Test Stitching

The bulkheads have been laid out, cut and glassed on both sides. The first 4x20 panel has been joined, the side panels laid out and cut. They have not been glassed yet. That happens after the test stitch.

Because of the extra opportunity for errors, what with all the scaling and the hand layout, I was a bit more cautious than usual about test fitting the bits together. Here I wanted to make sure that the boat had the same hull shape as Bolger's original design with no unfairness caused by scaling errors. This was the first opportunity to see if designing to a 1/8 inch tolerance was good enough to generate a fair shape. I also wanted to make sure that there were sufficient stitch holes to correctly hold the boat's shape (there were only 32 holes total).

Click on any image below for a larger view

First test assembly

The ends of the hull panels are stitched together. Bulkheads A, C, D and E are stitched into place. Mold B is not installed yet. The hull is 1/4 inch BS1088 okoume. The bulkheads are 3/8 inch BS1088 okoume covered on both sides with 4 ounce woven glass. Each bulkhead is stitched only at the shear and bottom. The shear line stitch holes will be covered by the rubrails, the bottom holes will be covered by the graphite/epoxy coating on the bottom. The only exposed stitch holes will be at the center of the bow and stern.

On the left are the unjoined plywood pieces, with their pre-cut puzzle joint fingers clearly visible.

Future cockpit

Bulkhead D in the foreground is the back of the cockpit. The solid bulkhead C is the front. The open bulkheads form a 2-inch stiffener for all the surfaces they contact. Once they are taped in place, they will form a continuous T-beam around the inside of the boat.

A set of puzzle joints is visible near bulkhead D. Note how the curve of the side remains fair, even when passing through the joint on the left side.

Future hold

Here's bulkhead A and the hold. Another puzzle joint is also visible, as is the future location of mold B. The spring clamps keep the hull from sliding off the sawhorse, if bumped.

Future rudder compartment

Looking back from the cockpit to the stern showing bulkhead D again, as well as bulkhead E. Bulkhead E forms an odd little triangle compartment that I'll have to try and find some use for. It'll be airtight and watertight, wih no openings.

There's yet another view of a puzzle joint. Also visible is an edge-view of the plywood. Note the 5 plies in only 1/4 inch thickness. The odd speckling in on the upper right corner of bulkhead D is the unfilled weave of the glass catching the flash from the camera.

Pre-cut puzzle joint

As strong, smooth and flexible as a scarf joint, but faster to assemble. Cut for you on a CNC machine by the good folks at Chesapeake Light Craft , with a fit tight enough that even dry you can pick up up the pieces (carefully!) as a unit.

Side view

The shear curve has formed up nicely, the lines are fair and match Bolger's original and everything is holding together. Time to take it all apart, glass the inside of the hull panels and put it back together again for real.

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