What is slumping? | Bullseye

Glass for Art and Architecture

What is slumping?

Slumping, or firing glass in a kiln in order for it to sink into a molded form

Slumping is a kilnforming process that uses heat and gravity to transform sheet glass into the shape of a mold. One can to create an almost endless variety of forms when slumping glass.

When the glass is heated in a kiln and enters a liquid state, the force of gravity pulls it to the floor. In glass slumping, this “floor” is some type of mold.

After the heated glass has flowed into the mold and assumed its shape, it is cooled back down to room temperature with an appropriate annealing phase. By the time the glass is fully returned to room temperature the liquid glass will be crystallized into the rigid form of glass with which we are most familiar. Its new permanent shape will be that of the mold.

Slumping is a process that is commonly used to make food-bearing objects such as bowls and platters, but with some creativity one can create all kinds of interesting variations.

Related Questions

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Helpful Resources

Video lesson: Slumping Basics
Tips for Using Bullseye Slumping Molds
Quick Tip: Suggested Slumping Schedules
Multitasking Molds
Mold Tips: Big Bowl
Mold Tips: Cone Bowl
Mold Tips: Deep Form
Browse slumping molds at the Bullseye Online Store


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