Integration of tool selection with design: Part 2: Aggregate machining time estimation

This paper describes the cutting data estimation functions of an aggregate tool selection system during the early stages of design. Part 1 concentrated on the data structures and methods required to implement tool selection within a feature-based design environment. This paper discusses the estimation of machining times necessary to assess the tools selected using machining performance related criteria. The result is a methodology comprising three main elements: (a) cutting condition estimation using tables of recommended cutting conditions for various tool types, tool diameter and component material combinations, (b) path length estimation based on procedures about how each feature type will be manufactured, and (c) the calculation of machining times considering the predicted effect that surface finish has on machining times. The results from the testing of real components were critically assessed and found to be very encouraging.