Setting up the construction molds

In constructing Justine’s molds, I followed established procedure and cut the bottom of each mold in the plane of the construction baseline shown on the plans. With the baseline positioned near the barn floor, this placed the molds at a convenient working height for construction. As a first step in setting up the molds I needed to lay out the construction baseline in our barn.

I decided to make the baseline using long lengths of 1 x 2″ lumber that could be screwed to the barn floor and shimmed into position using opposing pieces of cedar shingles. My laser level was the ideal tool for positioning the baseline. The two photos below show what I did. I used about 21′ of 1 x 2 for my construction baseline as it would be needed over Justine’s entire length.

I set up my laser on a camera tripod on the ground just outside the barn door and adjusted its height and position to serve as a temporary construction baseline. I knew that the laser would make a perfectly straight and level beam of red light. I then began to secure a 1 x 2″ pine board to the barn floor, with its upper right edge (as seen here) positioned very carefully along the laser beam.
I used two cedar shingles with their wedges opposed underneath the 1 x 2 to adjust the height so that the laser beam just kissed the corner of the 1 x 2. Once in position, I used dry-wall screws to fasten through the 1 x 2 and shingles into the barn floor. The top of my laser level is visible just beyond the barn door.

Each of Justine’s molds needs to lie perpendicular to the construction baseline. I drew a very accurate perpendicular line about midway along the baseline, using the method I was taught in my high-school plane geometry class. Then I’d used a ruler and a compass. Now, I’d need a long compass and I made one up using  a small lumber off-cut fitted with trammel points. One of the trammels has a pointed end, and the other can hold a pencil. So I had an adjustable compass about 5′ long with which to draw the arcs to erect a perpendicular to the baseline.

The beam and trammel points served as a large compass.
Starting with a tick mark on the construction baseline, arcs are drawn on the baseline a few feet on each side, then longer arcs are drawn from centers where the first arcs intersect the baseline. These arcs intersect along the perpendicular to the baseline, drawn from the initial tick mark. I put a small pad approximately where the intersection would like, before drawing the intersecting arcs shown here.

With a straight and level baseline, and an accurate perpendicular reference line, I was ready to start fastening the molds in place. I began near the center of the boat with the mold at station 14. This mold was supported with diagonal bracing to keep it exactly vertical. All the other molds were secured in the vertical plane with battens that tied in to the mold at station 14.

Here molds 13-23 are set up in position on the barn floor. The diagonal bracing holds mold 14 in the proper vertical plane, and the other molds are secured to it with battens to achieve a uniform 9 3/4″ spacing between stations. Shingle shims under the butts of each mold bring the mold to the correct height and with its cross spall level .
With the construction molds in position, you can really visualize the there-dimensional shape of the hull! The long battens hold each of the molds in the proper vertical plane. You can see that Justine did a good job of taking up much of the floor space in our barn…

The photo above was taken on September 15, 2008. I began construction of the molds in the fall of 2006. The project’s pace was slow. I was working full-time in Boston, and building Justine in Georgetown, ME, a three-hour drive away. So much of the construction work was done on long weekends, holidays, and vacations. I didn’t retire and move to Maine until 2013.