Kayak plans and cutting the forms

The template was completed with valuable lessons learnt about how the plans fit onto the forms and the form's angle as the distance from the bow changes. This also impacts the thickness of the spot glue between the strip and the form.

First, print out the PDF plan on full-size sheets of paper. For the microBootlegger, this requires 8 sheets. A plan printing shop or Office Works can handle this for you. Next, cut out the outlines, leaving a good paper border around each shape. I drew a red pencil line as my cutting guide. Arrange these pieces on a large sheet of plywood or MDF board to minimise material waste. Apply spray contact adhesive to both the paper and the board, then gently lay the plan pieces down, smoothing each one as you place it.

Plan glued to form board

I recommend using a jigsaw with a suitable wood blade to cut these forms from the board, following your red line. Needless to say, my 30-year-old Metabo jigsaw finally succumbed to metal fatigue—snapping the plunger in the process. Fortunately, I had a backup, and the work continued.

Cutting forms to shape

Next, remove the hole for the strongback in each form. This plan specifies a 2-by-4-inch hole in each form to indicate its alignment on the strongback. There are multiple strongback designs for kayak and canoe building. Generally, canoe builders use an external strongback since they don't need to turn the boat over, whereas kayaks require flipping to complete the deck. An internal strongback allows you to turn the entire building unit over when transitioning from hull to deck.

Router jig

Removing the forms and strongback after completing both sides is straightforward. There's a part line in the strip planking where you don't glue the hull strip to the deck strip. Once completed, a bit of careful separation reveals the strongback and forms.

Cut forms Bow and stern

I chose an aluminium 2x4 box beam as the strongback and sought a second-hand option in Canberra. An Italian builder completing a large house was selling excess materials. After intense negotiation, I acquired a 6.2-meter aluminium box beam and a crate of rusty G-clamps for half the price of a new beam.

To cut the beam hole in each form, I used a jig screwed to the form and a table router to create a perfect 2x4 rectangle in the correct position. Using the band saw, I cut around the final plan line—though not without challenges. The bow and stern's sharp angles mean the first few forms, slightly over one inch (73mm) thick, have varying angles from the paper plan on the front to the form's back.

The first form widens at the back, requiring precise cutting with allowance at the aft section. The angle of change isn't consistent because the hull's top is straight while the waterline side shows the most significant angle variation.

Unshaped forms on aluminium strongback

After cutting, I used my rotating sander (built during the Malua construction) to sand the forms to the exact shape. The next step involves fitting the forms onto the strongback in the precise position and squaring them to the centre line.

To be continued in the next post.