My 2.2m dome arrived today

[tomato]

Congratulations, it looks in better condition than my second hand dome, I’m just cleaning the sections after 18 months in storage, hopefully looking to assemble next weekend if we get some dry weather in between.

just a note of caution to anyone thinking of hiring a van to pick up a 2.2 m dome or move one any distance. Don’t go for a medium wheelbase VW Transporter, you will need two trips!

[JOC]

Good luck with it - how exciting.

[DAVE AMENDALL]

I can see that's going to be a great observatory once assembled. It seems to be a later model and much improved. This will probably be the best piece of kit you will buy and you will love it. My 2.2 metre obsy is a different make but I have no regrets purchasing it and would hate to be without it . It has been operational for three years now...Dave

Edited October 1, 2019 by DAVE AMENDALL
typo error

[tooth_dr]

12 hours ago, DAVE AMENDALL said:

I can see that's going to be a great observatory once assembled. It seems to be a later model and much improved. This will probably be the best piece of kit you will buy and you will love it. My 2.2 metre obsy is a different make but I have no regrets purchasing it and would hate to be without it . It has been operational for three years now...Dave

Thanks Dave.  It's about 4 years old, and came with all the gubbings I wanted.  I hope it will be a significant improvement over my ROR shed (which is being recycled into a playhouse for my kids)

[DAVE AMENDALL]

Possibly the main benefits you will experience apart from permanent set up is freedom from stray light and wind. I gave my ROR to a friend when I got my dome. I would love to see some pics posted when you have assembled it and up and running.  May it give you many happy hours...............Dave

[tooth_dr]

1 minute ago, DAVE AMENDALL said:

Possibly the main benefits you will experience apart from permanent set up is freedom from stray light and wind. I gave my ROR to a friend when I got my dome. I would love to see some pics posted when you have assembled it and up and running.  May it give you many happy hours...............Dave

Cheers Dave!  The wind protection is the main one for me.

[WanderingEye]

Looks superb.

its my dream to get a proper obsy one day..., but after reading many threads on here and other groups and forums, I settles on a ROR shed, but prefer the protection of a dome, but I read that they can suffer badly with condensation inside...not sure if this is correct, (assume it is as people would have no reason for untruths) but if so why does this happen with domes...??

[steppenwolf]

44 minutes ago, WanderingEye said:

but I read that they can suffer badly with condensation inside...not sure if this is correct, (assume it is as people would have no reason for untruths) but if so why does this happen with domes...??

It's not the domes per se, it is the fact that they have thin uninsulated glass fibre skins. I run a desiccant de-humidifier in mine to completely alleviate the problem.

[tooth_dr]

34 minutes ago, steppenwolf said:

It's not the domes per se, it is the fact that they have thin uninsulated glass fibre skins. I run a desiccant de-humidifier in mine to completely alleviate the problem.

This one has insulation fitted inside the dome, I believe to alleviate the dripping. I will be running a dehumidifier but I am debating whether or not to remove the insulation. 

[JOC]

We have issues with condensation from the corrugated iron on our animal housing.  We often solve it by adding in a secondary layer of bubble wrap plastic on to the underside of the battens that the roof sits on.  A bit like double glazing.

[DAVE AMENDALL]

The answer to condensation on the dome interior is a coat of rubberised bitumen paint.( I have no idea where to get this?) My dome came from the manufacturer treated this way in a flat black finish. it seem to be directly applied to the rough matt side of the fibreglass by brush. I never have condensation on the inside of the dome.However, I have condensation on the NEQ6 and on the pier I run an electric dehumidifier for about an hour which usually cures it... Dave

Edited October 2, 2019 by DAVE AMENDALL
typo

[JOC]

On 02/10/2019 at 15:06, DAVE AMENDALL said:

rubberised bitumen paint.( I have no idea where to get this?)

You used to be able to get it in 25 gallon drums from smallholding suppliers - it's often used on iron roofs and walls.

[GCG-Observatory]

On 30/09/2019 at 15:19, tooth_dr said:

It attived today

 

How did you get on with installing it? I am about to pick up a second hand Pulsar dome myself, same model as yours. Anymore tips or pointers for me to look out for? Did you put it on a concrete base?

 

[tooth_dr]

24 minutes ago, GCG-Observatory said:

How did you get on with installing it? I am about to pick up a second hand Pulsar dome myself, same model as yours. Anymore tips or pointers for me to look out for? Did you put it on a concrete base?

