Collecting  Photons

1) Track supports.

Early on during the design of the observatory I decided that I wanted a split roof. To me the advantages overcome the main defect of this design: possible (certain, many would say) leaks at the centre side where the roof halves join. On the plus side the roof is divided in two bits far more manageable, Each half moves only half the length of the building and therefore the suspended section the the track is shorter, and, hopefully, would require no separate support pillar. Last, the two halves can be open only a little bit, offering more protection to the scope in windy nights, which is not so uncommon at my place. The tracks sit on he outside of the two long sides of the observatory and will be anchored with long screws to the large top beam.

These supports, have the only function of aligning and supporting the tracks before anchoring them to the structure. The supports themselves must be levelled respect of the ground. Finally, the two sets, one on each side, must be at the same height.

2) Aligning the supports

The supports are aligned with a bubble level. This is an important operation, and I tried to get as close as I could to horizontality.

3) Mounting the half tracks

Each half track is made with a 3 m long beam of laminate pine wood. This s far more expensive of the wood I used in the rest of the building but it is far more stable and it is perfectly square and straight, something that can't be said of anything else! The track was completed by gluing and screwing a smaller beam on the side to obtain the L shaped profile.

The track is carefully anchored to the top beam of the structure with long passing screws. Given the short length of the overhanging track, I was able to dispense with a support to the ground and instead I opted with a 45° brace discharging the weight of the open roof on the sides of the building.

4) Supporting the half tracks

The lateral braces neatly sits inside specially shaped supports, designed to distribute the load of the track and roof on a large surface. The tracks are very solid they support my (conspicuous) weight from the very extremity without any apparent effort. This load is far less that the weight of the incoming roof.