Hi Bill,
Thanks for all the recent help. Maybe now I can return the favor.
Below,
in bold type, I'll share some thoughts on your project.
>I am in the early planning stages for my next tower.
>This time around I'm going to take K4XS's advice
>(amongst others) and plant the first section in concrete.
>
>Assuming a base extending a foot or 2 above ground level has
>me puzzled how to handle the next sections.
This is a great start and will make things fairly easy.
>I'll be using a 20 foot mast. Starting out with it already
>inside the tower avoids some serious struggles up top.
>
>However it also means starting out with 20 feet of tower
>with the mast inside. I'm not too clear on a safe way to
>hoist 2 55G sections and mast vertical and onto the top
>end of the base section.
About 18 months ago, I installed two large F12 antenna, necessitating a strong,
heavy mast. I bought a 22 foot stick of 1026 DOM tube, 2" od with .250 walls.
Once galvanized, it's delivered weight was 105#. According to specs, your Rohn
55 weighs 95# per section, so you are looking at about 295#, total. The FIRST
thing I would do is use a couple of hose clamps to secure the mast inside the 2
sections of tower. Now you are dealing with one solid piece, rather than two.
At least that way, you don't have a loose 100# + weight banging around inside
the sections.
>In the past, it was no problem for me to hoist 2 25G
>sections (and no mast) onto a pier pin base alone.
>My first tower here was 55G. 2 of us were able to
>walk up the first 20 feet (again, no mast) and set the base
>plater over a pier pin.
>
>Somehow, 2 sections of 55G with 150 to 200 pounds of mast
>inside has me worried. Getting it vertical using another 2 sections
>looks doable - but manhandling it up and onto the base seems
>a bit tricky (every wonder why sections done want to fit at the
>least opportune times?!?)
>
>Aside from the obvious (crane) I'm wondering how you
>may have approached this task.
One possible option would be to take another 10 foot section of tower and place
face to face on the OUTSIDE of the base section. Clamp with "hose clamps" to
two legs of the base section. For added strength, you may want one clamp right
at concrete level and another near the top of the base stub. Then take a second
spare section and do the same on one of the other faces, then put a clamp or
two between these two pieces where they share a common corner, about head high
so they are locked together. You have just formed a triangular notch that your
"stacking section" will fit right inside, and it should have no choice but to
drop into place. You may even be able to toss a rope or cable over the top of
the temporary braces to help pull the stacking section into place easier,
basically using the temp sections as a makeshift gin pole. Just watch the
fingers, as there will be a lot of horizontal "z-bars" that could pinch. Once
your stacking section is plumb and bolted firmly in place, remove the temp
guide and "go vertical!" YMMV, but hope this helps.
73!
Mark, K5ER
>In reality, a crane may be a lot safer leaving me
>to rethink the installation sequence.
>
>73, Bill
>K2EK
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