I bought a 12 foot clamshell dome from Aphelion in 2004. The dome arrived nicely packed in a very large crate which was easy to unpack. The instructions for assembly were clear, and the pieces were easy for two people to handle. Since my site is the top of a hill with exposed bedrock, I decided to fabricate a steel base and anchor it into the bedrock. I poured a pier base which doesn't contact the 'wagon wheel' base. The pier is anchored to bedrock using rods which extend up into the concrete pour. A small crew of 3 people working about 6 hours was able to install the dome on top of the previously installed fabricated base. After installing the dome, a floor made of marine plywood was screwed down onto the fabricated base. All the dome pieces fit well, and there were no problems encountered during the installation.
The dome has performed very well over the years. The gel coat on the lower hatches is in perfect shape, making it easy to wax once a year to allows the hatches to slide evenly with little friction. I have never had a water leak of any sort, and it has withstood 80 mph winds. This dome has a door, which I feel is a very nice feature. The way I have it now with manually operated cranks does not allow me to exit the dome with north side hatch open. I'm looking into replacing the door with a split door arrangement which would allow me to exit. Of course, if you have the electric winches, you can close the door-side hatch, exit the dome, and then re-open the hatch with the remote control.
I strongly prefer a clamshell dome design - it is a great experience to be able to open up the sky - you can scan with binoculars while waiting for your exposures to finish! It provides a great deal of protection from wind and ground level light, even with the hatches fully opened.
Highly recommended!
Regards,
- Jim Browning