Studer RM250 The Studer RM250 production cylindrical grinder was produced in fairly large numbers from 1959 to the 1980s. This superb little machine was designed for the production of small high precision components such as diesel injector needles. The work-head centre height was 60mm with a distance between centres of 250mm. Tables were electro-mechanically driven through a complex array of belts, servos and relays. Various accessories and special equipment was available for these machines such as auto-sizing equipment enabling them to be employed as semi-automated machines. These machines are generally not suitable for tool-room type work, but none-the-less could prove extremely useful in the amateurs workshop.