"Astronomy as a hobby not a job"®

BUILDING A HOME OBSERVATORY... Pictures To Post This Weekend

  • The Dream of a HOMEDOME
    The problem with a dream is that if it becomes doable, all of a sudden a new reality sets in... Money! How much cash is this dream going to take. Once you get past that little brain cramp then the math starts coming into play. Then of course the next step after you have all the dollar part figured out, is convincing the other half about this "dream". Now I have been married for over 32 years and never once would consider just doing this project without consultation. Especially when we are talking any number with a comma in it. In this case two digits in front of the comma.

    So first the research. I spent six years looking at solutions. Everything from slide-off to round observatories. The biggest thing to take into consideration in my case was CC&R's. You know the rules of a neighborhood that dictate your life. So the concept of a slide-off was out, because it would definitely not be approved by the Home Owners Board of Nazis. Everything has to be taken into consideration. Diameter, Height and Obstruction of view for the neighbors. So the first step was to see if the neighbors had a problem with me building my dream. The good news is, I have been setting up a SKYTENT for about 5 years, four weeks a year and they were used to seeing a dome.

    The second step was to take pictures, examples and all that I could to the Community Association Board. It took some doing and talking but I eventually was "granted approval" to move forward.

  • The Project Begins
    I have very strict criteria for my comfort and enjoyment of my soon to be HOMEDOME. The first was "what will it be?". Like I mentioned allot of time was taken and the selection was to have a round permanent dome 10 feet in diameter, and a minimum of 9 feet high at its zenith. Everything was pointing to building my own, but I always ended up being pulled to Technical Innovations PD-10 model. It has everything I required plus could withstand the heat of the Nevada desert.

  • The Telescope and Dome Pad - Start Date: 05-Oct-2005
    I knew the biggest thing to overcome was the Pad. Without a solid foundation and one that requires non-vibrating tolerances, I made sure to approach this part with planning and then more planning. I noticed that there are many camps in having the Telescope Pier with some buffer zone from the floor area. I actually chose a simpler approach. That was to pour the entire pad with pier area as one unit. Now I know this will make some people say "no way I would do that". But I had to consider what was my goal.

    My first goal was to insure no vibration. This meant the earth has to be packed and solid. First win for me, I have 18 feet of calichi dirt. This stuff is like Adobe Brick and as hard as rock. So compacting this was futile, but I did have it tamped for about 1 hour.

    Then came the layers above the dirt. It is a simple formula, but one that will insure a solid foundation. After tamping the dirt base for one hour we then placed a 50 mil plastic vapor barrier down. Then the biggest part of the base is Type-2 aggregate. If you know the concrete business, this is the best thing to put underneath your concrete. It was also tamped for one hour to a thickness of 6 inches. After tamping is was watered three times over two weeks to help it setup. Once it setup it had a strength of 140PSI. This alone was like cement.

    The most important part of the puzzle was the concrete. I noticed almost all the sites I visited they used bag mix or driveway concrete. Not quite what I had in mind. So on 10-Jan-06 I am using 20,000PSI concrete. This means that any given inch on the surface can withstand a force of 20,000 pounds on it. To further strengthen, I used 1/4 inch wire mesh and 1/2 inch rebar. The concrete is 8 inches thick. So overall there is 8 inches of concrete and 6 inches of Type-2 aggregate. The Pad is 11 feet in diameter allowing me a 6 inch larger surface. There is a 3 foot sweet spot in the center for the pier that is 3 feet deep from the dirt elevation, giving me a total center depth of 50 inches, of the hardest concrete and rebar mix possible.

    After the concrete was allowed to setup until 19-Feb-06 (5 weeks), I did a strain gauge test with a vibration test. The result was as expected. I had a total deflection of .0001 inches with a dampening factor of less than .002 seconds. Meaning this puppy isnít moving. The test consisted of dropping a 100lb weight from 5 feet onto the edges and then the center. I then did a low level test and had 6 people jumping up and down on the pad as I was measuring the vibration and frequencies.

    In addition I also set into place one 1.5 inch and 3/4 inch schedule 40 electrical PVC from the pier to the west wall. The 3/4 inch runs from the pier location to the house to pick up electricity. I decided to use a wireless network, so no CAT5 or CAT6 Ethernet cable is required.

  • The Dome - Start Date: Scheduled 06-Mar-06
    I am still waiting with anticipation the box-from-hell with my HOMEDOME. As I am also waiting for the Pier to arrive as well. Now if you decide to order these types of items, allow 3 to four months. The Pier is from Advanced Telescope Systems. This will hold my Meade LX200 12" EMC Classic. So until then ...

  • Project Equipment and Sources Information
       Technical Innovations HomeDome Observatory
       ATS Permanent Pier
       Meade Telescopes
       Ground Zero Anti-Static Carpet
       Concrete Material Basics