Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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The pier has been poured, but I didn't get to see it unwrapped before I hit the road again in the big truck. Vacation starts on or about May 25th, and the building itself will start going up around then. In the meantime, a few pictures of the start of this project.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Next..
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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And next...
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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It is an 8" diameter pier, approximately 6ft tall from the ground, as the floor of the observatory will be about 20" off the ground.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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rnoelle
super member
   
Reged: 01/23/08
Posts: 156
Loc: SW Oregon
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Hey Doug:
Congrats! Don't you love it when a good plan starts coming together. Looking forward to following your progress on this. You sure one pier is enough? 
Bob
-------------------- --Bob
* Meade LXD75 AR6-AT
* Orion EON 80ED
* Bogen/Manfrotto 475B; 501HDV
*
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Chris Schroeder
Postmaster
   
Reged: 12/11/04
Posts: 6523
Loc: N.E. WI Sky Glow
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Great start Doug, and concrete will have plenty of time to cure before you resume work, not a bad thing.
-------------------- Chris
Mallincam Color Hyper Plus
10" DSH with SC DSC, CPC 800 XLT
M110 Doublet ED, AT 102Achro, ZS80FD 10th Anniv, ZS66SD, PST
CG5-AGT, EZ-Touch, Voyager
POD XL3 http://POD.SchroederCity.com
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Project Galileo
sage
   
Reged: 11/14/07
Posts: 404
Loc: Douglas County, Colorado
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Enjoy! Good job!
-------------------- Orion XT10i
Meade LXD55 LXD75 AR-6
Sears 80mm f/15 3.1" Vintage Refractor
TeleVue Binoviewers with Seibert 1x/1.3x/1.7x OCA
Minolta 10x50 Binoculars
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csa/montana
Den Mother
   
Reged: 05/14/05
Posts: 39594
Loc: montana
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Doug, Congratulations on the start of your Observatory!
We will love taking the journey with you, building it!
-------------------- Carol
AstroTech 16" Dob (Thanks ASTRONOMICS!)
Vixen 80MF/AstroTech Voyager
Masuyama's 7.5, 15, 25W, 35mm,
Pentaxes; 5XW, 7XL, 10XW.
14mm Meade 4000 UWA
TV Panoptics; 22, 35
DreamCatcher Dobservatory, #2
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Thank you all. I didn't get to see it with the form removed, as I had to hit the road again. Dad removed the form late yesterday, and he says it looks really good. He's helping me to do this project, as he has built many small buildings such as this. But he's never built one with a roof that removed, and he is intrigued by the idea, and has come up with some interesting ideas on how to make it seal itself when closed. Ya'll will see it when I do.
Bob, you know one ain't enough, but it's a start!
Carol, you and others have inspired me to finally get going on this.
More will be posted as it goes along. It will restart the end of this month, when I arrive home for 5 weeks of vacation.
And ya'll might as well start adding your suggestions for a name. I'm drawing a blank so far.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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rsbfoto
sage
Reged: 06/10/06
Posts: 341
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Hi Doug,
I have been looking many many times on the pier you are building and allow me to give you some points of view from my side.
I do not want to take the wind out of your sails but I see some trouble coming up with the design of your pier.
Judging from the image you posted I can see that you did not go very deep into the ground with your base. The shape of that hole is also problematic as you have a narrower bottom then the top.
¿ Why do I say that it looks like trouble ? You have a 6 feet tall concrete post with a weight of maybe 350 pounds and the center of gravity is at about 6 feet high from the bottom. Now you will put on top of it how much more weight ? in equipment and suddenly your center of gravity goes up by maybe 1 or 2 feet maybe more depending of your equipment and your whole pier construction becomes unstable.
Judging from the image the diameter of the base at the top is maybe 32" but rapidly getting smaller the deeper you digged. So maybe you have there only a base with a size of 12" diameter and 12 inches deep ? That is a base weight of roughly 130pounds. Also I assume you went with the cardboard tube nearly down to the ground. The cardboard will start to rotten and then the concrete around will be of no help. If we add the weight of your base to the pier then maybe the center of gravity slips down by 2 feet.
The single rebar ? you put in there is not a big help for the concrete. Normally you have to put in at least 3 pieces tied together with some rings. Another possible problem is that you sticked the rebar directly into you soil which can be a future problem that you rebar will start rusting inside the concrete pillar. Water creeps up by capilaritybetween the boundaries of the iron rebar and concrete. From what I have seen rebar should never be driven directly into the soil.
From your equipment desciption I deduct that you are a visual observers which implies another problem that you will be movong the scopes and you personally could be leaning on the pier and ahving such a little base in the ground you pier can easily be moved by you and become unstable.
Apologies for beeing the first one to write about possible future problems ...
Just my 2 cents to your project.
You are still on time in order to stiffen the big 6 feet pier by adding a broader concrete base especially because you wrote that the deck will be 20" above the ground.
-------------------- regards Rainer
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Thanks for your concern. Except for the top 5", that ground is solid very hard clay. The pier will not move, having already leaned hard on it, it didn't budge. A 6ft high pier will not have a center of gravity 6ft above ground. It would be 3ft, and with the additional weight and footprint of the base you can figure the center is just about where the floor will be. We have no such thing as a frost line, so going deeper was not necessary. The hole is 22" deep, and 18" wide at the bottom. The picture posted is not the final hole. And the tube was set only 3" into the concrete. And that isn't rebar, it's fence post, and very strong, designed to set into the ground, with lots of knobby surface for the concrete to hang onto. This isn't the first concrete post we have done, just the first for a mount pier.
And after all that, should it develop problems, well I guess I'll redo it. But I doubt that will happen.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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rsbfoto
sage
Reged: 06/10/06
Posts: 341
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Quote:
Thanks for your concern. Except for the top 5", that ground is solid very hard clay. The pier will not move, having already leaned hard on it, it didn't budge. A 6ft high pier will not have a center of gravity 6ft above ground. It would be 3ft, and with the additional weight and footprint of the base you can figure the center is just about where the floor will be. We have no such thing as a frost line, so going deeper was not necessary. The hole is 22" deep, and 18" wide at the bottom. The picture posted is not the final hole. And the tube was set only 3" into the concrete. And that isn't rebar, it's fence post, and very strong, designed to set into the ground, with lots of knobby surface for the concrete to hang onto. This isn't the first concrete post we have done, just the first for a mount pier. And after all that, should it develop problems, well I guess I'll redo it. But I doubt that will happen.
Hi Doug,
You are welcome
-------------------- regards Rainer
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Well, viewing other projects, I may have made a mistake. I used four 1/2" threaded rods evenly spaced on a 6" circle in the top of the pier. I have an 1/4" thick aluminum plate arriving tomorrow to make a mounting plate out of for my CG-5ASGT mount. Going to try to duplicate the mount plate on the tripod. Not sure how this is going to work out.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Turns out I have the cure. I own one of the Orion extension posts for use with refractors, and it has what I need to make this work. I'll just reduce the post from 16" to 4", and fit it to my 1/4" plate.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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RobVG
professor emeritus
   
