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Base for Observatory

Posted: Sat Jun 27, 2020 6:08 pm
by OhNo
Well, a used SkyShed Pod came up for sale on Canada-wide Buy and Sell. I don't frequent that web site often, but something told me I ought to.... you know, the cousin of the little Devil sitting on one shoulder and the Angel on the other. I've been toying with the idea of a observatory since I got involved in the hobby. I was the first one to respond to this guys add wihin an hour of him posting it. 3 other people inquired in the next 5 hours.

He said he'd send me pics of it assembled and taken apart. Being seven years old I was concerned about deterioration. Being I could afford a new one like this, the shipping was a deal breaker on new. There are always incidental cost even after you figure you've got the final cost figured.... I told the guy that I'd come out the next day, not wanting to lose another one in my travel range. So off I go with the cargo trailer in tow. 550km one way, so I hoped I wasn't going to head home with an empty trailer. Sure enough it was in as good or better shape than he described.

On the initial phone conversation I did ask the all important question, "why are you getting rid of it". He hadn't lost interest in the hobby, he was expanding. Now he is 1/2 done a new ROR with 2 piers in it for AP!!!!

This all brings me to the question. What should I use as a base to anchor the thing. The previous owner was on a cement pad. My concern with this is cement acts like a big heat sink. With forward planning, opening up a hot building with a major heat sink will take planning for the acclimation. My concern it anchorage. We get som mighty wind here. The other issue with cement is we are 50 miles away from the closest supplier, and of coarse cost. Wood rots over time. !8x18x1 1/2 patio blocks could be an option, but concerns me with the anchoring issue.

Some would see my other issue as mute, but this thing is the three pod configuration. This all equals a big footprint. If it was just the pod, or even a pod with one bay, I'd mix and pour my own pad. Not gonna even consider home made cement with the amount I'd need for a whole pad.

What are other using under their home observatories?

Re: Base for Observatory

Posted: Sat Jun 27, 2020 6:26 pm
by Lady Fraktor
A concrete pad large enough to support a pier with low/ horizontal legs then build a raised wooden floor base over it with a hole for the pier to come through.
If the wood is varnished/ painted it should last many years before you would require major maintenance.

Re: Base for Observatory

Posted: Sat Jun 27, 2020 6:50 pm
by OhNo
Thanks Gabby, I considered that. My pier is coming up on it's second birthday, one of the best things I've done for myself. No polar alignment every night.... That said, it isn't real tall. I've learned my lessons about imaging below 30 degrees, but who knows I may want to view something low (ish) with a EP (if I could remember where I put 'em). Adding a floor will increase the angle of viewable targets. I have other tripods and mount I could use to do visual with though, and that allows me mobility that a pier and observatory don't!

I set the walls up around the pier, mostly to check ground level(ness). When I walked into the circle for the first time I had a flashback to when our new house arrived. We walked in the front door and thought, wow want are we going to do with all this room. Once you start putting all your stuff into any structure the space evaporates pretty quickly!!!!!

Re: Base for Observatory

Posted: Sun Jun 28, 2020 5:03 pm
by OhNo
After weighing the pros and cons of my different options, plus the weather conditions and cost, I have made an executive decision. I went for the wood. I have good to great drainage, and the material cost and availability are manageable. With the footprint in mind the floor is 120 Square feet, which leaves a lot of exposed area outside the area that will be covered.

Orientation of the bays has been decided upon. Setting it so cable management and internet access came into that decision. Sadly if money (or limited availability of it) didn't play into the mix I would have probably altered the plan, but it is what it is!

Re: Base for Observatory

Posted: Sun Jun 28, 2020 6:55 pm
by Dragonsfire
Something to check into, a cheaper way to stabilize the ground is to hammer in rods into the ground for the foundation to lay on top, the rods create friction so minimized movement.
I have Use sidewalk blocks and in general their ok but walking around makes movement in the scope, this summer Im adding rods into the ground to stabilize. Dont recall the specs but can be searched.

Re: Base for Observatory

Posted: Sun Jun 28, 2020 9:28 pm
by OhNo
My pier is independent of my floor. It us just about too celebrate it's second year in use. At this time it has become very stable, and seldom requires a PA. If anything the 120 sq ft floor will help even more to stabilize pier movement due to keeping the ground dry under it. Living on a hill with a significant slope Helps to keep water from standing. My soil here is a dark brown heavy clay (Montmerilinit (sp)). The water table is 400ft below ground level. The well Granddad had drilled was a dry hole.

I am going to check in the morning to see If I can locate some crushed rock. The rock should extend the lumbers life span.

Re: Base for Observatory

Posted: Thu Jul 16, 2020 6:13 pm
by Kanadalainen
Hi Brent!

What a cool project. How deep into the clay does the pier go? Did you use a sonotube?

Re: Base for Observatory

Posted: Thu Jul 16, 2020 8:28 pm
by OhNo
Only about 4'. I used 7" tube from a retired Grain auger. Filled it with cement lifted a bit then pounded it back down a wee bit to put a bell at the bottom and cement around the outside to fill the hole. The top was 4 3/4" redi-rods ~18" long sticking up ~4"above the top to mount the lower portion of the mount base to.

The frost will/can go down over 8'. this thing has never moved. Drainage is good from the pier base, and I seldom have to re-set my PA. The Mount has never been off since it was first mounted, freeze or thaw cycle. But every geographic location has it's own unique circumstances....

Re: Base for Observatory

Posted: Thu Jul 16, 2020 9:35 pm
by OhNo
A few images.
20200627_212644.jpg
20200629_165133.jpg