, but most people do, because you have more control over how your glass will come out after firing.
If you have several pieces sitting on top of a single piece and it begins to move, your pieces will also move.
Also the finished surface will not be flat, because your pieces will not melt into each other, as they do with a full fuse.
So, fully fuse your pieces together.
Once they have been fused, allow them to anneal and cool.
If your piece is larger than the mold you want to fuse into, you can either use a grinder to remove the excess glass, or a glass saw.
It would be difficult to cut with a glass cutter, because of the thickness of the glass.
Be sure to prepare your mold before fusing.
The mold should be coated with several layers of kiln wash.
Allow the wash to dry before firing.
Place your fused piece of prepared glass on the mold and put it back inside the kiln.
You will only want to heat the kiln up to around 1200 to 1300 degrees for this firing.
Keep an eye on your piece, either through the peep hole, or by quickly lifting the lid and looking at the piece.
If you are going to look inside the kiln, remember to wear your safety glasses.
Once your piece has slumped and you like the appearance, start your annealing process and cool your piece.
Return from this page to one of the following pages:
Fusing and Slumping
Slumping to Glass Fusing Made Easy