Obsy Build Has Started!

[Budgie1]

I've been planning to build an obsy for about a year because it's just a pain (literally) dragging the mount, tripod, scope, laptop......... through the house to setup in the garden at the sniff of a clear night. I've been scrolling through this part of the forum seeing what others have done and settled on a ROR shed approach in the end. 

I first looked around for a shed which didn't look that hard to convert and came across a 6x8 Reverse Apex shed by Forest Garden, I would have liked to go with a tongue & groove built shed but that added too much money to the price, so this will do. Looking at the construction of the shed, the whole roof & pitched gable ends are separate from the walls, so this makes for an easy conversion (I hope). It also means I don't have an issue with the door being taller than the walls, like they are on most normal apex sheds.

So that was the shed sorted and delivered, next was the pier. For this I copied the method and materials used by @Domain105 in THIS THREAD, only I decided to use three 16mm threaded bars, instead of four, to connect the two discs and it seems to be fine for stability.

I started construction this week, marked out where the shed would be and orientated it so the rear of the shed was facing North. This means the pier is also facing towards the back wall but the orientation is mainly for the prevailing wind direction. We get a funnel effect with Southerly winds and this will hit the shed on the Southeast corner, meaning it will disperse either side of the shed and push the door & roof closed. It will also deflect the wind away from the greenhouse, which was blown down by 60 mph gusts about 3 years ago, just 2 days after I put it up!

I had five 4" fence posts already, so used these to construct the shed base and decided to pour concrete footings, one at each corner, to level the base. First I dug the hole for the pier and made it 700mm square. Into this I put five 1.2m lengths of rebar for the pier tube and stood the tube on top of a couple of bricks stood on their end to raise the tube. 

With the thickness of the base + the shed floor, I didn't want the pier to be too short and not be able to get the scope high enough to see over the shed walls. With the assistance of a neighbours' mixer, I poured the pier base earlier this week and completed the shed footings on Friday. The pier is very solid at this height and you may notice that one of the footings is sightly out of position. This was a miscalculation on my part but it's level with the others, which is what counts.

The shed base is now in position but not secured to the footings and I'm going to leave the concrete to go off before I start on the shed floor & walls. I still need to cut the hole in the floor for the pier and you'll see that I've placed the pier slightly to one end of the shed, just to give me more working room at the door end, where I intent to put the electrics and laptop etc.

So here's where we are at the moment and I'll keep this thread updated as I progress.

 

Edited July 17, 2022 by Budgie1

[Swoop1]

Another obsy build thread for me to follow!

I love obsy build threads😀

[Budgie1]

3 hours ago, Swoop1 said:

I love obsy build threads😀

And we love struggling through the process for you. 🤣

[pavel_s]

It looks like you put the wood directly onto the concrete? 

[Budgie1]

1 hour ago, pavel_s said:

It looks like you put the wood directly onto the concrete? 

It's not fixed down yet as the concrete is still drying but I'll put some damp course between them when I do fix it in place permanently.

[Budgie1]

Work got in the way of things this week and only a little progress has been made. I don't think much is going to happen over this weekend either as we're due 30-40mm of rain.

Anyway, I did managed to install some floor joists in the base, the base has been painted with a couple of coats of Cuprinol Ducksback and I've also installed damp course to the base.

I cut the hole in the floor for the pier this evening, remembering to make it large enough to go over the discs! Once the floor is in place then I'll make a collar from marine ply to go around the base of the pier and cover the gap.  

I've also got two 5mm thick, 150mm dia laser cut round plates for the pier. One has a 10mm hole in the centre for the mounting bolt to go through and the other is blank and will cover the recess in the bottom disc. I'll post photos of these once they're painted.

So here's the build as it is tonight:

[maw lod qan]

It looks like a good start. And don't worry about the footer pad being different from the others!

I believe it was the Shakers who always put a small flaw into their incredible carpentry work. 

They believed only one builder's creations were perfect. 

When I look into the sky's above me, I can believe that!

[Domain105]

Hi, looking good. Glad what I did to build my pier a while ago maybe helped you out. If you need any more info, let me know and I will be happy to help. 

Since my build, I have automated the roof opening and closing with a solar panel and roller chain. I'm now in the process of buidling an all sky camera to mount on my obsy. Was the best decision ever. you will not regret it. It makes such a big difference.

Goodluck and I hope all goes well 🙂

 

 

[Budgie1]

Thanks, it wasn't that harder build for the pier, especially as you listed all the parts you used! Because mine is a shed conversion, rather than a scratch build, I still have to fathom the bracing for the shed walls and the runners for the roof, most of all, the roof assembly itself. But I'll get the walls up first and see where we go from there.

