I've got a lot of things going on at once at the moment and this photo shows most of them. On the port side of the boat (right side of the photo), I'm still applying and sanding epoxy fairing compound to prepare for planking. You can tell it hasn't been sanded yet because it turns from dark red-brown to white with sanding. (The color change has the added advantage of helping you to see low spots that aren't scraped by the sandpaper.*) On the starboard side, the fairing is finished and I'm starting to shape mahogany planks to fit into the hull.
The planks don't go in straight, but curve along their sides. That means each has to be individually shaped by hand on one side to fit snugly against its neighbor.
The planks go in at an angle to the layer of planks below. This makes the boat stronger by aligning the grain of the wood in a crisscross pattern.** It also means the planks don't need to bend as much to fit the shape of the hull. That's not a huge deal except for near the bow, where the planks need to bend in multiple directions.
The first plank can have straight edges on two sides. I made the other two using different techniques as an experiment. For one, I used a compass to scribe a line along the edge of the plank and then cut and sanded it to fit. For the other, I used a small brass violin maker's plane (barely visible in the photo) and did most of the work by eye, taking shavings here and there until I got a good fit.
Both methods took about the same amount of time, but I had more fun using the plane. It's good to know both ways of doing it work well because some of the shapes may be more difficult when I get closer to the bow. I have one more method I may try out on the next plank.
You probably noticed all the popsicle sticks stuck to the planks. I could say that it was a really hot day and I ate a lot of popsicles to stay cool. But actually they're tongue depressors and I am using them with a pin gun (an air-driven tool that shoots super-skinny headless nails) to temporarily hold the planks down as I shape each one. I'll need to take the planks off again before I can epoxy them in place. My as yet untested theory is that I will be able to break off the tongue depressors and easily remove the pins with a pair of pliers. (This is another technique I made up on my own, but doubt I am the first to think of it.)
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| Bostitch Pin Nailer |
I can't finish the job of patching the big hole in the mast step area until I install the planks. That's because the patch needs to go in on top of the new layer of planking.
The patch is almost complete. Below are a couple of photos of what it looks like. The first shows it from above with it temporarily in position. The second shows the underside of one end of the patch. Note how it is both layered and stepped. The dark lines are epoxy between each layer. I watched those lines carefully as I sanded the bottom of the patch into a triangular shape, trying to keep them relatively straight fore and aft. The final sanding to fit should remove those lines almost completely.
The patch is also curved fore and aft to match the shape of the hull. To get that arc, I cut out a piece of plywood in the shape of the boat's bottom (working off the original plans) and then laminated the patch together with epoxy and clamped it to the plywood mold. Here's a photo of what that looked like (and also happens to be a good illustration of why woodworkers often say that there is no such thing as having too many clamps):
Finally, when I cut out the piece of plywood for the laminating mold, the matching curve in the leftover piece was perfect for making center supports for the frame that the boat sits in. If you look again at the picture at the top of this post, you can see them peeking through the big hole. They are covered in plastic so they won't stick to the hull when I epoxy everything together.
*Even though you can see one of my Festool sanders in the photo, I did 95% of the fairing on the inside of the boat by hand with 60 grit sandpaper backed with a piece of wood. It's too easy (for me at least) to add new highs and lows into a fairing job with a power sander.
**This crisscross pattern was especially important in the past when the planks were glued together and varnished. The orientation helped keep the wood from expanding and contracting as it gained and lost moisture. Because wood doesn't move much along the direction of the grain, each plank would help hold the boards above and below it in place. This is less of an issue now with epoxy, which prevents moisture from getting into the wood at all. This is a topic I'll be coming back to in more detail and will discuss why epoxy can, under certain circumstances, make the problem worse.
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