Firstly, when sizing for a clearance fit there is close fit and free fit. Neither is 1/2". Close is 33/64" or.5156" (13.1mm). Free fit is 17/32" or .5312 (13.5mm).
?
Secondly, the current flood of strain wave drive based telescope I pretty disturbing. Unless such a mount has high resolution encoders to take care of the period error that is exhibited by the entire length of the outer and inner splines of the drive reducers being made in China, etc., I can't see why anyone would obtain one expecting performance better than a well made worm gear reduction. I feel it shouldn't be encouraged. The justification that one can take 180-30 second images and use 100GB to stack and process them doesn't convince me otherwise.
