The fuel tank was built up out of vacuum-bagged sandwich panels.
A number of tweaks were needed to fit the space between the boom and left wing root. A "dogleg" on the inside panel fits around the pod-to-boom brackets, and leaves space for the pitot-static tubes. Two carbon-covered-phenolic tubes were floxed into place to allow the aileron cables to pass through, and a sight gauge was left unpainted at the back. The sight gauge is visible through a window in the top of the pod. The "lid" of the tank has two bends in it, to follow the loft line of the airfoil. A single anti-slosh baffle is positioned in the center.
The tank is attached to the aircraft by two shear tabs (front and back), each made of an angle and shear plate (to eliminate a peel zone). A third tab down to the pod takes load under negative-g which would rotate the tank up and out from the boom. The tank rests on three base pads, made of spruce beams with carbon caps, with teflon anti-chafe tape.
The tank is finished on the inside with Jeffco 9700 epoxy sealer (which stands up to ethanol better than regular epoxy resin), and outside finished with PolyFiber Super-Fil epoxy filler, then primed with an automotive primer, and covered with stone gray Zolatone.
After the tank was completed and allowed to cure for a month+, I weighed it before and after filling with water to determine the volume, which came out to 8.5gallons. The sight gauge doesn't start to "work" until the tank is down to 3/4 due to the slope of the tank lid.
