The fuel sumps are shaped using styrofoam as a mold. The foam was cut to close to the correct size. The rest was sanded down until it reached the correct shape. A place was left at the front of each sump to install a drain valve. The foam was then covered with plastic packing tape as a mold release. The fuselage and bottom of the strake was also covered in this tape. Peel ply was put down around the outside edges of the foam to treat the inside of the layup in preparation for its final attachment at a later date. The mold was then fastened in place using 5 minute epoxy.
