[TowerTalk] mast material

[k1xx at cfl.rr.com]

Julio:
I don't totally agree with all your statements regarding top rails.  I've used them very successfully in the past.  Since this goes back a few years, my memories a bit fuzzy.  But, I seem to recall that there might be a heavy duty top rail which is "just slightly" under 2 inch OD and not much smaller as you mentioned.  I'd have to go out back and measure one to determine the actual size.  

In several cases, I used 12'ish foot lengths for yagis mounted at the top of the tower with the rotor recessed 10 foot into the tower.  In one case, I had a full 20 foot length with a custom-turned insert placed down into the top rail.  This one had a big  6 element 10 meter beam on a 3" boom at the very top (10 foot out of the tower).  I can't count how many ice and snow storms that combo survived.

If any mast material's overloaded, it will bend.  Doing the analysis is the first best step.  

73 charlie, k1xx