Observatory Questions..

[Greg]

Decided to bite the bullet and design and build the "Phatt" Obsy. before I get out the spade I have a few questions..

Pier..

Is it best to sink a 6" diameter metal pipe (Filled with concrete) Into the plug or bolt the 6" concrete filled metal tube to the plug..?? I have access to welding equipment if required and would there be much difference in stability..?

I have decided on either a 8'x6' or 10'x6' OSB Pent shed as the roof seems the easiest to adapt to a RoRo system..

Is it best to have the pier offset or dead centre of the obsy..?

Thanks

Greg

[Kai]

Is it best to sink a 6" diameter metal pipe (Filled with concrete) Into the plug or bolt the 6" concrete filled metal tube to the plug..?? I have access to welding equipment if required and would there be much difference in stability..?

I think the descision depends on if you are planning on moving.If you bolt it down then at least you can take it with you , if its in the ground it might be a bit tricky.

6 inches......If you can then i would go larger ie 8-10 inches as it will give you scope later on when you upgrade your mount (eg Eq6 or AP 1200 )

[CELESCOPE]

A lot of different opinions here Greg , like Steve says i would bolt, then it can be removed very easily , also the larger Obs ,u could build into that a small warm room ,keeping movement down , but to be honest ,my pier is bolted in my dome on an 8 inch concret slab , i can jump up and down all 17 stone and no wobble on my downloaded images , you can go over the top on these things . my gear runs on a 6 inch square tubing filled with sand , this is up to u as to what size you want , the bigger the better i guess , but my EQ6 PRO is just fine .

Rog

[Parallax]

This may (or may not) help but, what I did was downloaded Google Sketchup, which is a free 3D drawing program. I modelled the shed plus warm room, then modelled the tripod/mount/scope and 'placed' it into the shed. I was then able to rotate the scope in its' RA and DEC to see how much of the sky I would be able to see. After a bit of trial and error I found the optimum position for the tripod.

Google Sketchup is fairly easy to get the hang of (although that's a bit subjective!).

HTH

Steve

p.s. the models were fairly basic.

[Kai]

Decided to bite the bullet and design and build the "Phatt" Obsy. before I get out the spade I have a few questions..

As long as you supply the beers and nibbles give me a shout and i will come and help

[Greg]

Another question..

Is a 10'x6' shed/obsy big enough would you think??

[Helen]

If you've got room go a bit bigger Greg. Mine is 11x8 (exterior) and that allows for a 3 foot warm/storage room, and still 7.5+ foot square interior scope area. I've got a wedge and there is enough room to comfortable move around and still leave the corners for little shelves (for the tea mug etc) and for storing tripods. If you've got an EQ more space might be needed. Someone suggested getting a few bits of tarp or similar and just setting it up in the garden with your scope to give you a feel for size. It'll also allow you to try different placements for the pier. In my case I positioned mine to take account of where I wanted to look most, and where my horizons were best - remembering that closer to a shed wall means knocking out more low-down sky.

Helen

[Robd]

Greg,

I would go bigger if you can. The turrets on my Obs. are on a 2m dia ring. This leaves approx 6ft ( note the swift change of dimensions there ) inside the turret.

This is just about OK for the LX200 but a bit on the tight side for the 6" refractor on the EQ at the business end.

Rob

[saturn5]

I dont really see the need to go as large as 8-10 inch pipe.

I have my HEQ5 on a 4.5 inch diameter heavy wall aluminium pipe(filled with sand) sunk in a 2ft cubed hole and it doesnt move one bit so i would say 6 inch will be more than sufficient,even for an EQ6

I agree with Rog that "you can go over the top on these things".

Good luck with the obsy.