On Monday 22 July 2002 10:12 pm, you wrote: > All this talk about gel coat cracks from the lack of structural support > makes me wonder why my Romany has developed cracks at, or near, the point > of contact between the bulkheads (all three) on both the deck and hull. > There is plenty of structural support from the fiberglass bulkhead--maybe > too much support? > > My boat is about 6 years old, and sees year round use on Lake Michigan, as > well as the occasional trip to Lake Superior, the Florida Gulf coast and > the Georgia coast. > > I just repaired the really bad "impact" damaged areas on the hull, but I'm > debating on whether to grind out the aforementioned bulkhead location > cracks--believing that it would be a futile attempt to repair without > figuring out the cause. While I do a lot of teaching, I don't think that > all those rescues are at fault. > > Anyone have any ideas and/or suggestions? > > John Browning > www.wildernessconnection.com Take a look at the book "The Boat Repair Manual by George Buchanan. Go to Chapter 5, Fiberglass Hulls. It has a number of good write ups on stress cracking and stress at the bulkheads. Also lots of good drawings. For example: "If a decision is made to remove and rebond a bulkhead, make sure that there is a gap at the perimeter of the bulkhead. This should be filled with a foam insert, before applying the fiberglass attachment flanges. This ensures that in the event of a severe localized impact the hull is supported by the flanges, and not by the rigid bulkhead. It does not however, inhibit the primary function of the bulkhead, which is to maintain the strength and symmetry of the hull." Between the text and the drawings he gets the points across very well. I am in the processing of replacing the foam bulkheads on my Kevlar Eddyline Wind Dancer. I am using 6mm marine plywood with fiberglass and epoxy. The extra weight is not an issue with me. I have gel coat cracks on my rear deck and I want to fix the source of the problem. In my case, instead of using the polyurethane foam between the bulkhead and the hull, I am using 3M 5200 sealant. From there I will build out the hull to bulkhead corners with foam then bond them together with fibergass/epoxy. The key thing is the foam or sealant between the hull and the bulkhead. There will be a little give at the joint because of the foam/sealant and the stress will be spread out on either side of the bulkhead by the fiberglass flanges. In my case, I am putting in two plywood bulkheads under the rear deck so I will have good hull support for doing paddle float rescues. My other concern is fixing the source of my current stress cracks and not getting new ones because I have switched from foam to plywood bulkheads. I am in the process of replacing the bulkheads right now. I have not tried this before. Get a second and third option on this procedure before starting. I like the pictures on your web site. Use to live up there. I like the weather better down here in Tampa, FL. Jan Mason td376_at_mail.anonymizer.com *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************Received on Mon Jul 22 2002 - 20:41:00 PDT
This archive was generated by hypermail 2.4.0 : Thu Aug 21 2025 - 16:30:55 PDT