New observatory roll off roof

[gregbradley]

There are probably lots of threads about building a roll off roof observatory.

I have built 2 before. The roll off roof on both is a bit hard to operate. On one in particular. So I need to improve that design a lot so it rolls off easily.

I am not looking to do a remote observatory as this will be a backyard observatory on a residential block. So about 4 x 2.8 metres or so.

I'd like to mount 2 scopes to keep the idea alive of maximising imaging time when the weather is fortuitous.

Any links or suggestions to builds?

Last I looked into this electric rolling gate tracks from Bunnings seemed to be a good approach with a garage door opener to power the roll off.

Lightweight treated pine or metal batten construction would be the frame on a simple 100mm slab (not sure deep piers are really that necessary).
Cladding will be insulated colorbond sheeting (miniclad?).

Any tips?

Greg.

[xelasnave]

One thing I can suggest..do not use a cable system..I have tried and tried but nothing works in a satisfactory manner..it works but only just.... I am about to change over to a system that relies on bike chain...cable runs into the problem of a varying diameter due to more or less cable...anyways just trust me avoid cable.

Also I would suggest you think about remote control...there is no price to high that I would not pay to be able to press a button at 4 am and close up rather than going out to do that job...also I am sure if opening and closing was not such a pain at the moment I would probably open up at times where now I won't because I worry about clouds and having to close up...certainly my age and health exacerbate the matter but these days it is not a big deal to go remote and planning for it really is the smart thing to do...

My last observatory was my fifth but they have all been a roll off approach so I can not comment upon the virtues of a dome.

The garage roller door seems the way to go and I would assume that as garage doors use remote transferring the concept to your observatory should not be difficult.

Alex

[glend (Glen)]

Give the small size of your roll off roof, A simple manual push system on nylon castor wheels in angle iron tracks is hard to beat. This assumes you are prepared to hike out back to close it up. I have never minded the walk out to the observatory, even if SGP has woken me up to advise the run is complete. Don't forget the all important tie down system. Have fun.

[TrevorW]

Tie down a must when winds hit 70kph overnight in summer here, this is the one thing I fear designing the roof correctly to cater for that

[Ryderscope (Rodney)]

Hi Greg,

Following Alex's theme, it is definitely worth considering the automation of the roof at this stage. Even if you don't plan to do it immediately, at least make the design consistent with subsequent automation. At the basic level, simply being able to open and close the roof by press button is very convenient. Further to this, automating for the closure in the case of weather events can provide security when things don't quite go to forecast.

Whilst my observatory is a roll off shed, not a roll off roof, the design concept is the same - just a different way of mounting the motor and chain drive to move the roof. I have uploaded a set of videos to YouTube showing the automation of my obs if you want to pop in and check them out. My obs started out as a manual open and close and was subsequently retrofitted with the automation hardware. In my case I purchased a second hand Merlin Garage door opener and for the automation part I purchased and installed a SkyRoof Controller from Interactive Astronomy in the US. I have a weather sensor which provides data on realtime conditions so that the roof can be closed in the case of "very cloudy" and any rain event. See videos below.

Video 1
Video 2
Video 3

As an aside, I am working on the design of a micro observatory which I will build around a second pier that I have installed near the main observatory and will be making that a roll off roof with automation. My micro observatory will be 1200w x 1200d x 1450h.

CS,
Rodney

[tempestwizz (Brian)]

I utilised garage door hardware to fabricate a two level roof for the office section and OTA section of the approx 3m by 6m obs. The roof of the obs section rolls over the office section, and the rails that would support it when closed simply lift out offering unfettered view. Easily operated by hand.
In my instance, I tried to maximise my pier height for a better view, and built a raised floor section around the pier. Allowing underfloor cabling. I put in a simple double glazed window between the rooms so I could watch what was happening, and a thermal curtain in the doorway between to accommodate the cold Canberra nights. It worked very well. Utilised colourbond materials to blend in with existing garden sheds in the Canberra area.

[gregbradley]

Thanks for the replies.

One area of trouble in the past observatories was the wheels and track.

Last I looked into this there is a sliding gate track sold at Bunnings. I think they also sell wheels that fit over the curved rail.

Any advice about wheel and rail setups?

I am thinking of an aluminium frame and aluminium roof sheets with some insulation under it for a roll off roof. I don't think wind is going to be an issue but will know within 2 months.

Greg.

[TrevorW]

Myself thinking white colourbond roof sheets, over wooden frame, I'm thinking skillion not flat to allow for run off and add a solar panel

[gregbradley]

Hi Trevor,

I built a flat roll off roof at my dark site. It's simply a pine frame, sarking and Kliplok roofing and flashings. It's surprising how heavy it is.

I am planning to use aluminium 50mm section and aluminium roof sheeting to keep the weight down on this new observatory.

Greg.

[TrevorW]

Originally Posted by gregbradley

Hi Trevor,

I built a flat roll off roof at my dark site. It's simply a pine frame, sarking and Kliplok roofing and flashings. It's surprising how heavy it is.

I am planning to use aluminium 50mm section and aluminium roof sheeting to keep the weight down on this new observatory.

Greg.

Food for thought for the roof, then

[Boozlefoot]

Angle iron on top plate of obs, drilled and screwed. This provides your track for rollers such as these. They are available from bearing supplies stores, but shop around - prices vary. Metal seals or "2RS" rubbersealed, work out your weatherproofing. Small bearing, can handle a fair weight when used in multiples. Work on a tie down system possibly using inexpensive overcentre trailer tailgate lockdowns, these are adjustable.

Example only.

https://www.aliexpress.com/item/3293...ct.mainProduct

[TrevorW]

Here is a tip just watch Bunnings, I purchased a load of timber from them, not thinking anything about it that they ring up at the till based on the web prices but no they didn't now I have to go back and ask for over $60 in overcharging to be credited back, lucky I kept all the receipt and downloaded the web pages showing the price

[tempestwizz (Brian)]

FWIW, I approached the some garage door suppliers, the panel lift style. In conversation, I managed to get them to give me access to their stash of surplus, old and or recycled parts at a very reduced price. The track sections an ball bearing wheels on long axles were perfect for my task.