I want to build a freestanding crane in front of by garage with a top mounted bridge. Height 12', span 30', bridge 20', load 6000 lbs.

What size beams and posts will it take to do this?
Anybody know who can "engineer" this for me?
Who sells the parts I will need? ("I" beams at the steel yard ya, ya, ya. I know.)

Beat to fit, Paint to match
Need a bigger hammer and more paint.

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