Rectangle Dam Kiln Casting Mold

The Rectangle Dam Kiln Casting Mold from Creative Paradise casts a single solid glass rectangle in one firing. The dam walls contain a casting area of 6 inches by 2.75 inches and about 1 inch deep, while the mold body measures 7.25 inches by 3.75 inches with an 8 inch diagonal on the kiln shelf, making it a practical choice for casting tiles, narrow decorative bars, pendant blanks, or other flat forms that require a clean rectangular shape.

Like all ceramic casting molds, this dam mold is COE agnostic. Load the cavity with at least three layers of frit, sheet glass, billets, or stacked scrap and fuse to a solid rectangle. Creative Paradise suggests at least three layers of COE96 glass when following the provided firing schedule. The mold is reusable across many firings when primed and cared for properly.

What does the Rectangle Dam mold make?
It casts one solid glass rectangle, approximately 6 inches by 2.75 inches, in a single firing. The form works well for tiles, decorative bars, pendant blanks, and any project that calls for a flat, cast rectangular piece.

What COE glass can I use in this mold?
Any COE. Ceramic casting molds are COE agnostic, so the same mold works with COE96, COE90, or other fusible glass. Match your firing schedule to the glass you are using.

How much glass do I need?
Creative Paradise recommends at least three layers of glass. Layer count and glass thickness affect the finished piece, so weigh your glass and test a first run when the result matters.

How do I prep the mold before casting?
Coat the cavity with a kiln shelf primer such as a boron nitride spray (for example ZYP) or a kiln wash such as Hotline Primo Primer, and let it dry completely before adding glass. Re coat as needed between firings.

Specifications

• SKU: 9655
• Manufacturer: Creative Paradise (CPI.GM74)
• Makes: 1 glass rectangle
• Finished piece size: approximately 6 inches L x 2.75 inches W
• Mold size: 7.25 inches L x 3.75 inches W x 1.75 inches T
• Diagonal: 8 inches
• Suggested fill: at least 3 layers of glass
• Material: ceramic kiln casting mold, reusable
• Glass: any COE (COE agnostic)

Working Notes

These are guidelines, not guarantees. Every kiln fires a little differently, so test a small run first when the result matters and follow a casting schedule suited to your glass and kiln.

• Prime the cavity with a boron nitride mold primer such as ZYP Boron Nitride Mold Primer, or a kiln wash, and let it dry completely before adding glass so the glass does not stick.
• Fill with at least three layers of frit, sheet glass, billets, or stacked scrap. Layer count and glass type affect the finished thickness and surface, so test a first run before committing to a full batch.
• The mold is COE agnostic. Use a full fuse schedule matched to your glass, adjusting the final anneal soak for your COE.
• Let the kiln cool fully before removing the cast piece. Re coat the mold with primer as needed between firings.
• The Slide Hi Temp brand separator is not recommended with these molds.

Creative Paradise Suggested Firing Schedule

This is a suggested COE96 starting schedule, not a guarantee. Every kiln fires differently. Test a small run and adjust the schedule for your glass and kiln.

Full Fuse (COE96): for at least three layers of glass.

*Segment 3 is the anneal soak at 950 F for COE96. If using COE90, adjust this temperature to 900 F.

Helpful downloads: Thick Channel Pendants Tutorial (PDF) · Fill Weights for Casting Molds (PDF) · Casting Mold Tips (PDF)

Description updated: July 6, 2026

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