curing mast flex

[dunnsept]

I was working on my dish last weekend, scraping rust & old paint off to re-paint.. UHHH.. OOOPS.. leaned against the pole and the whole thing will flex to the side..
no wonder I can't target Ku birds easily (at least this is my excuse for now and I'm sticking to it!)

OK, so what are my options for fixes for some serious flex? The top of the pole/polar mount is about 6' off the ground and I really don't want to plant a new pole, move the dish if I dont have to.

I was thinking either:
a)find a chunk o pole thru neighbor with an ID that matched the OD of the existing pole. Cut new pole in half and basically clam-shell the thing over the old one and weld in place

2) cut a window in the side at the top, fill with concrete, weld patch over top of hole. this could be an un-known as I have no clue how deep this post goes underground. dont know how much cement it might take, altho I could calculate pretty close

c) weld angle iron on sides of post.. I have enough scrap angle left from making my beer brew sculpture

thoughts?

 

[caddata]

You could weld everything not tied down in the neighborhood to the thing and still not fix the problem. You haven't supplied enough information to diagnose the problem.

Where is it flexing?
If it's the post, what size is it?
What's it made from?
How deep is it in the ground?
Is it set in concrete?
Is the dish mount moving on the pole?

Be a little more specific and I'm sure someone will help you.

 

[Hermitman]

Since you have welding capability, how about an I-beam 1/2 inch smaller than the pole diameter (so it fits tight to the pole) and weld at the top, middle and bottom. I'll bet that'll stiffen it up. Good luck.

 

[Cadsulfide]

If the weight of a man can move your pole, mother nature can too. Sooner or later, it will either break off or flop over. I recommend fixing it before it breaks your dish.

 

[dunnsept]

You could weld everything not tied down in the neighborhood to the thing and still not fix the problem. You haven't supplied enough information to diagnose the problem.

Where is it flexing?
If it's the post, what size is it?
What's it made from?
How deep is it in the ground?
Is it set in concrete?
Is the dish mount moving on the pole?

Be a little more specific and I'm sure someone will help you.

the post is flexing from ground to top. push on the dish and it will bend the post.. can't be more specific than that really..
well, it doesn't "bend" it.. but the dish will move with the post if you push on it
post is either 3" or 3 1/2"
Steel of some sort
no clue how deep it is.. previous owner planted it in 1986
as far as I can tell the mount itself is not moving.. the entire pole is moving.

I have a feeling that it's fairly thin-walled stuff, that's why I thought about filling it.


thanks

 

[brentb636]

I'd fill it with concrete, since this will stiffen it below ground as well as above ground. Might not work , but it's pretty cheap. I assume the pole is plumb right now, otherwise, don't bother, put in another pole.

 

[dunnsept]

I went out and wiggled it again.. it seems solid at ground level.. the pole is just flexing above ground.. I think I'll start by filling it with concrete and see how it does..

steel post surgery coming this weekend ;-)

 

[eurosport]

It sounds like the whole concrete blob is loose/moving in the ground. My 7.5 was transplanted, and is "double-blobbed" ...meaning the old cement chunk was still on the pole, and I dug an extra-large hole, and poured new cement around it. Solid as a rock, and we get some pretty hefty windstorms down here. I believe this method will work for yours too. Edit: didn't see your last post while typing, if it's solid in the ground it may be rusting through...if that's the case, only a new pole will fix it properly.

 

[starman345]

What size dish do you have on this pole? Can you cut the pole down to a lower height?, Does it need to be 6 feet high? If its c band, no choice there but maybe a smaller ku?

 

[melgarga]

I guess I'm dense.

well, it doesn't "bend" it.. but the dish will move with the post if you push on it
post is either 3" or 3 1/2"
Steel of some sort

If it moves the post, but it returns to it's original positition, that seems to imply it behaves more like plastic/pvc than steel. (Ironicy, there is an currently an active thread on pvc for pipe mount as well.)
If the pipe/dish assy moves to a point and can be returned to the original location with some amount of force, your should be able to see the weakened, moving point, if nothing else at the point where it enters the ground. I've seen several that rust off at, or just below the ground.
I'm with Cad on this, pull the dish NOW, to keep it from falling and getting damaged under it's own weight. You will need to remove it regardless to address the pole issue, what ever it may be.
Standard ANSI 3" pipe is 3.5" od. This fits very nicely inside ANSI 3.5" sch 40. (appx .026" play) If needed, a ~12" or longer section can be used for 'coupling' two pieces of 3" using your arc welder to secure both sides. Using a long enough coupling section, it is possible to secure one side of the coupling with two 'thru bolts' at 90 degrees to each other, 4 to 6" apart. This would allow for removing/replacing (lengthen or shorten) the upper section at will.
Dont forget to add one or more horizontal protrusions fastened to, and at a right angle to the pipe in the ground/concrete to keep it from spinning, should the concrete cease adhering to the pipe properly in the future.

 

[Anole]

experience with 3½ and 6 inch:

This is an interesting discussion.
I wish we had some old-time installers to weigh in on the subject.

When I went to get my AMCI perforated dish (see signature for link), I found it to be free-standing, nine feet up in the air, on a pipe that's 3½ inch outside diameter.
The cement at the bottom was quite stable.
Still, I noted a slight springiness to the pole, if pushed at about shoulder level.
By pressing firmly, you could displace the dish & motor a tiny bit, and it would spring right back.
Nothing you could see, but you could feel it.

