Although they aren’t really that old I’ve replaced a lot of bottoms on Hackercrafts . They are nice looking boats , good designs , nice hardware and they run well . They suffer from a lot of bottom problems though . Most of the ones built in the 1990’s had Ash frames , and the bottom planking was luan sub-floor plywood . The thinking when they were being built was that the epoxy would protect the wood that had little inherent decay resistance and rot wouldn’t be an issue . Unfortunately if the smallest amount of moisture finds its way into the wood , the wood will expand and crack that rigid epoxy barrier . This allow a bit more water in , and next thing you know there are mushrooms growing in the bilge . I Use penetrating epoxy to seal new wood in bottoms that I do , but the structural joints are bedded in 3M 5200 . That stuff will allow a bit of flex , –Unlike epoxy , which will just fail . I hand select every piece of wood and make sure that there is no sap wood ( outer part of the tree ) going into the boat
