I put up a Heights aluminum tower in the Columbus suburbs in 1994 and took it
down when I relocated back to Virginia in 2010. My tower was over engineered
to hold over 10 square feet with the top section at 80 feet. I never went
higher than 56 feet with mine so the base was larger than required. At the top
I had a Mosley Pro67B 110 pounds, a heavy rotor and 12 foot mast. The tower
when taken down after 16 years looked like new with no signs of whatever it is
your describing. That same tower went back up later and is still in use today.
I knew of failures with aluminum towers in Columbus, and in every case it was
due to not using the correct base which allowed for water drainage at the
bottom. Water would get into the tower legs, freeze and split the tower at the
base.
I also had a 28 foot Rohn 25G tower that was attached to the peak of my garage
using a house bracket at 16 feet. I did not do any special bracing in the
attic of the garage, and only used a small quantity of concrete at the base.
It only held a small rotor with a 6 element 6 meter beam.
yrmv 73Dave -N4DB-
On Friday, February 13, 2015 9:21 AM, "Joe Subich, W4TV" <w4tv@subich.com>
wrote:
I saw plenty of Heights and Universal towers that were egged out
during my time on Ohio. Many of them had the bolts/nuts tightened
to the point that the legs were somewhat flattened but that did
not prevent "egging out". I know one old timer in the Columbus
area who replaced towers twice within 10 years - both times because
they were so badly egged out that nobody would climb them to repair
antennas.
Again after what I saw of those towers, I would not trust one here
in the higher/constant winds in Florida. If I had to use a free-
standing tower here, it would be the biggest sections available
from AN Wireless or a properly engineered commercial - Rohn SSV,
Pirod (if they're still around), etc. - tower with bolted flanges.
73,
... Joe, W4TV
On 2015-02-12 5:09 PM, n8de@thepoint.net wrote:
> Joe,
>
> The 'egging out' is usually caused by insufficient tightness in the
> original erection.
> Have had many (over eight) Universal towers since 1975, and only once
> did that factor into the situation ... my error is not retightening the
> bolts/nuts AFTER erection.
>
> Those 'light duty' towers are TV towers in my mind, and would never use
> one.
>
> 73
> Don
> N8DE
>
>
> Quoting "Joe Subich, W4TV" <lists@subich.com>:
>
>>
>> On 2015-02-12 2:00 PM, n8de@thepoint.net wrote:
>>>
>>> A free-standing Universal aluminum tower composed of 26" tapered,
>>> 22" tapered, and 18" topper will support ANY common
>>> tribander/vertical/VHF combo presently being used in ham radio.
>>
>> While that may be true in Michigan where the wind requirements are not
>> particularly high (70 MPH rev F, 90 MPH Rev G), that may not be true in
>> Seminole County, Florida where the building requirements are for 140
>> MPH (139) wind speed.
>>
>> Note the force due to wind is *2.5 times higher* at 140 MPH than at
>> 90 MPH. Directly comparing the allowable antenna in Rohn's example
>> designs for 90 and 130 MPH indicates the same tower will support
>> less than half as much antenna 1t 130 MPH as it will support at 90
>> MPH.
>>
>> Universal Towers does not even give windload data for 140 MPH on their
>> web site (they provide spec's at 80, 100 and 110 MPH for the light duty
>> towers but nothing for the heavy duty models) but given the nearly
>> constant winds in Seminole County, FL, I would *never* trust one of
>> their towers as I've seen how badly their bolted connections "egg
>> out" after only a few years in the much more calm areas of the Great
>> Lakes region.
>>
>> 73,
>>
>> ... Joe, W4TV
>>
>>
>> On 2015-02-12 2:00 PM, n8de@thepoint.net wrote:
>>> Unless he is intending to put up a stack of huge monobanders and/or
>>> SteppIR yagis, he doesn't need the 30" sections.
>>>
>>> A free-standing Universal aluminum tower composed of 26" tapered, 22"
>>> tapered, and 18" topper will support ANY common tribander/vertical/VHF
>>> combo presently being used in ham radio.
