A request for help - Cylindrical Bearing Equatorial Platform.

[MikeMS]

Dear All.

As I did not understand the maths I have plundered into this and made a start cutting the plywood. To complicate matters I am going for two circular discs for the top and bottom plates and I have cut two parts of a circle with 52 cms and 33.2 cms radius for the bearings.

I have strips of aluminium and rollar skate wheels to build.

Anyway, I very much doubt that the measurements of the bearings and the location between the top and bottom plate will be right first time. If I was to get some threaded bar and connect the two bearings together, could I adjust the distance between the two to correct the location while looking through the eyepiece of the dobsonian to align it? And would I be looking for drift north and south of the eyepeice? East and West would be down to the motor speed.

Edit. I should add, I am looking to get the bearings relative to each other with regards to their diameters more than correct an error in the calculations. Of course if you went too far one way or the other the circumferences would be wrong.

THanks in advance.

Mike MS