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ZYP Tips

ZYP Tips for Ceramic Casting Molds

Download the ZYP Tips for Ceramic Casting Molds PDF

ZYP Boron Nitride Aerosol Lubricoat (8714) is a separator that can be applied to ceramic casting molds as a release between the mold and glass. It can be very effective and easy to use—win win!

Important Product Information

Once you apply ZYP to a ceramic mold, it permanently affects the surface and, from then on, other separators such as Bullseye Shelf Primer cannot be applied. So, that mold becomes designated for ZYP only!

ZYP has amazing properties as a separator. Although it can be used with other types of molds, this article is about its use with ceramic casting molds.

We don’t recommend use of this product with ceramic slumping molds. The particles of ZYP are spherical, have low resistance, and will only succeed in turning a steep-sided slumping attempt into a puddle of glass at the bottom of the mold.

General Directions for Using ZYP on a Ceramic Casting Mold

First Firing

  • Start with a dry, clean mold, free of any primer.
  • Spray two coats of ZYP following the notes below, allowing about 5 minutes between coats.
  • Allow it to dry for 15–20 minutes.
  • Load glass into the mold gently so as not to disturb the thin, delicate coating.If the separator is scraped away, your piece may stick to the mold. Smaller grain sizes of frit are commonly used in ceramic casting molds and are relatively easy to load. Larger grain sizes of frit, bits of sheet glass, and cut billets are more prone to result in a texture or mark in the finished casting. Then fire your project.
  • After firing, remove your casting, then buff/remove used ZYP primer from the mold with a dry, stiff-bristle nylon brush. The surface will develop a slight sheen and some of the ZYP will stay on the mold. Brush and tap out the excess.

Subsequent Firings

  • Apply a single coat of ZYP and allow it to dry.

About Spraying

  • Work outdoors or in a well-ventilated area, wearing a dust mask for particulates.
  • Shake the can and listen for the ball to rattle. Once it rattles, continue shaking for approximately 90 seconds.
  • Hold the mold about 10˝–12˝ (25–30 cm) away from the can. Wear a glove if you hold the mold while spraying—or set up a box/spray booth where the mold will be at a good angle to spray while keeping the can upright.
  • Hold the can UPRIGHT while spraying. This helps keep the Boron Nitride particles in suspension.
  • Apply in a sweeping motion and try to keep the application dry. If a wet spot develops, stop and allow the mold to dry for a few minutes.

Cleaning the Casting

A small amount of ZYP may remain on the glass. Washing with Bon Ami or another mild cleanser will remove the residue.


A small amount of ZYP may remain on the glass. Washing with Bon Ami or another mild cleanser will remove the residue.


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Revised June 4, 2021.