Modern CAD/CAM techniques together with five-axis high-speed milling allow to reduce moulds manufacturing time and costs.
Nevertheless, in order to put a mould into use, operations of manual finishing and fitting are still always required. Such
operations, performed manually by mould makers, modify the milled surfaces of moulds. Reverse engineering techniques can be
employed in quality control to evaluate dimensions and geometrical tolerances on moulds after machining and fitting. Changes
in the product’s shape are sometimes decided after a mould has already been machined. In such cases, if possible, the mould
maker directly modifies the mould. Thus the final real geometry of the mould does not reflect the one of the original CAD
model. The aim of this paper is to point out the benefits of non-contact quality control and to illustrate a procedure, based
on reverse engineering techniques, to reconstruct and update the mathematical model of the mould after it has been polished
and fit. The procedure was tested on a mould for the production of a plastic camera body that was previously inspected by
means of a structured light scanner.
Keywords CAD model - Reverse engineering - Mould - Surfaces reconstruction - Computer aided inspection