Gentlemen,
I would be grateful for constructive comment on the following problem. I am
in the market for a couple of 100ft towers or masts, the problem is that in
the UK there are very few manufacturers or suppliers, and those that can
supply new, usually import their wares from abroad. However, one quotation I
received from a UK manufacturer was for approximately 12000 GBP per mast
(guyed), at the factory gate, carriage, guy anchorages and erection of the
masts being in addition. I look with envy at the availability of towers and
masts in the USA. But importing a tower/mast into the UK would mean
additional value added tax being added to the price, plus the cost of
carriage and insurance imposed at the port of entry. Supplies of ex
commercial or military towers/masts appear to have "dried up" as the scrap
metal men scavenge every kind of metal, so that it can be sent to China!
Looking back through my old copies of the ARRL Handbook, a few suggestions
were offered, such as using redundant Sears windmill towers, or building an
"A" frame support, or even a wooden lattice tower, and so I am thinking of
doing something similar. As many boys did 70 years ago, I grew up playing
with a "Meccano" metal strip construction set, and it occurs to me, that if
one used structural grade aluminium, and high tensile bolts, then it would
not be beyond the realms of possibility to set up an assembly facility in
the back yard, jig drill the bolt holes in the aluminium, for repeatability
and accuracy, and assemble four sided, 25 foot mast sections, as though one
were using a "grown up" Meccano set.
I know that the current metal prices may seem very high, but the price of
buying the metal and assembling ones own tower/mast may be considerably less
than obtaining one from the USA or even Japan. I would be tempted to "copy"
the mechanical design and dimensions of my existing sixty foot lattice
tower, which was made in the UK and I paid around 150 GBP for it back in
1979. Sadly Strumech are no longer manufacturing for the amateur radio
market, but the last of their production of the sixty foot tower, was priced
at around 5000 GBP. My Strumech P60 is of triangular section, with tubular
steel vertical sections and solid steel rods forming the lattice, the
junctions with the vertical members being welded, the entire assembly then
being hot galvanised.
Possible sources of tower/mast designs or design information would be very
useful, and I look forward to the groups response in due course, sincerely,
John G3JVC.
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