Brief Description: Re-plumbing the fuel lines, part 1
I had originally installed beautiful braided stainless steel fuel lines from the wing fuel tanks to the fuel selector valve. However, once I got the wings on and saw the bend in the hose to line up and connect to the fuel tank, I decided this was too much bend and stress on the hoses and fittings to accept (image 1).
Solution: Install 90-degree bulkhead fittings at the fuselage wall, craft solid tube lines from the fuselage wall to the fuel tank, and order new braided lines to connect the fuselage wall fittings to the fuel selector valve.
The fuselage wall is actually composed of the outer skin, plus an inner wall plate inside the cockpit. There's an approximate 1/16" gap between the two, and I don't want to squeeze that gap with the bulkhead fitting. Image 2 shows two washers: The smaller one is a sandwich washer I crafted out of an aluminum bulkhead fitting washer: I sanded down the outer diameter so it would fit inside the existing fuselage side pass-through hole. The larger washer is steel, and I'll use two of those to sandwich down onto the inner washer. This puts the tightening stress on the sandwich washer while protecting the fuselage skin and inner wall plate.
