My son bought a cam fixture from Mario Andretti's 3n1 race shop in NJ where we bought his sprint car fixture. It has 4 pizza cutter looking wheels with precision bearings. we put a shaft on it and spun it. Walked out of the room and came back It was still spinning. If he didn't take it to the new shop I'll get a picture of it. Home made but pretty cool with over lapping pizza cutter wheels. Fitted with sliding and adjustable dial indicator . Marios. old shop had some pretty cool equipment. We came home with some unique tools.