Annealing Cycles for torch-made glass

I’ve been asked many times to publish the annealing cycles I use in my controllers and kilns, here they are:

Ambient = Room Temperature
Garage Temperature – Hot Kiln Temperature (soft glass between 900 and 950, boro between 950 and 1000 degrees)

1 – Batch Cycle (Soft Glass only)

from ambient, ramp to 960 over 3 hours (5.33 degrees per minute)
HOLD 960 for 1 hour, 30 minutes
Ramp DOWN to 850 over 2 hours (0.83 degrees per minute)
HOLD 850 for 10 minutes (the pause that refreshes)
Ramp DOWN to ambient over 1 hour (or shut off the kiln)

2 – Daily Annealing Cycle, soft glass (assumes kiln is at garaging temperature)

from garage temperature, ramp to 960 over 10 minutes
HOLD 960 for 1 hour, 30 minutes
Ramp DOWN to 850 over 2 hours (0.83 degrees per minute)
HOLD 850 for 10 minutes (the pause that refreshes)
Ramp DOWN to ambient over 1 hour (or shut off the kiln)

3 – Daily Annealing Cycle, Boro, Color Strike (assumes garaging temperature)

from garage temperature, ramp to 1000 over 10 minutes
HOLD 1000 for 30 minutes (this allows the last piece to soak at least 30 minutes)
Ramp UP to 1225 over 10 minutes (22.5 degrees per minute)
HOLD 1225 for 30 minutes (longer the hold, the more the crystals grow)
Ramp DOWN to 1050 over 30 minutes (5.83 degrees per minute)
HOLD 1050 for 30 minutes (this is the actual annealing part of the cycle)
Ramp DOWN to 950 over 30 minutes (3.33 degrees per minute)
HOLD 950 for 10 minutes (the pause that refreshes)
Ramp DOWN to ambient over 1 hour (or shut off the kiln)

4 – Daily Annealing Cycle, Boro, no strike (assumes garaging temperature)

from garage temperature, ramp to 1000 over 10 minutes
HOLD 1000 for 30 minutes (this allows the last piece to soak at least 30 minutes)
Ramp UP to 1050 over 10 minutes (5 degrees per minute)
HOLD 1050 for 1 hour, 30 minutes
Ramp DOWN to 950 over 30 minutes (3.33 degrees per minute)
HOLD 950 for 10 minutes (the pause that refreshes)
Ramp DOWN to ambient over 1 hour (or shut off the kiln)

These are fairly conservative cycles, but I will note that in using these, I have not broken a single bead, sculpture, or pendant.

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