In a method of making multi-component plastic molded parts, using an apparatus which includes two outer platens with first half-molds, and a middle platen with second half-molds interacting with the first half-molds such as to define cavities in two parting planes for injection of a plastic melt and/or a PUR mixture, one of the first and second half-molds can move in increments relative to the other one of the first and second half-molds, thereby forming different cavities in the parting planes from cycle to cycle. In a first cycle preforms are produced in respective cavities and then held in one of the first and second half-molds as the other one of the first and second half-molds moves in increments. Further components can then be injected into cavities formed in the parting planes from cycle to cycle, while another process step can be executed from cycle to cycle in free half-molds.