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## Re: [TowerTalk] Guying a self-supporter

 To: Steve Maki Re: [TowerTalk] Guying a self-supporter "Roger (K8RI)" Tue, 04 Nov 2008 04:44:06 -0500 mailto:towertalk@contesting.com>
 ```Steve Maki wrote: > Roger (K8RI) wrote: > >> Hmmm This was supposed to go to the group, but apparently I hit the >> wrong key...again. >> >> >> K7LXC@aol.com wrote: >> >>> >>> In a message dated 11/3/2008 12:45:53 P.M. Pacific Standard Time, >>> towertalk-request@contesting.com writes: >>> >>> >>> >>>> This subject has been debated before. Your analysis of >>>> self-supporting >>>> >>>> >>> towers and guying is another example of misinformation! Let me suggest >>> you obtain the facts next time you post or other wise state that it is >>> your opinion. The company that manufactures the self-supporting towers >>> I use, RECOMMENDS guying ... fact! >>> >>> >>> >> Angles are the angle between the tower and guy line. >> You can get the same answers by using the Sin of the angle between the >> guy and ground. >> Top guys on 100' 45G 3 @ 660# tension. Cos(30)*660 = 571*3 = 1715 rounded >> Middle guys 3 @ 440# Tension Cos(45)*440=311*3= 933 >> Bottom guys 3 @ 440# Tension Cos(60)*440=229*3=660 >> >> Tower sections 70# X 10 = 700. >> Base section 35# >> Antennas and mast 300# >> Rotator 45# >> Coax and control cables 100# >> Guy bracket assembly 23# X 3 = 69# >> Total = 1249 Give or take a 100. >> Were I to use EHS guys instead of Phillystran I could easily add another >> 300 to 600# while the Phillystran weights well less than 100# per 1000 >> feet. >> >> That means they guys on my tower exert an additional 3300# on the base. >> That is well more than double the total tower and antenna system >> weight. Free standing, or Self Supporting towers are build >> considerably stronger than guyed towers as they have to serve the >> function of those guy wires internally. Some are designed to allow >> guying as well. The question them becomes, If permitted how does guying >> the self supporting tower affect the wind load and weight support >> ratings. Guying a tower with properly tensioned guys can easily add >> more than twice the load to the base. So a 1500# tower could end up >> with 4500# on the base structure. >> > > Now figure the leg compression (unguyed) during a strong wind. You will > find that it's MUCH greater, and concentrates on the downwind leg(s), > and the conclusion is that reasonable guying will invariably increase > the wind load rating of any reasonable tower. It's not surprising that > most manufacturers do not recommend it though - it negates the advantage > of the self support structure...duh. > > Of course the self supporting structure is far heavier and more expensive than the guyed structure. It also takes a lot more concrete in the base. OTOH it takes up far less space, too. Were I not retired and still working at my old job I'd have a pair of them up. Crank up AND self supporting. Roger (K8RI) > Steve K8LX > _______________________________________________ > > > > _______________________________________________ > TowerTalk mailing list > TowerTalk@contesting.com > http://lists.contesting.com/mailman/listinfo/towertalk > > _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ```
 Current Thread [TowerTalk] Guying a self-supporter, K7LXC Re: [TowerTalk] Guying a self-supporter, Mark Spencer Re: [TowerTalk] Guying a self-supporter, Roger (K8RI) Re: [TowerTalk] Guying a self-supporter, Mark Spencer Re: [TowerTalk] Guying a self-supporter, Steve Maki Re: [TowerTalk] Guying a self-supporter, Roger (K8RI) <= Re: [TowerTalk] Guying a self-supporter, Doug Renwick Re: [TowerTalk] Guying a self-supporter, Roger (K8RI) Re: [TowerTalk] Guying a self-supporter, Don Moman VE6JY Re: [TowerTalk] Guying a self-supporter, Richards Re: [TowerTalk] Guying a self-supporter, Steve Maki Re: [TowerTalk] Guying a self-supporter, Doug Renwick Re: [TowerTalk] Guying a self-supporter, ve4xt Message not available Re: [TowerTalk] Guying a self-supporter, Jim Rhodes Re: [TowerTalk] Guying a self-supporter, Roger (K8RI) [TowerTalk] Guying a self-supporter, Bill