Hi Gentles
Well, steel took its place in the jig (the wall and the floor with a bubble level, and a few sharps of wood to made all square).
A few knee calculations, and a fast read in NASA's welding book (dindnt work, or my reading couldnt get it). I made Stef's (dieselspaner) way: weld, angle grinder, weld again, a soft touch with angle grinder, and voilá! if not, repeat cicle!
After being satisfied, got supper.
Some pics for our members.
And, please stay safe.
VP
Ps: beam will be also 3" tube thicker wall, with a 2,5" thicker wall tube inside to reinforce (both 2m length). I'm expecting to lift my 12/2 with this crane. Any thoughts will be appreciated.