This is the aft bulkhead along with a nice assortment of my clamps.
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Then I did bulkhead number 3 the lower cabin bulkhead.
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In the lower cabin bulkhead you can see a slot on the left side. This slot will be enlarged later to accommodate the the center board trunk. The trickiest part of installing a bulkhead is getting the right shape to fit. The aft bulkheads have fairly straight lines so it is possible to take several measurements and come up with a close approximation of the required shape.
The forward bulkhead is a bit more complex. I used a different strategy.
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I used a plumb bob to establish a line where the bulkhead will meet the hull.
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Sally is checking out the pattern I have made. I installed a scrap piece of plywood in the location for bulkhead number 1. Then I stapled little scraps of plywood like fingers touching all the important points around the perimeter and some inbetween.
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OK now what?
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How did that cat cat up there without altering the precise position of any of my indicator strips?
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I made a mark at the tip of each indicator strip, connected with some fair lines and cut out with a jig saw.