I clecoed the interior ribs to the bottom of the left skin in order to lay out the vent line. I unrolled a section of the 1/4" aluminum tubing and cut it to length with some extra margin. I used my spring tube bender to straighten the tube out as best I could. I located and drilled a hole in the inboard rib for the vent fitting per the plans.
After all my practice with the tool, I created a nice flare on one end for the fitting at the inboard rib. The challenge is to make the double bend in the tube for the inboard bay. I got pretty close using the tube bending tool. The picture below shows It off about ¼”. I think what I need to do is to get a stiff piece of wire and create a mockup of the geometry and then use that to get the final bend locations. Otherwise, it is a trial and error process.
