My 2.2m dome arrived today

[tooth_dr]

No response to my original question.  Try again!

Im at the planning stage of a 2.2m dome.

Concrete base - how many ducts need to run inside the concrete - is two enough?.  Does anyone have a false raised floor inside for cable management?  How do you get the cables from the floor to the pier base, if the pier base is separate - does anyone run the ducts through both? 

Pier - what’s the optimal height for the pier, if I’m currently using an EQ6, intending to likely change this in the future to a Mesu 200.

Im sure I’ll have more questions as I don’t want to mess this up!  I’ve built two ROR sheds so far but they are a bit more forgiving for retrofitting things and also more spacious.

 

Thanks for your patience!

 

Regards

Adam

 

Edited September 30, 2019 by tooth_dr

[tooth_dr]

Im planning on getting one bay, or do I need it?

[michael8554]

With my Pulsar 2.1

I ran two conduits from the warm room to the dome.

I tee'd off just inside the perimeter so that I could mount some power points and a monitor on the wall.

These two conduits continued underground as close as I could get to the pier without spoiling the isolation.

They came up and out of the concrete base about 6 inches.

Then the cables ran up the pier from loops out of the conduit.

I used solvent weld pipe with slow bends.

50mm was fine for the Mains, but over time the other 50mm for data cables got rather full, so bigger would be good.

Pier height ? Depends how high your dome wall is !

Pier might need to be offset from centre so your scope can point to the zenith, especially the guidescope if mounted on top.

Michael

 

[tooth_dr]

33 minutes ago, michael8554 said:

With my Pulsar 2.1

I ran two conduits from the warm room to the dome.

I tee'd off just inside the perimeter so that I could mount some power points and a monitor on the wall.

These two conduits continued underground as close as I could get to the pier without spoiling the isolation.

They came up and out of the concrete base about 6 inches.

Then the cables ran up the pier from loops out of the conduit.

I used solvent weld pipe with slow bends.

50mm was fine for the Mains, but over time the other 50mm for data cables got rather full, so bigger would be good.

Pier height ? Depends how high your dome wall is !

Pier might need to be offset from centre so your scope can point to the zenith, especially the guidescope if mounted on top.

Michael

 

Thank so much Michael.  I was wondering about off setting the pier, in my ROR shed the pier is the middle, and my largest scope collided with the wall on one side. If offset this wouldn’t have been an issue.

Im not sure what the standard wall height is for the domes, I’ll check that.

I have 12 x 240v items plugged into sockets in my shed observatory.  I will need to factor in socket placement etc. Heat from the 3 x PCs might an issue if in the dome with the scope. Currently they are in my warm room and north of the scope. 

[Hallingskies]

On 04/09/2019 at 12:07, tooth_dr said:

No response to my original question.  Try again!

Im at the planning stage of a 2.2m dome.

Concrete base - how many ducts need to run inside the concrete - is two enough?.  Does anyone have a false raised floor inside for cable management?  How do you get the cables from the floor to the pier base, if the pier base is separate - does anyone run the ducts through both? 

Pier - what’s the optimal height for the pier, if I’m currently using an EQ6, intending to likely change this in the future to a Mesu 200.

Im sure I’ll have more questions as I don’t want to mess this up!  I’ve built two ROR sheds so far but they are a bit more forgiving for retrofitting things and also more spacious.

 

Thanks for your patience!

 

Regards

Adam

 

I have the 2.2m dome and would probably do things a bit differently were I doing it again.

Firstly I would have just gone for a dome-only build: I have accepted that the fibre glass body offers no security whatsoever.  I would use concrete blocks with an adjoining warm room a second time around.  I think there is a build thread on here along those lines and it looks superb.

I ran a single 1 inch conduit under the base concrete and fed the armoured feed power cable to a RCD box mounted on a board inside.  I used flexible ducts for lighting and power cables and stuck the duct bracket bases to the walls with fibre glass car body filler.  It kept things tidy.

I wish I had run a second duct for a data out cable as I now want to run some Cat 5 back to the house as an afterthought.

I don’t think there is really room for a raised floor.  I use a Pegasus hub on the scope and only have two cables to take back (data to the pc and 12v to the hub). I just put them through a standard floor cable shield stuck down with carpet tape.  Power sockets and wiring is all attached to the walls as described.

I have one of the additional cubby hole extensions and have put a pc desk in it for the lappy docking station with extra keyboard and mouse. Things would be cramped without it.

You will need a dehumidifier in there as the fibreglass structure is a condensation magnet.  Some folk say you can just use ventilation etc but I have found that just does not work.  I have wired my dehumidifier into a Stego humidistat set at 55%.  It comes on for about four minutes every half hour at absolute worst.  Sometimes it doesn’t run for days, obviously depends on weather.

