I would like to thank you all for your time and input into this little thread, I used to get e-mail notifications when a response was made to a thread but this seems to no longer happen, I don't know why, but the result is that I have been a little tardy in my response. My sincere apologies.
Thanks for the thoughts on the "wobble" I may not have made things clear. I don't think the wheel is eccentric to the shaft, it is, in fact not perpendicular to the axis of the shaft, therefore when viewed side on it moves from inboard to outboard by 10 thou. So when in mesh with the large idler the cam wheel will tend to move from back to front by 10 thou, in 180 degrees of rotation, so it oscillates. This will mean that the teeth of the cam wheel will move in an arc, in out, in out, I have tried to resist "shake it all about," but clearly I have failed... There will be points at which the apex of the tooth is pushed into firmer contact, first at the front then at the rear. Even as I write this I become more and more convinced that this is not a reliable component, I just had this vague hope that somebody out there would tell me that I'm being over fussy and therefore wrong...
I was also hoping that I might be able to visually compare the profile to a picture of a cam to confirm. I have read so much about the opening, closing and readings at max lift and their variability that I think I would despair at trying to identify a cam this way.
Many thanks for all your help.
jim