Astrokev's Obsy Build

[Astrokev]

Well, after many months (or years) of dreaming, and hundreds of idle doodles of what my observatory could look like, I've finally taken the plunge and have started to design in earnest. I've been massively inspired by a number of build threads by other SGL members. More recent builds that spring to mind are those of Malc-C and Gina, but also Paul11 who's build I enjoyed immensely. I hope you won't mind too much if I pinch a few ideas along the way, but I guess that's partly what this forum is for - sharing ideas.

I don't think this will be a quick project as time is so precious, what with work and general family commitments, but I'm looking forward (and will probably need!) plenty of help, guidance and advice from the forum to help me keep going.

So, where to start???

My scope is a currently a 10" f6.3 Newt, which will be mounted on my new toy, an NEQ6 (currently in my shed and hasn't actually been used as yet, since I didn't have a big enough dovetail to mount the OTA until very recently)....more on that later.

My intention is to mount the NEQ6 on a concrete pier and house the whole thing in a ROR obsy, hopefully with a small "warm" room under the rolled off roof (therefore following the standard basic design there!).

So, my first (of many) requests for help and guidance - How big should I make the scope room? Big is obviously great, but I don't want to encroach too much into the rest of the garden, so really would like to know what's the smallest you think I could get away with? My OTA is around 1.5m long.

There - I've started. No turning back now. Here's hoping it all turns out OK....

Thanks for your anticipated support; I'll be posting lots of pics along the way

Kev

[red dwalf]

hI Kev,

it`s all very difficult to visualise when starting out on the build of an obsy, a lot of thought went into mine, the size i ended up with was 10` x 8` with roll of roof, which still needs proper runner and wheels for, and isa still a work in progress, but this means i should end up with a 7` x 8` scope room and a 3` x 8` warm room once i`ve divided it up which should be fine for me and maybe one other but as most of the time it`ll only be me it should be fine for getting out of the cold weather. luckily my garden is fairly large and it doesn`t look like it`s taking over the area. site of the obsy is important of course, you want the best views possiable, walls are easy enough to build, my frames are 4" x 2" doubled up at the top to support the roof.

base was made from 4" x 4" x 8` fence posts painted with bitumin paint and laid onto a waterproof barrier, type that brick layers use for damp courses.

more of the build in my thread, Rob`s obsy build in this section

one of the things i did was to use the scope and mount and see what area i`d need around it before i divided up the area into warm room and scope room.

[yesyes]

Good luck with your build also, Kev. ;-)

[malc-c]

Kev,

I'm glad my build, along with others listed have inspired you to start your own project. To answer your (first) question, ideally make the scope room as big as possible, not only to allow more than one person around the scope, but it helps when any maintenance has to be done. It just makes life a lot simpler. My scope room is approx 1.7m x 2.2m internally, and two people can be in the room without issue when the scope is slewing. Given the larger size of your OTA I would suggest you aim for similar size. I opted for a 2.4m x 4.8m external size mainly as this is the stock size timber is supplied in, however due to a slight miscalculation when laying the bricks the external size came out at 2.2m x 4.8m

Obviously I was planning to have a large warm room / office of similar dimensions, which also made the ROR section worked as the two roofs were of similar size, and having the roof roll over the top of the warm roof allowed for a smaller foot print than having the roof run off onto extending rails.

Above all I found it more fun to crack on with the build rather than try and plan everything out to the nth detail. My blueprint was in my head and often I could work out how to overcome any issue that was thrown up in the construction when it was in front of me rather than on paper. Sometimes when doing so you come up with a better way of doing something that way. - just have fun and enjoy your project. As Wayne often stated, you end up looking at the build with pride knowing that "I did that"

[laser_jock99]

Go as big as you can on the scope room. Mine is 3m x 3m for the simple reason that most of the construction material I was using came in 3m or 6m lengths and I didn't want to end up with a bunch of offcut waste. Making the thing in multiples of 1m had other benefits in terms of the sheet metal cladding, roofing sheets and flooring too. Very litle cutting involved exepcet for the internal tongue & groove wall cladding which was all 8 foot lengths!

