The Arctic Tern Project

Volume No. 1 Issue No. 9 December 19, 2004

Major Bulkheads Fitted and Pinned

Well, it’s taken some time but the major athwartships bulkheads have been fitted and pinned in place.

A few words about the methods employed are in order. Although I made templates for each bulkhead these were only used to test my measurements and make minor adjustments. Each bulkhead was laid out direct from measurements (sometimes adjusted based on the fit of the template). It was important to ensure that each bulkhead was exactly symmetrical so tracing from a pattern was not practical.

After the bulkhead is cut out it is placed in the boat and checked for fit. Usually some minor adjustments with a hand-plane are required at this point to get a good fit. To make sure the bulkhead is at right angles to the centerline of the boat I measure diagonally back from the stem on each side and confirm that these measurements are identical.

Once this is confirmed I pin the top of the bulkhead on each side.

Then I put the level on it and make sure it is exactly vertical.

Once I’ve confirmed this I pin the bottom of the bulkhead.

Next I make sure the bulkhead is lined up exactly in the center of the boat. I achieve this in two ways. Firstly, there is a centerline marked on each bulkhead and I make sure this lines up with the center of the keel seem. Secondly, I measure from the center of the keel seem to the sheer at the bulkhead on each side and make sure this measurement is identical on each side.

Once this is confirmed I pin the underneath of the bulkhead. This prevents it from shifting side-to-side.

Portions of certain bulkheads have been left in temporarily in order to assist in lining them up correctly and providing additional stiffness for when the boat is rolled over. The following pictures show a cross piece left in the forward and aft cabin bulkheads for this purpose. The pieces will be cut out later.

The Next Steps

The next steps are to mark out and cut the notches for the sheer clamp. Then each bulkhead will be removed from the boat and coated with two layers of epoxy. After this they will be reinstalled using epoxy as glue.