Adventures with lapstrakes

Since last time I cut and scarfed all the rest of the long pieces: strakes 2, 3 and 4.  It involved measuring, drawing and cutting two copies each of two parts (fore and aft) of three strakes, or twelve in total.  The design program provided coordinates, which I manipulated on Excel.  When the time came to scarf and glue, I had to be extra careful not to join anything the wrong way.  I found that laying the pieces on top of each other, staggered in 2-inch steps, then using a belt sander, worked very well.  Provided, that is, that the sanding belt was coarse and very new--it's amazing how quickly the grit gets dull while scarfing.

I first beveled the edges of the garboards (strake 1 or bottom piece) to the correct angle. then nailed and glued strake 2, lapped over the beveled edge of the previous one.  Nailing along the lapped edge is a lot easier with something heavy, smooth and hard held behind it--a second person would have been good doing that but I don't have a helper, so I tap in the nails enough for them to stand up, then hold the clenching iron against the back and nail them in.  I have been filling the excess overlap gap with filleting compound (epoxy and wood four).  Here's what the boat looks like with the second strake on.  There is still trimming, sanding and nail setting/puttying to do, but that can wait.

After scarfing what I thought was strake 3, I tried it on for size, but it didn't fit.  Panicked, I concluded that I had glued the fore and aft pieces upside down--the curve of the edges looked that way.  I looked for ways to cut through the scarf, but it was clearly too strong: I would have to cut the long pieces in half and butt-join them the right way.  Before taking that drastic step, I tried to calm down and double-check.  Using the Pythagorean theorem again, I calculated what the width was supposed to be at different positions and measured the pieces.

As it turns out, the pieces I had scarfed together were strake 4, the last, top strake (at the sheer).  The pieces of strake 3 were still leaning against the wall, unscarfed.  Why I never actually labeled them and relied instead on a vague idea (strake 3 in this corner, strake 4 in that one) I cannot explain to my satisfaction, but I made a mental note for next time (and so should you).  Strakes 3 and 4 were too similar.  I had labeled fore and aft, top and bottom, but not 3 and 4.  I expect it's even easier to mess up with traditional, narrow lapstrakes, as opposed to the 4-per-side wide ones I used.

So there you have it.  Strake 3 fore and aft halves are glued together and curing as I write, and will go on next.

Until then, keep checking 176inches.

boatbuilder