[TowerTalk] aluminum mast vs. tramming

[Stan Stockton]

Steve,

If you want to tram the antenna, in this case I would consider moving the top set of guy wires about 5-8 feet lower than where they are now and tighten them as if that's where they are supposed to be attached.  Tram the antenna to the tower instead of involving the mast and then move it up onto the mast.  Move the guy wires back up to where they were originally.

You may want to remove all the elements that are within easy reach from top of tower and put them back on once the antenna is in place.

73... Stan, K5GO



> On Mar 12, 2016, at 7:18 PM, Steve K7AWB <k7awbgoog at gmail.com> wrote:
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> I have an aluminum mast  (which is 2” OD and 0.25” wall and about 11 feet) out of the flat top of the Rohn 25.  Already I have a M2 17-element 2-meter yagi at the top of the mast.  Below that antenna, and right above the flat top plate of the tower, I want to put my Force 12 5BA 5-band, 15 element yagi.
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> With my other tower, 90 feet of Rohn 45, we put up a 6-element Force 12 Mag 620 the first time by simply dropping each of guys and reconnecting once the antenna was above each guy point.  The second time we put it up, after balun replacement, we used a friend’s tram line and back-stay – of course the mast was 2” OD and 0.25“ wall and heavy!  
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> I don’t think I want to chance the Rohn 25 at 102 feet with that drop-the-guy process.  
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> So the question is : will a tram line work or will I bend the mast?  Even using a back-stay might cause undue pressure and bend the expensive mast.  And a bent mast does not rotate nicely.  
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> Steve K7AWB
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> Nine Mile Falls, WA
> 
> DN17es
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