Gina

getting there. Both of you .. ;-)

True, but seems slow at times! Still... better slow than rushing ahead too fast and tripping up.

One small mile stone achieved today (in between horrendous down pours of rain), is that the observatory computer is now on the network with full internet access. So when it's all up and running, the software is driving the scope taking all the subs automatically, I can sit back with a cuppa and keep up with things on SGL

Great That's where I'll be .... one day!

I'm always a bit wary of companies with the word "scam" in their name...

Well spotted

The thing is, most burglaies are opportunistic. Very few are pre-planned and I doubt if one in 10,000 would be as a result of what the thief finds on the internet.

Most thieves are age 16-24. They're not very bright. If they use "computer s***" at all, it's probably only to look at youtube or maybe facebook or less wholesome sites. They won't be surfing astronomy sites - and I am firmly convinced that the people who DO visit astronomy sites would never try to break into my house.

So while it probably IS worthwhile having your postcode somewhere on your equipment, so it can be returned if the police find it (and having photos of your kit to give the cops if the worst happens), I reckon that being a victim because of publishing your address is very, very unlikely.

The key is to prevent the most likely things that would make you a target. So, as long as your place appears more difficult to steal from than the house next door, you've probably done all you can to keep it secure.

Yes, I agree with all that. And having the place look like a tip is likely to make would be burglars think there's nothing worth pinching! Well that's my excuse!! :evil6:

I'm already planning to use my warm room as a little workshop. I've filled the bungalow, now I'm expanding into the garden

You can get really tiny CCTV cameras these days that can be easily hidden.

Definitely the Deluxe Version!

Oh yes

Yes, they're what I've got

Gina, I was the same... whilst we may have six or eight hours of darkness, it always seems an annoyance that you loose time setting it up and breaking kit down... trust me having the ability to unlock a door, roll the roof back and then power up a PC and start observing is something that we will both enjoy.

Yes, I'm looking forward to it I'm also planning to use the warm room as a workshop instead of the living room table!

I'm just wondering what your thread post count will be when you finally cut the ribbon on your observatory's official opening day

Yes, I'm wondering that too

In fact, having just got my scope I wasn't sure if this was going to be another one of those flash in the pan hobbies where it ends up gathering dust in the corner.

Same with me. Bought a cheap scope to see how much interest it would give. A fuzzy little image of Saturn with its rings, some reasonable moon pics and sun spots, encouraged me to spend an exorbitant amount of a posh mount. Also all the enthusiasm and encouragement from members here helped immensely

I found carting gear outdoors, setting it all up and getting frozen even before I started, followed by bringing it all indoors afterwards, rather a pain and a bit discouraging. Crawling around on the ground with one eye to an awkwardly placed polar scope was far from ideal!! So I decided I wanted an observatory. I think if I knew what I know now I might not have started. It's an immense project though very interesting. Or at least I might not have been so ambitious - but that's me, I go over the top It's the biggest project I've ever tackled! But I'm not giving up!

Yes, it's my information that adequate ventilation is most important.

Nice scope!

As you probably know, Darren, I have based my obs on your design (thanks again). About the steel angle brackets that strengthen the roll off structure :- did you make these yourself or buy them? If you bought them, where from? I have searched for such brackets on the net without success. They seem the best way to strengthen this section. Thanks

The steel option is fine if you have access to the raw material and can weld/cut etc. or have a tame steel fabricator on hand. OR can afford one of the ready made steel piers.

Yes, I'm thinking about windows too.

Very posh!

Anyone got any views on placement of the pipe, should it be recessed into the hole or be at ground level just to form the column part of the pier ?

Yes, referring to the diagram below, the left hand one shows the tube driven into the bottom of the hole. This is bad because there is no concrete connection between pier and base. The base block would do very little to stabilise the pier.

The second, middle, example shows the pier tube part way into the concrete base. This is a bit better but provides a weak point at the bottom of the tube.

Third, right hand, example shows the tube either level or just above the base top. This reduces any weak point and makes best use of the base weight. Further improvement is shown in some reinforcement bars driven into the ground below the base and extending up the pier. You will need to support the tube and provide shuttering to stop the concrete escaping from the pier bottom. Also, it's recommended that all the concrete is poured in one go ie. not allowed to harden part way through.

I have gone a bit further and made the bottom part of the pier wider using a couple of large plant pots with bottoms cut out. Also, the threaded rod used to hold the pier adapter goes way down the inside of the tube and provides further reinforcement.

Hi Gina,

The reason i ask about the diameter is because some boffin placed a post about pier construction and the diameter of the pier vs Angular deflection.

Obviously for imaging i want something super sturdy.

Pier Design: Diameter is your Friend!

The equation for angular pier deflection (given in the appendix) yields a very important relationship regarding the diameter of the pier. The angular deflection is proportional to the inverse (one-over) forth power of the diameter, that is, 1/(D^4). Let's put that into practical table of numbers.

Below we consider a pier that is 6 inches in OD. This purely imaginary pier is constructed of material like PVC pipe - it is not the steel which I recommend. Let's assume that it deflects 10 arc seconds for our 5 pound push - not a very good pier! What happens if we increase the diameter of the steel pipe while maintaining nearly constant wall thickness?

Diameter / Deflection arc seconds

6 / 10.0

8 / 3.2

10 / 1.3

12 / 0.6

I've read this article (if it's the one I think it is) and it applies to tubular steel piers only - concrete was not considered. Obviously a concrete pier will also be stronger/stiffer the wider it is but I've no idea how it compares with steel. Of course, concrete is totally different from steel and it is also extremely variable, depending on the ratios of ingredients and their quality. So I imagine a concrete pier would be virtually impossible to rate theoretically. I guess it's a case of build it and hope! Though users' experiences may still be of benefit.

Well, I'm hoping 7" diameter for a concrete pier will be enough for imaging - it's what I'm planning to do. Though there is still time for me to find something a bit bigger. The weather is holding things up ATM

Just to add... I made up my own pier adapter from a few pieces of plate and simple tools.

Pleased to hear it Gina, though you probably don't need to decide the final colour just yet!

No, not yet

Coming along nicely Malcolm I shan't be painting mine black either. Light green sounds nice.

Very good Malcolm

You should move to Bedfordshire. We're suffering a drought over here but, sadly, enjoying lots of cloud to go with it. Saying that, it's sunny at the moment....but then the sun hasn't set yet!

It's probably going to be clear tonight now that the lunar eclipse is over!

It's the heavy rain that's stopping me - apart from lack of funds. My site is waterlogged I might have to provide ground drainage.