The fuel vent lines were fabricated today. They are shown below with the brake lines completed earlier. I was expecting the vent lines to be more trouble than they turned out to be. I began by putting the bulkhead fittings in both the side and bottom skins of the fuselage (inside the gear towers).
I then cut a 43" length of aluminum tubing and put a 90 degree bend in one end. I left about 2" of the tube after the bend to be flared and attached to the bulkhead fitting that goes out to the wing root. I then inserted it down inside the gear tower to determine where it should be bent at the top of the loop. I made two 90 degree bends where the line crosses the top of the gear tower. The width of the loop at the top is 3", the same as the diameter of the lightening holes. This allows the vent line to be inserted down into the gear tower through the top hole. It's easy to spread the loop a little after the line is inserted inside the tower.
Once the line was inserted back into the tower the length was marked where it attaches to the AN fitting in the floor. The last step was to put some plastic sheathing around the tubing at the top where it attaches to the gear tower, install the nuts and collars, and flare the tubes. After a final fit check, I fabricated the starboard vent line as a mirror of the port side. As with the brake lines, the second vent was easier to make.
