Obsy pier equipment

[Jat999]

Hi all

I am going to start the build of my first observatory. I have decided to go with ShedsShedsSheds, having been over to see the guy who builds them.
The obsy will be on part of my vegatable plot, it will be a 12 x 8 with a roll-off roof. 
Firstly I need to build the pier.  As the plot has been cultivated, so I am thinking at least a 600 x 600 x 600 pier foundation with rebars driven down at least 1,200mm. 

At the moment, I don't know what height to build the pier to, so my thoughts are to fit the ducting, again with rebar and pour concrete to about a meter and leave the rest of the pour until the observatory is in place and I then know my working heights where I can cut the ducting and rebar to suit.

A couple of questions please?

1. Where can I buy the ducting from? I have rung a couple of H&V firms locally but they don't stock any.
2. I have an HEQ 5 mount. I see many people use brake discs as the mount adaptors. Am I right that the Renault Clio brakes with 61mm center hole is suitable? If not what have others used?

Thanks in advance
John

 

[Budgie1]

When I built my obsy, I use 200mm dia x 1.5m long plastic ducting as the outer casing and filled it with concrete and re-bar. The base was 700mm square with the ducting sat on some bricks in the bottom of the hold, so the base & the pier would be one sold concrete structure. 

My build is in this thread:

The pier I copied is in this thread:

This is the ducting I used: 8" Plastic Duct Round Solid Ducting Tube Pipe Ventilation Extractor Fan

I think these are the discs I used for the pier head, best measure the diameter of the HEQ5 base, but these discs have a 60mm hole in the centre: VAUXHALL CORSA B Front 93 to 00 236mm Set Bosch

Good luck with the build and keep us posted with the progress.

[Owmuchonomy]

Wow 12x8, that's a large roof to roll off.  Hope you've got a strong frame to accept it.  I also did 700x700x700.  Like you, I poured it then poured the extra block after playing with the kit.  I ended up adding another 150 mm to get the desired height.

[Carbon Brush]

If you want to go down the galvanised steel ventilation duct, you need to ask the right question.
Do you manufacture spiral duct?
Most ducting manufacturers have machinery for making rectangular duct, not circular.
Circular duct is made from a steel strip with rolled edges - in a spiral.

If you look at the ducting company web site, they may show sprial duct in their client example pages, or may list it in their capabilities.
Having found a company, just turn up at the workshop (not front) door carrying folding money, or beer, or similar currency.
These companies are not interested in making one short piece of duct. They are dealing with much bigger jobs.
If they make spiral duct for sale to other installers, it tends to be in long pieces like 5 metres
They may have an offcut on the way to the scrap skip, or they may be kind and make one for you during the tea break.

HTH, David.

[Jat999]

Hi all

Obsy arriving this weekend from ShedShedsSheds. Ordered a 10x6 with a 6x6 observation area and the 4x6 will basically be storage. I have prepared with power and Cat6 cabling as I will run the unit from the comfort of the house.
I have preliminary prepared the pier. I acquired 3mtrs of 200mm dia ducting. I have set the ducting into the ground. Originally I planned to site the obsy down the garden on the veg plot, however this was going to be a lot more work as I would need to significantly re align the veg plot adding more costs etc, so wife agreed to it now going on the patio. This was a good option as I laid the patio 25 years back and it is solid as it hid a lot of rubble under type 1 and block paving. I took out a 750mm x 750mm section, dug down below the old foundations by 500mm and set the ducting from there. Drove in 4 lengths of 12mm rebar and concreted up to ground level for now.
The obsy will sit on 5 lengths of railway sleepers. When they construct the obsy, they will cut a hole for the pier. Once built, I can then calculate the final height  of the pier.

One question I have for existing obsy owners please?

Regarding the control equipment for the scope. Currently I have a Milie PC and a Pegasus power box mounted on the image train. Am I better off to mount those on the side of the pier and then run the USB and power cables to the scope or keep them on the scope. I currently have a refractor, but I would also like to purchase a reflector in the near future?

[fifeskies]

Now you have a permanent home for your scope and are not setting up each night, if you intend to use more than 1 scope then it makes it easier to swap over systems if you mount the control equipment off the OTA.

The other advantage is that the reduction in weight should improve tracking.

 

Downside is that a little more care needs to be taken over cable management.

 

(There is an advantage of having everything on the OTA if you are having to cart it outside and place it on a mount and tripod each time.)

[Starflyer]

I have everything mounted on a perspex board with screw holes located so I can move it between my newt and frac as needed.

I have one USB and one power cable going through the mount, excuse the messy cabling but I was traveling

 

[M40]

19 hours ago, Jat999 said:

Regarding the control equipment for the scope. Currently I have a Milie PC and a Pegasus power box mounted on the image train. Am I better off to mount those on the side of the pier and then run the USB and power cables to the scope or keep them on the scope. I currently have a refractor, but I would also like to purchase a reflector in the near future?

I dont have an observatory but I do have a small pillar box type enclosure for the permanent pier. I have a power distribution box and a bracket for an asiair permanently mounted on the pier. I then have the power supply mounted in an enclosure about 2 meters from the pier and linked to the power distribution box. I then simply fit the asiair and plug cables into the power box and asiair. The cables are all the typical 2 meter type and to date all has worked well with no clashes between ota and stuff mounted on the pier. I frequenty swap telescopes so not having kit mounted on the ota works for me. If you choose to mount your kit on the pier, fit your ota to the mount and swing it around to make sure that when you mount your stuff, you have no clashes and the cable length is all good. All the best.