Making a Polysulfide Rubber Mold of a Masterpiece


This is a continuation of a photo sequence that chronicles the mold making process for casting a da Vinci horse design that was never realized while the great master was still alive.  To read the full story, click here.

FMC® Polysulfide rubber was used to make the mold of this model because the original model was sculpted in Roma Plastalina, a sulfur bearing modelling clay.  FMC® Polysulfide rubber is not inhibited by sulfur which is present in modeling clays preferred by sculptors.  No sealing agent or release agent was necessary prior to applying rubber to this model.  Cured rubber is soft, stretchy and perfect for casting wax as part of the lost wax process that will ultimately result in the piece being rendered in bronze.

FMC® Polysulfide rubbers are also archival, meaning that the molds will last many years in a mold library.

Materials Used in this Tutorial

Step 1: Applying FMC Initial Coat