Post installation question

[Brabo]

I'm going to be digging a post hole for my free (take it away please) 7 foot aluminum dish and was wondering what you guys think should be the dimensions of the hole. I used an angle grinder to cut the post from its original base so I lost about 10 inches in height, is that a problem? Thanks

 

[iammike]

The general rule is that the hole depth should be about one third of the total pole length. In my case, I have a 10.5 foot long pole so I dug a hole that was about 3.5 feet, or a little more, deep. I don't remember exactly what the width should be, but I think with a 4" OD pipe, you're probably looking at a width of 18 or 20 inches. It's also a good idea to put a piece or two of rebar through the bottom of the pipe to make it more torque resistant. You'll also probably want to fill the pipe with concrete when you're filling the hole.

FYI, digging the hole and setting the mast was by far the hardest work involved with installing my dish. Just remember to keep that pipe nice and plumb.

Mike

P.S. Just reread your original post. I'm thinking you lost a lot more than 10 inches when you cut away the post. There's probably a few feet of it still in the ground. It might be worth your while to check out your local scrap yards for a replacement rather than reusing the original.

 

[PSB]

Here is some good reading on the subject!

http://www.geo-orbit.org/sizepgs/grndpole.html#anchor72594

 

[Lynskyn]

Also use high quality concrete. Don't use "Quik-Rok" - it weakens the concrete - just concrete and let it set up at least 24 hours. I used to use 6 - 80 LB. bags of concrete for a 10' aluminum mesh dish. Definitely put some kind of "fin" on the pipe so it won't spin. We used to weld a piece of angle bar about a foot from the bottom of the pole.
If you don't have a way to weld, you can drill a 1/2" hole through the pipe and run a piece of 1/2" all-thread through and tighten it down with nuts.

 

[iammike]

Also use high quality concrete. Don't use "Quik-Rok" - it weakens the concrete - just concrete and let it set up at least 24 hours.

I'd let it cure longer than that. I let mine cure for a week prior to putting the dish on the pole. At least give it 3 days, but the full week is better.

 

[Greg Mueller]

I always go as far as my post hole digger will comfortably work, which is about 3'.

On the last pipe I got 9', which gave me 3' in the ground and 6' up. The dish is a 10' so the radius is 5', which gave me a foot of clearance between the edge of the dish and the ground when it is flopped over.

Usually I try to wait a few days before messin with the pole. 2 weeks will get you about 80% of the concrete's full hardness. The other 20% will take years

 

[Lynskyn]

I was able to get away with 24 hours back when I was doing installs for a living - but many times it was 90+ degrees outside. Never had a problem. But I was always careful to use HQ concrete and not use too much water. I did go behind other dealers and clean up their Quik-Rok messes many times. They would sometimes use as much of that stuff as concrete. They would set the post and put the dish up within 1-2 hours. A few months later, the "concrete" would be powder. Don't know how those guys slept at night.