I reduced the air gap between the dome and the body with 7mm p seal.  That cuts down the air ingress without hindering the dome rotation and I only have to empty the dehumidifier once or twice a week, even in winter.  I did have a plumbed in drain but that froze up.

My pier is 850mm high I think - I got it from Pulsar at the same time as the dome.  It’s just the right height for an NEQ6.

 

[tooth_dr]

10 minutes ago, Hallingskies said:

I have the 2.2m dome and would probably do things a bit differently were I doing it again.

Firstly I would have just gone for a dome-only build: I have accepted that the fibre glass body offers no security whatsoever.  I would use concrete blocks with an adjoining warm room a second time around.  I think there is a build thread on here along those lines and it looks superb.

I ran a single 1 inch conduit under the base concrete and fed the armoured feed power cable to a RCD box mounted on a board inside.  I used flexible ducts for lighting and power cables and stuck the duct bracket bases to the walls with fibre glass car body filler.  It kept things tidy.

I wish I had run a second duct for a data out cable as I now want to run some Cat 5 back to the house as an afterthought.

I don’t think there is really room for a raised floor.  I use a Pegasus hub on the scope and only have two cables to take back (data to the pc and 12v to the hub). I just put them through a standard floor cable shield stuck down with carpet tape.  Power sockets and wiring is all attached to the walls as described.

I have one of the additional cubby hole extensions and have put a pc desk in it for the lappy docking station with extra keyboard and mouse. Things would be cramped without it.

You will need a dehumidifier in there as the fibreglass structure is a condensation magnet.  Some folk say you can just use ventilation etc but I have found that just does not work.  I have wired my dehumidifier into a Stego humidistat set at 55%.  It comes on for about four minutes every half hour at absolute worst.  Sometimes it doesn’t run for days, obviously depends on weather.

I reduced the air gap between the dome and the body with 7mm p seal.  That cuts down the air ingress without hindering the dome rotation and I only have to empty the dehumidifier once or twice a week, even in winter.  I did have a plumbed in drain but that froze up.

My pier is 850mm high I think - I got it from Pulsar at the same time as the dome.  It’s just the right height for an NEQ6.

 

Thanks. Great info.

I haven’t ruled out building a brick structure and mounting a dome on it.  My concerns were a) attaching the dome and b) heat from the bricks.

If I built my own base it would certainly leave more options, as I’m used to a warm room. But it would also increase costs, the fibreglass walls are ‘only’ £900

[steppenwolf]

I have the same domed observatory and I have a couple of comments:-

1. You need more ducts

   AC Power
   CAT 5 Network cable
   'Security' link
   Drain pipe for de-humidifier
   CloudWatcher connection
   At least one spare (AllSky Camera etc.)

2. I don't have any bays but I would recommend getting one for your computer and monitor

3. I have a spreadsheet that may help you set up the slaving of the dome to the telescope when the time comes

[tooth_dr]

1 hour ago, steppenwolf said:

I have the same domed observatory and I have a couple of comments:-

1. You need more ducts

   AC Power
   CAT 5 Network cable
   'Security' link
   Drain pipe for de-humidifier
   CloudWatcher connection
   At least one spare (AllSky Camera etc.)

2. I don't have any bays but I would recommend getting one for your computer and monitor

3. I have a spreadsheet that may help you set up the slaving of the dome to the telescope when the time comes

Thanks Steve. I’ve read your thread and find it very informative, but got a bit lost with all the software stuff.  I’ll need to plan this out carefully. My wooden ROR shed is a lot more forgiving both in terms of space, and for retro fitting stuff (ie hidden under floor).

[steppenwolf]

If you do go down this route, I will be here with many others to help you through the set-up but, it is fair to say that it isn’ always straightforward!

[sloz1664]

Totally agree with all comments regarding full dome installation. With exceptions of:- Use Cat6 cable for future proofing, even optic cable if you can install it. Minimum three ducts with two spare "pulla wires" in each duct, in case you need to add any additional cables.

Steve

[tomato]

Hi Adam,

I have a thread running in the DIY Observatory section entitled ‘Deep Sky West (Midlands)’, lol, the build consists of a Pulsar 2.2 metre dome with adjacent warm room shed. It has a single 68mm ducting from the warm room to the dome with upright ducts at the dome wall and base centre. Everything in the dome will be powered by 12v supplied from the warm room, there will be a single 240v AC cable running through the duct alongside the power and data cables, but this will only be used to supply power in the dome when the imaging rig is not operating.

