My flip top observatory

coldlegs (Stephen) · #1 09-10-2011, 11:48 AM

My flip top observatory is finally a reality. It turned out to far easier than I had expected. I started with this 2.26M x 2.26M shed ...

ABSCO Premier Garden Shed Model 23231G
http://www.absco.com.au/products/index.php?c=14&p=36

Added options
key lock door handle
concrete bolting pack

basic cost $662.73
Total cost including options/gst and discount $793

The local distributor had the option of either free installation or pre-assembled sections. I chose the pre assembled sections so the roof sections could be pre-modified. A word of advice here. It's a very good idea to have a mate helping and holding things up whilst you screw them together. Doing it sole is definitely awkward!!
The roof is an important structural element of this shed and without it the sides need brackets on all four corners both top and bottom (as shown in the pictures) to give them enough strength to basically stand square. Once they are in, the unit is quite square and rigid. The hinges were dead easy. Had some shipping pallet wood that was exactly the right thickness (about 31mm) to fit.
To open the roof a pole with a hook on it is used to push the upper most roof section first then the lower section. The first time I closed it there was quite a bit of noise with metal coming to rest on metal which would probably disturb the neighbours at 2am in the morning so I added some adhesive weather proof strip along the top edges. It's now very quiet. In fact I think I can open and close it without making a sound. The roof sections are quite light but when opening the leverage can get quite high so I rest the pole against the side and gently lower the section down until the chains take up the slack.
I used some galvanised pipe clamps to hold chains and wouldn't recommend using them as they are too flimsy. You need to use a solid flanged eyelets or some thing else as strong.
Wind gusts will be a problem with the side that is almost vertical so I'll have to find a way to tie it down when open. Probably bungee cords.
You might be wondering why it's located in the corner. Well the rear side is the Adelaide city centre direction (light pollution heaven) and the shed already blocks of the west so the idea is to open up as much of the east and north as possible. I should have at least +/- 45 degrees from vertical in any direction so I can't complain too much. Many people have a lot worse!
You need to watch the pier height as my 10 inch Meade (sct) on an eq6pro mount came within about 10cms of the roof (2m high). The pier is about 1m high.
If you are thinking about an observatory then this might be a reasonably easy and cheapish way to go.
Cheers
Stephen

coldlegs (Stephen) · #2 09-10-2011, 11:49 AM

Some more pictures

koputai (Jason) · #3 09-10-2011, 12:22 PM

Aha! I was just about to ask in your pier thread where it was bolted?

Well done again!

Our systems are remarkably similar. Over-engineered home made pier, EQ6, Meade 10 inch. (well I pick my Meade up soon)
I've never owned an SCT before, so it will be new stuff to learn.

Cheers,
Jason.

mswhin63 (Malcolm) · #4 09-10-2011, 02:27 PM

Brilliant work, this is exactly the kind of Obs I need for my rented place. I will consider a false floor to fix to the ground but all aspects are well done.

vanwonky (Dave) · #5 09-10-2011, 03:35 PM

Nice work Stephen. Doing something like this interests me as well. I assume that leaving the scope in the observatory is one of advantages but I would wonder what a summer of Perth weather would do to it. Especially if it gets into the high 30s and above it would be pretty toasty in that tin shed!

coldlegs (Stephen) · #6 09-10-2011, 04:59 PM

Quote:

Originally Posted by vanwonky

Nice work Stephen. Doing something like this interests me as well. I assume that leaving the scope in the observatory is one of advantages but I would wonder what a summer of Perth weather would do to it. Especially if it gets into the high 30s and above it would be pretty toasty in that tin shed!

Dave
The shed is cream coloured so it should reflect most sunlight. I would expect it to get about ten degrees above ambient, maybe 45-55C. A bit toasty. Anyone got any ideas how to simply insulate it??
Cheers
Stephen

ChrisM · #7 09-10-2011, 10:37 PM

Nice work Stephen. You've achieved a good quick result without too much messing around. May you spend many pleasant hours in the shed!

Chris

ZeroID (Brent) · #8 10-10-2011, 08:19 AM

Thanks for this . I'm about to do similar with a tin shed but a few differences. I have a huge 4 meter square slab of concrete (10 tonnes !! ) which will be the base it and the pier sit on but I am building a floating platform above it for a couple of reasons.
1. The 'Sewer Pipe Pier' will be bolted down to the slab and this way I can get some isolation from it. Also the pier will be quite tall and I will be able to reach the scope easier
2. The platform will also keep all the equipment above the inevitable water that wil flow during rain etc and will have several damp barriers plus allow airflow beneath.
3. I plan to use a flat roofed shed and swivel the roof sideways resting in across the last 700 mm and keep the PCs etc under cover from most dew etc.

Good advice on the corner angle bracing. I figured it woould be critical, those sheds are not particularly robust structurally. I'll also have some 2x3 timber bracing along roof lines where your hinges attach just to keep it straight.

Just shows you, you dont have to spend a fortune to get it done.
I'll post some pix when I get some construction seriously started.

aworley (Alex) · #9 10-10-2011, 11:45 AM

Thanks Stephen .... That is a great inspiration.....could the roof go all the way down if the hinges were the right sort?

Also, found this old thread on IIS....
http://www.iceinspace.com.au/forum/a...hp/t-4788.html

Alex

PeterM · #10 10-10-2011, 01:11 PM

Stephen that is an excellent job well done.

