Apparatus and method for producing a compression molded product

A compression molding method, comprising the steps of:

• providing a mold of a first material having a first coefficient of thermal expansion and defining a cavity;
• providing a plug of a second material having a second coefficient of thermal expansion different from the first coefficient of thermal expansion;
• positioning the mold relative to the plug such that the one is disposed relative to the other along a central longitudinal axis so to provide a gap between the mold and plug with a body of a third material different from the first and second materials of the mold and plug disposed in the gap therebetween and at a first temperature such that the gap has a first volume and the body at least partially fills the gap;
• subjecting the mold and plug to a second temperature different from the first temperature so as to cause one of the first material of the mold and the second material of the plug to change in size relative to the other and thereby change the gap to a second volume different from the first volume and in a transverse direction relative to the central longitudinal axis and compress the body between the mold and plug into a molded product, wherein the change in the volume of said gap is caused essentially only by the change in temperature;
• and
• providing a plurality of pins circumferentially spaced apart from one another and extending in the transverse direction relative to the central longitudinal axis so as to fixture the mold to the plug such that the mold and plug are allowed to undergo relative expansion and contraction toward and away from one another by the pins extending through and across a portion of said gap between said mold and plug at the locations of said pins when said mold and plug are at said first temperature and permitting the size of said gap at said locations of said pins to change as said mold and plug are changed from said first temperature to said second temperature.