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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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 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 (www.pierplates.com) 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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Don't forget to insert a plastic bag full of dry sand inside the pier. It will minimize any vibrations.

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