P-2 STITCH AND GLUE SYSTEM
Welcome to the secrets of polyurethane and waterproof pva stitch and glue process.
The problem with using polyurethane glue for stitch and glue has always been the bubble effect coursed during the curing process, then the endless sanding to smooth and fair up.
Now using the P-2 system of stitch and glue it avoids the problem by using a fillet made from a polyurethane tube and glue gun and a fairing coat achieved by waterproof pva and toilet paper combo to leave a smooth finish.
With the polyurethane being the structural strength trusted below the waterline glue and the pva acting as a filler its the best of both worlds coming together. The pva eg Titebond 3 is not structural its propose is a fairing coat.
This is achieved by ,,,,,,,,,
Stitching your plywood panels together by plastic cable ties
Cutting the nozzle on a polyurethane glue tube as fat as you can with a 45 degree angle to fillet the panels with a glue gun, then cover area to be tapped in glue.
push x2 100gm fibreglass tape overlapped on to the polyurethane glue fillet and glue area
Lay x2 layers of toilet paper precut to cover just over the tape area, lightly press in place don't push down hard just lay on top and let the glue soak through.
Allow the polyurethane to cure fully as specified by manufacture. Then soak the toilet paper in waterproof pva-Titebond 3 then add 1 layer of 100gm fibreglass cloth and make sure the Titebond is saturated through the weave and allow to cure.
For filler use Waterproof glue and telc powder mix, mix to a consistency that will stay in place vertically if needed.
Once process has fully cured, waterproof glue spit coat with a roller-brush the hull inside and out.
This process if done correctly should leave your boat with minimal fairing to be done, because of the toilet paper acting as a filler over the top of the polyurethane glue tape and the pva providing a smooth finish fairing coat, its a one shot process, then using polyurethane glue being accepted as a below the waterline trusted glue to seal it, and acting as as a fast drying sealer to protect the boat, your in the water faster enjoying your boat.