3350 W. 48^th Pl. Chicago, IL 60632-3000. Phone 773-927-3484, FAX 773-650-5853.

Source for liquid thermosets: silicones, moldmaking urethanes, casting urethanes, polyester resins, epoxy.
Fiberglass fabrics, release agents, fillers and dyes.
All products available in small quantity.

In short, crystal clear polyester resins (e.g., EP4101) are more economical, but more difficult to use and have less desirable cured properties. They are not UV stable and thus will yellow over time. Polyesters release a large amount of heat when they cure (exothermic reaction). If the casting gets too hot, it will begin to degrade and may bubble, turn brown or crack. This heat released on curing is the reason that we recommend only casting 1/4" thick layers. You could probably get by casting 2-3 layers per day. There is a large amount a shrinkage associated with the cure of polyester and thus you may have to polish and buff the surface to obtain a shiny surface.

Crystal clear urtethanes (e.g., Eager Plastics' CC200-series) are about 3 times as expensive for the same volume, but are UV stable and much easier to use. The mix ratio is 1:1 by volume. The exotherm is much more controlled and some products have been cast up to 12" in a single pour. The shrinkage is negligible, and as long as a smooth, polished mold is used, there is no need for buffing the surface.

Create an impressive variety of see-through castings with Eager Plastics' line of transparent dye (EP7702). See cured samples of 21 different colors in our color chart. Compatible with our polyester, urethane and epoxy systems.

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