Reged: 01/09/06
Posts: 734
Loc: Seattle Washington
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Quote:
Going to try to duplicate the mount plate on the tripod.
I did that with my CG-5. I noticed the bottom "plug" that goes throught the hole in the tripod is tapered .040". I made the hole in the adapter accordingly but just recently realized the taper was probably just to make it easier to assemble.
This thread shows what I did and some other CNers ideas as well.
The alt/az "tang" is 6mm diameter x 1.00 pitch if you want to drill and tap your plate to use the tang from your tripod.
Looking good!
Rob
-------------------- C11 SGT(XLT)CG-5
Observatory (page 5)
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Doug76
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Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Good info, and the way I would have gone, if I hadn't looked on Ken Dauzat's site and seen his CG-5 solution. http://www.kendauzat.net/other.htm This is so close to the Orion extension post, in short form, that I figure it's the best solution.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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Pedestal
Post Laureate
   
Reged: 03/11/06
Posts: 3798
Loc: Smoggy Bottom, Baytown,Texas
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You could also weld tabs on the Orion extension. I made this one, it has a Dousat adapter in the top. See my post here. Hubert
--------------------
Hubert
---------------------------------
www.smoggybottom.org
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Looks workable, but I don't weld, and I think I have the solution.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Quote:
Hi Doug,
You are still on time in order to stiffen the big 6 feet pier by adding a broader concrete base especially because you wrote that the deck will be 20" above the ground.
On further thought, this isn't a bad idea, and I think I will. Thanks.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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Doug76
Postmaster
  
Reged: 12/05/07
Posts: 5494
Loc: SE Louisiana, future Texan
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Well, vacation comes in 4 days. I'll be busy with the observatory, in between fishing trips, of course!  Didn't want the thread to get too far down the list, or I might start another forgetting this one! I could use some good pics showing y'alls various solutions to the placement, type, and number of wheels used for the roof. I've built plenty of small buildings, but none had a rolling roof.
-------------------- Doug
Truckstop Astronomer
The Universe, the light of God, in all it's majesty
6 achro refractors 50mm-150mm
1 apo refractor 90mm
1 SCT 8inch
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