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____________________________ Scribner Plastics uses the rotational
molding technique to manufacture all our products.
Rotational Relative to their size, rotationally
molded parts can have thinner walls than parts made by
other processes. The low processing pressure provided by
rotational molding has the added advantage of producing
parts which are relatively stress free, as compared to
other high pressure processes. Additional benefits include to ability to tailor surface finish and color requirements to the product and the ability to use metal inserts or integrally molded threads. Reversal parts with closely spaced double walls are common and many parts can be molded with little or no draft angle. In addition to our complete line of motorsports products and shipping containers for the automotive industry, Scribner Plastics has produced custom items as varied as kayaks, bicycle storage lockers, storage tanks and floats for docks. The Rotational Molding Process In
rotational molding, a pre - measured amount of plastic
material in liquid or powder form is placed in a cavity
and the mold is closed. The molding machine then indexes
the mold in an oven where the mold and, subsequently the
plastic, is brought up to the molding temperature. As the
mold is heated, it is rotated continuously about its
vertical and horizontal axes, This biaxial rotation
brings all the surfaces of the mold into contact with the
puddle of plastic material. While continuing to rotate, the machine moves the mold out of the oven and into a cooling chamber. Air, or a mixture of air and water, cools the mold and the layer of molten plastic material. This cooling process continues until the part has cooled sufficiently to retain its shape. The machine then indexes the mold to the loading and unloading station where the mold is opened and the part removed. A new batch of material is then placed in the cavity, the mold is closed and the process is repeated.
Scribner Plastics
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molding is a plastics processing technique
ideally suited to producing relatively large, hollow
seamless parts which are partially or totally enclosed.
While this process has been in existence since the
1930's, the introduction of micronized polyethylene
provided the industry with an ideal material for the
rotational molding process.
This advantage
is especially important when considering large, load
bearing parts in applications which must provide
corrosion or stress resistance. 
The mold continues to
rotate within the oven until all the plastic material has
been picked up by the hot inside surfaces of the cavity.
The mold continues to rotate until the plastic material
densifies into a uniform layer of melt.
