In our case, we measure cams with a device that can read to within 0.000001" - we can detect even the slightest surface anomaly such as "pick off" where the wheel is lifted off the ground cam lobe. When you can measure values like that, you see pretty much ANY deviations that may develop in the cam profile.
Grinding oversize masters for a tracing style grinder at 4:1 or 5:1 normal size is a well known trick. IF there is an error/deviation in the profile, it will be diminished by about the same proportion when you "shrink" it back to size.
In our case, our masters start out as a 6" dia blank and then you cut in to the part to create the base circle and therefore generate lift. On small masters such as what you're using, you can probably get away with 1 deg cutting intervals when you cut your masters.
In our case, we found that you need to use a MUCH finer interval in order to generate a smoothly grindable/dynamically stable profile.
Again, for model engine use, your system is surely at an unparalled level of sophistication and/or development - I am fascinated by the device as I own and run a "real" cam grinder. However, I can assure you from our experiences in the business that when you scale things up to run full size engines, especially those at racing engine speeds, the requirements go up about as fast as the level of complexity.  |