dhfan wrote:
Not spun, centrifugally cast. The basic principle as I understand it is that the mould is spun as the molten iron or steel is added to it. This creates a very stable, even casting.
This was the trade secret that Bristol wouldn't part with until being ordered to hand it over. They were reputedly all made at a factory just down the road from where I live.
very accurate almost. this is in use for a number of things these days. we have a firm here where I live that use a modified potter's wheel to make pewter jewelery and nic naks via centrifugal casting.
you arrange a series of the moulds in a circle radially like the engines. you start it spinning and then pour the molten metal into it. the centrifugal action spins the molten metal into the castings. as the stream would not be continuous to each and every casting somehow I can't see it as being as stable as a vacuum formed casting but it should be even. the forces making it flow into the moulds though would very likely be greater than vacuum forming