Rick wrote:
On Mon, 27 Jun 2005 11:34:06 +0000 (UTC), "John"
wrote:

I live in Leeds where there is lots of redevelopment going on in the city
centre. I was driving through the other day and got wondering "How do they
build them and get the crane cab and boom up there?" Do they use another
crane? If so how did they build that one, did they use another crane? If
so....... Do we have a chicken and egg situation here? I have never seen
one of these things erected, they just seem to appear overnight. Is it the
crane fairies job to put them there?

Cheers

John


They build the top bit neer the ground, with another crane. The bottom
section of the upright has hydrolics, and jacks the whole lot up, a
new section is inserted, crane is now 20 foot higher. repeat untill
crane is desired height.

Rick

But once the development is finished, what happens if there is no clear
space to reverse the process? The jib must be detachable in some way?

MBQ