I've made a bit more progress this week. Once the hole was cut for the pier I painted the flood sections with more Ducksback, both on the underside + runners and the floor. It may not have the roof on for a while, so I wanted protection for the floor in the meantime. As you can see below, both floor sections are now in position and screwed down to the base. I think it makes a nice observing platform as it is!

Next is the walls, starting from the rear corner and working forward. But that's for after work tomorrow.

[Budgie1]

Well, that's the walls in place and screwed together.

The piece over the door is only temporary to add rigidity to the structure until I can get the 4x2's cut to frame & strengthen the inside. I was going to make a start this evening but I went out there after tea and the great Clan MacMidge had descended on the proceedings and I hadn't Smidged up, so I called it a night and will start on the framing tomorrow.

[Budgie1]

Things are progressing.

Yesterday, while I was at work, my wife kindly sprayed the first coat of DucksBack on the walls of the shed and the roof sections. She just finished the roof panels when the rain started. Luckily she did the walls first, so they were already dry and the roof panels were put under cover for the night. 

Today, she gave the walls another two coats with the sprayer and when I got home I started into cutting the 4x2 to frame the inside.

I've used an upright in each corner to support the frame around the top of the walls. I cut a slot in the each front corner for the roof runners to sit in and they are temporarily supported at the front by the fence posts which are clamped to them. I still need to cut the runners to length, I don't intend for the roof to roll off that far!  

The frame is secured to the shed walls and it's rock solid now, although the front section of the frame does cover the top of the door opening and the top of the windows, but I can live with that to keep the walls at the height I want.

If the weather's okay on Saturday then I'll be looking to dig the footings for the front posts and get the cross braces cut and fixed.

 

[ArmyAirForce]

It's coming on really quickly and looks great.

[maw lod qan]

The siding looks very nice! I've always liked lap siding. The second floor of my house is lap siding!

Most of all I can't help but admire the area around the observatory.  Very beautiful. And the hills in the distance, oh yeah.

Florida is flat! Between me and the Gulf of Mexico 35 miles away the highest point ASL is about 50'.

[Budgie1]

2 hours ago, ArmyAirForce said:

It's coming on really quickly and looks great.

Thanks, I've been pushing to get the main structure completed by this weekend as I won't be able to do anything next week due to work commitments, so I wanted to get it up and supported with the framework.

2 hours ago, maw lod qan said:

The siding looks very nice! I've always liked lap siding. The second floor of my house is lap siding!

Most of all I can't help but admire the area around the observatory.  Very beautiful. And the hills in the distance, oh yeah.

Florida is flat! Between me and the Gulf of Mexico 35 miles away the highest point ASL is about 50'.

We are blessed with the scenery around here and it's also Bortle 2, so nice dark skies between late August & Early May. The hills are nice to look at and climb but, being on the West Coast of Scotland, we're landfall for most of the weather systems coming in from the Atlantic. And what happens to moist air when it hits hills & mountains? It rises and the water vapour  condenses, meaning it rains here... alot! This year it's rained on 154 days so far. I wouldn't live anywhere else though.

Anyway, back to the build.

Today was dodging showers and drizzle but my wife completed the paint spraying on the roof panels, so assembly and framing of the roof is next in the plan. But that'll have to wait a week.

I cut the roof runners to length and dug the footings for the support posts. These are now set in Postcrete and I replaced the turf around them, they just need cutting to height. The roof runners are screwed to the support posts and I've installed a cross beam and braces. Even before the Postcrete has gone off, the structure is now solid.

So, this is likely to be it for a week. In the meantime I still need to sort out what I'm going to use to roll the roof. I undecided as to whether to go with @ArmyAirForce approach and use aluminium angle and nylon/rubber wheels, or use gate track and steel wheels. Something to ponder over and order next week.

[ArmyAirForce]

8 hours ago, Budgie1 said:

.....whether to go with @ArmyAirForce approach and use aluminium angle and nylon/rubber wheels, or use gate track and steel wheels.....

I went for aluminium on my last obsy and on the new one because it won't rust and was easy to drill and countersink for the fitting screws.

[maw lod qan]

I also used 2"×2" aluminum angle on mine.

The roof frame is 2"×3" rectangular aluminum, very light. Rolls back with one hand.

[Budgie1]

So, as I said above, not much happened last week due to being away with work. I did manage to cut the supporting posts to length and ordered a couple of galvanised caps for them before I went (caps arriving this week).

