Using a Sonotube for installing a C Band pole

Not a good idea. It can end up spinning inside the hole (because it's too perfect a circle, nothing to "grab" the dirt), once the wind catches the dish. It's much better to just dig your hole a bit crudely with a post hole digger, and bell out the bottom, and place a bags worth of pea gravel on the bottom for ground water drainage. I also like to slightly notch one side a bit.

If you do it my way, once you shovel in the cement it catches in the nooks and crannies and helps to hold things against the dirt. Don't forget to also drill a hole through the bottom of the pole about 1 foot up, and shove a piece of rebar, or a large long bolt through it. That's to keep the pole from possibly getting twisted inside the cement, when wind catches the dish.

A 50 mph wind can create upwards of 500lbs of force against a dish...
 
It can be particularly difficult to attach/anchor things to concrete (assuming you can get the form off) where drilling, sawing and tapping work nicely with pipe.
 
Not a good idea. It can end up spinning inside the hole (because it's too perfect a circle, nothing to "grab" the dirt), once the wind catches the dish. It's much better to just dig your hole a bit crudely with a post hole digger, and bell out the bottom, and place a bags worth of pea gravel on the bottom for ground water drainage. I also like to slightly notch one side a bit.

If you do it my way, once you shovel in the cement it catches in the nooks and crannies and helps to hold things against the dirt. Don't forget to also drill a hole through the bottom of the pole about 1 foot up, and shove a piece of rebar, or a large long bolt through it. That's to keep the pole from possibly getting twisted inside the cement, when wind catches the dish.

A 50 mph wind can create upwards of 500lbs of force against a dish...

It always amazes me the lengths some guys will go through when installing a pole. I have been buying poles at the scrap yard for $15 or $20 (depending on who is working there when I go there and how much the pipe weighs) and typically these have a pretty good layer of surface rust which I just paint with Rust Reformer. I do not use pea gravel, I do not bell the bottom of the hole, I do not use 20 bags of concrete or anything like that. I whack the end of the pipe that's going in the ground with a sledge hammer a few times to slightly flatten it, then dig the hole with a post hole digger, then drop the pole in and center it in the hole (tamping it a couple times so the bottom goes into the sand a little), then fill the hole with concrete* (typically between 3 to 5 bags depending on how many roots I hit that had to be cut out or how much extra sand fell into the hole that had to be removed), then plumb the pole using a level on several sides, then tamp the concrete to get some of the air bubbles out, then check the plumb once more, then smooth the surface, then check the plumb once more to make sure it is absolutely vertical and then I leave it alone until the concrete dries. Whether because of the pitting on the pipe because of the rust or because I flattened it a little with a sledge hammer, I have never had a pole turn in the concrete on me, nor have I had the concrete turn in the ground.

Now maybe there are places where you have to do more, for example if you get hurricane force winds I'd probably want to do a little more to make sure it doesn't turn. We occasionally get straight line winds that can produce hurricane force bursts but only for a few seconds at a time, and those are very rare. Also I have hit plenty of roots when digging such holes, and they are a pain in the butt to try and cut out sometimes, but never rock - bedrock is probably a couple hundred feet down so no danger of hitting that. If the bottom of the pole hole were hitting solid rock, then I could definitely see where enlarging the bottom of the hole and using some sand or pea gravel for drainage might be necessary. One thing to keep in mind is that drainage really shouldn't be all that necessary anyway; the dish mount should cover the top of the pipe and at the bottom it will press into the sand or gravel. Now if you have that nasty clay that turns hard as a rock after it's been exposed to air, then that's probably where the pea gravel would be especially useful for drainage. But if the bottom of the pole is pressing into sand or gravel in the ground then it should be okay because you're mostly concerned with condensation moisture, and unless you have made your concrete mix far too wet it shouldn't creep under the bottom of the pole anyway, even if you forget to tamp the pole into the sand before shoveling in the concrete.

I suppose if you are on a mountaintop that is mostly solid rock and your frequently get high winds and occasional hurricanes or cyclones you have to do a lot more to keep your pole from moving and to provide drainage, but there are many parts of the country where doing any more than what I do really isn't necessary, other than maybe adding pea gravel or sand in the hole if you hit solid rock or clay. What's more than adequate and may even be ridiculous overkill in one area of the country is probably hardly enough in another.

* Actually before filling the hole with concrete I always run a piece of cheap black irrigation pipe up the pole a ways and down into the trench where my wire will go and tape it to the pole with duct tape, so that the wires can go through the concrete so they aren't as susceptible to damage by a lawn mower or weed whacker. If your ground wire is going to head off in a different direction you may want to put in a separate pipe for that. Typically i run the irrigation pipe all the way from the pole back to the house as it helps prevent damage to the wires from future digging, but not everyone may want to do that. Electrical conduit will also work but tends to be far more expensive, and it's not required for low voltage wiring, but it does look more "professional".
 
Lucky you. However, IMO, it's far better to do a bit of overkill the first time, then to have to possibly do it all over a second time. Or to have to try to repair a pole that end up leaning.

We have very soft sandy-loam ground, AND near constant winds of around 20~ mph. Our ground turns to pudding, IF it gets a soaker rain...
 
I suppose using rebar running through the pipe that's perpendicular to the pipe should prevent the pipe from twisting in the concrete. I suppose that could cause the entire concrete base to twist.
 
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Lucky you. However, IMO, it's far better to do a bit of overkill the first time, then to have to possibly do it all over a second time. Or to have to try to repair a pole that end up leaning.

We have very soft sandy-loam ground, AND near constant winds of around 20~ mph. Our ground turns to pudding, IF it gets a soaker rain...

