Jack Tiefenbrun had formed Castle Precision Engineering (Glasgow) Ltd some 15 years earlier. Hamish Robertson had a company called Thermac in 1967, which became Ariston in 1970, and Ariston Audio in 1973. In 1970 Jack's son Ivor formed a friendship with Hamish. In 1971 Ivor made a prototype turntable with a ball bearing, and then went to Israel. While Ivor was away, Hamish changed the ball bearing to a single point bearing. Robertson's company Thermac then ordered forty of the turntables from Castle Precision Engineering Ltd. In 1971, and now operating as Ariston, Hamish showed the turntable under the model name RD11 at the Harrogate show, and set up a distribution network with C. J. Walker and Company.