>>>
>>> Do the research ... I have 3 Universal towers up now ... and plan to put
>>> up 4 more soon.
>>>
>>> 73
>>> Don
>>> N8DE
>>>
>>>
>>> Quoting Gedas <w8bya@mchsi.com>:
>>>
>>>> Brian, I would not rule out a free standing tower esp since you need to
>>>> stay under 30'.
>>>>
>>>> I have several self-supporting Universal towers here, each of which
>>>> uses as their first 3 sections, their 30" HD series sections. When
>>>> assembling the towers and after getting those first 3 sections up in
>>>> the air, you realize how strong that structure is.
>>>>
>>>> In your case, since you mentioned 24', I would use two 30" HD sections.
>>>> See if you can get the top section modified either by Universal or by
>>>> a local welding/fab place to make it a topper with a collar where you
>>>> can then use a 2" or 2.5" mast. My gut tells me that two 30" HD
>>>> sections with a 4'-5' mast will still be standing long after your home
>>>> is leveled from some severe wind storm.
>>>>
>>>> Gedas, W8BYA
>>>>
>>>> Gallery at http://w8bya.com
>>>> Light travels faster than sound....
>>>> This is why some people appear bright until you hear them speak.
>>>>
>>>> On 2/12/2015 1:03 PM, Brian Carling wrote:
>>>>> Many thanks Bud.
>>>>>
>>>>> I will need to review which version they are using. Yes I had
>>>>> someone pointing me in the direction of a freestanding tower but I
>>>>> think I may go to using guys.
>>>>>
>>>>> It's either that or trade my tower sections in on a stronger better
>>>>> built freestanding tower designed for that purpose. I only need
>>>>> about 24 to 28 feet in height. Maximum.
>>>>>
>>>>> Best regards - Brian Carling
>>>>> AF4K Crystals Co.
>>>>> 117 Sterling Pine St.
>>>>> Sanford, FL 32773
>>>>>
>>>>> Tel: +USA 321-262-5471
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>> On Feb 12, 2015, at 12:27 PM, W2RU - Bud Hippisley
>>>>>> <W2RU@frontiernet.net> wrote:
>>>>>>
>>>>>>
>>>>>>> On Feb 12, 2015, at 9:58 10AM, bcarling@cfl.rr.com wrote:
>>>>>>> I am putting together a permit application with my city which
>>>>>>> requires certfication for 139 mph
>>>>>>> for three second gusts as in TI-222 spec. Also steady 100 or 110
>>>>>>> mph I think.
>>>>>>> We are making a 30 foot Rohn 25G tower according to the Rohn
>>>>>>> specification with 4 foot
>>>>>>> cube base of concrete with no guys.
>>>>>> I?m not sure I understand what you?re hoping to find.
>>>>>>
>>>>>> My 4-year old Rohn catalog makes it VERY clear that 30 feet of Rohn
>>>>>> 25 can hold only 1.7 sq. ft. of added antenna when the environment
>>>>>> is 90 mph (ANSI/EIA-222 Rev. E) and NO ICE. (For areas that
>>>>>> experience icing, Rohn 25 is specified by the manufacturer at ZERO
>>>>>> sq. ft. of additional antenna load!) From your e-mail address and
>>>>>> the wind speeds you mention, I?m going to guess you?re in Central
>>>>>> Florida, and I daresay a 90-mph Rohn EIA-222 Rev. E specification
>>>>>> is not going to be adequate for your city.
>>>>>>
>>>>>> Nowhere in your posting do you mention what total antenna, rotator,
>>>>>> feedline, etc. wind surface area or wind load you anticipate
>>>>>> putting on this tower. But my guess is that NO freestanding 30?
>>>>>> Rohn 25 tower is going to make the grade.
>>>>>>
>>>>>> Also, you fail to mention which version of TIA/EIA-222 your city is
>>>>>> using. The latest I?m aware of is Rev. G ? a substantial revision
>>>>>> from previous methods of specifying wind loading.
>>>>>>
>>>>>> Bud, W2RU
>>>>>>
>>>>>>
>>>>> _______________________________________________
>>>>>
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