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Re: [TowerTalk] Tower ACCIDENT

To: <towertalk@contesting.com>
Subject: Re: [TowerTalk] Tower ACCIDENT
From: "jeremy-ca" <km1h@jeremy.mv.com>
Date: Wed, 27 Jun 2007 20:27:09 -0400
List-post: <mailto:towertalk@contesting.com>
----- Original Message ----- 
From: "Roger (K8RI)" <K8RI-on-TowerTalk@tm.net>
To: "jeremy-ca" <km1h@jeremy.mv.com>; "Blake M" <n4gi@tampabay.rr.com>; 
<towertalk@contesting.com>; "Bill Winkis" <kc4pe@mindspring.com>
Sent: Wednesday, June 27, 2007 7:09 PM
Subject: Re: [TowerTalk] Tower ACCIDENT


>
>
>
>> First of all, ANY tower that is installed by burying a section should be
>> suspect UNLESS you are absolutely sure that the legs have plenty of
>> drainage.
>
> True as many even set in concrete may not have proper drainage.
>>
>> Drilling a small hole in the legs a few inches above ground can give you
>> an
>
> But ...ROHN doesn't even want the bolt holes, which will be too small,
> reamed or drilled out as it'll break the galvanizing which leaves bare 
> metal
> exposed. They expect the installer to use a "taper pin punch" to open the
> holes just enough for the bolt to slide in as a tight fit, but none of 
> this
> having to screw the bolt in.


Following that logic you then cant reuse tower sections if the galvy has 
been nicked. Obviously that is not real world reality.
And as I have mentioned earlier there are now several speciality coatings 
that can be used to prevent rust from forming and even smother existing 
rust.




>
>> idea if there is standing water. If the water is clear then it is 
>> probably
>> safe; if rusty then walk away.
>>
>> If its a dry hole at that level then snake some cotton string down the
>> hole.
>> If it comes back wet and rusty then Id also suggest not climbing.
>>
>
> It shouldn't normally come back wet. If it does the system doesn't have
> adequate drainage.


Duh, wasnt that my point?



>
>> New tower construction should always use a base plate and pier pin if the
>> only support is guy wires. If house bracketed then a minimum of 2 
>> brackets
>
> Not according to the ROHN catalog. You can use either the base plate or
> they build, or did, bases for both the 25 and 45G that are designed to be
> set in concrete which is what I used. The bottom ends of the tower legs
> supposed to set in between 6 and 8 inches of pea gravel. The concrete is
> poured over this while the tower base is inside the rebar cage. Yes they
> show two brackets and I believe the maximum above the top bracket is only 
> 15
> feet, but I'd have to look that up.


Rohn offers 3 mounts using flat steel plates. What I have done is use the 
idea of the self supporting mount, 25GSSB, which uses mounting holes in the 
4 corners. By drilling 3 holes and going from 5/8" to 3/4" bolts it 
increases the strength a bit. Probably not necessary, especially on short 
towers or light wind loads. The pier pin is not used on a bracketed tower.

The height above the top bracket that you are alluding to is for a TVRO 
dish. Using the HBUTVRO  bracket (not the lighter duty HB25AG or HBU) 
SECURELY fastened to the structure I see no reason that 20-25' cant be used 
with a typical 14-30 mHz multiband yagi.

 I will be going 30' above the top bracket for a 45G install to be used for 
UHF and above. My other 4 towers are 100-250' from the house which is 
unacceptable for the ultra highs.

Carl
KM1H




> Roger (K8RI)
>
>> is required. The base should be a standard base plate but with one hole 
>> at
>> each corner and secured to the concrete with 3/4"  J bolts.
>>
>> An existing tower that was installed without drainage MAY have its life
>> extended by drilling those small holes I mentioned. Then with ~ 3/16"
>> tubing
>> inserted down to the bottom regularly pump out any water. There are ways
>> to
>> derust the legs and seal against further rust but its an iffy proposition
>> when you cant tell the extent of the damage.
>>
>> Carl
>> KM1H
>>
>>
>>
>>
>> ----- Original Message ----- 
>> From: "Bill Winkis" <kc4pe@mindspring.com>
>> To: "Blake M" <n4gi@tampabay.rr.com>; <towertalk@contesting.com>
>> Sent: Wednesday, June 27, 2007 7:39 AM
>> Subject: Re: [TowerTalk] Tower ACCIDENT
>>
>>
>>> This information is all well and good ... it rings with a bell of
>>> caution ... BUT , how do you know .. ????
>>> In this case the climber felt all was well until the tower came down
>>> with him on it .. but now how in the world do you test and determine
>>> all is OK before you climb.?? Or what steps do you use to protect
>>> your self ...
>>> Certainly the professional tower people who partake in this forum
>>> will have a degree of in site for us .. but it needs to be
>>> discussed.!!! We've got guys here with 5-10-20 plus years old towers
>>> ....What is the answer??
>>>
>>> -Bill
>>>
>>> At 10:05 PM 6/26/2007, Blake M wrote:
>>>
>>>>If I had a nickel for every time somebody has told me this line....!!
>>>>
>>>>In my experience, what this really means is:
>>>>
>>>>"This is a hack-job install, but I really need to make you believe it's
>>>>OK
>>>>or else you're going to bolt on me and I'm going to have to fork out
>>>>major
>>>>coin for a crane."
>>>>
>>>>Simple psych 101.... If you have a pretty girlfriend, you wouldn't have
>>>>to
>>>>walk around telling people how pretty she is, now, would you?  ;-)
>>>>
>>>>Be safe....
>>>>
>>>>73,
>>>>Blake N4GI
>>>>
>>>>
>>>>
>>>>-----Original Message-----
>>>>From: towertalk-bounces@contesting.com
>>>>[mailto:towertalk-bounces@contesting.com] On Behalf Of Richard J. Fiero
>>>>II
>>>>W5TFW
>>>>
>>>>  The owner told me that he and his Brother Both men about 230 pounds
>>>> each
>>>>had been on the tower recently
>>>>at the same time and that it was strong as an ox.
>>>>
>>>>
>>>>_______________________________________________
>>>>
>>>>
>>>>
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>>>
>>> _______________________________________________
>>>
>>>
>>>
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>>>
>>
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>>
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>
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