Patrick - Others have already told you how to do this. A couple of thoughts - First, a non-idea which seems crude, but which works pretty well to start making your cardboard template, if you're not comfortable with taking the curve of the boat by measuring: if you have access to a thick strip of lead, such as might have come from an old plumbing pipe, you can lay out that strip in the bottom of your boat and take a nice fair curve from it, then transfer that to your cardboard template. Julio says a wire will do, for this - I haven't tried that, but I'd think you'd need a pretty thick wire. You'll need to do this in 2-3 stages, marking the place where you "measured" carefully, on your boat, on the strip, and then on the template each time (bilges, deck surface, etc). It sounds crude, and maybe it is, but it can save you some time. A much more elegant and accurate way is to take the curve directly from the boat by measuring distances each inch or so. This is probably best done by choosing a "horizontal" plans, marking it on the boat, and then measuring vertically at your intervals. These measurments can then be transferred to your template. Use a batten or a french curve to draw a fair curve from your measurements on the template. Make your template, try it in the boat, adjust dimensions as needed, and cut your bulkhead. I've preferred to use plywood rather than fiberglass board, maybe just because I have plywood around. Four mm okume, reinforced with a layer of 6 oz glass cloth on each side, is very strong. 1/4 inch marine plywood is more readily available, and also makes a good bulkhead - again, I've reinforced it with glass cloth both sides. The plywood bulkhead is fixed in place with 2 or 3 inch glass tape all around. Like everyone else, I've used 3 inch closed cell foam (sold by NOC and others) as bulkheads. It's easier to shape, little errors in configuration can be corrected as you jam the foam in, and it's slight compressibility avoids the "stress riser" you otherwise get from a hard bulkhead. (My Romany 16 got rammed into a rock while surfing a couple of years ago, and would have had no damage at all except that the aft bulkhead acted as a stress riser and the boat cracked just behind the bulkhead. All fixed now, thank goodness.) The closed minicell foam is sealed in with 3M 5200 or similar sealant, and it stays there forever! The sealant does take a week or so to cure completely, though. BTW - My small experience suggests that you'll never notice the difference in retained cockpit water in you orient the aft bulkhead just a few inches behind the seat, and orient it vertically. I think a vertical orientation makes the bulkhead easier to fit, and I've been pleased with how well the boat empties out during rescue practices.. *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
> > The closed minicell foam is sealed in with 3M 5200 or similar sealant, and it > stays there forever! The sealant does take a week or so to cure completely, > though. > For my wood stripper, I cut out foam bulkheads just slightly oversized, popped into place, and got a perfect seal without using any sealant. On my old kevlar boat though, the sealant has failed around the foam bulkheads because the kevlar flexes too much. *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
Is there a danger these could blow out in a capsize? I too used foam bulkheads in my stripper. I cut them quite a bit oversize so there is a very tight fit. I haven't sealed them in yet because I haven't varnished it yet, but I do have float bags in as well. Woody -----Original Message----- >For my wood stripper, I cut out foam bulkheads just slightly oversized, >popped into place, and got a perfect seal without using any sealant. On >my old kevlar boat though, the sealant has failed around the foam >bulkheads because the kevlar flexes too much. *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
Bhansen97_at_aol.com wrote: > A couple of thoughts - First, a non-idea which seems crude, but which works > pretty well to start making your cardboard template, if you're not comfortable > with taking the curve of the boat by measuring: if you have access to a thick > strip of lead, such as might have come from an old plumbing pipe, you can lay > out that strip in the bottom of your boat and take a nice fair curve from it, > then transfer that to your cardboard template. Julio says a wire will do, for > this - I haven't tried that, but I'd think you'd need a pretty thick wire. You could also get a flexible curve from an art or drafting supply shop. This is made of thin strips of flexible steel imbedded in rubbery plastic. They come in a couple of lengths and would be a tad safer than handling lead. My neighbour is an architect and occasionally tosses out sheets of used foamcore. I grab it from his garbage pile when I can. I used it instead of cardboard when I retrofitted a bulkhead. I find the foamcore easier to work with. I cut a piece slightly larger that half the width of the kayak and cut a rough curve larger than the kayak by eye. I then got into the kayak and kept shaving off strips of foamcore with a very sharp knife until I got a good match to the shape of the inside of the hull. I then used this half piece to make a full size one but cut it deliberately slightly larger. I shaved this down just a little until I had the full bulkhead shape. This way I could eliminate the errors I made in cutting the half-width form. I then traced this onto the plywood and had my bulkhead. This was perhaps slow but it worked. *************************************************************************** PaddleWise Paddling Mailing List Submissions: paddlewise_at_lists.intelenet.net Subscriptions: paddlewise-request_at_lists.intelenet.net Website: http://www.gasp-seakayak.net/paddlewise/ ***************************************************************************
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