Well then maybe you really do have one of those soil types where such extreme measures are necessary. I've never encountered that type of soil in my area - we have sand aplenty, but no loam, so any standing water drains into the water table before it has a chance to turn the ground mushy. In fact there are times I wish our ground were a little mushier in the spring, it would make it far easier to roll out lumps and imperfections! But I suppose there are places like yours where the ground turns to something akin to Jello in a hard rain. Still, despite all the talk about it, I have never actually heard anyone say that their pole turned in the concrete, no matter how high the winds. I suppose it is possible if you start out with a brand new galvanized pole that has no rust or other imperfections, and you made the concrete too wet (so it's weak after drying) or too dry (so it doesn't fill in around the pits and imperfections in the pole), or if you only poured a thin layer on top of the ground rather than filling the hole that the pole is in. It's one of those things that a lot of people seem to believe can happen so they try to guard against it, and that's not necessarily a bad idea, but I've never heard anyone say it actually happened to them.
 
I suppose using rebar running through the pipe that's perpendicular to the pipe should prevent the pipe from twisting in the concrete. I suppose that could cause the entire concrete base to twist.

Not if you use 3-4 bags of concrete (possibly a few more if your soils turns to Jello when it rains). And if you think that's really a possibility (AND you live far enough south that you don't get freezing winters or frost heave - see Titanium's comment below), the way I'd prevent it is by digging out a 2x2 foot square (or 4x4 foot square if you get hurricane force winds) the depth of a 2x4 (2x8 in hurricane areas) right around the hole where your pole will go. Then fill the hole to the top, level the pole to make sure it's plumb and maybe let it sit for a few minutes or so and check the plum again, and then carefully fill the rest of the 2x2 or 4x4 pad with concrete. Because it's a square pad sunk into the ground a ways it would be a lot harder to turn. In my area this would be complete overkill (and not advised due to frost heave) but soil types do vary and if you're one step above quicksand then this might be the better approach.
 
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In an area with freezing winters, NEVER pour a flat slab on the top. No better way to move the pole out of plumb than to let frost heave realign your dish with a heavy cold snap. This practice may work well as ballast in warmer regions with compacted soil, but one that I wouldn't use or recommend.

Best practice is to pour concrete in a drop or bell shaped hole with anti rotation measures. The minimal exposed cement surface area will be more resistant to movement during ground swell by moisture or freezing.

We should advise hobbyists of best practices rather than minimal methods that are prone to failure. I can't even begin to count how many systems I have reinstalled due to other installers shortcuts or poor construction practices. I am a fan of doing it right... once. :)
 
In an area with freezing winters, NEVER pour a flat slab on the top. No better way to move the pole out of plumb than to let frost heave realign your dish with a heavy cold snap. This practice may work well as ballast in warmer regions with compacted soil, but one that I wouldn't use or recommend.

Crap, I completely forgot about frost heave. :imshocked I have revised my post accordingly.

We should advise hobbyists of best practices rather than minimal methods that are prone to failure. I can't even begin to count how many systems I have reinstalled due to other installers shortcuts or poor construction practices. I am a fan of doing it right... once. :)

I agree but what is poor construction in one area might be more than adequate in another, depending on soil type, frost heave, maximum winds encountered, and probably a few other factors we haven't thought of. In any case I suspect it's the installers that try to cheap out more than the people who frequent this forum. I do, however, strongly suspect that the idea of a pole turning in the concrete, or the concrete turning in the ground is more urban legend than an actual problem in anything other than hurricane force winds and rain-drenched sand. That's why I suspect the slab technique I mentioned might be a good idea in (for example) coastal Florida or Hawaii or the Caribbean, but for the reasons you mentioned not in other places.

One trick I have seen on "professional" installations is that after dropping the pole in the ground, rather than using concrete they use some kind of expanding foam substance. I'm sure that stuff works well enough for fence posts but would it resist the wind trying to turn a C-band dish on the pole? My suspicion is no, so why do they use it? Oh, because it's quick and sets up faster than concrete.
 
I do, however, strongly suspect that the idea of a pole turning in the concrete, or the concrete turning in the ground is more urban legend than an actual problem in anything other than hurricane force winds and rain-drenched sand.

I suppose the chance of me meeting Bigfoot is rather good then... :eeek

I have repaired more than a few dozen spun poles through the years. Often this was done by busting out a few channels of cement and welding angle iron legs, then pouring epoxy or a cement cap.

Worked in varied environments. Have been a satellite technician in S. Florida, throughout the Caribbean and along the West Coast from Washington to California. You are correct, different techniques are used to suit each location. :)
 
Yeah, if someone has access to welding equipment it certainly wouldn't hurt to weld some angle iron or other scrap metal to the pole prior to pouring the concrete. In my case I don't have access to welding equipment, nor to a drill powerful enough to drill a hole through a steel pipe to stick a bolt or rod through it (at least not without a lot of effort), so I've never done it. I do try to flatten the pole a little with a sledge hammer, as I mentioned earlier, so maybe that's why I've never seen the problem. Then again we don't get the kind of winds you would have encountered in some of the places you've been for any prolonged periods. I am not saying I've never had a dish turn in the wind a little but in each case it was because I didn't tighten the bolts enough on the dish mount, because I'm always afraid of overtightening them and breaking them (I have done that before)!
 
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I didn't have welding tools or a powerful drill to drill a hole in thick metal so I installed a heavy duty U-clamp on the pole before I poured concrete. I believe that should be enough to prevent it from turning with wind load. Time will tell :)
 
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