Gary K9GS wrote:
A local ham is giving me a 27 foot steel light standard. It is tapered,
going from about 8 inch diameter at the base, to about 3 inches at the
top. It is octagonal in cross section and has a wall thickness of
approximately 3/16 inch. They are originally designed to be free standing.
I want to use this strictly for supporting VHF verticals for packet and
perhaps small 6M and 2M yagis. Since I live on a hill, the height is
perfect for this application.
I have two questions:
1) How does one determine the proper size concrete base? The manufacturer
is unknown.
2) Does anyone have any ideas on how to best mount this thing? I have
thought of setting a suitable sized (8 inch OD) piece of well casing in
concrete, with perhaps 2 feet sticking out, and bolting the light standard
to the well casing after lowering the light standard over it. I will probably
have to fabricate some type of shims to take care of the taper.
Any other ideas?
73,
Gary K9GS
__________________
Perhaps make four brackets that will provide a tab to mount it to anchor
bolts in a concrete base and straps for two or three bolts to secure it
to the light standard. Don't scrimp on the straps. Use like 1 1/4 or 1 1/2
by 1/4 inch hot rolled bar. These would work with 1/2 or 5/8 anchor bolts.
As far as size of the concrete base there are soil conditions to consider
and the actual load you are going to have on this mast. Also what wind
conditions
it would subjected to.
Let's hear from all the mechanical engineers for base size. I would guess
2x2x3 foot would work as there is not much load on it.
Bill N5CMI
Plano, TX
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