 

2 months later it is still sitting in the same place.  I cant believe it's two months since I got it!  The weather and dark nights have halted any work, so I've just put it on hold until Spring.  I seen your thread, and will be following it to.

[GCG-Observatory]

1 minute ago, tooth_dr said:

2 months later it is still sitting in the same place.  I cant believe it's two months since I got it!  The weather and dark nights have halted any work, so I've just put it on hold until Spring.  I seen your thread, and will be following it to.

lol, well I may be in the same boat haha, I am not sure that the guy I am buying it off has removed all the old silicone, so I may have to do that before I can install... need to probably find some way of easily removing it, possibly some product that will clean it all off/loosen it. Yeah the weather is a challenge this time of year. I am hoping I can get a mini digger in to dig out the pier base hole, and level the ground ready for concrete soon. Can't do it by hand as my ground is like concrete, as it's mostly shale. Should be fun though.

 

[DAVE AMENDALL]

I like the reference to concrete base. I made the sad mistake of erecting mine on decking. Although there has been no rotting for five years now. It requires constant  attention  including wood preservative by brush and filler to keep our lousy damp climate out.  Dave

[GCG-Observatory]

2 minutes ago, DAVE AMENDALL said:

I like the reference to concrete base. I made the sad mistake of erecting mine on decking. Although there has been no rotting for five years now. It requires constant  attention  including wood preservative by brush and filler to keep our lousy damp climate out.  Dave

Yeah I did consider that, but where I am in Wales it is so wet, and I know with sheds and wooden furniture etc I have had here, that they require constant maintenance, and eventually rot out. As to the concrete base, I am thinking that circular as close to the circumference of the pulsar dome would be best, as I see a lot of people do square bases, but surely that must increase the chances of water ingress under the dome walls, due to water pooling? Creating circular shuttering will likely prove an interesting challenge though.

[Benjam]

4 minutes ago, GCG-Observatory said:

Yeah I did consider that, but where I am in Wales it is so wet, and I know with sheds and wooden furniture etc I have had here, that they require constant maintenance, and eventually rot out. As to the concrete base, I am thinking that circular as close to the circumference of the pulsar dome would be best, as I see a lot of people do square bases, but surely that must increase the chances of water ingress under the dome walls, due to water pooling? Creating circular shuttering will likely prove an interesting challenge though.

I recently did a circular concrete base. Here’s my thread, I hope it helps you. 

 

[tooth_dr]

7 minutes ago, GCG-Observatory said:

Yeah I did consider that, but where I am in Wales it is so wet, and I know with sheds and wooden furniture etc I have had here, that they require constant maintenance, and eventually rot out. As to the concrete base, I am thinking that circular as close to the circumference of the pulsar dome would be best, as I see a lot of people do square bases, but surely that must increase the chances of water ingress under the dome walls, due to water pooling? Creating circular shuttering will likely prove an interesting challenge though.

I am making a circular base too. I was thinking not to go too close to the circular diameter of the dome to allow some meat for the bolts into the floor. 

[GCG-Observatory]

1 minute ago, tooth_dr said:

I am making a circular base too. I was thinking not to go too close to the circular diameter of the dome to allow some meat for the bolts into the floor. 

Good point - I was thinking of leaving about 1-2 inches overlap all round outside the walls.

[GCG-Observatory]

Picked up my dome yesterday from a lively chap in Farnham, easily fitted with room for another dome in a Luton box van. Packed the observatory by placing the wall section that contained a pod at the back of the van with the flat of the pod section against the wall of the van behind cab. Placed the other 3 parts of the walls inside the curve of the first, using pipe lagging as spacers to prevent the pieces rubbing together and scratching/breaking. Once all four pieces in place, put the dome shutter section also within the curve of the wall sections  and then ratchet strapped across the front and then wrapped another ratchet strap over all of the sections in the middle going around the top and bottom of the sections.

We finally placed the dome pieces carefully in front of the wall sections with the flat of the dome parts against one wall of the van, and the other flat part against our stacked wall sections, so ensuring they could be safely wedged for transportation . Again all 4 parts were fitted over each other, but separated with padding to prevent any damage. Ratchet strapped across the front of the dome parts. Everything was tightly packed and wasn’t going anywhere.
 

4 hours drive later we opened the back of the van and everything was as we had packed it, unloaded it onto the grass quickly to get the van back to the hire company just in time. Our back garden now looks like a UFO has crashed in it  

I will probably start a new post on this and update now going forward with my progress for anyone interested.

