The 25 was designed to have a water ballast tank under the forward step down. That had to have involved considerable stiffeners. Potter removed all that and did not replace the stiffeners with anything, leaving a very wide and long space between the main stringers from the fwd tank bulkhead to the forward end of the bunks. Also the main stringers don't go all the way up to the cabin liner. The net result is an inherently weak structure prone to deflection in and up. Blue Heron is the expert on this, I'm the one who got bit the worst.
I put in three new bulkheads, one at the point where the cabin storage area ends and the bunks begin, another directly over the place where I had the worst problem (end of the stringer), and a third partial bulkhead halfway from the cabin storage area to the forward tank bulkhead. The first two went all the way up to the inner liner and out to the chine. All are mounted on three layers of 1708 and a wide pad of thickened epoxy. This is almost certainly overkill. Blue Heron put in one addditional bulkhead, look at his thread for bulkhead position and an explanation of what we think caused this mess. Strick took a different course, but his boat had no signs of any problem. See his thread for detail.
I cut out the floor of the step down to get to all this. Worked pretty well, also helped me find and fix some rot in the balsa under the deck. There was so much glass, it felt solid, but rot was there.
Connor
Last edited by cdavisdb; 04-24-2012 at 03:47 PM.
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