Astro Shed

[joncrawf]

I thought I’d share my observatory build here. The build is complete much sooner than I had anticipated really – for reasons which I’ll explain. Feel free to comment and criticize, but if you spot a fatal design flaw it’s too late!

I should point out, also, that I’m a relative newbie. I had a 6” Newtonian on an AZ mount in 1986 (aged 14) which I used for two or three years until I put it to one side. Over the past three decades I’ve been a ‘non-practicing / armchair’ astronomer. But now I have an 8-year-old son who’s keen and has been pestering me to buy him a scope. I was initially reluctant as I was concerned he would expect me to show him Hubble quality brightly coloured images of galaxies, nebulae and planets – I know the limitations of an amateur telescope! But he was keen and I was beginning to feel the bug biting again. My wife & I bought him a SW 200P on an EQ5 mount for his eighth birthday and we haven’t looked back.

But it became obvious fairly quickly that if we were going to get the best out of we’d need some sort of permanent set up so that a quick 20 min session can be fitted in after dinner and before bed. I was worried the scope would get put away and forgotten about if it was a 30-minute ordeal to get it set up every time we wanted to use it.

We have a fairly large garden with good views almost all around (except to the NW) above 20^o and although we have Torquay just five miles to the South there’s no street lighting or neighbours bothering us in our back garden.

Initially the project was going to be limited to installing a home-made soil pipe pier on a 0.75m³ block of reinforced concrete with a view to installing a Pulsar Dome at some stage in the future.  

I made an adapter plate out of birch ply for the EQ5 head to on which was fixed to the pier by 3 x 1m M12 threaded bars which were concreted into the 110mm soil pipe and protruding 200mm above. Electrics and Cat5 were supplied to the pier through 40mm wastepipe underground (mousing lines left in place).

So this setup worked OK, the position was good and it was a relief to have my mount set up and ready for action. But the pier wasn’t as stable as I’d hoped it would be and the plywood mounting plate left a little to be desired – too much flex introduced by the 200mm protrusions of M12 rod.

I felt the urge to go a little further and decided to crack on and get on with the whole project done and dusted. Having more or less decided on a Pulsar dome I was having second thoughts, I wasn’t really sure that I wanted to be ‘indoors’ while enjoying the ‘great outdoors’. When Thomas and I are out with the scope we spend as much of our time looking around the night sky ‘au naturel’ as we do looking through the scope. Also, we have no neighbours immediately next door to us and no street lights shining into the garden so there was no need to consider light screening.

So we decided that a roll-away shed on a dedicated deck would be the way to go. The shed would double as a warm room in the winter and perhaps as a computer room if we decide we’d like to try our hand at imaging sometime in the future.

• The “astro-deck” and “astro-shed” were constructed over the course of 2 weekend and a few evenings.

• ·         The shed rolls on 6 x 75mm fixed casters (screwfix item 50880) rated at 70kg each. The casters run in recessed tracks in the deck. (I estimate the shed weighs 200kg)

• ·         The concrete pier base is entirely independent of the deck – no amount of leaping about on the deck causes vibration in the pier.

• ·         I replaced the home made pier with a Rigel pier from Pulsar – a big improvement!

• ·         The shed ‘locates’ snuggly onto a plywood plinth that I made to conceal the top of the concrete pier base – this means the shed can’t be tipped over (by wind or miscreants).

• ·         There are electrics and data connections in the shed, at the pier and on the deck.

• ·         A handrail and picket fence surround the viewing area – safety feature to prevent numpties from falling off the deck in the dark!

• ·         Cost approx. £1500 (including the pier)  

 

Further work / mods to be done

• ·         The red lighting is too bright

• ·         Install burglar alarm

• ·         The shed is heavy to move, once it’s built up a head of steam it’s Ok but getting it moving is hard work. Some sort of simple winch mechanism would make life easier.

• ·         The scope needs to come off the mount for the shed to be opened or closed – a bit of a miscalculation if I’m honest but not a problem so long as I’m a visual observer. If I want to have a permanent imaging setup I might need to make some adjustments to the shed.

[michaelmorris]

Great project.  You'll find that the short set up and break down times mean that you get a lot more observing done!

I fitted a dimmer to my red light which gives me complete control on the level of red light.

[JemC]

I think you have done a cracking job there,  should make it more enjoyable for you and your son,

James