I put the description in a picasa album with lots of pics.
The parts are 90% iron and steel. The principle is similar to that of a suspension bridge.

https://picasaweb.google.com/117339093468317576846/5mCameraCraneAndTripod

That's a size all right, but what is like for lateral stability? I mean the ties will keep it stiff vertically, but I can imagine it getting a sideways wiggle on with no lateral support.

Still put me in mind of what a lot of folk say is the best ever crane shot in 'Once Upon a Time in the West'

(2:09 all the way through to about 3:20)
Once Upon A Time In The West - Jill's arrival at Flagstone - YouTube (http://youtu.be/p1ow1b9ChvA)

Thats a dolly shot till 3:02 and then a crane.

Lateral stability is actually not much of a problem.. The ties are just to hold the cables when disassembled and to guide the A/V cables.

I have metal screws that hold things in place otherwise.
And the base is wide and really strong..