After a week of working on 2-dimensional pieces, the fuselage sides were placed vertical on Thursday and the students began installing cross braces and squaring the fuselage. By mid-day Friday the first cross braces had been tack-welded in place. This involves a process of fitting a tube, tacking it in, and then checking for square along the entire length of the aircraft. They are getting one of the worlds best lessons in applied geometry. Even with an elaborate system of baling wire and turnbuckles holding everything in place, the students were surprised at how much warpage you can get from one small tack-weld.
With the sides vertical and the first few cross braces fitted, the task of squaring the fuselage begins. We are now working in three dimensions.
[note: There were several images here but have been lost to the internet]