Doug,
If that tower is actually so out of plumb that you have to fix it, this is what
I would do:
1. Bend the legs just enough, within an inch of the bottom, that you can push
the tower with significant force by one person BY HAND from ground level so it
is straight. Paint the bottom 16 inches of the tower and also coat it with
some roofing tar, at least where you hammered.
2. Drill four, six inch deep holes in the existing concrete in a square
outside the area taken up by the tower. Install and epoxy, if you have the
proper epoxy, rebar in those holes extending up about 15 inches.
3. Make a form around your existing base about 12 inches larger both length and
width than your existing pad X 16 inches tall. If the existing pad is 24" X
24", make the form 36" X 36". Install rebar in the new form above the existing
concrete pad and down into the new pour area.
4. Pour the new concrete using three plumb bobs (one on each leg) and with
tower perfectly plumb (check it with a good level on all three legs in the
direction where the guy wires will go to the anchors) and let it cure for
however long you want - 14 days should be good.
In my opinion there is a lot more potential for creating worse problems than
what you currently have in trying to move a 2000 pound block of concrete buried
3 feet in the hard ground with 20 feet of R25G sticking out of it. You
certainly don't want to put extreme force on one leg of the tower at 15 or 20
feet with a guy wire in an effort to move the concrete.
Remember that the only purpose of a tower base on a guyed tower is to keep it
from sinking in the ground. Originally you were going to have it sit on top of
a plate on your roof. Oh, yes, this is overboard, but probably less work than
trying to move the concrete.
Use good, temporary guy wires with proper tension and put up the last section
or two and antenna in a safe manner.
73... Stan, K5GO
> On Feb 11, 2016, at 5:51 PM, Douglas Ruz (CO8DM) <co8dm@frcuba.co.cu> wrote:
>
> Hi,
>
> I have been thinking and I am really want my tower straight and plumb.
>
> I am considering digging out some side of the base to adjust the tower level.
>
> Any tips or thoughts ???
>
> Can I just digging 2 sides or all 4 sides of tower bease???
>
> About backfilling...what is the best add concrete again for backfilling???
>
> what is the best method to move the base to adjust the level ??...it is about
> 2000 pounds base.
>
> Thanks in advance,
>
> 73....Douglas, CO8DM
>
> "No creo que haya alguna emoción más intensa para un inventor que ver alguna
> de sus creaciones funcionando. Esa emoción hace que uno se olvide de comer,
> de dormir, de todo." - Nikola Tesla
> ----- Original Message ----- From: "Steve Maki" <lists@oakcom.org>
> To: <towertalk@contesting.com>
> Sent: Wednesday, February 10, 2016 8:26 PM
> Subject: Re: [TowerTalk] My first tower section is not plumb...
>
>
>> If your tower is the equivalent of R25, and only 30', there's not much you
>> can do to it to really overstress it, unless you try real hard.
>>
>> But if you really want it straight AND plumb, consider digging out the
>> appropriate side of the foundation and letting the the concrete adjust
>> itself, and then backfilling it back in.
>>
>> At that point it will become what you want it to be, merely an anti-sink
>> device.
>>
>> -Steve K8LX
>>
>>> On 2/10/2016 8:08 PM, Douglas Ruz (CO8DM) wrote:
>>> Thanks for all replys.
>>>
>>> OK, first, I will build a Gin Pole...I think it is not a problem.
>>>
>>> Second, seems that my verticality errors are "into" the tolerance range,
>>> so,
>>> I think I can do some corrections before tighten the bolts...I put
>>> some pressure in one of the temporary guys and make the 2nd section plumb.
>>> In general the tower (only 2 sections now) is very stiff with "My temporary
>>> guy ropes"...I climb to the top of the 20ft to attach the line with
>>> weight (plumb bob) in the center of the tower and I dont feel any movement.
>>>
>>> My questions is:
>>>
>>> Can I try to make the tower plumb without adding to much stress to tower
>>> legs???
>>
>> _______________________________________________
>>
>>
>>
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>
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>
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>
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