Typically, I fire polish and slump in the same firing, as it’s best to try and fire recycled glass as few times as possible to reduce the possibility of devit. However, if you do want to fire polish without changing the shape of your glass piece, the following schedule is a good place to start.
Fire Polish Firing Schedule Bottle and Window (Float) Glass (1/4″ thick glass or less)
Fire Polish Firing Schedule Bottle and Window (Float) Glass (1/4″ thick glass or less)
| Ramp Temp | To | Hold For |
| 240/hr | 500 | 10 min |
| 240/hr | 1275 | 5 min |
| 0/hr (as fast as possible) | 1060 | 20 min |
| 150/hr | 850 | 0 |
| 300/hr | 650 | off |
TEST YOUR KILN!! I can’t emphasize this enough. All kilns vary. Start with my schedule, if your test glass warps out of shape, go down 20 degrees and try again. If your test glass doesn’t fire polish, go up 20 degrees and try again. Firing a full batch of glass art with an untested firing schedule is madness. Don’t do it! (and if you do, do not write to me and complain about it)
This schedule would be good for:
- Drinking glasses made from bottles
- Tumbled glass beads that need to be shiny
- Slumped works with coldworked edges