 

[pmlogg]

Concerning bases and decking, I bolted mine down onto a sandstone circle just a few inches bigger in diameter than the dome. It was laid after a central cube of concrete was poured for the pier attachment and the cabling trench completed. I just left out the central circular stone. The theory was that if we move I 'just' need to cut the bolts for the pier, remove or seal up the wiring and install the circular stone - to  produce a circular patio. 

I have decking but inside the dome, producing a floor raised above any ingress of water and allowing cables to be laid under a hinged decking board. The cables connect a desk at the wall with cables that come into the dome at the centre, by the pier.  After quite a few years the internal decking has only needed to be brushed off.  I like it as it feels much warmer than concrete and I suspect warmer than rubber tiles too.

[tooth_dr]

7 hours ago, pmlogg said:

Concerning bases and decking, I bolted mine down onto a sandstone circle just a few inches bigger in diameter than the dome. It was laid after a central cube of concrete was poured for the pier attachment and the cabling trench completed. I just left out the central circular stone. The theory was that if we move I 'just' need to cut the bolts for the pier, remove or seal up the wiring and install the circular stone - to  produce a circular patio. 

I have decking but inside the dome, producing a floor raised above any ingress of water and allowing cables to be laid under a hinged decking board. The cables connect a desk at the wall with cables that come into the dome at the centre, by the pier.  After quite a few years the internal decking has only needed to be brushed off.  I like it as it feels much warmer than concrete and I suspect warmer than rubber tiles too.

That sounds really good. Any photos?

[pmlogg]

Sorry for the delay in replying but been under the weather for a couple of days. 

My pier is metal, made by a local welder from pipe then powder coated.  The pier support is poured concrete using measurements from a Sky-at-Night article on DIY domes.

Not being very good at just doing carpentry on the hoof I used a spreadsheet to work out the decking panel lengths and "2x4" supporting framework and I did a diagram with the parts numbered.  My dome is the 2.7m version so the measurements will be different. I did the wood cutting and preparation during a good spell of weather in the late spring, before the dome arrived.  I used end-grain preservative on all of the end-cuts as well as the screw and cabling holes and used normal decking preservative for the flooring.  I numbered the support sections as per my diagram, having it in mind that it might someday have to be re-assembled elsewhere.

Once the dome arrived and was put together I assembled the floor inside, using screws.  I did have to make some adjustments, including slots to accommodate the flanges between each of the four dome wall sections, and a bit at the door - but overall I was pleased by the fit.  The cable access decking board has a hinge at the pier end and another in the middle. It's well supported by the sub-structure so is as stable as the rest of the floor. The pier is boxed in, for fitment of power boxes etc., with weather-proofed plywood but with access holes for cabling.  It doesn't touch the pier, to avoid vibration. I made a hexagonal plywood table top which goes around the pier at the top, on which I can rest bits and pieces - the only problem I did have later was potential contact at high elevations (I'd  bought a longer telescope). So I extended the pier by 30cm. 

The 'desk' top at the pier wall was a thing I bought to use when sitting on a couch with a laptop, painted black. I sandwiched the wall flange nearest the door with vertical 2x4 and then attached plywood to it for more cabling/power boxes and lights (one red, one white).  I used scraps from the decking panels as supports for the desktop itself.  Originally I used a small self-standing screen which sat on the desk but that's been replaced by a larger screen on a hinged wall mount, attached to more wood sandwiching that same flange but above the desk.  A desk light attaches to that too.  Again I did an excessive number of drawings too plan out the pier surround and desk but both have worked without need for modification.

The only down side with the floor is that there is a potential to lose small items between the floor boards (I left narrow gaps for ventilation).  Having learned that lesson I have a thin rubber-bottomed floor matt that I can put underneath when working with anything small enough to be lost.

 I have images on my home computer.  I will find them this evening.

 

[pmlogg]

Here are three photos and the diagram of the underfloor supports.  You can just make out the hinge close to the pier in one of the interior images and the cut for the other hinge (hidden below the floor) in the other image further along the same board, just at the bottom of the frame.

When I looked back at my notes I see that after cutting the flooring boards to length I laid them out on our patio and used a long piece of string secured in the centre and marked out the curved cuts at the outer edges of the boards.

For the cabling the power is an armoured cable; the electronics through drain pipe.   The cabling runs from the house (my warm room is under the stairs) to the pier under the 3m stone circle and then from there under the floor to the desk area.