Thanks for all of the responses and ideas. However, no seems to have
addressed question. I concede that the top section of the mast (i.e above
the tower and a few feet into the tower) should be steel - preferrably
chromolly. However, I can not locate a source for chromolly in Western
Canada so I guess I will have to use standard steel pipe. BUT why can't the
lower section of the mast - say the bottom 30-40' - be a much lower
strenght material than steel. Have I made an error in assuming that
essentally the major stress on the lower section will be rotational with
very small bending moment? Is there an ME in the group that can given me a
rough idea of the materials that will handle the rotational stress?
VE5ZX & G0TZX
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