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## Re: [TowerTalk] Tram rope

 To: "'Dennis OConnor'" , Re: [TowerTalk] Tram rope "Dick Green WC1M" wc1m@msn.com Mon, 18 Dec 2006 13:56:39 -0500
 ```I don't want to be contrarian, but has anyone seen a tram line made of reasonably strong rope break? Has anyone calculated the actual forces on the tram line? For example, the breaking strength of 7/16" nylon rope is about 4,500 lbs, with a safe working load between 450 lbs and 900 lbs (some references say no more that 1/5 breaking strength, others say no more than 1/10 breaking strength.) Would the forces exerted by a 100 lb antenna on a tensioned tram line exceed that? Also, the haul rope supports some of the weight of the antenna. Doesn't that figure into the equation as well? I ask this question because yesterday I successfully trammed a 44 lb Cushcraft 40-2CD to 110 feet using 7/16" 3-strand nylon rope. The next antenna to be trammed is an 81 lb SteppIR. Is there really a chance that my tram line will break? 73, Dick WC1M > -----Original Message----- > From: Dennis OConnor [mailto:ad4hk2004@yahoo.com] > Sent: Monday, December 18, 2006 7:27 AM > To: towertalk@contesting.com > Subject: [TowerTalk] Tram rope > > Let me second Dave's comment... Using rope for a tram line, > or small diameter cable is asking for a crash... I also use > only 1/4" EHS... Because the tram line is pulled into a > caternary shape the total forces on it are far greater than > just the weight of the beam... > The other thing I do is that the tram line is run up to the > top of the tower, through a pulley, and back down to a ground > anchor on the opposite side... This way the side thrust is > not transferred to the tower... Because of having to fly the > beam over the woods, etc., my tram line is 600 feet overall > and is kept on a drum and used only for that purpose..... > > denny / k8do > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection > around http://mail.yahoo.com > _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ```
 Current Thread [TowerTalk] Tram rope, Dennis OConnor Re: [TowerTalk] Tram rope, Dick Green WC1M <= Re: [TowerTalk] Tram rope, David Robbins K1TTT Re: [TowerTalk] Tram rope, Frederick M. Mott Re: [TowerTalk] Tram rope, K8RI on TowerTalk Re: [TowerTalk] Tram rope, Eric Scace K3NA Re: [TowerTalk] Tram rope, K8RI on TowerTalk Re: [TowerTalk] Tram rope, Jim Lux Re: [TowerTalk] Tram rope, Eric Scace K3NA Re: [TowerTalk] Tram rope, Dick Green WC1M Re: [TowerTalk] Tram rope, Eric Scace K3NA Re: [TowerTalk] Tram rope, Dick Green WC1M