Finally started on my obs

[Chris]

You've clearly grafted very hard, and it looks fantastic as a result. Loving the pier adaptor/wine rack also!  

[teoria_del_big_bang]

23 hours ago, Moonshane said:

Obviously here ?

So that is what that is for. You learn something new everyday on this site ? 

An absolutely marvellous achievement, you well deserve a glass or two ?

Steve

Edited April 16, 2019 by teoria_del_big_bang

[mckinnell]

Moonshane my friend, just wondering, IF, as you state, you will use the top of your tripod head re the mount proper, how will you cope with the screw that goes through the centre of said mount head that fixes the HEQ mount in place?, won't there be a need for some form of space so as to be able to screw the mount up firmly? or am i missing some thing, cheers mate; i just might do the same as you propose as, i won,t be going out and about with my set up but just in the OBS.

 

                                                                                    Best regards,        Tom.

[Moonshane]

Hi Tom

In the end, my neighbour gave me a steel ring which I can use - see above.

That said they way I was going to do it was to use a piece if 30mm square section steel and replace the legs with them to a suitable length to allow the steel to be set into the concrete. That way I could always remove the head and use the tripod normally. Yes there would / will be enough gap to allow me to get a socket on the bolt I will use in place of the standard hand wheel.

Hope this helps.

 

 

[mckinnell]

Are yes, i see and understand, nice idea mate!!!.......

 

                                                             Regards,         Tom.

[nightfisher]

Any update on the obsy build

[Alan White]

Shane, glad nightfisher has prodded for an update, otherwise I would have missed your thread somehow.

What a lot of work pre Obs you have done, hat off to you on this whole project.

One question. How tall is the pier plan for above ground?
Interesting design you have, looks good.

An update would be great too 

 

[maw lod qan]

Amazing work you've done. Gives you a great feeling of accomplishment, to go along with the score muscles

[Moonshane]

Well not that much to report other than the garden is finished and I converted the chunk of metal from this

To this last weekend. Just needs painting and nuts for the rod ends to set into concrete of the pier. Hope to get the pier and hopefully the deck on which the obs will sit finished next weekend

 

[Moonshane]

On 31/07/2019 at 08:04, Alan White said:

One question. How tall is the pier plan for above ground?
Interesting design you have, looks good.


 

Hi Alan

The top of the pier will be about 1500mm which replicates my heq5 tripod at full extension with my home made 10" approx. extension. This allows me to see whole available sky from a seated position.

[Moonshane]

 

Well this weekend I hope to get the floor joists, main frame and roof framework done. I’ll be putting the concrete pier in after the floor joists are formed as this will make assessing the final height a bit easier.

I’ll show how these bits fit together in due course. The roof will be flat but in three sections, all 1m deep by 4m wide. I envisage each leaf will weigh about 50kg. I may develop a spring or counterweight system depending on the motion. The obs will only really open up to about half of the sky looking south (but uphill) as Manchester and Ashton-under-Lyne are to the north. There will be plenty of objects to keep me going, especially as I should be able to maintain dark adaptation! The front section will be on a pivot and the two rear sections will be hinged/concertinaed. That said, I expect that on most occasions I’ll not have to move the rear sections other than to lift slightly to allow the front to pivot. I’ll take some pics as I get to various stages over the weekend.

 

 

 

 

 

[Moonshane]

My design hopefully (albeit with a flat roof not a pitched roof), will be a combination of 

and

[Gina]

I'm interested to see your roof design.  Looks like you'll need substantial counterweights.  Good luck.

Edited September 13, 2019 by Gina

[Moonshane]

I am thinking more along the lines of nothing (50kg is not really much weight and most will be taken by the pivot axis pins (4 as I will have two arms per side)). That said, if required I am investigating the use of garage door springs and wire. I generally adopt a suck it and see approach to design and build. Usually things work out. 😉

[Moonshane]

Progress!

I have walls and a floor!

[Stu]

Looks fab Shane. Weather looks kind for a while so hopefully you can get it well progressed.

[Moonshane]

I have an 8" ID card tube to create the pier around the current steel probably a little higher than currently. This would need to be removed after setting.

