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I wanted to write something about an observatory project that I've been working on near Spruce Knob, WV.  The actual site is at The Mountain Institute, which many of you have visited.

About four years ago, I picked a site and had a concrete pier poured using a 2’ cylindrical form which connected to a 4’ X 4’ underground concrete base by rebar. I poured a 5-meter circular pad, insulated from the pier with ½” of foam, with 48" footers around the perimeter to withstand possible frost heaves in the winter.

At that point, I got cold feet about buying a commercial dome because of the tremendous expense.  Two things then came together to encourage me to make a home built.  One, during my visits to Arizona Sky Village where I bought a building lot several years ago, I saw several successful homebuilt domes being erected.  One of my neighbors there offered his plans that he used for his 14-foot dome.  Second, I contacted a semi-retired builder, Jim Underwood, from a town near The Mountain Institute, who is also on the Board of Directors of TMI.  He became interested in the project because of its educational possibilities and offered to help.

Obviously, a 14-ft. structure could not be built off site since the shipping cost would be significant. Over the past three months, I've been preassembling the various ribs and rings for the project using a router to cut many arcs from 3/4" plywood. These were layer up in two-ply, screwed and glued to make ribs of various lengths. I made four trips to take tools, building supplies, fiber glassing supplies, and premade parts.

Thursday, June 22nd, I headed out with my camper stocked and ready to build.  Remember the history making rains then?  I watched it rain andwatched the weather forecast turn worse and decided to drive back home with my tail between my legs.  I did get a couple of things accomplished like dig out the lip of the perimeter of the pad and build a nice 4 X 8' worktable.

The delay turned out to be a blessing in disguise.  By the time the weather forecast suggested returning, June 29th, Keith Lohmeyer, a fellow Delmarva Stargazer Society member, was freed up from his greenhouse business and decided to take me up on my asking him during our April starparty to help on the project.  I would like to publicly thank Keith.  We all know what a hard and faithful worker he's been for our club.  Well, you really haven't seen him in action.  I can honestly say I had probably bitten off more than I could chew and without his hard work and construction skills, the project would have failed.

We rode up together and started the next day to build the 3 ply ¾” plywood base ring with fasteners and glue.  The following day a college student, who had a summer job working with Jim as a carpenter’s assistant, came to help. We erected the ribs on the base ring with lots of screws and glue. Then the four of us cut pie shaped pieces of 1/8” door skins to cover the 14’ wide and 7’ high hemisphere.  Then the dome was fiber glassed.  At that point, we needed to move the dome off the pad to build the walls that were 3” less in diameter than the dome.  Fortunately, a men’s church group was at TMI for a weekend retreat, and they agree to try to lift what I estimated to be a 1000 lb. dome.  About 12 of us were able to move it, after Jim had cleverly pried it up to cinder block height, about 10 feet away onto more concrete blocks.

All during this early construction the weather was threatening rain, so we had to cover things each night with a tarp, rebar pegs and bungee cords which added about 45 min each evening and each morning to daily work.  In fact, it did rain two days when we got very little done. It was always a concern that a thunderstorm would tear our tarp away and expose the delicate door skin to rain.

The wall went up in one day using precut treated plywood arcs as our base plate, 2X4 studs for framing and a cap of pre-cut arcs.  ¼” plywood was used to bend around the framework and then fiber glassed.  We were well motivated to push along, because the men on retreat were leaving the next day.  Again, they volunteered to help and about 20 of us were able to lift the dome onto the 5’ high wall with seven casters on top.    There was a heart stopping 5 seconds when we didn’t think we could take it from waist to shoulder level.  What was amazing was the co-ordination everyone showed by leaving their lifting position when they reached the wall in order to run around through the door to resume their position inside.

We then built the shutter with rollers to open and close the dome slit and built a hinged door to cover the space the shutter can’t because of the opening going slightly beyond the zenith.  We left the project 11 days after starting at a good, secure stopping point.  The dome was clamped to the wall ring and the shutter roped in place.

Over the summer, the outside will be painted an off white and the inside flat black.  The horizontal casters that will keep the dome centered over the wall casters need to be installed.  The dome and shutter will be motorized and power obtained from golf cart batteries that will be recharged by wind and/or solar power.  Can’t forget a door for the wall either.

This is a “build it and they will come” idea.  We can now use the roomy structure for our outreach programs with young people that normally visit TMI.  Having the telescope set up and the mount polar aligned will save hours of setup/takedown time.  We also plan to use it in conjunction with our youth astronomy summer camp.  Perhaps the National Radio Astronomy Observatory will find use for their teacher’s continuing education programs.  Down the road, a robotic observatory that could be used by secondary schools in WV via the Internet is hoped for.

Thanks to Jim Underwood for his encouragement and hard work, Rick Beno for his plans and consultations, Dave Martin on the TMI staff for his support, Keith for his unselfish volunteer efforts, and to Brent Bailey, director of the Appalachian campus of TMI, for his encouragement and trust.

Joe Morris  July 2006