As far as insulation the first thing I did was to paint the roof with 2 coats of silver ormonoid bitumen paint from Bunnings. This has had a huge impact on reducing the heat transfer into the observatory. I redo it about every 3 years. Another idea I use in summer is to have sunshade cloth on the Northern and Western walls. From Bunnings you could use the Cooleroo outdoor sunshade roll up blinds. They retract on a spring, so by bringing them to ground on an angle to the shed wall you allow for cooling from the material and the air gap. In winter you simply retract them.
Even if you line the walls and insulate them I think you will find the sunshade keeps the walls and the inside significantly cooler.
I also have a small caravan air vent ontop of the roll off roof, this helps significantly.
My Observatory is no hotter inside than outside on real stinker days and is often cooler by a few degrees.

PeterM.

coldlegs (Stephen) · #11 10-10-2011, 02:12 PM

Alex
Can't think of any reason why the sides could not fold all the way down. You would need to screw the hinges to the top of the rail instead of the side and the wood may have to be a different shape to fit but it's doable.
Cheers
Stephen

Quote:

Originally Posted by aworley

Thanks Stephen .... That is a great inspiration.....could the roof go all the way down if the hinges were the right sort?

Also, found this old thread on IIS....
http://www.iceinspace.com.au/forum/a...hp/t-4788.html

Alex

coldlegs (Stephen) · #12 10-10-2011, 02:14 PM

Thanks for the great ideas Peter. I had no idea you could get "silver" bitumen paint. I think I will do all three ideas asap.
Cheers
Stephen

Quote:

Originally Posted by PeterM

Stephen that is an excellent job well done.

As far as insulation the first thing I did was to paint the roof with 2 coats of silver ormonoid bitumen paint from Bunnings. This has had a huge impact on reducing the heat transfer into the observatory. I redo it about every 3 years. Another idea I use in summer is to have sunshade cloth on the Northern and Western walls. From Bunnings you could use the Cooleroo outdoor sunshade roll up blinds. They retract on a spring, so by bringing them to ground on an angle to the shed wall you allow for cooling from the material and the air gap. In winter you simply retract them.
Even if you line the walls and insulate them I think you will find the sunshade keeps the walls and the inside significantly cooler.
I also have a small caravan air vent ontop of the roll off roof, this helps significantly.
My Observatory is no hotter inside than outside on real stinker days and is often cooler by a few degrees.

PeterM.

PeterM · #13 11-10-2011, 12:02 PM

Here's a link to the Silvershield paint
http://www.pscoop.com.au/newweb/msds...lvershield.pdf

PeterM.

coldlegs (Stephen) · #14 11-10-2011, 06:27 PM

Thanks Peter. Got some from bunnings. Just started a new thread about the physics of using the stuff inside the shed in "astronomy and amateur science" section (http://www.iceinspace.com.au/forum/s...ad.php?t=81697). Curious about using it inside the shed. Have a look.
Cheers
Stephen

Quote:

Originally Posted by PeterM

Here's a link to the Silvershield paint
http://www.pscoop.com.au/newweb/msds...lvershield.pdf

PeterM.

Neil · #15 13-10-2011, 06:13 AM

Great idea, looks great, i,m wondering what you have attatched to your viewfinder ?

coldlegs (Stephen) · #16 13-10-2011, 11:00 AM

Quote:

Originally Posted by Neil

Great idea, looks great, i,m wondering what you have attatched to your viewfinder ?

Ok Neil I confess. It's my “butt ugly” finder/guide-scope using a long exposure SPC900NC in the little box. Discovered that if you screwed the standard SPC900NC lens almost all the way in and placed it directly against the Meade finders lens you could get very good focus. So took the SPC900NC lens off, placed it in the middle of the Meade lens and used silastic to set it in place then screwed the SPC900NC back on and focused on some stars. When I had exact focus, applied hot melt glue to set it in place. At the very least it's a good finder scope but I'm hoping to use it as a guide scope as well. At least whilst I'm practising guiding. Also have silver painted the side of the shed to minimise heat gain. See photos.
Cheers
Stephen

Neil · #17 13-10-2011, 04:55 PM

I see, very clever, I suspected some sort of guide scope, well done. I see you have a crayford style 10.1 focuser, how have you found it performs focusing while imaging?

coldlegs (Stephen) · #18 13-10-2011, 07:33 PM

Quote:

Originally Posted by Neil

I see, very clever, I suspected some sort of guide scope, well done. I see you have a crayford style 10.1 focuser, how have you found it performs focusing while imaging?

Wouldn't be without it Neil! Just set up the Mead focuser to roughly right and use the stepper to control the crayford. Don't know how I lived without it!
Cheers
Stephen

Neil · #19 14-10-2011, 04:56 PM

Great, I,ve just got one last week from Bintel, I,ve installed it ,but only used it once visually, no imaging yet. The clouds and other commitments won,t go away.

coldlegs (Stephen) · #20 25-10-2011, 07:09 PM

I think I'm about done with the observatory and am almost ready to start getting serious about astrophotography. A weatherproof 240V/10A mains inlet has been fitted to the outside and weatherproof switch-able sockets to the inside. Foil bubble-wrap type insulation has been contact cemented to the inside walls and roof which should minimise heating in summer and dewing in winter (maybe with a small heaters help). Couple of small vents fitted top and bottom to the south wall for a little air flow. Also wired up all the power supplies used for various cameras and set up the main hub for easier connection. Now all I have to do is make a few looms specific to various cameras and it should be ready for summer. Now if we could invent an anti cloud device we would be laughing.
Cheers
Stephen