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put a cork in it, so to speak :)
By:Paul G. Jacobson
Date: 6/13/2001, 9:03 pm
In Response To: putting a bulk head in??? (Jim P)

the easiest method for putting in a bulkhead is to use a plug made from closed cell foam (minicell). Cheeck your legroom to see how far forward you want the thing, and place a few dabs of masking tape on the inside of the boat at the spot you want the bulkhead to go. This spares you from marking up the interior with a pencil. Just pull off the tape when you are done and you leave no marks.

Now get two pieces of cardboard, and a drawing compass. The kind that grammar school kids use for drawing circles is jsut fine. One piece of cardboard should be bigger than the inside of the hull at the point where the bulkhead goes, and the other is smaller.

Carry the smaller one inside the hull, hold it roughly in place, and "scribe" the hull shape on it. You do the scribing thing by opening up the compass about an inch or 2, then place the pencil point on your cardboard, and the pointed end of the compass touches the inside of the hull.

Move the compass so it goes completely around the inside of the boat, trying to keep the thing perpendicular to the hull at all points. If you wrap a dab of masking tape around the point of the compass it won't scratch the hull.

Now remove the small cardboard from the hull and set it on top of the large cardboard so you can transfer the marks. The compass should still be set towhatever opening it was at when you scribed the inside. This time you'll go around the line you drew on the small cardboard, following that line with the pointed end of hte compass, while the pencil end draws out a close approximation of the inside hull shape. Now cut the larger piece of cardboard so it is a bit larger ( 1/8 t 1/4 inch) than the line you've drawn. Take this cardboard into the inside of the kayak and see if it fits. It should be a bit large, and odds are it will have some spots that stick out more than they should. Trim those away first.

You'll eventually work your way doewn to near the line, trimming a bit here and there until the thing fits. If you cut too much, you can tape a piec of cardboard back on and try again. It takes longer to describe than to actually do this. When you are finished you'll have a pattern that mattches the inside curvature of your hull at the point you want to insert a bulkhead.

Now you have a few options on materials and installation.

You can just set your template on a piece of foam and cut out a foam plug. Shove the thing into place and you are done. Go paddle.

Or, you can get a bit more complicated. If you want to be able to remove the plug easily so you can use the enclosed area for gear, then you my want a handle on the foam plug. Snadwich the center ofyour foam with a couple pieces of 1/4 inch plywood and put in an eyebolt. with washers and nuts. Make the inside piece of plywood in the sahpe of the foam plug, but maybe an inch or two smaller on all sides. The part that faces your cockpit cna be 4 to 6 inches square or round. Drill a 1/4 inch hole in the plywood pieces, and also through the foam. Spin a nut on your eyebolt, almost up to the eye, add a washer, push the bolt through the small plywood, the foam, and the big plywood, then add a washer and another two nuts. Snug up the nuts so they cause the wood to gently compress the foam just a bit, then tighten the end nut so it jams agains the nut next to it, and locks them both in place. Grab the eyebolt to pull out the plug.

If you are thinking of making wood bulkheads you can use thin wood (4mm to 6mm or 1/4 inch plywood) and coat it with epoxy resin and glass cloth on both sides, or you can use wood that is a bit thicker, (say 3/8 to 1/2 inch) and just seal it with epoxy resin. Use your template to trace out a piece.

Unless you want to cut into the deck of your kayak for a hatch, you'll want to put a hatch in the bulkhead. Now is the time to do it. Once the hatch opening is cut and the hatch cover installed you open the hatch and you cna work on both sides of the bulkhead when you install it.

hope this helps

PGJ

Messages In This Thread

putting a bulk head in???
Jim P -- 6/13/2001, 5:53 pm
put a cork in it, so to speak :)
Paul G. Jacobson -- 6/13/2001, 9:03 pm