Facet Rock Mold

A rock face from your own workshop

Rock formations with sharp faces arise where hard stone cracks along its joints and breaks away in angular blocks. Granite cuttings along railways, the walls of abandoned quarries or a freshly blasted slope above a road look exactly like that — no rounded shapes, but facets, edges and the shadows between them. It is this type of surface that the mold transfers to a model.

How the mold is used

Mixed modeling plaster is poured into the rinsed and damp mold and left to set. The casting is turned out while it is still damp and pliable, so that it can be bent slightly and matched to the curve of the terrain. It is fixed to the base with plaster slurry, the seams between the individual pieces are filled, and stippling with a brush levels them with the texture of the casting. Painting comes last, best with heavily thinned paints laid on a damp surface so that they run into the cracks.

Why it pays off

A rubber mold will stand dozens of castings, so a whole wall grows out of it step by step. By laying several pieces side by side you can cover any area, and by turning one casting upside down the repetition is disguised. A single mold is therefore enough for a continuous rock face of any size, with no need for ready-made resin parts.

After use it is enough to rinse the mold with water and let it dry in the open; it needs no special care. Store it flat so that the flexible material does not warp in time, and keep it out of direct sun. Mix the plaster thinner than seems sensible — a thick mix will not run into the finest joints, and the casting then loses the very texture the mold is bought for.