I finally got started on my dobservatory build this week for the 32". I've been thinking about this project almost as long as the telescope itself. The big scope is no problem to get out and set up, even though it weighs 191kg. But I find the least enjoyable part of observing is packing everything up at 4am in the middle of winter when there's ice stuck to everything. Having the observatory is going to be a treat, as all you obs owners already know.
I expect it will take me a few months on and off to finish the build, so I'll post a few photos of the progress as it happens. I'm enjoying the cool temperature much more than the extreme heat wave I endured during January while building the shed on the property. Between that and the brown snakes, I'm surprised I'm still here.
First few days of progress. The obs is elevated 800mm to get out of the near ground seeing effects which the big telescope is more sensitive to. I'm going to build an isolated pad for the dob to sit on, which will be 50mm lower than the floor height, so drops the eyepiece height a little more.
The floor system is posts set at 700mm to 1000mm in the ground, then bearers and joists attached with some nice James Hardie 22mm Scyon exterior floor sheeting. The dob pad flooring is going to be 18mm compressed concrete sheet. All the materials have very low thermal mass.
The sidewalls will be 900mm high so the dob can see over it. I'm making a steel frame roof and sidewall that will roll off the 900mm high timber wall. I got a great idea from an engineer friend in the US who built a ROR obs. He used roller bearings located inside ezy strut channel as his ROR system. I like the idea because the roof is captive and can't separate from the base of the obs.
Good to see the progress Allan. Seems you have moved the location to behind the shed or has all the grass died off? I have heard the drought is bad out that way.
It’s very close to your imaging field Glen, so I might have to find you a new spot next time.
I started on the dob pad today, in the centre of the observatory. I’ll build that while I have room and then lay out the joists around it. The four big posts are almost one metre in the ground and have used 400kg of concrete. It feels very solid, and I hope the view through the eyepiece is the same.
Another week of building completed. I can testify that it is still fairly dark and very, very cold at 6:30am when work begins. I'm also reviewing my labourers rate as I think he's been slacking on the job.
The dob pad took two days to build, by the time I got the four big posts concreted in the ground with over 400kg of concrete, and then all the frame work constructed around it. I've carried this idea around with me for a couple of years now, and I'm happy it's turned out so nice and solid.
Allan,
Just read about the captive wheels in C channel...
I used this up at Heathcote and I use it successfully on the Mainsail ROR which houses my NEQ6/ C11.
Recommended.
The dob pad took two days to build, by the time I got the four big posts concreted in the ground with over 400kg of concrete, and then all the frame work constructed around it. I've carried this idea around with me for a couple of years now, and I'm happy it's turned out so nice and solid.
Nice progress, looks good & at least one of you is keeping fit during construction.
Quote:
Originally Posted by Merlin66
Allan,
Just read about the captive wheels in C channel...
I used this up at Heathcote and I use it successfully on the Mainsail ROR which houses my NEQ6/ C11.
Recommended.
Sort of like a very large version of slides for car/camper fridges are a great idea.