http://hypography.com/forums/science...lsa-tower.html
http://hypography.com/forums/science...den-tower.html
Two threads here where we've discussed this before, you might want to take a read through them for some ideas
From your description, I notice the tower has an outward slant to the legs. Depending on how the load is going to be placed on the tower you may want to reinforce the rigidity of the legs by joining them near the feet, as well as placing a beam or two from the load bearing points to the feet.
Hope it helps
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Sometimes a Hypography Forum Administrator
"With a big enough engine, even a brick will fly." -Law of Aerospace
