If we need a plastic part which the thinkness is only 0.45mm, this plastic part need mirro polished completely, please tell us if the plastic shrinakge is 1.5%,then after milling and before polishing, we assembled the core and cavity, how much the distance should be between the core and cavity?

1.The distance between core and cavity should be 0.45 * 1.015mm this distance is after the final polishing.