Split roof thoughts

[jimdrever]

Hi all

I’m planning a back yard observatory. I have room for a 7”x7” structure. The problem is I don’t have enough room for a full roll off roof.

My idea is to build it with a split roof and using heavy duty drawer slides. This would eliminate the need for rail slides.

There are drawer slides rated for 200 lbs. with 40” slide movement.

Any thoughs would be appreciated?

Jim

[jimdrever]

I think 7”x 7” is not practical......maybe too small. So I think 7’ x 7’ would be a bit better?

[Floater]

Can’t help at all with the practicalities ... but I think you’ve made a good start! ?

[Moonshane]

No reason it would not work. You could always incorporate drop down struts to reduce strain on the runners for prolonged opening.

[SlimPaling]

Hi Jim ....

I also did not want to take up too much garden with a roll-off roof so I came up with a hinged split roof.

I had to make an accurate scale model of my hut first to check out if it would work .... the pikkies of the actual shed shows it firstly part built and then closed and fully opened.

The shed is 2m x 2m square and is easily opened by hand. I am well pleased with it. The right hand side roof panel has a special cap fitted that keeps the weather out making it very waterproof and has performed perfectly in some very bad rain storms that we have had.

I have seen other designs using similar ideas which seem to work well

Mike

[MarsG76]

That is a cool design... looks great

 

[jimdrever]

Mike

Very nice. Love it

How much clearance do you need for bringing down the roof?

My obs is going to be in a corner of my back yard up against a fence on 2sides. So clearance might be an issue for me.

 

 

[SlimPaling]

Jim ...

Each roof panel swings outwards by approx. 500mm each side as they hinge out.

Mike

[Skipper Billy]

Its a design that works well - very space efficient and easy to build.

Shout if you need any more details but the photos show you the basics - https://sites.google.com/view/astro-imaging/micro-observatory

PS - mine is only 4'6" square but has housed a 210mm f3.8 newt on an AZ EQ6 GT.

The only alteration I have made since the photos were taken are to make the door full height.

[jimdrever]

Thanks so much for the feed back folks!

I think the flip top is the way to go

Jim

[Bukko]

This design is genius !!

I am looking to house a couple of bigger scopes and was almost resigned to using motorised domes.. Think I need to give this some real thoughts.

One will be a 12" OO VX12 on probably the Celestron CGX-L and the second is a 16" ODK on an MEII... I have lots of space but love the clever mechanism. I wonder if it would scale up a bit, say to 2.5m square and if counterweights on the swing arms would lighten the load when swinging the roof off?

Interesting and for sure, a great alternative to the roll off roof design...

Gordon.

[SlimPaling]

The roof panels on my obsy. as quite manageable to move by hand .... but any larger and the weight might become a problem.

I had given a bit of thought about adding counter weights when I was at the planning stage ... but when I got near to completion I realised that I didn't need them. The way that I have used internal and external hinged links to lift and guide the panels as they open and close has helped get the weight distribution right.

I have never really considered how I might add some sort of motorised (or simple mechanical) methods .... there must be a way of doing it. If I am still observing when I get to be  80yrs old I may put my thinking hat on again !!!

Mike

[valefor]

How much does each side weigh? The obsy mite not like so much weight to be hanging off of both sides. Ever opened a packet of crisps. Maybe concider having a bench either side for the roof to sit on.

Mine is only 6x6 but i made it a tilt roof so the whole thing can roll off as one. Quite heavy tho. A friend of mine has a 7x7 pinicle roof and he lifts his off one side at a time. Making it alot lighter. 

[SlimPaling]

My Obsy is 2x2m square ... so just a bit bigger than 6x6'.

I didn't weigh each side panel before I put them in place (actually I put the triangular side panels in place first and then added the top panel in-situ) but I can easily handle the panels as I open & close them.

I arranged things so that my "inner" guide links (which are a bit difficult to see in my pikkies) run in a slot in the side walls of the shed and then hit a stop to make sure the roof panel does not quite reach the ground. No need for a bench. If you look carefully at the pickky of my obsy. , with the roof closed, you can see that I have added some short lengths of draft preventer on these slots .... same as that used along the bottom of household & garage doors in order to stop rain getting in ... this works well.

