Starting the second hull half

I know, been here, done that ...  But wait, before you tune out, read on for all of the wonderful new techniques we are trying out on this half.

Here is the start of planking the second hull half.  Upon first glance it may look remarkably similar to the start of planking the first half (I promise I didn't just repost the old photo).  But if you look closer, you might notice the screws are silver instead of black!  Amazing, I know.  Well, with the (black) drywall screws we were using, the wood clamps tended to form a divot in the foam when the screw head pushed through the wood.  To reduce the amount of filling we have to do, I am using lathe screws that have a broad pan head.  Since the lathe screws don't sink into the wood, there shouldn't be any damage to the foam aside from the screw hole.

The other change to our technique is that we are using a heat gun instead of the toaster oven for thermo-forming the foam planks.  The scalloping of the planks occurs when the planks are heated and bent into the tight bend.  The heat gun allows us to better control the amount of heat applied, as well as limiting it to local areas.  Most of the plank will bend to the form without heat.  Just the tight bend where the hull transitions from the side to the deck of the hull requires heating to prevent breaking.  After trying this on a few planks, I found the use of the heat gun results in a better final form in less time.  The unheated sections are very fair, so the final product should be superior.  There is still some scalloping where heat is applied, but I can reduce the distortion by minimizing the amount of heat applied.  The seams also stay very straight, so I shouldn't have to do too much trimming when I glue the planks together.  At the bow and stern ends where we get into compound curves, the seams need to be trimmed at top and bottom, but the middle then comes together nicely.  With the toaster oven, the edges tended to distort along the entire length of the seam, so we had to do more trimming.  So far, I prefer the heat gun for this thin (9.5 mm) foam core.  I can imagine the toaster oven would be better for thicker core material, or when more complex forming is required.

Hopefully we will finish the planking tomorrow and plan to laminate the inner surface next weekend.  Check back soon for updates.