I have had a 60 foot Universal tower up for over 20 years. I moved two years
ago and moved the tower at that time. There has never been a problem. I did
obtain from the company (a long time ago) a study by a P.E. I believe he was
in Miami. From this was obtained a study that upgraded to 100MPH and I added
a 1.5:1 safety (ingorance?) factor. Now the bad news. The tower was taken
down with a crane with the following findings: 1)The sections were the devil
to get apart as they had basically almost fused together, but this should be
no surprise. 2) Most disturbing was the finding that the grade 8 bolts that
attach the legs at the bottom to the feet that were in the concrete base had
under gone electrolysis. They had virtually melted away. They were wasp
waisted in their mid portions and had deteriorated at that point that I
could easily bend and break them with my fingers. The base was in fair shape
with some rust and deterioration.
Universal sends the base sections painted and recommends that they be tar
dipped, as I recall. On this occasion I requested they be sent unpainted and
had them hot dipped galvanized. I would strongly recommend that the bolts
undergo periodic (not every 25 years) replacement. I believe this can be
done insitu one at a time on a calm day.
The only damage in the years was when a straight line wind estimated to be
about 100 MPH hit the neighborhood and did a large amount of damage to the
neighbor's houses, roofs off etc.(The old train coming sound) At that time a
tree fell and took two elements off the 205BA that was up. A few limbs hit
the tower, but luckily did no damage.
Would I use it again? I already have. It seems unlikely that you can go much
over 60 feet with much wind load, however. I don't think aluminium is a bad
construction material if used properly. This has already been a topic of
debate on the reflector.
Good luck,
sorry for the long wind
Sam Blackwell, W5LU
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