Mike

[valefor]

The bench i mentioned was just to take the weight of the roof off of the shed. My roof was wood and felt. It weighed alot and after a while i could see where having it down was starting to bend and break the wood of the shed i had then. So having a bench for it to sit on while down took the weight off the shed. If yours isnt that heavy it shouldnt be a problem. Yours looks alot nicer than mine did. Ive since shrunk it from 11x6 to 6x6 and its now alot better. Plus i used alot of fence posts for reinforcement

[solwisesteve]

Very interested in this concept. I've been looking towards a permanent obsy next year some time and I've been trying to think of ways to remove having to have the huge rails coming out in the typical roll-off design. One idea I had was a clam shell and the split roof is really just another permutation of that. So what do you do about the hinge points? I mean they must be under a lot of strain so what do you use at that point? A proper bearing system? If a bearing then how to do you fix it into the wall of the shed/roof? Sorry to ask lots of questions.

[SlimPaling]

2 minutes ago, solwisesteve said:

Very interested in this concept. I've been looking towards a permanent obsy next year some time and I've been trying to think of ways to remove having to have the huge rails coming out in the typical roll-off design. One idea I had was a clam shell and the split roof is really just another permutation of that. So what do you do about the hinge points? I mean they must be under a lot of strain so what do you use at that point? A proper bearing system? If a bearing then how to do you fix it into the wall of the shed/roof? Sorry to ask lots of questions.

I must admit I am the hinge links and pins out of some pretty sturdy stuff ... I probably over designed them but I wanted them to last! I made the hinge pins from 1" stainless steel bar on my Model Engineering lathe but I suppose I could have sourced some big bolts. The Hinge pins we made from 1" thick top quality marine ply. All hinge points were located on some marine plate rectangular plates ... which you can see painted pale blue on my pikkies. The position of the various hinge points had to be worked out using a CAD software program (but I could have done it using paper, compasses on pencils instead) .... I had to go through many iterations to get the best options for movement of the roof as it opened & closed. The positions of the various hinge points were very critical.

If you want to drive down from Beverley to take a close look I am willing to show you .... just need to know in advance :-)

Mike

[solwisesteve]

12 minutes ago, SlimPaling said:

I must admit I am the hinge links and pins out of some pretty sturdy stuff ... I probably over designed them but I wanted them to last! I made the hinge pins from 1" stainless steel bar on my Model Engineering lathe but I suppose I could have sourced some big bolts. The Hinge pins we made from 1" thick top quality marine ply. All hinge points were located on some marine plate rectangular plates ... which you can see painted pale blue on my pikkies. The position of the various hinge points had to be worked out using a CAD software program (but I could have done it using paper, compasses on pencils instead) .... I had to go through many iterations to get the best options for movement of the roof as it opened & closed. The positions of the various hinge points were very critical.

If you want to drive down from Beverley to take a close look I am willing to show you .... just need to know in advance :-)

Mike

Cheers.... I'm not savvy with CAD software so it would be paper and compasses for me - I did get an 'A' O level in technical drawing 40+ years ago ;-)

[valefor]

1 hour ago, solwisesteve said:

Very interested in this concept. I've been looking towards a permanent obsy next year some time and I've been trying to think of ways to remove having to have the huge rails coming out in the typical roll-off design. One idea I had was a clam shell and the split roof is really just another permutation of that. So what do you do about the hinge points? I mean they must be under a lot of strain so what do you use at that point? A proper bearing system? If a bearing then how to do you fix it into the wall of the shed/roof? Sorry to ask lots of questions.

I too wanted to not have rails. My first obsy 11x6 had a pinicle roof that rolled on scaffold poles. Very strong but ugly as sin. When i moved and decided no rails i came up with this idea. Flattened the roof and put it on an angle. Reinforced the shed more and fitted removable posts. The original plan was to also fit removable rails but it wasnt needed as the roof is quite manageable as it is.

[JamesF]

Lovely design for a split roof.  I hope it plays the theme from Thunderbirds when you open it up

James

[Gina]

Very interesting.  I looked at this sort of design when I was deciding how to make my observatory but went for a roll off roof.  I'm thinking I want another observatory but only for scope and pier not people and would be controlled remotely.  I shall consider this idea.  This is in addition to my micro dome observatory for my widefield imaging rig.  I'm looking to house an NEQ6 mount with small scope such as the Esprit 80ED.  Whether the opening roof would be remote controlled I haven't decided.  This project is something for the future and not even on the books yet.