Jim Throne on September 9th, 1998

A Brief Review Rotational molding begins with -35 mesh polymer powder tumbling in a metal mold. It ends with a monolithic layer of solid polymer against the metal mold. In between, the powder tumbles against the mold until the mold temperature reaches the tack temperature of the powder, whereupon the powder begins to stick to […]

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Jim Throne on September 1st, 1998

Thermoplastic structural foams have been around for several decades now. We all know that, at the same part weight, the stiffness of the structure increases in proportion to the reduction in plastic density. And that at the same part thickness, the weight decreases in proportion to that same reduction in plastic density. Injection molders and […]

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