Adriaan,
Funny, I didn't think of making the whole tower myself. Here is the type of tower that I plan to buy:
http://www.trylon.com/products/stocked_towers.aspxThere are many choices (also see the link below). I have bought used towers in good condition and I am looking for another tower that I can buy used so that I can afford a sturdy one.
I am using 4 anchors so that a square base can be made to stabilize not only the tower hinge but the gin-pole hinge at the same time.
The gin-pole, being a column in compression, leads to end-fixture loads and moments that you may be able to appreciate are very high, and permit early collapse of the gin pole if they are not controlled with sturdy hinges. The compressive loads are quite high when the tower is being tilted therefore both components of the base need to stabilize the system.
Mary,
I'm not against the tubular legs, but they do make the tower heavier = more difficult to tilt-raise.
I have looked at the Rohn towers, too. A Rohn 25G is much too small for a wind turbine. Perfect for my weather station, though.
By the numbers, this RSL is strong enough:
http://www.texastowers.com/rsl60l50.htmBut I don't disagree the tubular legs of the Rohn SSV are much much stronger.
They're also probably too heavy for me to deal with as easily.
I offered a few dimensions in the blurb, but I didn't make it clear - this will be a fairly big tower and I'm aiming for 60 feet, too.
This is one idea I have for an adapter that allows the tower to hinge up with a gin-pole but easy to tighten and secure once it is up.
The clamping on the hinge tube restricts the "wiggle" that you would get on crappy bolts like the ones on the hinge of that Rohn tower in Mary's attached photo.
Here's a picture of the similar base that I built for my radio tower a few years ago: