> The only part of the project that seems hard is insulating the tower
> from ground - I refuse to pay for the turned fiberglass pieces that
> several market for Rohn legs, it seems like a foldover base which mounts
> to a product like "plastic lumber" which in turn is mounted to a buried
> base should do the trick.
>
One can get structural fiberglass shapes fairly inexpensively. Cost wise,
it's about the same as aluminum in the same size, and the strength is, to a
first order, the same as aluminum. It's twice as flexible though. What you
are looking for is "pultruded" fiberglass structural material. Box tubing, I
beams, angles, etc. One brand name is "Extren", but there are many
manufacturers.
Even the inexpensive "non-electrical" grade stuff has fairly good electrical
properties. I've used the green Extren 550 stuff in high voltage equipment
a lot.
Probably the only real issue is going to be finding someone who will sell
you less than a full 20 foot stick, if you don't need more. On the other
hand, you are going to need to build some sort of structure. You can "glue"
it with the appropriate epoxy, or just use bolts and nuts.
McMaster Carr might sell short lengths mail order.
Jim, W6RMK
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