New 1/2″ Baltek end-grain balsa core cut and laid in place, ready for bonding to bottom fiberglass skin. Just forward of the mast hole can be seen two internal backing plates of G10 (aka FR4), which is an epoxy-impregnated fiberglass cloth laminate material. Just a corner of each (green) can be seen protruding from beneath the top skin. Everywhere there is a highly loaded deck fitting I will be incorporating this in place of the balsa core material; no external backing plates needed.
Internal bracing to support the sandbags which will be loaded on top of the balsa core to insure good epoxy adhesion to the bottom fiberglass skin.