Molding

Spin Cast

Spin cast molding uses a disc-shaped mold that is spun along its central axis at a set speed. The casting material, usually molten metal or liquid thermoset plastic is then poured in through an opening at the top-center of the mold. The filled mold then continues to spin as the metal solidifies or the thermoset plastic sets.

Materials processed: polyurethane

Compression

In compression molding, a slug of material is placed on one half of a heated mold. When the mold is closed and put under pressure (in a press), the rubber is forced into all parts of the mold cavity, and excess rubber flows into a flash groove around the mold cavity. Rubber is compression-molded to form gaskets, seals, 0-rings, , fabric reinforced laminates, and many other types of industrial rubber goods, of almost any size desired.

Materials processed: silicone, polyurethane, rubber

Transfer

In transfer molding, the molding material is preheated and loaded into a chamber known as the pot. A plunger is then used to force the material from the pot through channels known as a sprue and runner system into the mold cavities. The mold remains closed as the material is transfered into the cavities. The thermoset material cures as heat is transfered from the mold to the material. The mold is then opened and the part removed.

Materials processed: silicone, polyurethane, rubber

Over Molding

Over molding is in additon to any of the fore mention molding methods above. An insert is placed into the mold before the bulk thermoset material is added. The thermoset can either bond to the insert or form an interference fit around the insert. As a result the insert is partially or entirely encapsulated into the part.

Materials processed: silicone, polyurethane, rubber