Sunday, September 28, 2014

Laminating the Stem

Installing the exterior stem (laminating in place) began yesterday morning with the first ply (the plies for the lamination are pine ripped to between 4 and 5mm. No indication of stress, strain, cracking or splitting during the dry fit, so I painted the faying surfaces with neat epoxy, spread a generous amount of thickened epoxy on the hull and screwed the pieces into place. Then we left for a family get-together.

First thing this morning, I removed the screws, sanded the first ply and repeated the process to install the second ply - staggering the seams to avoid/minimize creating a weak spot.

Late this afternoon, I repeated the process again - and nearly got ahead of myself. I installed the skeg piece (which is almost flat and under no stress at all) without doing a dry fit. No problem. But I caught myself before getting too far along installing the stem piece without a dry fit. Good thing, too, because during that dry fit that ply (which measured 5mm) took the curve without any apparent problem but began cracking as I drove in the last screw (which was no where near the crack). Before I knew it, the piece split, held for a second or two and then broke in two.

I quickly removed the pieces, checked the next piece (closer to 4mm than 5mm) and proceeded with a dry fit. This time there was no cracking, splitting or breaking and the installation went well.

Three plies installed, three to go...

I am using 1¼" sheet-rock screws and plywood pads (souvenirs of my Goat Island Skiff build) which worked really well to hold the ply to the curve of the bow without marring the surface of the ply. Because of the total length needed (about 12ft) for the stem and (foreward) skeg, two pieces of unequal length are used for each ply so the seams can be staggered.

While this is a bit of a tedious process - I can add a maximum of two plies a day - the results will be good. And, there is no lack of work to be done before the hull is ready to paint...

1 comment:

  1. Very nice result Bob. The planks veneer is beautiful also. I can see it clearly now. It is a dark brown wood ply. Everything look very neat. That will pay off in the end.