STITCHING & RAISING BOTTOM PANELS
February 14, 2021
Putting the Stitch in Stitch-and-Glue
With our hull panels complete we can now introduce the stitching component of stitch-and-glue boat building.
The stitches on our boat are literally just that: lengths of steel wire used to temporarily hold the seams of the hull panels together and in place on the bulkheads. The stitches remain in place until the components are joined with tabs (small 3" by 1" pieces) of fiberglass set in epoxy. Once the hull panels are tabbed together – locking them in their final position – the stitches are removed and the seams are reinforced by a strong laminate of biaxial fiberglass cloth set in epoxy – putting the glue in stitch-and-glue.
Thicker gauged wire was used to hold the panels together at the bow and stern where resistance to bending was greatest. A pair of end-cutting nipper pliers were the best tool for twisting the wires to the desired tension.
The panels that make up the bottom of the hull are the first to be stitched together. To start, we positioned the two panels so one was on top of the other, inside face to inside face, and drilled holes along the length of what will be the keel edge (very bottom seam) of the hull. Six-inch segments of steel wire (the stitches) were threaded through the holes and twisted with enough tension so that they hold the panels in place along their chamfered edges when they are opened up and placed on the bulkheads. The holes are spaced six inches apart along the length of the panels except for at the bow and stern where they increase in density to one every two inches. This is because the shape of the boat is more complex at the bow and the stern, especially the compound curves of the bottom panels near the bow. These sharp curves require more stitches to hold them in place for two reasons: to get the necessary torque to pull the panels together; and to help keep a fair, smooth curve along those edges with the most resistance to bending.