Towertalk
[Top] [All Lists]

Re: [TowerTalk] Broken Rohn 25G Base Section

To: <towertalk@contesting.com>
Subject: Re: [TowerTalk] Broken Rohn 25G Base Section
From: Tony King - W4ZT <towertalk1@w4zt.com>
Date: Wed, 07 Jul 2004 16:06:25 -0400
List-post: <mailto:towertalk@contesting.com>

At 01:04 PM 7/7/2004, Melvin Brafford wrote:
On May 21 a storm took down my 100' Rohn 25G. <snip> The swaged ends are gone, and all I have left is the 3 legs which appear to be ok, and the 2 remaining cross and Z brace sets seem ok. I wonder if anyone would trust using the remaining base section stub, and if so how would you attach the next section above it? <snip>

Melvin,


A friend of mine had a tower come down almost exactly the same way. His solution was to cut off the stubs evenly, that is to say level, and then he obtained thick walled galvanized water pipe that would just fit inside the stubs. He chose a length that would extend all the way to the bottom of the base and six to eight inches above the cut point. He drilled holes in the tubs and bolted the stubs to the pipe with the same 5/16 and 1/4 inch bolts the tower uses. He then drilled the protruding ends of the pipe to match the holes in the bottom end of the tower section so it could be put in place and bolted as normal. He then sprayed the junction with a generous coat of cold galvanizing paint. This system worked for him.

Being a certified welder, I wouldn't recommend welding things to the stubs (or any galvanized tower sections) for three reasons. The first is that it is galvanized and to weld it you should grind off the zinc material before welding. Otherwise it generates potentially dangerous fumes. Second, if you grind and weld on the stubs, you've created a real potential rust problem. Third, the welding process could significantly weaken the structure you're trying to maintain.

Using the inserted pipe scheme is the least amount of work and expense and will certainly keep the base from kicking out. Be sure to use temporary guys on the first sections (I would stand two sections bolted together on the stubs) to insure you aren't depending on the base for safety of life. Two men can easily stand two sections up and sit them on the stubs.

Good luck with your project!

73,
Tony W4ZT


_______________________________________________


See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.

_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk

<Prev in Thread] Current Thread [Next in Thread>