Mounting pier


The mounting pier comprises a central 120mm diameter aluminum pipe and three triangular legs built out of standard aluminum extrusion profiles. One of the legs is adjustable in height in order to align the polar axis. With this feature the mounting pier can be used at different locations in my back-yard. At these positions there is a small metal receptacle to which the end of the adjustable leg accurately fits and a metal block that acts as a stop and datum for one of the other legs, determining the RA-alignment. The top side of the pier carries the German mount.


Images below give some more impressions and details. From left to right:
  • The mounting pier with the German type equatorial mount. The controller for the German mount is attached to the west leg of the pier. A box on one of the covers holds a set of eye pieces.
  • The three legs of the mounting pier are interconnected with profiles that act as struts.
  • The bottom part is normally covered with triplex shields that, during observation sessions, are used to locate miscellaneous part (caps, eye-pieces).
  • This is a more detailed photo of the connection of the legs to the central pier.
  • The extreme of the 'North leg' contains a piece of M8 thread, knob and lock. The lower end accurately fits to a metal receptacle fixed at the observation location. Polar alignment (in terms of declination) is done by adjusting the length of this M8-foot. The photograph shows the extreme of the North leg just hovering over the metal receptacle.
  • To fully determine the polar alignment, the foot of the east leg is pressed against a mechanical stop, also fixed at the observation location. The photograph shows the east leg not yet pressed against this mechanical datum.
  • Under the cover, on the North leg, is a position where an accurate bubble spirit level (0.1mm/meter divisions) can be placed to facilitate polar alignment of the North leg, when needed. The construction of this feature is shown in the lower left of the photograph.
The mounting pier with German mount,covers and mount controller
Lower part of pier with covers removed
Lower part of pier with covers
Detail of the mechanical connection of the legs to the central pier
Detail of the height adjustable 'North leg' and fixed receptacle
East leg and datum
Acurate leveler for declination alignment