Together At Last!

Confession time: my first attempt at scarfing the side panels had to be aborted (didn't read the instructions for the resin and hardener dispenser pumps and ended up with non-setting toffee instead of thickened epoxy).

Another sheet of 6mm plywood was ordered, lofted, cut, and scarf jointed.

The two long and impossibly bendy panels were then taped together and lightly trimmed with a hand plane along the edges to fair them up and ensure that they were symmetrical. 

The bottom panel went better (scarfing) and was cut and edge planed very carefully so as not to mess up it's symmetry.

All mating edges were lightly bevelled, and after making  temporary bow and stern blocks, plus a temporary transom, it was time for the first trial fit!

The sides were screwed to the bow and stern blocks, then stood onto the bottom panel and gently opened up to check that they fitted. A couple of whiskers needed shaving off with the plane, but apart from that, they fitted really well.

The design I'm using is 'stitch and tape', but I wanted to be able to run an uninterrupted bead of epoxy fillet topped with two overlapping layers of 75mm glass tape along the whole length of the punt to get a really strong joint.

So instead of stitching the panels with wires which would have got in the way, I used strips of (3M) parcel tape on the outside edges. To my amazement it worked really well. The tape is easily strong enough to hold everything together and pulled the panel edges together for a really nice tight fit. Seriously chuffed!

Anyway, the punt was finally looking like a boat, though far too curvy without the inner frames. I can see why boats are referred to as 'She' with curves like that!

View from stern - parcel tape and a few screws holding it all together

View from the bow - not quite so sexy from this angle

Before applying the epoxy and tape, I stretched gaffer tape across the top edges at the frame positions, making each one the same width as the corresponding frame's top width measurements. I didn't want to 'set' those exaggerated curves into the hull, only to have to pull them in when fitting the frames - the leverage could possibly damage the seam joints, or even crack the very fragile ply.

Curing time when building with epoxy resin really adds to the build time, so where possible, I am laying-up 'wet' - starting with a layer of unthickened resin (to prime the plywood), then thickened epoxy fillet and glass tape/resin (main seems get two overlapping layers) all in one session.

Certainly saves time, but I've also read that the bonding between the layers is stronger this way. Doing the inside seams this way took me several hours (my first time), so although quicker than waiting for individual layers to cure, you do need a good clear time slot in your day.