Thanks for the replies. My one had come loose. I have got my self a Chrony now so will have a play at the weekend.
Be very gentle tightening the screws on the tophat… It is really easy to
deform the threads that the tophat screws onto…. Use some Loctite and
gently snug up the screws…. My tophat was set at 0.086
X2 what Jeff said. Mine was also at .086, it’s now at .069. My friends was at .093 from the factory.