The Abbott Observatory

After countless times to setup and tear down, I found the idea of an observatory more and more enticing and not having to go through another winter of digging out I was deciding to build a roll-off design because a fiber glass structure was out of my budget. As luck would have it, a member in my astronomy club informed me he was selling his Home Dome HD-6T. Knowing the cost of the unit if purchased new and with the dome drive motor option I jumped on the offer and paid 1/3 the going price if purchased new. After renting a truck and bringing the unit home not to mention carrying the panels in the unusually high winds that day by myself I couldn't wait to start building it. I am lucky to have neighbors who are really great and didn't mind. The dome diameter is 6' which is perfect for one person and comfortable with two. I do my imaging alone most of the time, so this size is perfect for me. The platform I decided on was an 8' diameter octagon design that would allow the base to fit in the location of my yard where the sky clearance was good.

Area cleared of shrubs and nasty thorn bushes. This location was perfect to track targets rising from the East to well past the Meridian. The tall pipe designates the center of the pier and the smaller one is aligned with Polaris. The pier base is made using a 10" diameter concrete tube sunk 4 feet into the ground. Note the sandy soil of Long Island. Two feet down is dirt and past that is pure sand. Perfect for water drainage which helps prevent the ground from heaving during the winters deep freeze. Also note the rebar protruding from the sides. This is in case I decide to remove the pier from it's location. The idea is to use an engine hoist and lift the pier out of the ground.
This is the wooden form to hold the 8" diameter concrete tube on top of the 10" tube when pouring concrete. This reduction is to make clearance for the long reflectors OTA from the pier base when pointing near zenith. The nails are for centering the platform on the 10" tube. Assembled tube positions. The 8" tube height was determined by where the floor board top would be and the amount of height above that to make it the same as the Losmandy G11 height.
After mixing high strength concrete and filling the tubes, the Losmandy MA adapter was placed over the inserted J-bolt and leveled. Initial platform frame partially assembled with carriage bolts then moved into place to determine the center in relation to the pier. Notice the two thin pipes which line up with Polaris.
Time to spray paint the post locations prior to digging the holes. After the holes were dug and platform frame inserted, a cable and turn buckle was used to pull the posts evenly which greatly helped in the alignment. Measurements were taken between all 8 sides in relation to the pier to ensure it was centered.
Platform base in place. Floor joists added.
Time to dig the trench for some wiring. Note the pieces of the Home Dome in the background. I contemplated in converting the shed I built in the background to an observatory, but the ceiling is 8 feet. And here I though it was a tough root and hit it with a pick ax. OOPS! I forgot my water sprinkler plumbing was in the area. Time for a trip to Home Depot for clamps and union to repair the damage.
After the PVC wiring conduit was installed, the pier hole was filled in with gravel and pitched with sand to encourage water drainage away from the structure. Vinyl lattice was added to keep out the local wild life and a thick tarp was laid to keep moisture down.
I installed some 3/4" Styrofoam panels I had from an old project. This will help with moisture control as well as the effects of cold winters. One inch pressure treated plywood flooring screwed into place with silicon along the entire seam to prevent water from getting between the two sheets.
Oil primed and painted platform with the walls of the Home Dome installed. Notice the original one piece door. I modified it into a 2 piece door so I could exit the dome when the shutter opening was facing away from the door.

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© 2004-2006 Michael A. Siniscalchi