My Observatory

NEW - We have moved house (Feb 2011) and I am building a new roll-off roof observatory - see here for the latest in progress photos.
Back in 2002 I decided to build a roll-off roof observatory with a permanent pier for my LX200. The following sequence of photos show it in various states of build.

1) The first step - come up with a design. I wanted the observatory to be about 8' (2.4m) square with the floor of the observatory to be elevated off the ground. I then wanted a central pier going through the floor and concreted into the ground. A pdf document for my outline design is here. Essentially its a cross lattice wooden floor with a 85" by 8" diameter steel pipe for the pier.

The total cost for the project was around £400 (UK pounds).
2) Below you can see the start of construction. I have four corner posts (5" square) concreted into the ground (about 18" deep) and the frame for the elevated floor has started.
3) Here is the finished floor lattice.
4) And the floor is now in place - I used external plywood. I have yet to cut a hole for the pier in this photo.
5) I then made  a simple framework around the outside attached to the corner posts so as to act as a frame for fixing the walls which were simple shiplap cladding. I then made a frame for the roof and some runners to sit it on, the following two photos show these in construction.
6) Here are some shots showing the finished roof assembly (I used plywood sheets to clad the roof) and it sitting on the runners. You can see the wheels fixed to the bottom of the roof that just run in channels cut out of the runners (using a router).

 
7) And with all the walls in place. These shots are from 2008 and show the signs of weathering; the plywood roof has started to warp. The observatory is now 6 years old, so for a £400 outlay that is not a bad return.

8) For the Pier construction, I used a 85" long by 8" diameter steel pipe. I cut a hole in the observatory floor and dug out approximately a 40" deep hole in the ground and concreted the pier in place. I them manufactured an aluminium plate to fix on top of the pier onto which I mounted my Meade Super wedge. This can all be seen in the following photos from 2008.

The beauty of having the aluminium plate for mounting the wedge on is that you do not need to get the pier vertical. Also over the years the ground will move which means that any slight misalignment can be easily compensated for by adjusting the locking nuts holding the plate to the pier and then re-aligning the scope. This arrangement is rock solid and I never have any problems with vibration or flexure.

Note the various bits of carpet - an essential item for when you drop an eyepiece or your CCD!

You can also see that I have a dew shield permanently attached under which I have a Kendrick dew heater strip.

Here is some detail of the Meade Superwedge mounted to the aluminium plate which itself is fixed to the pier via four pairs of locking nuts.

 
9) And that's it! Nine years later (2011) the roof and walls are showing some wear and tear but for a £400 project that is not a bad return. I intend to strip it all back this summer and replace the wood with breezeblock walls (and a wood cladding outside) and a new roof. I will post my construction photos when we actually get some decent weather in England and I can start the project.