Heart Knobs Casting Mold

The Heart Knobs Casting Mold from Creative Paradise casts two heart shaped glass knobs in a single firing, with each finished knob measuring 2.25 inches by 2 inches. The mold footprint is 5.5 inches by 3 inches, making it a compact tool for producing a matching pair of decorative drawer or cabinet pulls in one kiln run.

Like all ceramic casting molds, this one is COE agnostic. Fill the cavities with frit, billets, or stacked sheet scrap and fuse to the heart shape. Note that Fiberfrax kiln fiber paper is required for this project. As a kiln casting mold it is reusable across many firings when prepped and cared for properly. Hardware for mounting the finished knobs is sold separately.

What does the Heart Knobs mold make?
It casts two heart shaped glass knobs, each 2.25 inches by 2 inches, in one firing. They are suited to drawer pulls, cabinet hardware, and decorative accents around the home.

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.

What is Fiberfrax and why is it required?
Fiberfrax is a high temperature ceramic fiber paper used as a kiln shelf liner. Creative Paradise specifies it as required for this knob casting project to support the mold and protect the kiln shelf during firing.

How do I prep the mold before casting?
Coat the cavities 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. Place Fiberfrax on your kiln shelf before setting the mold in position.

Specifications

• SKU: 12988
• Manufacturer: Creative Paradise (CPI.LF54)
• Makes: 2 heart knobs
• Finished piece size: 2.25 inches L x 2 inches W each
• Mold size: 5.5 inches L x 3 inches W
• Suggested fill weight: about 29 grams per cavity
• Material: ceramic kiln casting mold, reusable
• Glass: any COE (COE agnostic)
• Required accessory: Fiberfrax kiln fiber paper

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 cavities 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.
• Fiberfrax kiln fiber paper is required for this project. Place it on your kiln shelf before setting the mold in position and firing.
• Fill the cavities with frit, small billets, or stacked sheet scrap. For a tack fired surface, fill uniformly to about a quarter inch with powder and fine frit.
• Hardware for mounting the finished knobs is sold separately. The cast knobs will need mounting hardware to install them as drawer or cabinet pulls.
• 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 knobs. 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):

Tack Fire (COE96): for a tack fired surface, fill uniformly to about a quarter inch with powder and fine frit.

*Segment 4 is the anneal soak at 950 F for COE96. If using COE90, adjust this temperature to 900 F.

Helpful downloads: Knobs and Pulls Tutorial (PDF) · Fill Weights for Casting Molds (PDF) · Casting Mold Tips (PDF)

Description updated: July 6, 2026

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