The dome and shutter will be powered and automated, but this will be a stand alone system on the dome only. The shed is up and the concrete poured for the pier base, it will have an Altair pier, not too fussed about the height as this will be for imaging only.

Steve

[tooth_dr]

Thanks guys. I’m excited about this. I’ll take time to read through and consider everything mentioned above. Thanks again. 

[Tomatobro]

Tomato's specification is somewhat influenced by my own observatory experience.

!2 volt supply comes from the fact that I once had a "tickle" from a wet extension lead and from that day on I have only ever had external power via a warm room located linear power supply. The is a secondary reason. I have noticed that when using my meteor detection kit the USB cable can pick up noise from the laptop power supply if the two are close together. This noise is seen as a increase in background noise level in the Spectrum Lab display. The linear power supply has Voltage and Current indicators and the patterns of Current usage gives one confidence of system integrity. There is a device on the scope which measures voltage at the mount end and signals back to the warm room the voltage. A monitor on the wall shows a graph of the voltage so I can see filter wheel changes etc are taking place. If say 4 amps is missing then I have forgot to switch the camera cooler on. The long supply cable from the warm room and induces a volt drop depending upon the load applied so that is why the voltage is remotely monitored.

It also gives you something to do while waiting for the pictures to download.......

 

[tooth_dr]

Just got a quote for delivery. More than I expected so may consider alternative arrangements for collection. 

Edited September 23, 2019 by tooth_dr

[tooth_dr]

So... things have progressed more rapidly than I could have anticipated 🥳

A 2.2m dome is due to be delivered this week.

Please be patient if i ask some stupid questions 😎

Edited September 23, 2019 by tooth_dr

[steppenwolf]

On 23/09/2019 at 23:03, tooth_dr said:

So... things have progressed more rapidly than I could have anticipated 🥳

A 2.2m dome is due to be delivered this week.

Ooooohh, how very exciting!!

[tooth_dr]

2 minutes ago, steppenwolf said:

Ooooohh, how very exciting!!

It attived today

 

[paul mc c]

Nice one....a proper obsy,maybe one day i will have one.

[steppenwolf]

28 minutes ago, tooth_dr said:

It attived today

Great news - you are in for a treat! A couple of pointers:-

1. Concentrate on getting the base of the dome and the top of the walls flat where each section butts up to the next as this will ensure smooth rotation.

2. Don't rely purely on the pre-drilled holes - file any out that impede 1. above - To be fair, my bolt holes were very well aligned straight from the factory

3. Spend plenty of time ensuring that the north-south diameter matches perfectly the east-west diameter on the walls before you bolt it down to the plinth.

[tooth_dr]

27 minutes ago, paul mc c said:

Nice one....a proper obsy,maybe one day i will have one.

Thanks Paul. I was very fortunate in that this one turned up for sale locally. 

[tooth_dr]

14 minutes ago, steppenwolf said:

Great news - you are in for a treat! A couple of pointers:-

1. Concentrate on getting the base of the dome and the top of the walls flat where each section butts up to the next as this will ensure smooth rotation.

2. Don't rely purely on the pre-drilled holes - file any out that impede 1. above - To be fair, my bolt holes were very well aligned straight from the factory

3. Spend plenty of time ensuring that the north-south diameter matches perfectly the east-west diameter on the walls before you bolt it down to the plinth.

Thanks Steve that’s excellent advice to prevent any distortion for the dome itself to move better.

Despite the appearance, it’s actually second hand. He cleaned it up, removing all traces of silicone etc. I just need to find out what would be the best silicone to seal it with now. 

Edited September 30, 2019 by tooth_dr

[Astro-Geek]

Well I've made a start (with my Avatar).........   

If anyone is searching for ideas on equipping a home observatory, there's always Google image searching, like this one:

https://www.google.com/search?q=diy+observatory&client=firefox-b-d&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiJndHb7_jkAhVgURUIHSVbA0MQ_AUIESgB&biw=1535&bih=768

I torture myself with it on quite a regular basis.....  😥

 

[upahill]

1 hour ago, tooth_dr said:

It attived today

 

Congrats, that looks so much more manageable in sections! The design has really improved I think.

Bet you can't wait to get in it

 

[tooth_dr]

4 minutes ago, upahill said:

Congrats, that looks so much more manageable in sections! The design has really improved I think.

Bet you can't wait to get in it

 

I am indeed!  I havent actually seen it yet either, so cant wait to get home from work.

[steppenwolf]

1 hour ago, tooth_dr said:

Despite the appearance, it’s actually second hand. He cleaned it up, removing all traces of silicone etc.

Well it looks in great condition and that explains the modification to the skirt on the dome section - I guess this is an additional drip rail?