New observatory project!

[malc-c]

Just wanted to chime in here on the subject of electrics.  Technically there is two methods of installing mains cable, above ground and below ground (yeah I know its obvious !).  Cable that is to be run underground, should ideally be armoured, at 400mm depth and with electrical warning tape placed over the top.  You can use the same cross section of cable (2.5mm sq) that is used in domestic wiring, so long as you are not intending to run power tools (ie like a workshop installation with lathes etc).  If you are installing mains cable above ground, then ideally it needs to be 100mm minimum above the ground, and fixed to it's own support system, either via support wire, or posts and panels.  

Now most of this is well within the ability of the person who can construct their own observatory, however, the current guidelines are that any electrical work needs sign off by a qualified electrician who will issue paperwork so that you remain covered under your insurance policy in the event of a claim. (or when / if you sell the house).   

Before everyone jumps on me, I write this from experience following my own observatory build a few years back.  I'm not a qualified sparky, and the regulations (part 17 now) has changed since, but I would advise seeking the advice, and obtaining two or three quotes to have the work done.  For me, I was lucky as I had an existing armoured cable to a garden light that could be re-used, and as it was installed some time ago meant that it complied with whatever regulations were at the time.  

Now the twist is (or it was at the time I built my observatory) that if the cable is terminated with a normal plug, and the plug has a normal 13 amp fuse fitted, it's technically classed as an extension rather than a permanent fixture and as such didn't need to comply with part-p of the regs at the time... so that's what I went with.  I have  2.5mm sq armoured cable running up to a brick built shed.  This is then connected to a junction box with a spur off terminated in an IP65 rated socket for a freezer.  Then the existing armoured cable that used to power the light is connected to the junction box in the shed, and a junction box in the observatory, which has the sockets connected on a ring.  The lot is connected to a 13amp switched fused outlet in the kitchen.  I paid £50 for the local electrician who pointed me in this direction to give it a once over, and he said it was fine.  

Having said all this, bottom line is to seek professional advice,  don't take advice from posts on a forum... unless it's from someone who is qualified, and is willing to do the job or sign off your workmanship !

[Emmanuel Marchal]

On 5/30/2016 at 20:13, LongJohn54 said:

I bought Classicbond from here - http://www.rubber4roofs.co.uk/  There are other suppliers as well.   Click the Training menu and see the videos, instruction manuals and FAQs.  I found them very helpful.

perfect. i was looking at rubber4roofs! I'll go for this.

[Emmanuel Marchal]

6 hours ago, malc-c said:

Having said all this, bottom line is to seek professional advice,  don't take advice from posts on a forum... unless it's from someone who is qualified, and is willing to do the job or sign off your workmanship !

Thanks Malcolm. I agree. electrics is one thing i won't gamble on. the electrician that put some external lights on my patio from the spur also laid the cable to the observatory. so I feel ok on that front.

[Emmanuel Marchal]

A bit of progress over the last couple weeks. The roofing EPDM is now installed. It was very easy to lay there. I'm glad i went for this instead of felt.

And i'm used red cedar for a nice finish on the cladding. Seems my wife is ok with the look so bonus point here! Now onto the electric inside and also finishing the top of the roof.

I'm struggling a bit with the roll off roof however. the walls turn out to not be exactely straight and the caster wheels don't stay in the right place. I have to think whether i need to invest in a rail/track system.

anyway, slowly getting there...

 

 

 

[Emmanuel Marchal]

Small update. the roof cover is finally complete!. now onto working the interior.

[Emmanuel Marchal]

Finally, after another month working too much, i managed to take time to build the door, install some hardwood flooring, put the pier up and bring the telescope in! Had a quick check on field of view and seems to be fine. my initial calculations were ok!

Still quite a bit to do (electrics, replace the rollers for the roof, more wood panels). but one can hope i have my first observation before end of 2016. wish me luck.

[malc-c]

I'm curious, in the previous photos you dug a hole for the pier but in the last image it looks like you've secured the pier directly to the floor.  In most cases the floor is separate to the pier so that vibration is not transmitted from the floor. and I can't see any evidence of this in that image 

[cosmojaydee]

5 hours ago, malc-c said:

I'm curious, in the previous photos you dug a hole for the pier but in the last image it looks like you've secured the pier directly to the floor.  In most cases the floor is separate to the pier so that vibration is not transmitted from the floor. and I can't see any evidence of this in that image 

The floor has been cut to fit around the base

[Emmanuel Marchal]

11 hours ago, cosmojaydee said:

The floor has been cut to fit around the base

Well spotted!

 

 

[Emmanuel Marchal]

After quite a bit more work, i now have the control room done. installed a secondary display on swivel arm so i can put it in view of the scope to help with live view. First light was last Saturday and a success. see the moon in live display in the back. Now still a bit more work to fix the roll off roof (need new track to make opening easier, still need to install second door to the control room and then waiting for clear skies!)

[edarter]

Hi, just read through this thread as I would love to do an obsy at some point. One question that strikes me though which is reelection to my own garden is the proximity of conifers etc to the building, what sort of field of view are you getting?

The ideal spot in my garden (from a build point of view) would be close to some trees and a fence, very similar to your build, but I had ruled it out as I would really only be able to observe from overhead to the south. 

Thanks

Ed

[Emmanuel Marchal]

On 12/03/2017 at 10:03, edarter said:

Hi, just read through this thread as I would love to do an obsy at some point. One question that strikes me though which is reelection to my own garden is the proximity of conifers etc to the building, what sort of field of view are you getting?

The ideal spot in my garden (from a build point of view) would be close to some trees and a fence, very similar to your build, but I had ruled it out as I would really only be able to observe from overhead to the south.

I still need to do a 360 visibility plot. but basically i can see 25deg+ in the east, 10+ in the south, 50+ in the west and 70+ in the north. so quite restricted but still ok because south is visible

Thanks

Ed

Well i have kind of the same problem as you. the conifere is in the north west which is also where London glare is so i don't mind too much. I've focussed on maximizing the south horizon, trading off access to the west / sunset / mercury/venus (can't take pics of Venus thin crescent right now which is annoying but i figured more important to get clear south horizon than nice sunset from the obsy