>Don't even think of pulling up 90 ft of tower on a simple hinged base.
>The forces at the BASE are ENORMOUS. The SAFEST solution is
>the old fashioned gin pole and rope assembly method of stacking
>one section at a time, starting with a temporary set of safety guys
>at 10 to 20 ft and permanent guys (3/16 inch EHS) at 30, 60, and 90 ft.
Hm... That's too bad. Do you think this is just impossible, even with many
people (up to 25 or so) trying to distribute the load across the tower? I've
also talked with the guy funding it and realized that it only needs to be
80feet tall. There is a real push to avoid having to climb it, but if it
can't be helped, it can't be helped.
>The (unapproved) method I use is to dig a 3 ft hole with a post hole
>digger, then use a square bladed shovel to make the hole triangular.
...
>guys for the first section until the first set of permanent guys is
>secured.
Well, we've only got about a week and a half of access to the place-it's a
pretty short project. I like the general idea of 4X4's though.
>My guys are secured to screw anchors which can be unscrewed
>when you leave. Be sure to use Preformed Guy Grips (not cable
I've seen these advertised and recommended all over the web. I don't quite
understand how they work, but definitely think I'll use them. Is there a way
of using both grips and clamps? Or does that not make any sense at all?
>clamps) to attach your guys. My 60 and 80 ft towers use one
>screw in anchor per guy direction. My 95 and 130 ft towers
>use two anchors per direction spaced 60 and 90 ft respectively,
>but these towers have Yagi's on top. Personally, I would feel
>comfortable using one anchor per direction for a 90 ft Rohn 25
>tower with only a light on top assuming *moderate* winds.
>Of course Two anchors per direction adds an extra safety factor.
I'll almost certainly go with two-its worth the extra peace of mind. There
will be people and structures around and I'd hate the tower to come down!
>Contact W7NI for Rohn products and advice.
Thanks for the recommendation.
>de Tom N4KG
-eric
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