Smooth-On Smooth-Cast 300

Smooth-Cast 300 is a casting compound consisting of two liquid prepolymers that can be mixed and cured to form a durable plastic.

Smooth-Cast 300 is easy to mix and pour, and it offers the convenience of a one-to-one mix ratio. It readily accepts fillers and can be pigmented. Smooth-Cast 300 is superior for cold cast metal applications. Fully cured castings are tough, durable, machinable, and paintable. They resist moisture and mild solvents.

Smooth-Cast 300 consists of two liquid components, Part A (Yellow Label) and Part B (Blue Label). When combined in a mixing ratio of one to one by volume, Smooth-Cast quickly cures to a solid and durable plastic. Hardness is Shore 70D.

Applications for Smooth-Cast 300 include small to medium size sculptures, prototype models, cold cast bronze, special effect props, decorative jewelry, etc. Package of two 16 oz (.47 L) jars.

Castings can be displayed outdoors after priming and painting. Unpainted castings will yellow over time — more quickly when exposed to ultra-violet light.

Caution — Keep out of reach of children. Smooth-On Liquid Rubber and Liquid Plastics products should be used only under adult supervision. Use with adequate ventilation. The Smooth-Cast 300 prepolymers can cause severe irritation to skin and eyes, and vapors can cause lung damage. Uncured silicone rubber compound can be irritating to the eyes and skin. Remove from skin with soap and water. Flush eyes for 15 minutes and seek medical attention.

[Orozco_PNW]

Is the resulting plastic rigid and strong? I want to make a 3D printable negative of some face shields we are printing to see if this can speed up the production speed. Also, is the resulting materials easy to sterilize?

[mohamedelmasry]

is it a polyurethane or urethane resin ?