I’ve been continuing with my rear seat belt modifications. The shoulder anchors attach to hat sections, which are attached to the rear fuselage beltframe and skin.
I fabricated the hat sections from 0.080″ aluminum. The sheet stock is too thick to cut with shears, so I used a nibbler attachment for my cordless drill. It works as promised, creating clean cuts through the aluminum – however, the little “nibbles” it drops are razor-sharp, so best to clean up right away! The thickness of this metal also tested the limits of my 18″ metal brake, but I was able to successfully bend the angles. After fitting the hat sections, I coated them with black powder coat, so that they blend in with the carpeting in the luggage area.
For reinforcement, the skin gets a 0.040″ doubler and then the rib RF-RIB-201 also gets a doubler. I test-fitted the reinforcements with clecos, and it sure seems pretty sturdy. The heaviest part (the hat section) weighed in at 3.6 oz., not too bad. The hat section shares rivet holes with longeron 201, which helps reduce the number of new holes I had to drill.