An advanced cutting trajectory algorithm for laminated tooling

Purpose - To provide an advanced cutting trajectory algorithm for the profiled edge laminae (PEL) rapid tooling (RT) process, which is ideally suited for large-scale dies and molds. The process involves assembling an array of laminae whose top edges are simultaneously profiled and beveled using a line-of-sight cutting method based on a CAD model of the intended tool surface. Design/methodology/approach - The cutting profiles for an individual tool lamina are based on intersection curves obtained directly from the CAD model, and generated with exact geometrical accuracy. Two adjacent slice profiles, which define a lamination's top edge and are represented as polylines, are stitched together using an adaptive surface reconstruction algorithm. A cutting trajectory algorithm then develops a series of suitable cutting vectors (i.e. position and cutting direction) that minimize abrasive waterjet (AWJ) cutting errors due to non-uniform motion and variations in kerf geometry resulting from process parameter variations. The proposed cutting trajectory generation process is demonstrated virtually for an actual production tool. Findings - The proposed algorithm yields well-behaved AWJ cutting trajectories for individual lamina used in a PEL tool that are better than those obtained using any other algorithm found in the literature. Research limitations/implications - The algorithm is intended for use with AWJ cutting of PEL tool surfaces. Suggested future research includes assessment of the algorithm for other lamina cutting methods including laser cutting and wire-type electro-discharge machining, extending the algorithm to handle conformal cooling/heating channels and internal cavities, and application of the algorithm to several industrial tool case studies. Practical implications - The algorithm generates cutting trajectories directly from CAD geometry that are ideal for AWJ cutting of profiled edge lamina. It will simply make industrial implementation of the PEL RT process easier. Originality/value - This paper provides a new cutting trajectory algorithm for the PEL RT process that is a significant improvement over comparable algorithms proposed in the literature.