Thatsaid I can also get as a favour a 10" ID galvanized steel spiral duct which could be left in situ and painted. I think I might go for the latter.

Ran out of timber more or less for now. Use 135 linear metres! Need maybe another  50 at least.

The decking was left over from our old deck so free effectively.

Total cost so far

About £500. I reckon about £800 total.

[Moonshane]

I made some progress in my head at least last night - I couldn't sleep thinking about the issue of counterweights and making the opening and closing of the roof less 'exciting'. I went from spring systems (like a garage door) to winches (silent work gear ones (I think they would take far too long) and finally to 'block and tackle' type rope hoists. The latter is the system I will use. This has the advantage of being light, strong and variable enough to cope with the roof design I have in mind. I'll send photos as always once I have got the thing sorted.

Next step will be to pour the concrete post and set the pier top in position (assuming I can get a sunny period at solar transit time on Saturday or Sunday. Then create the roof sections and fit into position. I am hoping that by Sunday I will have the basis of a usable obs bar the cladding which I'l order once I get the roof done. As always I would find this all a much slower process without my Mr Miyagi, father in law Ken. I will never underestimate the volume required of screws and timber, nor the benefits of an impact driver, again.

Another thing mentioned by Ken, that I had not even considered 😊 was the possibility of snow on a roof of 4x2.4m dimensions and constructed of 3x2 timber. Whilst to keep weight down, we'll still be using 3x2 for the roof panels, we will install two removable purlins in the form of 2x 3x2s screwed together.

[Moonshane]

I had a ‘design meeting’ with Ken last night and we concluded that as I am not really likely to be looking ‘back’ towards north with the scopes, we could have a more simple roof design. The one proviso is, of course, the need to polar align. Therefore we will have a single, larger hinged  rear section (hinged as it needs to be raised slightly as the top roofing sheets will obviously overlap the bottom ones). The front section will also be slightly larger but more or less as previously. This should help with both setting up and also shielding from light pollution.

I had a sit in the structure with binoculars last night and even though it is open framework, I can really see that it will make a huge difference. As I look up a 25% incline to the house, I may need a couple of removable sheets of ply to mask the lights every now and again but only when observing at certain angles.

Before weekend I hope to pour the concrete pillar and then paint the structure, but first I need to temporarily fix my mount to the current steel inner support and see where Polaris is in relation to the roof so I can establish the roof section dimensions. Then this weekend we can hopefully create the roof.

Setting out my thoughts like this will hopefully help others in their own designs, although my circumstances are quite unusual I suppose!

[Jkulin]

4 hours ago, Moonshane said:

had a ‘design meeting’ with Ken last night and we concluded that as I am not really likely to be looking ‘back’ towards north with the scopes, we could have a more simple roof design.

You'd be surprised how often I start my sessions looking N / NE, my home blocks some it is but I really would be careful about obscuring it completely. My latest acquisition was a prime example as that started off above my home and finished over my neighbours to the East.

[Moonshane]

Fair comment but the light pollution is terrible to the north (Manchester) - it literally lights the sky - and trees/my hedge virtually block the whole vista (self imposed as houses are being built to the north too.). The Beech hedge to the rear will be left to grow higher still, albeit I'll be doing a rejuvination prune to take the sides back about two feet from the obs over the winter.

[DaveS]

Just out of interest, as I'm planning mine, what size timber have you used? I have a tendency to use too big a size, lending myself in extra expense and woodworking (Wood butchery more like) problems.

[Moonshane]

I used 6x2 tanalised for the floor joists and 3x2 scant for the rest. I am trying to keep weight and cost down and for the roof, a 4m span with 3x2s will sag especially if there's snow resting on it. Therefore I'll be installing two removable 'purlins' from the back to the front, and touching the underside of the roof panes to provide support. These will be taken out when in use (and I may actually use them to prop the rear section while dropping the front - I like multi purpose!!). Good luck with your build!

[Davey-T]

You did well to find all those straight bits of CLS Shane 😂

Dave

[Moonshane]

LOL. They were all straight...........eventually.......... 😂