Glass Kilns for Fusing & Slumping: What to Buy

Glass Kilns for Fusing and Slumping: The Complete Buyer's Guide

Glass kilns look similar to ceramic kilns from the outside, but they're built differently — and using the wrong kiln for glass work can lead to cracked pieces, uneven fusing, or worse. If you're getting into glass fusing, slumping, casting, or kiln-forming, here's what you need to know before buying.

How Glass Kilns Differ from Ceramic Kilns

The key difference is where the elements are. Ceramic kilns heat from the sides, which works well for pottery. Glass kilns heat from the top (lid elements) — because glass work needs even, radiant heat across the flat surface of the glass sheet. Side-only heating in a shallow glass kiln creates hot spots and uneven results.

Glass kilns are also typically shallower and wider than ceramic kilns, with flat bottoms that can accommodate large glass sheets. Temperature ranges are lower — most glass work happens between 1100°F and 1500°F, well below ceramic temperatures.

Key Temperatures for Glass Work

• Slumping (~1250°F–1400°F): Glass softens enough to drop into a mold but doesn't fuse layers together. Used for bowls, platters, and formed shapes.
• Tack fusing (~1350°F–1450°F): Glass pieces bond but retain their individual texture and shape. Good for surface texture effects.
• Full fusing (~1450°F–1550°F): Glass layers fully melt together into a smooth, unified sheet. Used for most fused glass art.
• Casting (~1600°F–1700°F): Glass flows into molds for sculptural work. Requires kilns rated to higher temperatures.

Top Glass Kilns at ProKilnSupply

Olympic CHAMP XL — A popular 120V glass kiln that ships fast and handles fusing and slumping beautifully. Great entry point for glass artists.

Evenheat GTS 28 — 28"x28" interior, ideal for large format glass work. Top elements for even heat distribution, max temp 1800°F. Serious studio kiln.

Jen-Ken AFG ProFusion 26 — 26"x26" interior, built for production fusing and slumping. Comes with the Glass Master controller for programmable firing schedules.

Jen-Ken AF Ceram-a-Glass 2422 — The dual-purpose kiln: fire ceramics to cone 8 or glass up to 1700°F. Perfect if you work in both media.

What to Look for When Buying a Glass Kiln

Size your kiln to your largest project — most glass artists work up to the edge of their kiln's interior. Check that the kiln has lid elements (or at minimum, combined side and lid elements). Look for a programmable digital controller with slow, controlled cooling capability — glass needs to be annealed (cooled slowly) to prevent cracking.

Also consider whether you want to do ceramic work too. Dual-use kilns like the Ceram-a-Glass give you both options in one footprint.