[Digz]

Im sooo envious. I cant wait to be in a position to design and build my own obsy - or rather build it as I already have several designs knocking about.

[msh1]

im glad i built mine just wished id made it bigger 4x4 is a bit small should have gone for 6x6 but not a lot of room hey ho

[Astrokev]

To give a little more of an idea regarding what space I have to play with, here's an image of the intended site of the observatory. The existing shed is 10 feet long to give an idea of scale (following a recent move to make way for a house extension, this needs new felt laying on the roof, hence the disheveled appearance). The lengths of wood are just spare timber I happen to have lying around and are not intended for the obsy - not at the moment at least. The shed is due North, and I will be able to see the pole for alignment, which is good.

As you can see, the available space is reasonable, but unfortunately, the bushes on the other side of the fence in my neighbours driveway (West of the obsy) are pretty big and will block the view in that direction.

The panorama gives an idea of the view from North to South. East is definitely the best view with lowest horizon. The wide angle lens I used to take the panorama makes the garden look enormous! Unfotunately, the reality is that the house blocks views of the Southern horizon, but you have to make the best of what you've got!

Thanks for looking. Kev

[Astrokev]

hI Kev,

one of the things i did was to use the scope and mount and see what area i`d need around it before i divided up the area into warm room and scope room.

Thanks Rob. I think your right - trying to visualise sizes is very difficult. I hope to include a small warm room, so may follow your advice for determing how to carve up the space.

[Astrokev]

Good luck with your build also, Kev. ;-)

Thanks Chris. I'll race ya...

[Astrokev]

Kev,

I'm glad my build, along with others listed have inspired you to start your own project.

Above all I found it more fun to crack on with the build rather than try and plan everything out to the nth detail. My blueprint was in my head and often I could work out how to overcome any issue that was thrown up in the construction when it was in front of me rather than on paper. Sometimes when doing so you come up with a better way of doing something that way. - just have fun and enjoy your project. As Wayne often stated, you end up looking at the build with pride knowing that "I did that"

Thanks malc. If my obsy turns out half as good as yours, I'll be well chuffed.

I'm a bit of a planner I'm afraid, so while I agree with your design as you build approach, I'm not sure I can force myself to follow suit! I agree that things are bound to go awry and I'll have to plan on the hoof, but I'd like to start with a basic design at least. It also gives me a good excuse to play with SketchUp, which I love .

[Astrokev]

Im sooo envious. I cant wait to be in a position to design and build my own obsy - or rather build it as I already have several designs knocking about.

I suggest you withold your envy until I've actually built something Lee! Posting the start of a build thread ain't that difficult. But thanks anyway!

[Dave]

About time too matey.

I will look forward to having a visit over and seeing your progress first hand.

[Gina]

You definitely need to think very carefully and try mount/scope on tripod in various places before starting digging out for a pier base and foundations. And penty of planning is something I advocate as my ultra long design thread testimates Even so I was too keen to get on and started building my pier in the wrong place - I decided later. I'd got as far as digging a gert big hole and put rebar in and about a third filled with concrete! So I then had to cut the rebar off below ground level (not easy) and fill in the hole. Anyway, it was worth starting again with the pier as the second attempt has proved great

Good luck with you build Very hard work and teduious in places but also very rewarding - enjoy it

[Astrokev]

About time too matey.

I will look forward to having a visit over and seeing your progress first hand.

Thanks mate. You know you're always welcome anytime. Bring a shovel and a few cans though

[Astrokev]

You definitely need to think very carefully and try mount/scope on tripod in various places before starting digging out for a pier base and foundations. And penty of planning is something I advocate as my ultra long design thread testimates

Thanks Gina. Although I've got some scope to move the pier around, in practice I'm quite limited, as I don't want to encroach too much into the lawned area and, as I said in my opening post, the view West will always be hopeless, so not much to gain there. The only way of making much difference to the view South is by knocking the house down (my wife was not in favour of this option for some reason), or by building my obsy on the front garden (ditto). Sadly I don't have the wide expanses of the Devon countryside to play with!

