Clear Skys observatories are constructed with high quality marine grade fiberglass materials and non-corrosive hardware. The basic
structure walls and dome, are constructed from fiberglass. The standard color is called white-white and has been selected due to its
low emissive properties. This means it is very reflective and has a low rate of light and heat absorption. This helps keep the
observatory and equipment cool during the day. The dome rotation operates with a three-point roller system using six rollers. Three
rollers support the dome and rotates on the base surface. Three additional rollers keep the dome centered on the base(walls). The
rollers are made of a soft rubber with Delrin bearings. This produces a low friction system resulting quite operation, with a low
force required to rotate the dome.
Dome:
The dome is constructed from a one-piece mold for strength and durability. By using a one-piece mold, we have eliminated all seams in
the gel coat for a better finish. The dome rides on a roller system, which runs very smoothly and true.
Height 45 Inches
Inside Diameter 90 Inches
Slot width 24 Inches
Assembled Observatory:
Maximum Outside Height 108 Inches
Height Inside 106 Inches
Maximum Outside Diameter 112 Inches
Existing Cement Slab
If your observatory is to be mounted on an existing cement slab, you must anchor the observatory to the slab after the assembly is
complete. We recommend the use of cement anchors as shown in Fig. # 1 and located as shown in Fig. # 4. You should use
silicon caulk between the dome and cement to improve sealing from water migration.
New Cement Slab
Mounting the observatory on a new cement slab we suggest that the slab be poured with a taper from the center outward for drainage. You
should use silicon caulk between the dome and cement to improve sealing from water migration. Your observatory must be anchored to the
slab after the assembly is complete. We recommend the use of cement anchors as shown in Fig. # 1 and located as shown in Fig. # 4.
Installation Using Paver Bricks
Mounting the observatory using paver bricks, a new cement slab ring should be poured to anchor the walls. The paver bricks are an
excellent method of installation, the observatory walls were designed to accept paver bricks recessed into the lower flange see Fig. # 2.
The paver bricks require a base of slag sand 6 inches deep, tamped. You can purchase a paver brick circle and the finished job looks
very impressive. Your observatory must be anchored to the slab ring after the assembly is completed and before the paver bricks are
installed. We recommend the use of cement anchors as shown in Fig. # 1 and located as shown in Fig. # 4.
Installation With No Foundation
Mounting the observatory without a foundation is not recommended. If you choose to install your observatory without a foundation,
drive some type of anchors into the ground and attach the walls to the anchors.
Installation On a Wood Deck
The mounting of the observatory on a wood foundation requires anchoring the base to the wood foundation using eight-½ inch bolts nuts
and fender washers. See Fig. # 3.
FIGURE #1 Anchoring to concrete pad
FIGURE #2 Anchoring for paver bricks
FIGURE #3 Anchoring to wood deck
FIGURE #4 Plan view of wall sections and anchor placement
Leveling
Check the level of the walls, it should be as close to level as possible.
Anchoring to Foundation
At the base of the walls there is a flange that extends into the dome eight inches, this is for the purpose of mounting the observatory
to the foundation. Drill 8 evenly spaced holes and secure the base to the foundation using ½ anchor bolts with fender washers. See
Fig. # 5. You should consider putting caulk between the base and the foundation to help keep water from migrating under the
observatory.
Dome Installation
The Dome comes pre-assembled, this will take three persons. Pick up the dome from three evenly spaced locations and place it on top
of the walls with the guide rollers out side the upper wall flange.
FIGURE #5 Plan view of wall section layout
FIGURE #6 Plan view of wall sections and anchor placement
FIGURE #7 Plan view of wall sections and anchor placement
Site Preparation and Assembly for Dome & Roof Ring OptionBack to top of page
Typical Section
The typical section (Fig. #8) shows the interface between an owner built structure and the Clear Skys Dome & Roof Ring. There are
several items to note. The datum used to set the height of the roof ring on the roof is also the mounting plane. The mounting plane
should be as flat and horizontal as possible. The ring has a 1-1/2" thick plywood core for securing the ring to the roof. This core
is imbedded into the fiberglass ring to provide a waterproof system. The core is 8" wide and runs the full length of the roof ring
section except in the area where the rings are assembled to each other, the roof ring is divided into for sections for ease of shipping
and installation.
FIGURE #8 Roof Ring Typical Section
Water management for the dome and roof ring is inherent in the design. Water sheds off the dome and away from the roller wheel
assembly through the use of a gap seal. The water then sheds off the roof ring onto the roof. The owners roof must have at least
a one half inch gap to the drip edge of the ring to ensure proper drainage. As mentioned above, the ring is fiberglass and encloses
the mounting plate. It is recommended to have the roof designed in such a way that it resists water intrusion at the mounting face.
Also recommended, the roof ring should have a bead of caulk applied between the mounting face and the roof (not shown). Height of
the lower edge of the shutter opening. The owner should determine how high they would like the lower shutter opening to be relative
to their telescope. Add the distance from the floor to the ring mounting face then add the distance from the mounting face to the
lower edge of the shutter opening. This should correspond to the height of the telescope and the angle to the horizon.
Roof Ring Foot Print
The roof ring foot print is shown in figure #9. The inner edge is referenced in the typical section (Fig# 8). The installation of
the ring should be as level and flat as possible to avoid uneven operation of the dome in rotation. Please note that the shutter
extends past the roof ring by 16 inches and swing clearance must be designed into the owners structure.
Roof Ring Assembly
The roof ring arrives in four sections. The sections must be assembled to each other before the ring is attached to the roof. Care
must be taken when moving the assembled ring to avoid breaking the joints. When assembling the ring sections the mounting faces have
to be flush with each other. It is recommended to use caulk in between the section joints to create a watertight joint. Four
fasteners are used at each joint, two through bolts & nuts and two lag bolts. The lag bolts are secured into the wood mounting core,
see Fig# 9.
FIGURE #9 Roof Ring Foot Print & Attachment
Interfaces
Pier LocationBack to top of page
If you plan on installing a pier inside your observatory the following guidelines may be helpful.
Elevation
The pier elevation for your telescope can be determined by setting your telescope inside the dome on its tripod. Next, check your
ability to see as low to the horizon as you wish, then measure from the ground to the base of the mount. This measurement would be
the pier height required.
Location The pier should be located so that the pivot point of the declination axis is in the center of the dome. For
an equatorial mounted telescope the pier is located in the center of the dome. For a wedge mounted telescope the pier is offset to
the south so the pivot point of the declination axis in the center of the dome. Alternative wedge mounting, the pier is located
in the center of the dome, and an offset top plate is used. This offset top plate locates the wedge to the south of the pier centering
the declination axis in the dome. This method allows some versatility, allowing you to change telescope mounts from a wedge to an
equatorial by replacing the piers top plate. This is easier than relocating the pier.
Vibration Isolation
The pier should be isolated from the floor or surface you stand on, this will reduce the amount of induced vibration caused by
your movements.
