Simple math says 3 inches is 1/4 of a foot. 1/4 of a foot divided into 40
feet is 0.00625 or a shade over half a per cent.
Now, I am not an engineer and I haven't calculated the stresses involved.
But, it is quite possible that any cure will be worse than the disease.
Before doing any tampering with the tower, I'd get competent engineering
advise. Weakening the legs to straighten the tower that little bit might
actually be a poor trade-off.
WO7R
On Thu, Feb 11, 2016 at 10:30 PM, Ron W8RJL <youngron@verizon.net> wrote:
> His tower is only out 1.5 inches at 20 feet which would be 3.0 inches at
> 40 feet his final height. I think he should put guy lines on it, go to 40
> feet, make sure the tower is straight (even at an 3" angle) then put an
> antenna on top, go inside and work a contest.
> Ron W8RJL
>
> ----- Original Message ----- From: "Stan Stockton" <wa5rtg@gmail.com>
> To: "Douglas Ruz (CO8DM)" <co8dm@frcuba.co.cu>
> Cc: <TowerTalk@contesting.com>
> Sent: Friday, February 12, 2016 12:11 AM
> Subject: Re: [TowerTalk] My first tower section is not plumb...
>
>
> 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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>>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>>
>>>
>>> _______________________________________________
>>>
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>>>
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>> _______________________________________________
>>
>>
>>
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