I agree with you on the planning though. I'll be dusting off Sketchup soon to start playing with designs and dimensions. Can't wait! I'll be seeking guidance and views from those with build experience, such as yourself, along the way though....

[Digz]

Oooh, sketchup, you'll have fun with that. We use Autodesk Revit at work and one of my mates has modelled his mountain bike in it to see the effect of changing his set-up. I've yet to model my obsy design but might give it ago this week.

Cant wait to see your sketchup models.

[Gina]

I modelled my obsy build in Sketchup - very handy I've also used it to model my widefield rig mounting and other things. I like the way you can turn the model round and view it from all directions. I found the sectioning feature very useful too, particularly in designing how my roll off roof connected with the fixed parts. To be able to make parts invisible so that you can see inside is good too. As I recall, my obsy model had something like 30 parts/components. It took quite a long time to learn how to use Sketchup and to create all the componenst to scale.

[Astrokev]

I modelled my obsy build in Sketchup - very handy I've also used it to model my widefield rig mounting and other things. I like the way you can turn the model round and view it from all directions. I found the sectioning feature very useful too, particularly in designing how my roll off roof connected with the fixed parts. To be able to make parts invisible so that you can see inside is good too. As I recall, my obsy model had something like 30 parts/components. It took quite a long time to learn how to use Sketchup and to create all the componenst to scale.

I've been using SketchUp for a few years now, and am fairly familiar with most of it's functions. Most recently I constructed a scaled 3D rendition of my house to enable us to design our house extension. Trouble is, it can take over and easily becomes addictive!

I've generated some 2D drawings of my pier mount design and OTA to help me figure out obsy dimensions - I'll post these over the next few days.

[Astrokev]

As a starting point to deciding the size of my scope room, I thought it would be useful to draw my scope and mount in good old SketchUp, and design the observatory around it. So, here's what I've got. The mount is shown with the standard tripod.

Now, I've always thought a pier would be the way to go to mount the scope, as this obviously reduces trip hazards in the obsy. With this in mind, I managed to pick up a length of 280mm galvanised air duct tubing from my last company that was being thrown out, and this has been cluttering up my shed for the last 2 years (planning ahead there!). However, being quite wide, I've been wondering whether this would cause the OTA to crash into the pier. As you can see, I've overlaid the tube on top of the tripod and I now think it'll be fine, and may actually be better than the tripod. I've therefore decided to go with the tube and store the tripod - possibly to use as a portable mount.

So, next job is to design the observatory, decide how high I need to make the top of the pier, and to decide how to mount the NEQ onto the pier.

By the way, no idea who the bloke is standing next to the scope, but he's helping to give an idea of scale!

[Digz]

Nicely done. I assume you have positioned the scope in your sketchup model so it acheives balance, mwhahahah

[r3i]

Good to see that you're up and running with your project - wishing you all the best with the build and hope you enjoy it as much as I did doing mine. You'll have a great sense of achievement at the end.

[Astrokev]

Nicely done. I assume you have positioned the scope in your sketchup model so it acheives balance, mwhahahah

Haha, good question. You'll note there's no counterweight, so I should really have shown it toppling over into a crumpled heap!

[Astrokev]

Trying to decide how high to build the walls of the observatory is quite difficult. Ideally, I want to view as low down as possible, but this means either making the walls low, with the disadvantage of little protection from the wind, and also giving low headroom in the warm room, or having the pier and scope high, which makes it difficult to reach the eyepiece for visual work without a step ladder, and also gives problems with clearance for the rolling roof. To get good protection from the elements and stray light I'd like the walls as high as possible, but this would only give me access to the higher altitudes. The final solution therefore seems to be a compromise.

To help me decide I thought it would be useful to measure the altitude on the sky of my eastern horizon. Armed with this, I could then start playing with different configurations in Sketchup. So here's what I found with the aid of my Heath Robinson sky protractor. I calculated the angle by measuring the height of the perpendicular side of the triangle and a bit of trig'. The panorama is centred on East and shows the altitude of various obstructions. Overall, I think a target altitude of around 18-20 degrees will hopefully be OK.

[malc-c]

You could always build it with a drop down wall.