During the manufacture at the Bristol Aeroplane Works, of the research Aircraft, Bristol 1880 difficulty was experienced when attempting to grind sheets of stainless steel (spec. REX 443). The size of the sheets was 7 feet by 5 feet. A surface finish of not more than 10 micro inch CLA together with a thickness tolerance of 0.0002 inches was called for. This problem was put to a number of production engineerin&researchestablishments0 one, pf which was Cranfield. It was during the research work to find a solution to the above problem that a numerical method of evaluating the performance of grinding wheels, coolants, and the machinability of different materials was developed. This has now been further developed to enable the cause of the limitations in any grinding process to be diagnosed … [cont].