Since I had the good sense to cut the pole off at ground level (no more concrete digging for this lizard!) I came home with a 9' pipe.
Well, dropping that 3' in the ground, should mean the 6' sticking up, will be all the stiffer.

At the time, the slight movement didn't bother me, but maybe it should have?
My dish 'n motor are about as light as any. Perhaps that's why 3½" was used?
No, the motor only takes a 3½" pipe! That's the reason! -

On the other hand, the Birdview was on a 6 inch tube.
It's 9' long, buried 3' in the ground.
Pushing on the mount or dish does nothing.
You might as well push on a brick wall!

I don't have any plans to reinforce the 3½" system when it goes up.
Should I think about it?
The easiest way would be to weld something to the outside of the pipe.
Maybe even a length of rebar?
As I say, I have no such plans. But, I will follow the thread with interest! - :up

 

[1captain]

I went out and wiggled it again.. it seems solid at ground level.. the pole is just flexing above ground.. I think I'll start by filling it with concrete and see how it does..

steel post surgery coming this weekend ;-)

what you need to do is dig around the pole base in the ground an check the base of the pole for rust an if you see holes or most of the pipe rusted away, then a new pipe should be set, once rust has started with metal you can not stop it, but only prolong it with primers an paint. after you got it dug hit the pipe with a hammer an poke with a screw driver to check an see how bad the rust is. have seen many poles rust away just below ground level right at concrete line then the dish falls over an then all needs to be replaced. really the concrete should be above ground line. just had to replace a 10-ft 2 months ago that the pole rusted below ground level an dish feel over.

now if you do need to set a pole an you're base with concrete is good you can still use that same base, by cutting the pole an grinding the pole at the concrete level, then get a 2-ft of 2 1/2" pipe, weld 1/2 of it in the bottom of a new section of 3" pipe (3 1/2" OD pipe is all measured by ID) along with 3 or 4 short sections of short angle iron welded horizontal on the new pipe, (so the new concrete will not let it spin in it), dig around you're concrete in the ground, an set the new pipe inside the one that you cut off at concrete level, form up above ground, level it an mix some concrete up to fill you're form boards. it will be stronger that what it was at day 1, an you will a very strong base due to the extra concrete, also I put a pvc 1 1/2 with a sweep in it also to get you're 1-run back up the pole. now I have done several this way an have NEVER had a call back on a rebase of a pole.

good luck this is a lot of work

 

[dunnsept]

<snip>
Still, I noted a slight springiness to the pole, if pushed at about shoulder level.
By pressing firmly, you could displace the dish & motor a tiny bit, and it would spring right back.
Nothing you could see, but you could feel it.
<snip>

EXACTLY! That's how I should have phrased it. springiness.. it flexes to the side and then springs back into place..
I'll dig around the base and check for rust this weekend.

 

[linuxman]

The only certain way to "fix" it is to replace the pole and concrete.

If the steel is flexing now, it always will flex, and eventually will break off. The problem with welding angles or channel is that there will still be points where it will flex.

I know that's not what you want to hear, but long term, it's the best way.

I have never been a big fan of filling the pole with concrete. If it were a ten inch pole, then yes, the concrete would do some good, but a 3 inch inside diameter column of concrete won't help you much.

For 3 inches of concrete to do you any good, you would have to take the dish off anyway so that there would be no swaying at all during curing time, and you would need to let it set that way for about 3 weeks before putting the dish back on.

Just my opinion.

 

[Swamp_Rat]

Plus if you are thinking about concrete I would definitely put a couple of sticks of rebar inside the concrete to give it added strength.

 

[melgarga]

That's a good tecnique Cap, have you ever had problems with the concrete 'cold joint'? I think I would form it out a few inches from the existing concrete's edge and a few inches into the ground as well. With the soil we have here things tend to crawl with changes in moisture content if not secured some distance into the ground.
Another thing I would add is to install the 2 1/2 inch in as deeply as it will go in the ground side. No reason to shortchance youself over a couple of buck in price difference. 2 1/2 inch pipe is not very common, in the petro-chem industry anyway. The only sources I know of are drill stem and conduit. Also, if the existing pole is thinwall, as I have seen a lot of installs use around here, there will be considerable 'slop' in the fit.

 

[turbosat]

When we were in the middle of the major drought two yrs ago, I had 2 c-band dishes get wobbly, from the ground shrinking and contracting, and maybe not enough concrete in the first place. One was a 12'monster I didn't want to disassemble. I chained it to a nearby tree to keep it from falling while I dug out around it. Dug down below the concrete that was already there, all around the pole, and just poured more concrete, making sure the pole was plumb. After a couple of days I removed the chain and it was fine. That pole is still rock steady and in use with a 7.5 Perfect 10. I knew the pipes were good and not rusted out from old age, so I got by easily. Always use more concrete than you think you need, I didn't on a couple of poles and got to work on them again, in very hard dry earth/rock!

 

[dunnsept]

hmmm.. thanks for the input guys.. maybe what I'll do is plant the Perfect 10 somewhere else, switch the 4dtv over to that one. Then I'll have time to do the 9.5' properly while using the perfect 10. AND when I'm done, I'll have my 2 c-band dishes setup ;-)

 

[melgarga]

Now you got it going on Homie! Sounds like a clear case of resource expansion justification.
Way to go!
Turbosat that is a very creative solution. Maybe a little labor intensive on the digging, but certainly off set by the hassle of taking down a 12 footer and having to set it all back up. Not to mention the potential for dropping and damaging it.