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ssa
11-28-2013, 10:41 PM
Anyone have or seen a composite stringer boat were the fiberglass tape that lays on top of the stringer flange over onto the hull crack? And should the flange on the stringer be bonded underneath it to the hull itself? Was doing some degreasing in the bilge and found that its seperated pretty much the full length of both stringers. If the flange should be bonded before I retape it what would be the best solution? I'm thinking just mix up some epoxy resin with filler in it and applying that to the gap under the flange. It was never bonded from the factory which is why I'm asking. Wondering if only the core of the stringer being bonded was important. And the flange was never scuffed up before the fiberglass tape was applied which seems to be why I'm able to pop it off in long pieces with a putty knife. If anyone has dealt with this I'd appreciate your thoughts on repairing it.

DAFF
12-01-2013, 01:21 PM
I too have a few areas or this on my boat. I have a feeling this separation is likely due to water infiltration and freezing between the layers making them pop open. To fix I was thinking on trimming the loose layer off. Grinding both sides for good adhesion then re tape using new glass. As for re bonding I would do it too if you can get both surfaces cleaned and dry for optium adhesion.

Since I purchased the boat I haven't let it sit with any water in it, its stored inside 99% of the time and has been stored in a heated storage facility during the winters. I more less treat it like it is a wooden stringer built boat in trying to make things last. Just because it is a composite build doesn't mean its 100% weather resistant and it shows in some of the boats which come up for sale in this era.

ssa
12-01-2013, 10:50 PM
I'm planning on pulling the engine/trans after the first of the year were I can get to everything good. I believe I can take some sandpaper fold it in half and scuff between the bottom of the flange and the hull so the epoxy can get a good bite. Then scuff the top side up and over onto the hull to retape the seam. Then repaint the bilge before throwing it all back together. I found all of it when I was winterizing I was flushing the engine out good and had water standing in the bilge so I went around back to remove the transom plug and looked underneath and saw water running out in about 4 places it shouldn't be. So I removed the exhaust and started degreasing everything so I could seal leaks and found the tape cracks. Also degreasing I found that the drain plug hose adapter was the source of the oil so I can fix that while the engines out. So I guess on the positive side everything will be nice and clean and dry come next year lol.

cadunkle
12-03-2013, 11:53 AM
I've always wondered about wet foam in composite boats and delamination issues. Occasionally you head about issues but I haven't seen a thread anywhere where anyone has pulled the floor and checked for saturated foam and standing water. I have felt that regardless of wood or composite, the main problem is foam holding water, particularly if it freezes and cracks the glass, lifts the floor, etc... It may be worth cutting a hole in the floor in that area between stringers and digging through the foam to check if trapped water may be causing the delamination. If you find it dry and no delamination on inside of stringer just patch the hole and bond the bilge side where you have the issue.