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Firing Schedules: Guidelines for FUSING and SLUMPING 12-inch projects of various thicknesses up to 3/8-inch thick.
THICK Firing Schedules: Guidelines for firing THICK projects ranging from 1/2-inch to 2-inches thick
Technical Data: Strain Point, Annealing Point, Softening Point, Product Density
Firing Stages: Forming stages, definitions, and temperatures for firing System 96 products.
Bubble Squeeze: Adding a stage during firing to reduce or eliminate bubbles
Annealing: Simple advice for thorough annealing
4-Segment Firing: How to easily adapt our 6-segment programs to 4-segment controllers



The Schedules below are guidelines only, not strict rules. Times and temperatures may be adjusted based on the nature of your project.

Fusing
For FUSING and annealing 12-inch projects of various thicknesses.
Segment Thickness Rate Temp Hold
(inches) (°F per Hour) °F (minutes)
1. Heating I: 1/8 500 1000 0
(Heat from room temp to softening temp) 1/4 400
3/8 300
here is data
2. Heating II: 1/8 1000 1465 Desired

Effect

(Heat to fusing temp) 1/4
3/8
here is data
3. Cool to Anneal: 1/8 As fast as possible 1000 5
(Cool down to anneal zone & equalize kiln temp) 1/4 8
3/8 10
here is data
4. Anneal I: 1/8 600 950 10
(Ease down to anneal point & hold) 1/4 300 20
3/8 200 40
here is data
5. Anneal II: 1/8 300 800 0
(Cool to below strain point) 1/4 200
3/8 100
here is data
6. Cool Down: 1/8 800 120 0
(To room temperature) 1/4 400
3/8 300
Fusing Cycle Graphs:
1/8-inch 1/4-inch 3/8-inch Overlay



Slumping
For SLUMPING and annealing 12-inch projects, of various thicknesses.
Segment Thickness Rate Temp Hold
(inches) (°F per Hour) °F (minutes)
1. Heating I: 1/8 500 1000 0
(Heat from room temp to softening temp) 1/4 400
3/8 300
here is data
2. Heating II: 1/8 1200 1225 Desired

Effect

(Heat to fusing temp) 1/4
3/8
here is data
3. Cool to Anneal: 1/8 As fast as possible 1000 5
(Cool down to anneal zone & equalize kiln temp) 1/4 8
3/8 10
here is data
4. Anneal I: 1/8 600 950 10
(Ease down to anneal point & hold) 1/4 300 20
3/8 200 40
here is data
5. Anneal II: 1/8 300 800 0
(Cool to below strain point) 1/4 200
3/8 150
here is data
6. Cool Down: 1/8 800 120 0
(To room temperature) 1/4 400
3/8 300
* As Fast As Possible.
Slumping Cycle Graphs:
1/8-inch 1/4-inch 3/8-inch Overlay


4-Segment Firing
Eliminate Segments 2 and 6 by simply continuing your Segment 1 rate to fusing or slumping temperature. Stop firing after Segment 5, allowing your kiln to cool at its natural rate (door closed, power off) to room temperature.


Annealing Simple Advice for Thorough Annealing
To assure a good anneal, we advise holding at 950°F (510C) for the recommended time, then slowly ramping down (around 150° per hour) to 800°F (427C) Holding time and ramp speed depend on how big and thick your project is. Refer to Firing Schedules for guidelines.
Bubble Squeeze Guidelines for Controlling Bubbles
If you’re seeking to reduce or eliminate bubbles, try slowing the rate of heating in Segment #2 (Heating II). Inserting a half-hour soak at around 1220° F (660°C) may also help, allowing added time for air to escape from between glass pieces before the edges seal and trap it in the form of bubbles. For large projects, experiment with a “ramp squeeze,” a very slow ramp to tack temperatures, say 60° per hour from 1100-1300°F (590-704°C). If your project has a clear base, consider using our “Double Thick” clear instead of two layers of regular clear. You can’t trap air where there isn’t a space.
Technical Data
Strain Point* Anneal Point* Softening Point
Fahreneheit:
890 (+/- 10) 955 (+/- 10) 1255(+/- 10)
Celsius:
476 (+/- 6) 513 (+/- 6) 680 (+/- 6)
*At the At the Anneal Point of a glass, internal stresses are largely relieved in a matter of minutes. At the Strain Point, internal stresses are substantially relieved in a matter of hours.
Product Density
Grams/ Cubic Centimeter (g/cm3)
100SFS
2.5095
Studio Nuggets
2.69
200SF
2.343

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