Mast Installation

[pitord]

I just put over 3 feet under ground into concrete a 13 feet 2 inch steel pipe . I filled the pipe with concrete. I did not think, the pipe will be still "wiggling". What are my options as far as stabilizing the pipe.

[elgemcdlf]

I have the same issue. I really have not had that much problem with it. Once you get the dish aligned when it gets really windy you will lose TV here and there. I have been thinking adding legs to form a tripod for stability but I have other dishes so if it is bad enough I lose signal I just switch to a different dish until the storm passes.

[wejones]

Originally Posted by pitord

I just put over 3 feet under ground into concrete a 13 feet 2 inch steel pipe . I filled the pipe with concrete. I did not think, the pipe will be still "wiggling". What are my options as far as stabilizing the pipe.

Is the whole pipe moving, ie the concrete in the ground moving too, or is the pipe bending? I've never had to resort to filling a pipe with concrete, but I would have thought that would stiffen it up and stop it from bending, but maybe not. But if the whole thing, concrete and all, is moving, then, depending on what climate you're in, you might be able to widen the slab a bit. If you are in a cold climate, this probably won't work, because you can't get below the frost line without your dish falling over, but if you're in a warm climate, you might be able to dig down 6 or 8 inches all around the foundation out maybe a foot or so wider, and pour concrete. This might stabilize the thing a bit.

A little bit of "wiggle" from flex shouldn't be that much of a problem, depending on how big your dish is. In gusty winds, you may lose signal now and then, but most of the time it won't be a problem. If you have a very big dish, and the bend is permanent, then it could be a problem, since aim is more critical for a big dish, and a little bend may make alignment difficult. But for most dishes, this shouldn't be a problem. What size dish? What size pipe?

[rainman]

also if you have the pipe running close to a building you can anchor it off of the building.

[pitord]

Thanks for all the replies. The pipe is wiggling above the concrete level, the higher you go the more it wiggles, it does not wiggle at the bottom. I would guess at the top (around 3 meters above the ground) it moves maybe 0.5 inch if I slightly shake it. I wanted to install a motorized 100 cm dish on it, I am pretty much sure that after hanging the dish and the motor the whole thing will loose plumb right away. The pipe is maybe a foot from a wall so I was thinking about maybe anchoring the pipe to the wall, also I was considering steel guys (just don't know specifically how to do it).

[William Eng]

Originally Posted by pitord

Thanks for all the replies. The pipe is wiggling above the concrete level, the higher you go the more it wiggles, it does not wiggle at the bottom. I would guess at the top (around 3 meters above the ground) it moves maybe 0.5 inch if I slightly shake it. I wanted to install a motorized 100 cm dish on it, I am pretty much sure that after hanging the dish and the motor the whole thing will loose plumb right away. The pipe is maybe a foot from a wall so I was thinking about maybe anchoring the pipe to the wall, also I was considering steel guys (just don't know specifically how to do it).

If you have that much play in your mast, it would be best to start over. I have a 6 foot steel pipe, 3 feet above and 3 feet below. In the manuel, they suggest you cut the end of the pipe at an angle. I drilled several holes and put bolts through it. When the cement dried, nothing moved.

[elgemcdlf]

Originally Posted by pitord

Thanks for all the replies. The pipe is wiggling above the concrete level, the higher you go the more it wiggles, it does not wiggle at the bottom. I would guess at the top (around 3 meters above the ground) it moves maybe 0.5 inch if I slightly shake it. I wanted to install a motorized 100 cm dish on it, I am pretty much sure that after hanging the dish and the motor the whole thing will loose plumb right away. The pipe is maybe a foot from a wall so I was thinking about maybe anchoring the pipe to the wall, also I was considering steel guys (just don't know specifically how to do it).

Considering steel? Your first post stated it was a 2" steel pipe. What kind of pipe do you have?

[rainman]

Originally Posted by elgemcdlf

Considering steel? Your first post stated it was a 2" steel pipe. What kind of pipe do you have?

I think he was talking about guy wire Steve.

[pitord]

Originally Posted by elgemcdlf

Considering steel? Your first post stated it was a 2" steel pipe. What kind of pipe do you have?

It is a galvanized steel 13' (length) by 2" (diameter) pipe. The pipe is maybe 3.5' submerged into concrete, which means it sticks out into air around 9.5' above ground.

[elgemcdlf]

How much concrete do you presently have? Should be roughly 275 - 300 lbs. Seems odd to me if filled with concrete that it would sway unless it (concrete) did not flow all the way down the pipe and only the upper portion is actually filled. My pipe is about 14' out of the ground free standing and empty in the center. It really is not that big of a problem unless as Bill stated the pipe would bend/kink. I rarely lose signal on that dish. Only during very high winds/bad storms. That is with a solid foundation in concrete though. My pipe is standard black pipe.

[pitord]

Originally Posted by elgemcdlf

How much concrete do you presently have? Should be roughly 275 - 300 lbs. Seems odd to me if filled with concrete that it would sway unless it (concrete) did not flow all the way down the pipe and only the upper portion is actually filled. My pipe is about 14' out of the ground free standing and empty in the center. It really is not that big of a problem unless as Bill stated the pipe would bend/kink. I rarely lose signal on that dish. Only during very high winds/bad storms. That is with a solid foundation in concrete though. My pipe is standard black pipe.

I put 200 lbs of concrete into the hole and 25 lbs into the pipe itself. Just to clarify, the pipe does not bend/wiggle at the bottom (right at the concrete/ground level) at all. The pipe bends at the top (around 9.5 feet) from the concrete/ground level the most. The winds here are pretty strong I would say, last year my STAB HH120 rotor with 100 cm antenna got completely wacked.

