12
3. Now insert and tighten the tube connecting knob to
secure the tube in place (
Figure 19).
4. For the XX14g and XX16g, before assembling the rest
of the optical tube, it is recommended that you install the
counterweights on the rear cell so that the tube, when
assembled, will be properly balanced rather than front-
heavy. (The XX12g does not utilize counterweights.)
Without counterweights, the fully assembled tube could
swing forward rapidly, possibly damaging the tube and
mirrors.
There are six counterweight disks for the XX14g and nine
for the XX16g, each weighing 2.2 lbs. For the XX14g, two
counterweights are to be threaded onto each bolt, while
for the XX16g three counterweights should be installed on
each bolt (
Figure 20). Tilt the lower tube section as need-
ed to access the counterweight mounting bolts on the rear
cell, and thread the counterweights onto each of the three
mounting bolts. Spin them clockwise until they stop.
5. Now, attach the four truss pole assemblies to the lower
tube section. Connect the eight captive clamping knobs
on the ends of the pole assemblies to the lower truss sup-
Focuser
Figure 20.
Installing counterweights (XX14g and XX16g only).
Thread two (for XX14g) or three (for XX16g) 2.2-lb. counterweights
onto each counterweight mounting bolt for proper tube balance.
Figure 21
The clamping knobs on the ends of the truss pole
assemblies thread into the holes in the lower truss support ring on
the lower tube section.
Lower tube
section
Lower
truss
support
ring
Clamping
knobs
Truss pole
assembly
Counterweight
Counterweight
mounting bolts
Figure 19.
Secure the tube to the base with the tube connecting
knob.
Tube
connecting
knob
Altitude
motor/encoder
housing
