Grapeview Point Boat Works

81 E Grapeview Point Rd + Allyn, WA 98524 + 360-277-9015 + boat_works@yahoo.com

Building a Glued Lapstrake Caledonia Yawl

Page 13: Thwart knee pattern and tiller arm

Thwart knee pattern
Thwart knee pattern

We're getting down to the little bits that are interesting to make, but take more time than seems probable.

We have made a few patterns for the wood thwart knees, and finally settled on a shape that doesn't intrude quite as much as Iain's, but still has the required strength. By laminating these parts instead of making them one-piece they will be much stronger (since the grain direction is optimal throughout the length of the part), and thus can be shorter than the style he has drawn.

The tiller arm and wedge
The tiller arm and wedge

We milled the laminates and made a simple bending form. Each knee will have about ten laminations in order to make the tight bend required.

The tiller arm and wedge are shaped and fitted. The wedge will eventually have a lanyard to prevent loss. You can see the rudder lift line exiting the rudder head. The downhaul will exit the other hole. A cleat on the forward face of the rudder head, just below the holes will secure the control lines.

The tiller arm
The tiller arm

We are also designing the rudder hardware so I can get Tom Kughler, the fabricator, started on that part of the project.

The benches are shaped, bent and fitted. Friday we made the bench knees, and today we glued trim on their inboard faces to increase their apparent width. Looks nice! The thwarts, side benches, and centerboard trunk caps will all be removable for maintenance and painting. The mast partners will be screwed and glued in place permanently.

The bench knee in place
The bench knee in place

Our spruce supplier didn't have what we needed in 20' lengths, but they are receiving more logs from Alaska, and will have the 8/4 vertical grain spar grade Sitka spruce for us in two weeks. That won't hold us up.



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