On 07/02/2011 14:39, Matt Bennett wrote: > Hardest problem to overcome > (I believe) is keeping the apex seals in operation. yes. That's the flaw Some thought a while back that some sort of composite ceramic might be=20 the answer. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .