Day 12

5/21/2012

It's time to permanently join the deck and the hull together.  I will be using a hybrid method employing both copper wire stitches and shrink wrap.  

Step one in the process is lay the deck onto the hull but keep them apart using scrap wood for stringers.  


It all starts with a single stitch at the bow:

Then, working toward the stern, additional stitches are added and stringers are removed.  Notice how loose the stitches are.  Once all of them were in place I came back and tighten them one by one, alternating sides.

As the stitches were tightened, I injected epoxy thickened with silica powder between the deck and the hull at the bow and stern to glue them together since it will be nearly impossible to reach them from the inside after the boat is closed up.

Once all the stitches were tightened and the stringers removed, I wrapped areas that needed additional tightening with shrink wrap.  I also used a steel paint scraper as a lever to align the panels where needed.  Then the boat was turned on its side so the new joint could be tack welded with epoxy thickened with silica powder.  Note the large tack welds in the second picture below.  There is a lot of strain pulling on the seam and I do not want things to fly apart when the stitches and shrink wrap are removed.


After one side sets up, the boat was flipped over and the opposite side received its tack welds.

While the tack welds were drying, I decided to go ahead and lay up the coaming.  It will be permanently attached later (after glassing the deck), but with care this is a good time to lay it up and clamp it down so it takes the shape of the cockpit opening.  This is a variation of the CLC manual, but building the coaming so that it can be remove will make it much easier to clean up the excess glue and allow me to add a thick epoxy fillet under the coaming ring for added strength. 

First I covered the entire cockpit opening with plastic.  Then I stretched a string from the tip of the bow to the center of the stern to find the centerline of the boat.

The coaming consists of 5 parts, 4 plywood spacers and a coaming ring.  The mating surfaces of the spacers are slathered in epoxy thickened with silica powder, then laid up in layers and finally topped off with the coaming ring.  Then everything is clamped down in place around the cockpit.  Not the wood spacers under the clamps, which protect the coaming from being dented by the clamps and force the clamps to exert more pressure on the pieces being glued.

This is every clamp I have in the shop.


Comments