Orion SkyQuest XX12g Instruction Manual page 13

Registration
flats
Upper truss
support ring
Figure 21.
When the truss clamping knob is tightened, it will
clamp the truss connector against the registration flats on the upper
truss support ring.
Figure 22.
The cast-metal altitude axis trunnion on the left side
panel of the base mates with the left side bearing on the telescope
tube.
Mounting the Fully Assembled Optical Tube on
the Base
The left altitude hub on the optical tube has a dovetail slot
that slides into the altitude axis trunnion on the inside of the
left side panel (Figure 22). We recommend orienting the trun-
nion such that the threaded hole for the tube connecting knob
is facing upward. Then the telescope tube can be held hori-
zontally and just lowered into the base by gently sliding the
tube's altitude hub into the altitude trunnion on the base. If
the altitude axis trunnion on the base is oriented differently,
you'll have to adjust the angle of the telescope tube so you
can slide it onto the altitude axis trunnion. (The altitude axis
trunnion may be too difficult to rotate by hand to adjust its
orientation.)
The tube assembly is heavy and bulky, especially for the
XX14g. Get another person to help lift the tube in place if it is
too heavy or unwieldy for you to do by yourself.
1. Grasp the rear end ring of the tube with one hand and
one of the truss tubes with the other hand, as shown in
Figure 26. Lift the optical tube and gently lower it down
Truss connector knob
Truss
connector
Threaded
hole for tube
connecting knob
Figure 23.
Grasp both ends of the lower tube section to lift it,
then lower it into the base, sliding the dovetail slot in the tube's left
altitude hub onto the mating part of the metal trunnion on the base's
left side panel.
Figure 24.
bottom tube section resting vertically in base
onto the base, sliding the tube's dovetail altitude hub
into the mating receptacle of the altitude trunnion on the
base.
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