A DISCUSSION ON A CRITERION FOR THE CHOICE BETWEEN MANUFACTURING ON A POSITIONALLY CONTROLLED MILLING MACHINE AND A CONVENTIONAL MACHINE

To avoid the labour involved in ad hoc comparisons between numerically controlled positional machines and conventional machines, the authors outline a procedure which would assist in making an economic selection between these machines when considering the manufacture of a suitable component. Three principal criteria are considered, viz., the total number of com-ponents to be manufactured, the number of batches, and the complexity of the component. Formulae are derived on these bases to speed decision-making. Complexity is defined in terms of accuracy and the number of changes in the direction of the cutter, and a method of combining these is described.