Complete CAD engineering files and manufacturing drawings comprising 3D CAD files and complete Shop Detail Drawings are available for $ 4,600 USD. The actual projected building cost is estimated to be about $18,000 USD for purchased components and outsourced machine shop / fabrication work. Full engineering support and consultation by us from start to commissioning is included in the price of the engineering documentation. Your local fabrication and machine shops make all your parts and components according to the drawings and specifications while you assemble your observatory on your build site.

SD-2 Rotunda: Machine grade technology is brought to bear for this unique scientific machinery. This building and machinery provides a higher level of technology and quality as compared to the average DIY home building standards, as do most other kits and suppliers already in the marketplace. All components and materials are state of the art, integrated into a unique geometric configuration to provide an efficient, spacious, pleasant and secure scientific workspace. Features:

3D Printed Concrete Dome Quadrants.
Aluminum slot cover panels.
Steel cladded exterior.
No exposed hanging cables or wires.
Brush shoe power buss bar electrical distribution.
Central electrical power panel and motion control logic.
Isometric (3) main rotation gearmotors and 3 slot cover gearmotors.
True differential telescopic motion slot covers.

SD-2 Rotunda has a wide 44 inch aperture opening. Clean lines on the exterior surfaces incorporate smooth dome head carriage bolts fasteners on the outside walls that discourages tampering and helps deny interior access to would be intruders.

Fiberglass spherical quadrants are 1/8″ thick and weigh half as much as HDPE versions. Our fiberglass dome quadrants do not need any structural internal bracing or framing whatsoever. Once fastened to the arches and dome framework, they contribute to the structural integrity of the dome.

The circular yurt type building is of conventional wood framing with exterior steel siding to provide a tamper proof enclosure that holds your expensive equipment. The steel siding can also be electrified with a non-lethal low voltage as used by cattle farmers at your discretion to further discourage tampering and help deny access where legal in your location.

**Fiberglass Dome Quadrants** are self supporting and do not need interior bracing of any kind. They are lightweight and are made in the traditional 3 ply resin lay-up method. They accept UV resistant paint to both interior and exterior. They are very temperature range tolerant and will last indefinitely without any issues.

The yurt style semi-circular addition doubles the useful floor space of the cylindrical main structure and provides a convenient location for solar panels and radio antennae of any sort on the roof as well. Shown here is a 1.2 kW solar panel array placed on the yurt roof. This would provide all the power you need for all of the utilities in the building.

The three dome rotation DC gearmotors are RPM variable comprising a gearbox turning a sprocket that engages a roller chain attached to the dome frame. The sprockets can be disengaged by hand to rotate the dome manually if so desired by means of a toggle clamp. Disengaging the sprockets also allows the entire dome to be lifted vertically off the wall.

The roller chain is fastened to the bottom inside circumference of the dome wall and below the 24 VDC power buss track. The three gearmotors are fastened to the stationary walls. Their sprockets engaging the roller chain hold the dome to the wall securely.

The dome sits on nylon rollers captured on a pipe track attached to the building wall and three sprockets engage the roller chain to fully constrain the dome to wall preventing vertical displacement in strong winds or storms.

24 VDC power is delivered to all six gearmotors in the dome via HDPE buss bar channels and brush shoes. There are no hanging cables or loose wiring.