Yesterday I didn't feel like doing much but did make the ring to go around the base of the pier to cover the hole, so I don't drop anything down there. It was made from a spare piece of Marine Ply, using a router to cut it out, painted yesterday and fitted this afternoon.

Today is a bit drizzly but I managed to get the 4x2 frame built for the roof section, which is sat on top of the walls at the moment. Rain has now stopped play.

I've ordered four x 2m lengths of aluminium unequal angle for the runners, a set of 50mm fixed casters and four heavy duty Toggle Clamps for securing the roof when it's closed. Hopefully these should all be here sometime this week. I need to get the runners installed and the wheels bolted to the frame so I can work out where the frame will sit inside the walls of the roof section, before I start putting the roof together.

Edited August 7, 2022 by Budgie1

[Budgie1]

I've been doing a few little bits in the evenings this week;

The galvanised caps arrived for the support posts, so they have been sprayed & fitted. Also the casters & toggle clamps have arrived but the aluminium seems to have spent the day at the Parcel Force Perth Depot, so it may get here this week.

I put my EQ5 mount on the pier for the first time yesterday evening, just to make sure it fitted and that I'd got the orientation correct for Polar Alignment. I had to do a bit of filing on the bolt head for the North Peg as it protruded into centre hole of top plate, but once that was sorted the mount slotted into place and Polaris was in the Polar Scope without having to move the mount at all.   I only used the EQ5 for this test fitting as it was lighter than my HEQ5, which will be living on the pier when the obsy is complete.  

I assembled the roof sections this afternoon, which will have to get lifted off so I can install the aluminium angle, but it gets me further on and I had to do the cut-out on the front section for the runners. I don't want to fit the roof boards as this will just add more weight to the roof when it comes to lifting it off.

Tomorrow the plan is to install the casters on the roof frame and secure the frame to the roof section, unless the aluminium arrives, in which case I'll get that on the runners first.

Edited August 11, 2022 by Budgie1

[ArmyAirForce]

Don't forget you may need a bit more clearance on the roof to runner gap as the timber gets more moist during the wetter months and expands.

[Budgie1]

Yes, I'd planned for that as we have 12 "wetter" months up here, check out blanket of cloud over the mountains in the background that this heatwave has given us today!  😂

This is a rough fitting at the moment. I still need to make the vertical slot for the runner and the whole roof will be lifted a few mm to clear the walls.

I also need to get some feather board to go around the gap between the roof section and the walls, to act as some weather proofing and I'm planning on hinging the rear feather board so can be lifted and locked in place to clear the rear wall as I roll the roof forwards.

[Skipper Billy]

15 minutes ago, Budgie1 said:

Yes, I'd planned for that as we have 12 "wetter" months up here, check out blanket of cloud over the mountains in the background that this heatwave has given us today!  😂

Ah summer in Scotland. It's probably my favourite day of the year 😉 

Well done - looking good!

[Budgie1]

47 minutes ago, Skipper Billy said:

Ah summer in Scotland. It's probably my favourite day of the year 😉 

Well done - looking good!

Yep, I heard it's "Taps Aff" for tomorrow, David, better get the Factor 80 out! 🤣

I've got a name for the Obsy;

Seeing as I spend most of my imaging sessions sharing the garden with them, while they eat the peanuts out the squirrel feeders, I thought I'd go for:

[Budgie1]

Well, the aluminium angle didn't turn up, so today I got the casters fitted to the roof frame and raised the roof about 10mm all round so I could secure the roof frame to it. Once the aluminium angle is in place, that will add another 3.2mm in height and will allow the roof to clear the walls so it will roll. 

[Budgie1]

I got home from work this afternoon to find the aluminium angle for the track had arrived!

It was raining a bit, but I got the track cut to length, drilled & countersunk the fixing holes and jacked the roof section up. After stopping for food, it was raining a bit harder and very midgy, so I Smidged up and got on with installing the tracks.

 

I then found I had a slight miscalculation and the roof section was still catching at the back and on the angle at the front. So, rather than fiddling with cut-outs and slots, I decided just to unscrew the roof frame and lift the roof section by another 15mm, then reattach the roof frame. This worked a treat and all I had to do was a couple of slots in the rear face for the angle uprights.

It needs a little tuning but I now have a Roll-off Roof! 

Roof boards and felt is next, when the rain stops!

[M40]

A great build and some fantastic views 👌 Quick question for you though, nothing whatsoever to do with obs, but we are staying near Aberfeldy in about a month or so's time, what do you use to "smidge up" as I do tend to be a mosquito magnet and I fully intend to get out weather permitting to enjoy the bortle 2.