This paper addresses the manufacture of thermoplastic parts using a process whereby short-fibre reinforced thermoplastic items are injected onto long-fibre reinforced thermoplastic bases. Processing parameters are varied in order to optimise the quality of the interface bond and to minimise the warpage of the final part. In addition, numerical modelling of the thermornechanical behaviour of the part during processing is performed in order to predict the final part warpage. An uncoupled analysis in which the temperatures and displacements are determined separately is found to provide reasonable measures of the temperature profile but overpredicts final warpage by 29%. (c) 2006 Elsevier B.V. All rights reserved.