Endgrain balsa core can give issues if it comes into contact with water or in this case somehow the core has delaminated from the deck skin. We often work on balsa core boats and although it is a structurally good product it can deteriorate very quickly if moisture is present. In this case it seemed that the polyester resin hadn’t cured properly and had caused a sticky type of residue on the surface of the balsa core. We removed the balsa which was not soft or rotten and replaced it with Coosa board composite. This was bonded in with epoxy and then glassed in with epoxy. The repair was filled and faired back into shape, the owner was confident to take over and finish the painting. While we were onsite we carried out a few other little jobs for him.