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Let's re-evaluate the original premise
By:Paul G. Jacobson
Date: 3/1/2002, 11:12 am
In Response To: Strip: Take-apart bulkhead ? (Andy Waddington)

The original design concept we have been using maight not be the best way to go for all people and all uses, so perhaps there is another way.

The current plan is to create a joint by making a pair of closely spaced bulkheads and cutting between them. The kerf area fo the cut is then filled with a gasket material of some sort, and the parts of the kayak are reassembled by using bolts which go through the bulkheads, and pinch them together. With this system we add the weight of the second bulkhead, the fasteners, the gasketing, and all the epoxy resin and glass cloth needed to secure the bulkhead.

Since the bulkheads are being used to hold the kayak together, we woeld want to "beef them up" or reinforce them substantially over the usual bulkhead design. That adds weight to one bulkhead, and then we double that weight because we nee two of them!

One thought that came to mind was to not use the bulkheads for connecting the pieces, but to look for a better sealing method, and to secure the hull components in a different way. The idea would be to use some thinking from how flush hatches are sealed.

I don't have this completely thought out, but lets look at just one possible connection. In my mind I see the bulkhead at the front of the cockpit, and I'm thinking of cutting the boat apart half about 3 inches forward of that bulkhead. At this point the boat is gently tapering to a point at the bow.

After the boat is cut, the 3 inch stub of heuu land deck that remains in front of the bulkhead is lined with 6 inch stips, or 6 inch wide pieces of plywood which are epoxy glued to the inside of the boat. These project out another 3 inches past the cut, and are clamped securely while the glue sets up. After gluing, the interior part of this lip is glassed. The exterior part is then sanded to smooth it, and to make it taper slightly. You have to reduce it eough to accomodate the layer of glass cloth and resin which will be applied. You also want the front edge to taper a bit. A sealant, such as a silicone caulking is applied to the lip, covered with saran wrap, and the front end placed back on until the silicone cures. That should give a tight fitting seal.

The problem then is to find wide head fasteners (bolts) which could be inserted into holes located in the area where the front section ovelaps the lip. A hatch in the bow would permit a person to reach inside to tighten a nut over a rubber gasket and washer to secure the thing.
The stern would be handled in a similar manner.

This would eliminate two additional bulkheads, and leave both bow and stern pieces with open ends, allowing one to slide inside the other, creating two pieces of luggage (cockpit, and stacked bow/stern parts) To protec things a hard foam pad could reinforce the cut end, and even serve as a foam bulkhead once the boat was assembled.

Anyhow, this is just a thought. perhaps others can break out of the doubled-bulkhead "box" and suggest other methods.

PGJ

Messages In This Thread

Strip: Take-apart bulkhead ?
Andy Waddington -- 2/25/2002, 4:50 am
Let's re-evaluate the original premise
Paul G. Jacobson -- 3/1/2002, 11:12 am
Re: Strip: Take-apart bulkhead ?
david -- 2/28/2002, 9:11 pm
Re: Strip: Take-apart bulkhead ?
Andy Waddington -- 2/28/2002, 7:43 am
Re: Strip: Take-apart bulkhead ?
Paul G. Jacobson -- 2/25/2002, 9:34 pm
Re: Strip: Take-apart bulkhead ?
Rob Schaum -- 2/25/2002, 9:23 am
Re: Strip: Take-apart bulkhead ?
Rob Schaum -- 2/25/2002, 8:25 am
Re: Strip: Take-apart bulkhead ?
Eric -- 2/25/2002, 8:14 am