[keebs]

i would start over. for a newbie its going to be frustrating enough even with a plumb pole. you are better than that, why would you want inferior ****? also when you get past your mast issues another thing to not forget is how you tighten your mast clamp. do it evenly. a little each on each bolt at a time. watch your signal as you are doing it. that was one of my mistakes at first. thats my two cents.

[elgemcdlf]

Originally Posted by keebs

i would start over. for a newbie its going to be frustrating enough even with a plumb pole. you are better than that, why would you want inferior ****? also when you get past your mast issues another thing to not forget is how you tighten your mast clamp. do it evenly. a little each on each bolt at a time. watch your signal as you are doing it. that was one of my mistakes at first. thats my two cents.

There is nothing inferior. You take the length of the unsupported pipe in relation to the weight in relation to the D. A 2" base over a 9.5' span will show movement. Even bridges sway (suspension). Without adding wires or legs, a pipe of 2" is going to sway when checked 9' away from the base. Mine is in the 13' range with considerably more than a 1/2" movement at the top.

[pitord]

Originally Posted by elgemcdlf

There is nothing inferior. You take the length of the unsupported pipe in relation to the weight in relation to the D. A 2" base over a 9.5' span will show movement. Even bridges sway (suspension). Without adding wires or legs, a pipe of 2" is going to sway when checked 9' away from the base. Mine is in the 13' range with considerably more than a 1/2" movement at the top.

I absolutely agree, it will always sway 10' from the bottom, thanks for the mental support, it is pure mechanics. This is what I came up with yesterday. I took the legs (guys) from a SUPERDISH (SuperDMount) Universal Dish Roof/Wall Mount and attached them to the pipe and to the wall behind, looks steady. I have to mention it here, the main mast/pipe in the SuperDMount and "120FM: Add a floor mount" is complete junk. I squeezed and flattened them both just by slightly tightening the dish mount clamp, when kindly asking to replace the mast (it was after 12 months warranty) I was called a jerk - aaah what a customer support.

[wejones]

With a dish that small, there wouldn't be that much flexing if you used a heavier grade of pipe. But I guess I'd have to ask..... why so high ????
Do you need the height to clear some obstacle? If so, is the whole dish clearing or just the center? Anyway, I just wanted to make sure that you weren't using the higher is better mentality associated with TV and other VHF type signals. For a sat dish, height doesn't matter unless you have to see over a house or something, and if that is the case, just make sure that the whole dish can see the sat.

Re the guy-wire stabilization, that isn't as easy as it sounds. I tried to help a friend do that once, and it was almost impossible to anchor the guy wires solidly enough to stop the dish from moving. It would almost require a concrete platform similar to what you have your pole in, going below the frost line, for each guy wire or stabilizer leg. This sounds to me like way overkill.

What I think the best solution would be is,
(1) if you don't really need the height, just cut the pipe off and mount the dish lower.
(2) if in fact you need the height, then I would really consider starting over, and instead of using 2" pipe, use a bigger pipe, like 3" schedule 40 or maybe even 3.5". The 3" schedule 40 is approximately 3.5" OD, and 3" ID, and heavy walls that won't flex much with a dish that size. I have a very heavy 10' dish on 3" sched 40, and don't notice much flex at all.
9.5' is way to high for cheap grade 2" pipe, and I'm assuming "cheap" because it wasn't specified as being schedule 40 or whatever. For something that high, you don't want to run anything less than schedule 40, and I would definately use a bigger diameter. Run the big pipe nearly up to the top, then have it reduce to the 2" pipe by having someone weld smaller pipe inside the bigger pipe. Ie 3" sched 40 will come close to fitting inside 3.5", and 2.5" comes close to fitting inside 3", etc, until you get down to the size you need. If you don't want to have it welded, you can also use bolts, but welding is better.

[pitord]

Originally Posted by wejones

With a dish that small, there wouldn't be that much flexing if you used a heavier grade of pipe. But I guess I'd have to ask..... why so high ????
Do you need the height to clear some obstacle? If so, is the whole dish clearing or just the center? Anyway, I just wanted to make sure that you weren't using the higher is better mentality associated with TV and other VHF type signals. For a sat dish, height doesn't matter unless you have to see over a house or something, and if that is the case, just make sure that the whole dish can see the sat.

Re the guy-wire stabilization, that isn't as easy as it sounds. I tried to help a friend do that once, and it was almost impossible to anchor the guy wires solidly enough to stop the dish from moving. It would almost require a concrete platform similar to what you have your pole in, going below the frost line, for each guy wire or stabilizer leg. This sounds to me like way overkill.

What I think the best solution would be is,
(1) if you don't really need the height, just cut the pipe off and mount the dish lower.
(2) if in fact you need the height, then I would really consider starting over, and instead of using 2" pipe, use a bigger pipe, like 3" schedule 40 or maybe even 3.5". The 3" schedule 40 is approximately 3.5" OD, and 3" ID, and heavy walls that won't flex much with a dish that size. I have a very heavy 10' dish on 3" sched 40, and don't notice much flex at all.
9.5' is way to high for cheap grade 2" pipe, and I'm assuming "cheap" because it wasn't specified as being schedule 40 or whatever. For something that high, you don't want to run anything less than schedule 40, and I would definately use a bigger diameter. Run the big pipe nearly up to the top, then have it reduce to the 2" pipe by having someone weld smaller pipe inside the bigger pipe. Ie 3" sched 40 will come close to fitting inside 3.5", and 2.5" comes close to fitting inside 3", etc, until you get down to the size you need. If you don't want to have it welded, you can also use bolts, but welding is better.

Thank you for the comprehensive post. My layout is that there is a 7 feet high concrete wall, 1 foot behind the pipe. I will come up with something to stabilize the pipe to the wall. It will leave me with around 3 feet of free standing pipe.