"Curious that amongst all the posts regarding the esoterica of the various resin properties, no mention of the expected life span of the total structure is mentioned."
The oldest fiberglass
boats are still going strong, so no one knows how long they will last. I have had to have the gel coat completely removed from two yachts, and have them given the cure for blisters
. This is why I am going with vinylester, which was formulated to resist all kinds of corrosive environments. It is used in highly corrosive chemical factories worldwide.
I read a post recently on another thread where the poster is yet another rabid epoxyphile. He owned a boat in which there were balsa core deck delamination
problems, which he blamed on the use of polyester resins. Properly done, balsa / polyester decks are quite bullet proof. Contrary to his wild generalizations based on one boat, dropping heavy items on such a deck
does not cause delaminations. Batwing is just one example of a boat with a poly / balsa deck that has been campaigned very hard for 35 years with no problems with its balsa/ poly deck.
By properly done, I mean that the resin must be forced all the way into the spaces between the balsa core
squares, and attach to the opposite laminate face. I have my doubts about the use of core on any hull
made in a female mold
, if the design has a lot of compound curvature. My concern is the inability to check adhesion of the core to the laminate on the outside of the hull, and the gaps which the compound curvature create between the stiff, flat core and the curved outer laminate. You are supposed to use a lot of 'bog' in that circumstance, but that is hardly a light weight construction method, and you can't see if there are, in fact, voids.
I, too, am shocked at the construction I have seen on some recent boats I have seen at boat shows. I walked up to one large, beautiful power yacht about 6 months ago and deflected the hull inward with my thumb visibly enough for my wife to see the movement. That was just plain scary.