3/8" square tubing cut to plans
for the hinges and ready to weld.
The hinges were tack welded
and then fully welded with gas.  
One warped during welding and
was remade.
Hard to see, but I am getting
ready to weld the hinges to the
right side frame.  I have straight
edges sticking up and 5/16th
tubes to set the distance from
the edge of the longeron.  The
canopy frame is held the 3/8"
space above the longeron by a
scrap piece of square tubing.  
The hinge bushings are already
welded to the underside of the
longeron and held in place with
clevis pins.  I rotated them up
and tacked.  Worked perfectly!