[TowerTalk] Guying mast above rotor

[Roger (K8RI) on TT]

On 2/12/2014 3:12 PM, Dan Cisson wrote:

I had a TH-5 2' above the top of a 100' 45G, a 7L C3i 50M7 6-meter yagi, 
30 ft boom 15' above the top, and a 14' cross boom 30 ft up with 2 12L 
C3i 2 meter yagis and a pair of 11L 440 C3is inboard of those for about 
7 years.  Mast was 2" 1/4" wall, structural steel tube, with a short 
1.5" stub that held the cross boom.

The 7L 50M7 at 15' was fine, but on those high wind days, the cross boom 
would whip around like a Bluegill fly rod that had just tied into a 
record Bass.  It also withstood two major ice storms. The only real 
problem was it beat the snot out of a TB-3 and TB-4 while they were up. 
The races wore so badly that the top sat right down on the base.  The 
edges of the races were like razors.

I knew it was well beyond the ratings, but I just had to try it. <:-))

73

Roger (K8RI)

> Matt....an opinion only... You are really not accomplishing much if 
> anything...You say you are guying the mast 12 inches out the top of 
> the tower ?? All you are doing at this point is asking a storm to bend 
> the mast above the guy ring...Long masts are asking for trouble, there 
> is a heck of a lot of leverage on the top of a long mast in high 
> winds...You could possibly be OK with a 6 meter beam atop the mast, or 
> a 2 meter beam, its a gamble !!. But if you put up an antenna that is 
> much bigger than a 10 meter yagi,, you are asking for PROBLEMS !!I 
> have took down too many of them in my days of tower work.  Other 
> alternatives are another tower(probally not an option for most hams).. 
> or fixed antennas down the tower...It is expensive, but you can rotate 
> the complete tower!! I would check with antenna manufactures and see 
> how close you can stack their antenna to other antennas on the same mast.
> It will be interesting to see what other opinions you get here on TT.. 
> Good Luck, and be CAREFUL !! ,,Dan N4GNR
> ----- Original Message ----- From: "Matt" <bluewaterpro at yahoo.com>
> To: <towertalk at contesting.com>
> Sent: Wednesday, February 12, 2014 2:45 PM
> Subject: [TowerTalk] Guying mast above rotor
>
>
>> I know the subject line sounds dumb,, but I have 15' of mast above my 
>> tower and live in South Florida. Read on...
>>
>> Im thinking of putting a guy ring at about 12' above the top of the 
>> tower, and, only in event of a severe storm, attach 3 guy wires, 
>> which would be anchored in concrete, the cables sitting on the 
>> ground, affixing them to the collar in event of storm.
>>
>> I've also thought of having  short guy wires permanently mounted on 
>> the guy ring collar, with the short guy cables running down the mast 
>> to the top of the tower.  Then i could climb up and attach the guy 
>> wires, if needed. No need for a bucket truck.
>>
>> I think this would provide additional survivability to the mast in 
>> heavy wind
>>
>> Any thoughts on this? Good idea, bad?
>>
>> Thanks/73
>>
>> Matt w1mbb
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