Casting, Pot Melt, and Drop-Out Schedules

01 / More movement

In basic fusing, glass may bond and smooth. In slumping, it bends into a mold. In casting, pot melts, and drop-outs, the glass may flow, stretch, gather, fill, or hang in ways that create very different stress and heatwork questions.

That extra movement means setup matters as much as temperature. Mold material, dams, containment, kiln furniture, shelf protection, aperture size, glass volume, and support geometry all influence what the schedule can safely do.

Before firing, understand the physical path. Where will the glass start? Where is it supposed to go? What stops it? What supports it? What happens if it moves too far or not far enough?

Special-process schedules control a physical journey, not just a surface result.

02 / Casting logic

Casting usually involves thicker glass and a mold or containment system. The schedule has to heat the glass, let it flow or settle into the form, then anneal for the actual thickness and shape of the cast object.

Molds can absorb heat, slow the firing response, and affect how glass fills details. Glass volume, billet or cullet arrangement, mold material, vents, dams, and reservoir design can all change the result.

The annealing phase is especially important because cast work often has more mass than ordinary sheet projects. A casting may look solid and successful while still needing a very careful stress-relief plan.

In casting, the schedule has to serve both the mold and the mass of glass.

03 / Pot melt and drop-out logic

Pot melts and drop-outs rely heavily on gravity. In a pot melt, heated glass flows from a container or opening and gathers below. In a drop-out, a glass sheet softens and sags through an aperture to create a vessel or form.

Because the glass is moving under gravity, timing and observation can matter. Too little heatwork and the movement may be incomplete. Too much and the glass may stretch, thin, distort, hit a shelf, or move beyond the intended form.

These firings also require safe physical setup. Kiln furniture, shelf protection, containment, aperture height, and clearance must be planned before the schedule starts. The written schedule cannot compensate for an unsafe or poorly supported setup.

Gravity can make elegant forms, but it can also quickly turn extra heatwork into distortion.

04 / Process-specific caution

Casting, pot melts, and drop-outs are not ideal places to invent a schedule from a basic full-fuse or slump recipe. The process-specific details matter too much: glass system, volume, mold, setup, desired movement, and annealing thickness.

Start with manufacturer guidance, teacher instructions, or tested studio notes for the specific process. Then adapt slowly and document what changes. Treat the first firing as information, not proof that the process is universally solved.

If you use Kiln Schedule Designer for planning, use it as a way to think clearly about segments, holds, and annealing — not as a substitute for process-specific safety knowledge and tested schedules.

Special processes deserve special schedules, not recycled basics.