Planning My Observatory - Feedback Wanted!

Hi,
We're just after moving into our new house (finally got on the property ladder!) and now I'm starting to seriously plan the construction of an observatory.
For a number of reasons I've ruled out a dome. This leaves me with some sort of a roll-off-roff shed.
As for sheds, I'm thinking of this one:
tinyurl.com/7nqrp
The main benefits of this shed are:
* Cost
* Size (10'x 12')
* All the walls are the same height making it easier to remove the roof

However, I'm wondering, which would reach an ambient temperature quicker by evening time; a timber shed or a metal shed? The metal shed would probably heat up quicker and reach a higher temperature, but it should also cool down quicker. Thoughts anyone???

So, to start the ball rolling, here's a photo and a drawing of my back garden I did up (while waiting for the clouds to part for some solar observing).
www.irishastronomy.org/user_resources/fi...Garden%20Drawing.jpg
www.irishastronomy.org/user_resources/fi...20garden%20photo.jpg

Any suggestions on where it should sit in the back garden? I'm thinking of removing one of the sheds in the left corner and placing it in there. Anyone have any thoughts on this or got a better suggestion?

As for the shed itself, is roll-off the only option? The concern I have about this is the footprint the whole thing takes up - it takes up twice the size of the shed. is there any way a hinged mechanism could be created to unfold the roof off to the side of the observatory?

Any thoughts anyone?

Michael,

I just installed a yardmaster shed a few weeks back (as a shed, not an observatory). Argos sell them. I bought their largest one for 799e. They really are great. I have considered adapting one as an observatory however looking at how its put together I'm not convinced its the best idea. I think it could be done, but not easily. You would certainly need to add extra re-inforcing around the area that you separate. If you like I'll take some snaps of mine to demonstrate what I mean, if u like. Also if you find yourself up in dublin. Why not pop over and see it. Just drop me a line first. OTOH my brother in-law bough a smaller one and one thing that struck me was the assembly was different to mine. Basically his one assembled the roof and the rest a a separate entity and then the roof had to be lifted on. (Took three of us to do it!!). It struck me that this model would be far better suited to an observatory. I dont know the exact model number, I'll check it out for you.

Dave,
It's the Yardmaster shed I'm considering alright.
www.yardmaster.co.uk/
From their "Product info"page, the roof is a completely separate unit and simply bolts down onto the walls. It's on the basis of this that I was planning the observatory. Most sheds I've seen have walls at each end which go up to the eaves making it difficult to modify.
Form what you're saying, it would seem that not all their sheds use the same construction sequence. I would be very interested to know which model no. unit you bought.

Thanks,

Michael,

I bought model 1012 its the shiplap one 285cm x 387 cm base. Its blooming huge! As mentioned it goes together with the roof being erected at the same time as the rest of the shed. The reason for this is clear. If the roof was made separately it would be ferociously heavy to lift on. Therefore one the basic frame is in place you need to the start assembling the roof joists etc. You could do it separatly I'm sure. But you would need to modify it extensively. I suppose no matter what model you get in order to add rollers to it its gonna need to be modified.

Just another option you might consider.

www.skyshed.com provide plans for a roll off observatory which you can build from the ground up. They charge for the plans on CD. However if a couple of us were interested. I'm sure we could 'chip in' for it. Not much anyway.

Hi Michael

Metal sheds certainly heat up a good bit. Probably more than a wooden shed though I have nothing to compare my metal shed with. I do know that mine gets sweltering on a sunny day, even if its cool outside. So much so that today, the laptop shut down on me!

But by opening the doors up an hour or so before observing, you should be fine.

I had the idea of converting mine to a roll-off but I'd have to get an angle grinder out to the metal frame of the roof and then probably do some welding etc. So I gave up on that idea. I don't know how easy it would be with your proposed shed...

An interesting design I came across was Phil Harrington's. This is what I'll probably eventually build myself. The whole shed moves and is just big enough to cover the scope/mount. Perhaps you could modify the existing shed? It'd save you a few bob. I know Phil made his in stages - the roll-off first and then the enclosure. Personally, I wouldn't bother with the enclosure because we don't get the weather Phil does

As for location, I guess it depends on the height of your garden walls and stuff in the distance (mountains, trees etc). Personally, I usually find myself sticking to the East, South and West and I've rarely suffered from not being able to look North (I can get Polaris though).

If you stick the roll-off in the corner, you may be limited by the wall height there though. The 8x6 shed might be good location but you'll be limited in how low you get in the East. Why not go for the lawn opposite the 8*6 shed - no need to encroach too far into the lawn. And if you do a whole-roll-off shed affair, you can roll it back onto the paving. And use the 8*6 as a warm room.

All this said, your priority is of course to get the lawnmower and strimmer out rather than observing

Here's Phil's link:
www.philharrington.net/swo/

And here's a links page to many, many more
obs.nineplanets.org/obs/obslist.html

And if you want, I have a copy of small atronomical observatories (I and II) by Patrick Moore - let me know if you'd like to borrow them.


Cheers

Dave McD

Dave Grennan,
Thanks for the heads-up re the 1012 model shed. I had assumed that the roof was still separate. This may require a rethink on my part. I'd greatly appreciate if you could post a photo of the gable end of your shed if you get a chance please. Thanks!

Dave McDonald,
You raise some interesting points there (and no, I'm not referring to your gardening control measures! )
Firstly, as for temperature, I was planning to install a a few fans. Two fans down low on one wall sucking air in while another two blow air out high up on the opposing wall. How much this would reduce the temperature by I don't know. Rolling back the roof should cool the place down quickly though as the material is very thin and so should cool quickly.
As for observing patterns, when I go observing, it's mainly between the east and the south-west.
I've seen the rolling-shed idea alright but I'm not a major fan of it personally. Walls offer places to have shelving, posters etc which you can use during the observing session. However, they do offer greater clearance near the horizon and are good for large scopes such as his. Which brings me onto one point - I do plan to invest in a large dob once the SSIA matures next year. My plan was to invest in one of these observatories this year and then stick another one onto it next year and modify it to act as one large observatory thus allowing for the low angle at which large dob would operate at. Would I be better off trying to design it correctly now for a larger scope??
Thanks for the offer of the books but I have them already.

This brings me onto one point; what is an acceptable cut-off point over the horizon; 10degrees? 20degrees??? Comments on this would be appreciated.