The time finally came to cut a hole in the bottom of my boat! A big long slot in the keelson was required to accomadate the centre board. Brian came along to assist, which was quite fortunate as it would be quite tiresome hopping from the topside of the boat to inside the hull to position and clamp the trunk in place.
We made a template out of hardboard from the top of the trunk and laid this onto the outer side of the keelson, and drew out where the holes were needed for the trunk posts. Armed with a 35mm hole saw, I cut 3 holes in the keelson and joined the middle and end hole with a jig saw, for the slot. This allowed us to use pipe clamps to hold the trunk in place. Then we secured the trunk with #14 -3" screws and took away the clamps so that I could run a flush trim router to square off the centre board slot in the keelson, taking a line from the inside of the trunk slot. This worked really well and ensured a gap free perfectly alignment between the trunk and the keelson. Some final spiling of the trunk logs was required and subsequent finer shaving off the top of the trunk. This resulted in a gap free fit and dead square alignment.
Seating the large 3" silicon bronze screws was a bit more troublesome - as they had Frearson (Reed & Prince) heads and the largest bit I had, a #2, did not have sufficient purchase in the screw head, such that I had to cut straight slots in two of the screws to drive them home. It is surprising how large a pilot hole is required to get these big screws home into hardwood. Even with the three pipe clamps in place, the screws created further squeeze out of epoxy which was satisfying - evidence that they were doing their job.
Once the epoxy had set, I removed the clamps this morning and re-checked alignment - measuring top of the trunk from each sheer plank to confirm symmetry. It was rock solid and within 1 mm from sheer to sheer - all told a satisfactory result for the first time wooden boat builder!
So next stage was to cut out the centre board slot in the keel and glue and screw this down on top of the keelson with 48 x 1 1/4" SB screws. Similarly, I cleaned out the slot in the keel with the flush trim router which ensured that all 3 slots (trunk, keelson and keel) were in perfect alignment.
As these nights are getting cold - forecast -3 deg celcius tonight, I have an electric blanket covering the keel and two small radiators running underneath the hull - should keep her nice and warm for the night.
Tomorrow - hope to start cutting out deadwood for the keel and attaching the outer stem and forefoot keel filler/ There are quite a number of different components making up the "keel" of this boat which initially was a world of confusion, but the fog is clearing and I now see the end in sight to having a finished underwater profile. Exciting!!
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