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POD-design for a new deck

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#1 mistyridge

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Posted 03 May 2013 - 04:01 PM

I am going to move my POD to another location on my property because several property owners to the south of me have installed very bright sodium vapor security lights. The new loction is flat with gravel over hardpacked decomposed granit. I propose to build a 10'X 12' deck constructed out of preasure treated 4X4s on 16" centers with trex or evergrain as the decking. The main cross supports will also four 4X4s set on concrete pier blocks. Will this structure be ridgid enough so that vibration will be minimal for visual use with tripod mounted scopes?

#2 StarmanDan

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Posted 03 May 2013 - 04:13 PM

Personally, I would build separate concrete piers for each tripod leg to isolate the tripod from the deck.

#3 mistyridge

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Posted 03 May 2013 - 06:31 PM

Thanks Dan. The reason for a wood and trex type deck was the ability to move the deck as it is built like a super heavy duty platform on skids and can be moved if needed as the best location is directly over or next to my gas and electric service lines. Probably not a good idea to dig for piers. Other areas have tree or structure blockage problems.

#4 StarmanDan

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Posted 04 May 2013 - 01:38 AM

If ya can't dig, then a few cinder blocks would do the trick as well. Anything to keep from setting the tripod directly on the deck.

#5 mistyridge

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Posted 04 May 2013 - 11:42 AM

I wonder if a deck can be built stiff enough so the vibration would minimal for visual use? I like the idea of being able to move the tripod. Cutting holes in the deck to put the tripod legs on blocks would work but then they will always be in the wrong place if I use a defferent mount set up. I have three.

#6 Calypte

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Posted 04 May 2013 - 01:34 PM

A few years ago a friend told me how he was going to build a deck for his scope, which was to be strictly visual. I suspected he'd have problems. He later reported to me that the thing vibrated so much, that it was useless even for low-power observing. Assuming it's possible to make a deck massive enough to kill the vibrations, if you've got that kind of money, might it not be better to install the scope on a pier that goes up through a hole in the deck? Or, build your deck, and put the scope somewhere else?

#7 Bob Griffiths

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Posted 04 May 2013 - 03:07 PM

As long as the tripod sits on the actual floor of the observatory your scope will shake.. Personalty I would just cut 3 round poles in the flooring for each leg so it would NOT be sitting on the atual floor..

I rarely use my low level deck any more in my backyard(8 inches off the ground on the low side and 16 inches on the upper level) because I have an observatory now...

BUT all I did with the deck was cut 3 holes in the decking and pounded in 3 short sections of 4 inch diameter PVC pipe and cut them off level with the decking floor...filled most of the pipe with pea gravel then filled the top 4 or 5 inches with sand..still works FINE..So well I could (if I was nuts) do jumping jacks on the deck and ot cause the scope to shape...

Still had to carry the scope outside and place each leg of the tripod inside the pipe (which are of course is completely isolated from the deck itself)

Since the deck was used for cookouts etc I made darn sure nobody "could" trip on the sand filled pipe.. in your pod it would not be a problem if the sand was level with the floor or even if the pipe was...

in MY observatory I used 2x12's as floor joists and placed them 12 inches on center...only needed a couple of extra 2x12's by placing them 12 inches on center rather then 16...

Bob G

#8 mistyridge

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Posted 04 May 2013 - 03:08 PM

You are right, espcially if the deck more than a foot off the ground and has any give to it. It will be like a trampoline. I am also looking at other alternatives. I do not want to pour another concrete pad.

#9 mistyridge

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Posted 04 May 2013 - 03:17 PM

Thanks Bob, The area I have laid out today is relatively flat, with a elevation change of about 8" in 10', and I only need a 12'X10' area for the three bay POD, I could go with concrete pavers on sand. I am open to other ideas. :question:

#10 StarmanDan

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Posted 04 May 2013 - 04:56 PM

Since you have multiple set ups you could drill holes for each tripod and use those plastic hole plugs like are use in desks to keep folks from tripping.

#11 mistyridge

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Posted 04 May 2013 - 05:58 PM

Good idea Dan. You are right I have a lot astro stuff which I use. I am also considering selling the POD and building a ROR observatory big enough to set up three scopes, my Dob and two GEM mounts.

#12 mistyridge

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Posted 05 May 2013 - 12:56 PM

After looking at all the alternative locations on my 10 acre property plus the good comments from the folks on this forum, I think I have the solution. Last night I took my 70mm scope with a small laser level mounted on my surveyers tripod and carried it around to various observing locations other than the light polluted area (current POD location). I found that the large level Parking area on the side of my house was perfect. The only problem was, its a parking area and not a good fixed observatory location. The other problem with this area, I would need to move around some trees in order to see various parts of the sky. This effectively eliminates a fixed observatory. My solution is to construct a storage shed next to the parking area big enough to hold all my astro stuff. This way I can leave everything assembled and ready to go. I only need to move my scopes no more than 50 feet in any direction, depending on what part of the sky I want to observe. I may need to get a smaller and lighter GEM for my largest SCT. :jump:

#13 mistyridge

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Posted 06 May 2013 - 11:36 AM

The storage shed design is moving along. It will be a combination scope/mount storage, computer room and warming room.......why didn't I think ot this first. :confused:

#14 rigelsys

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Posted 07 May 2013 - 06:43 PM

"roll out" observatory is such a more elegant expression!

mine is shown here

http://www.cloudynig...d=Observator...


Here's mine

The storage shed design is moving along. It will be a combination scope/mount storage, computer room and warming room.......why didn't I think ot this first. :confused:



#15 mistyridge

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Posted 08 May 2013 - 02:16 PM

That is exactly what I have in mind. Great idea. Mine will be 10x8 to house two scopes plus a small desk for my computer and charts. Good photos. I hope to have the shed done in about two weeks except for insulation and electrical.






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