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Re: [TowerTalk] Fwd: Strain releif for vertical coax

Subject: Re: [TowerTalk] Fwd: Strain releif for vertical coax
From: "Roger (K8RI)" <>
Date: Mon, 25 Aug 2008 02:46:45 -0400
List-post: <">> wrote:
> In a message dated 8/25/2008 2:48:23 AM Greenwich Standard Time,  
> writes:
> Dave,  K1TTT, gave me the advice to tape the coax to the tower legs. Just   
> plain, good, electric tape
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> I posted on this concept before. 
> I used to buy and sell tower back in FL before moving out to KH6.  I  
> regularly used electrical tape to secure coax.......until I had a chance to 
> see  what 
> could happen in a corrosive environment. 
> Upon taking possession of a used 300 foot Rohn 55 tower that had been up  for 
> about 30 years and had been located about 1/2 mile from the Gulf of Mexico,  
> I discovered some oxidation and surface rust on the sections,  no surprise  
> there.  But, under the electrical tape from around 250 to 300  the  tower was 
> actually rotted through..My guess is the salt from the air had been  
> concentrated and had been pocketed in the tape around the coax.
> After that day I used nothing but UV cable ties.
Good broad UV *resistant* ties work, but they also present a place for 
water and particularly salt air to accumulate.
As to how good are they?  When I installed the antennas on the 45G I 
used the 1/2" wide, name brand, expensive, UV resistant ties that come 
from the electrical supply houses.  They had been up several years and 
seemed to be holding solid.  Pull on, or out on the coax and it appeared 
to be solidly anchored. However I needed to move a couple of the runs.  
I figured I'd just lift the little tab and loosen them enough to move 
the cables. When I started to apply pressure on the first one the tie 
snapped in two right where the strap enters the clip.  Coincidence?  I 
tested another by sticking a screw driver under it.  It only took ounces 
of pressure to snap the ties. Had they been left alone they'd probably 
have lasted 4 or 5 more years...maybe.   Remember this is the frozen 
North where we receive only a fraction of the sun / UV that the  Souther 
states  get.  I went back to tape. However I only wrap a tape width, or 
slightly more and do so about every two feet. 

I had one of the old American Steel towers up for 15 years or maybe a 
few more. The tape took the paint right off.  However there was never a 
rust problem on the tower... that is except for the bolts and galvanized 
guy wires.  When I took it down I ended up twisting about half of the 
bolts in two to get them off the tower. The guys were still far stronger 
than needed, but the surface on all of them was brown.
> Bill KH7XS/K4XS
Roger (K8RI - ARRL Life Member)
N833R (World's oldest Debonair)


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