Coldwork and Slump

With the bowl “blank” fired, the last steps are to clean it up and slump it.  At this stage you have several options (which can be used in combination):

  • Trim the edges with the tile saw to clean and straighten them.
  • Cut or grind the corners to round them.
  • Sandblast the surfaces to “scrub” them clean.
  • Fire polish the piece to bring the front to a high gloss.
  • Smooth the front and/or back with either a flat lapidary grinder or diamond hand pads (as shown here:

Coldworking fused glass with diamond hand pads.

Place the piece on your chosen slumping mold, as shown in here:

Ready to slump our fused glass bowl.

Slump with the following schedule:

12001000FIf you have a shallow kiln, where the heating elements are less than 6 inches from the top of the glass, consider slowing this segment down to avoid thermal shock.
21001200FA slow, steady ramp to 1200 will allow for even heating and, consequently, even slumping.
3FULL960F2 hrsAnneal soak
4100700FAnneal cooling
5300100FFinal cooling

That’s it – your bowl is complete!  Don’t be surprised if you find yourself looking at your scrap fusible glass in a whole new way!