Re: FW: ATM poncet platform -- bearing dimensions

["Jean-Marc.Becker" <Jean-Marc.Becker@wanadoo.fr>]

> > The bearings were supposed to provide a level
> > platform at my 41 degree N. latitude observing site.
> > However, the completed platform acts more like it
> > was designed for 35 degrees -- it needs to be propped up
> > an extra two inches at the north end to track properly.
> > My guess is that I miscalculated the sector radius dimensions.
> > Other than the need to prop up the north end, I am very
> > happy with the performance of this platform.

The actual rotation axis is the perpendicular drawn from the southern
bearing and the plane of the sector. The radius has none importance. 

If you can close the angle between the plane of the plateform and the
plane of the sector, your problem is solved. 
The risk is that the perpendicular don't falls on the center of
curvature of the sector. 
You can do a materialisation of the axis of rotation, whith a laser
beam, fot instance. And when rocking the platform it must be steady when
aiming at a remote point on the axis.

Jean Marc