Zak Jewelry Tools

Castaldo® Econosil® Silicone Molding Rubber

Castaldo Econosil® Jewelry Molding Rubber is a harder, firmer but still flexible molding rubber. Firmer molds mean less variation in final cast weights, greater detail and less distortion. Molds compress less during injection and thus avoid squeezing off wax flow through thin channels. It’s ideal for filigree and other fine details. Rubber shrinkage is only 1.1%. Econosil® is a putty-like material that makes strong, tough, production rubber molds.   Molds made of Castaldo® Econosil® cut like butter, give waxes with a high shine finish and require no messy sprays or powders. Waxes self-release easily. Econosil withstands temperatures up to 660°F/ 350°C. It can be used to cast lead, pewter, tin, zinc and other low temperature melting alloys. Econosil a brick-red/brown color and is lined with special release paper on both sides. Complete instructions are enclosed in each box. Special note about shrinkage rates: The figures given for this and all other rubber molding compounds are for the rubber mold itself, not the wax pattern it produces or the final casting produced from the wax pattern. The same rubber compound molded around the same metal master model can produce highly variable final casting shrinkage rates depending on the mold maker & caster’s skill, knowledge, precision and attention to detail. Final casting shrinkage is the result of the jewelry manufacturer’s procedures. Strips measure 18" x 2 7/8th" x 1/8th" (45.7 cm x 7.3 cm x 3 mm).  5 lb. strips. Instructions.

Shore A Hardness 48-50
Vulcanizes at: 165 ̊ - 176 ̊C / 330 ̊ - 350 ̊F
Rubber shrinkage Low 1.1%
Elongation before break 555%
Tensile strength before break

897 psi

6.2 n/mm²

Tear Strength before break

111 lb./in.

19.4 n/mm

Uses Economy grade. Firm molds, filigree & thin channels, high pressure.
Color Brick red
MSDS Here