Mold Making

Everything to build a fiberglass mold and get parts off it: release agents, tooling gelcoat and resin, mold making kits, modeling clay for parting lines, and the wedges that pop a stuck part.

Release Comes First

On a new mold, build several thin coats of paste wax and buff each one, then add PVA film when you cannot afford to lose the first part. Release sprays cover touch-ups between pulls and urethane casting.

Building the Mold

Tooling gelcoat goes on the plug first, backed with isophthalic tooling resin and glass. See tooling gelcoat and resin, or a mold making kit sized to the part. The full process is in our guide on how to make a fiberglass mold.