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I need advice on what i should do to make a pier. how deep should i make a 24 x 24 x ??? hole for a 12" tube? I want to make it with concrete.also Can anyone lend some pointers? I will be using a cpc 1100 on a wedge with the orion short tube piggy backed for a guide scope.will i need a plate made? Please help if any of you have done this let me know. Thanks!!

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Its probably overkill unless you live far north where there is a deeper frost depth.  if you live in the south 2 feet is probably sufficient.  call your local building department with your city or county.  they can tell you what your frost depth is.  you will want to dig to the frost depth or a couple inchea deeper.

I have an 8" concrete pier build from scratch using this websie as a guide (especially in how to build the bottom and top plate). Here is a pic:
I too dug about 4 feet into the ground and it is proving to be plenty stable carrying a load of about 79 pounds (G11, CW and scope).

Very nice setup.

did you do a tube 4 feet into the ground or is there a base also? Nice set up by the way!!

To be honest, I used a post digger and just took an 8 foot Sono tube 4 feet into the ground. So far so good, like I said it is plenty steady for my set up. If I did it again I would go the extra distance and pour a "foundation" with rebar laid horizontally in the ground.

Thanks Steve!! I guess I will go deep and a little wide.where did you get your plates at?

I had them cut at a scrap metal shop in town. If I remember correctly I paid $20.00 for both of them. 10x10 inch and 1/2 inch thick and used 4 12mm threaded rods 100mm long.

Steve, I'm assuming there 4' of concrete pier above ground level, in a "had to do it again" scenario is that a good working height (a bit higher/lower?) Anybody else have thoughts on the pier height (minus the base/leveling plates+mount head). Thanks, Marc

I would not go any higher than 4 feet above the ground. I'm ~5'5" and can manage everything fine. It was the perfect height with the CG5 but now that I have the G11 it is a pinch tall. Most importantly, no one can see it above my back wall...

I did the exact same setup with mine too. 4 feet deep, 8 foot sonotube.

Putting more weight on mine now and planning even more weight, so I got a new pier from software bisque and will be digging a much more solid setup. Squaring the hole not just a post. Will be digging deeper as well, just to be on the safe side.

 I am a civil engineer so i hope i can help .  you should contact your city or county building department.  they will tell you what the frost depth is in your area.  mine is 30" here in salt lake city.  you want to dig to the frost depth or a few inches deeper.  this will avoid any upheaval from the freeze/thaw cycles.  as far as the diameter, get a 12" quiktube form from homedepot or lowes.  i purchased 5 #3 rebars from lowes and arranged in a circular pattern with rebar tie wires every 12 inches.  the length of the quiktube and rebars depends on you frost depth and how tall you want the pier above the ground.  keep in mind you want to keep the rebar about 2" from the bottom of the ground (where concrete meets frost depth) and same at the top of the pier.  uses roughly 15 80lb bags of 5000psi strength concrete.  get a Dans pier top plate ( for mounting.

Thanks for the reply Lisa. I went down 24'' square then also went with an 8" tube another 18" in the center. I got 2 free 1/2 " plates and measured and drilled the holes myself. Trying to save money for other things I need.




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