Firing

Firing Schedule Generator

Generate a complete multi-segment kiln firing schedule for bisque or glaze firing.

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What Is a Kiln Firing Schedule?

A firing schedule is a sequence of temperature ramp rates and hold times that controls how a kiln heats and cools. Each phase addresses a specific physical or chemical event in the clay and glaze: moisture release, organic burnout, quartz inversion, and final vitrification.

Critical Temperature Zones

Zone Range What Happens
Candling20–120°CMechanical and steam water evaporates
Burnout120–600°CChemical water releases; organics burn off
Quartz Inversion~573°CSilica changes crystal structure — rapid expansion/contraction
Approach900°C → peakGlaze melts and fluxes activate
SoakAt peakTemperature equalizes throughout the load

Bisque vs. Glaze Firing

Bisque firings require slower early rates to fully burn off organics without blowing out pieces. Glaze firings can be faster through early stages but need careful control through the quartz inversion zone and a controlled approach to peak temperature to allow the glaze surface to develop correctly.

Frequently Asked Questions

Why are there multiple segments in a firing schedule? expand_more
Different temperature ranges require different ramp speeds. Slow through steam and quartz inversion zones prevents cracking. Faster through intermediate ranges saves time. Slow final approach to peak ensures even heat work.
What is a soak (hold) at peak temperature? expand_more
A soak holds the kiln at peak temperature for 15–30 minutes to equalize temperature across the kiln load and allow glazes to fully mature. It is equivalent to adding heat work without raising the peak temperature.