Archive for January, 2015


Monday, January 5th, 2015

For better or worse, all 5 bulkheads are installed. All things considered, things went pretty well. The lines seem fair. The bulkheads are vertical and evenly spread. Fillets have been applied. And if there are flaws, I believe subsequent operations will conceal them.

With the last bulkhead in place, the hull is noticeably stiffer. I read that Tad was surprised by how wobbly his hull was when first flipped. So was I. Now, even without the sheer strake supported, the distressing racking and bending is much reduced. I clamber into the boat with an easier mind.

Next up is what Tad calls the tanks. You might also term them the bench fronts. They are longitudinal plywood members, set vertically between bulkheads 1 and 5. Their purpose is two-fold: they support the side benches, and they work with the keel/keelson assembly to prevent the boat from bowing when it hits a wave.

The tanks are pieces that have long excited me. For whatever reason, they have always seemed a turning point in the construction process– the first piece of “interior” joinery. That’s rubbish, of course; the bulkheads were the first pieces. Then the case, and the case log. But I somehow got the tanks in my head as a turning point. And there they have remained. The other (and somewhat more logical) reason I’ve looked forward to the tanks is that they are the first piece of the boat that I knew in advance I would alter from Tad’s design. The first piece of creativity for me!!

In this photo, you can see that the openings in his benches are small, and all the same height. I’ve worked a fair bit in the NOLS Drascombe sailing program down in Baja California, and those boats have similar small bench-front openings. I’ve wrestled lines and sails and duffels in and out of them in a hurry many times, and I’ve been frustrated every time. I’ve also torn expensive bags in the process. I decided early on that I wanted big openings, and that I wanted the openings to follow the shape of the boat.

This turned out to be a dubious aesthetic decision, because I later decided to alter the floor shape from Tad’s design, too. But I didn’t know I would do so at the time. So we’ll proceed with similar naivete.

The tanks, then. Essentially another plank in many ways, but with the added complication that they are partially riven by three bulkheads along their length. I couldn’t figure out how I was going to fabricate them– build them in pieces, with butt glue joints at the bulkheads? Build them with scarfs joints, and glue up the pieces in place? or build the whole assembly outside the boat, and then somehow finagle it into place.

I had several beers while deciding. Then I left the whole question for a couple of weeks. Then I drank some more beers, and decided to pattern out the whole thing and see if I could remove it in one piece. I reasoned (sort of correctly, it turned out) that if I could get the whole pattern out without breaking it, I could maybe get the whole piece in without breaking it.


IMG_2644 (1)So I patterned out a side (the mother of all patterns. It was described by a friend as a horrible 5 year-old’s art project on steroids), and gingerly prised it out in one piece. At this point, I decided to construct the whole thing outside, and then put it in the boat as one. I decided against the butt-joint option because I couldn’t work out in my head how I was going to achieve fair joints at each bulkhead– seemed like whatever I did, I would end up with a sharp angle that would require lots of epoxy filler and lots of sanding. The scarf joint glue-up-in-place option I dismissed due to painful memories of planking.

I’ve come a long way in my comfort with epoxy since first I started this project. Most notably, I’ve come to appreciate its tremendous ability to fill gaps. I knew it could do so, of course, but I didn’t KNOW it. now I do. So as i decided on the all at once option, I was aware of — and comfortable with — the idea of trimming the tank around each bulkhead enough to get the thing in, and then filling the resulting gap with epoxy. And that’s what I ended up doing. Because I don’t plan to put any sort of hatches on the lockers, I also put a nice fat round over on all the edges, and cut limber holes along the bottom edge to allow drainage into the bilge.

I decided against trying to keep the tanks watertight because a shipwright I once worked for told me (in a charming Irish brogue), “No matter what you do, water WILL get into the boat. Don’t fight it– it’s just going to happen. Your job is to give it a place to go.” Smart man. He said that in reference to a 100-ft schooner. Doubly true for a daysailer. I’ll keep things secured in the cubbies with friction and bungee cords. Less to break, anyway.

After all the head scratching, things went together OK. I didn’t take enough measurements in the forward part of the tank footing, however, and had to dust off my trig to figure out how much bigger than my pattern to cut the inboard edge to get the angle I needed (which, of course, I realized once I had the gigantic and delicate pattern out of the boat, and didn’t want to put it back in).

IMG_2655There’s a lesson I’ll keep with me: with this sort of a project, it’s not about measuring twice and cutting once. It’s about measuring twice, and then taking the dog for a walk (or closing your eyes, or whatever helps you meditate) and visualizing each step of the cutting process, and how the piece will sit in the boat in relation to your pattern. Then go back to the boat, and measure the thing you didn’t even think about measuring before.

Then cut.

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Monday, January 5th, 2015

This whole plywood boat building thing has a bunch of advantages. Clearly, the biggest is the ability to construct a hull out of four strakes, rather than 20, But there are others, and the biggest of those is the ease of creating bulkheads. Ratty, like most other boats, gains strength from a series of transverse bulkeads. These help maintain the proper shape of the hull, resist racking, and also (conveniently) serve as the basis for benches and other internal furniture. Ratty has 5 of them.

Numbers 1 and 5 are solid, at least for now, and will form the footing for the foredeck, and whatever the dinghy equivalent of a poopdeck is.  Later on, that after bulkhead will also serve as the mount for the engine.  Numbers 2, 3, and 4 have big holes in the middle, and will support  (and be stiffened by) the rowing thwarts. The big holes in the middle will eventually have floorboards running through them.

As I’ve written previously, I put bulkheads 1 & 2, and 4 & 5, in as soon as I could after I flipped the boat. Then I procrastinated putting  the center bulkhead in for months. It’s bifurcated by the centerboard trunk, and I figured fitting its 2 halves would be a pain in the butt. It was.

In order to fit that center bulkhead, I had first to fit the centerboard trunk. The trunk is actually mortised into the keelson, and then sandwiched between two bits of wood called case logs. The bulkhead pieces serve to keep the trunk plumb, and the whole structure is a bit complex. Stupidly, I decided to glue the whole structure – trunk, caselogs, and bulkhead – up at once. Next time I won’t. I used epoxy hardener that began to kick too quickly, and found myself racing the clock. In future, I’d register the bulkheads in place (I’ve been using hot glue to “chock” bits of plywood against the workpiece for this purpose, and it seems to work quite well), then saran wrap any surface I don’t want glue on, glue the trunk up, remove the bulkheads, and then glue them in place using the trunk as a guide.

Learning. Yay.


This photo shows the assembly dry fit. the “chocks” of plywood are visible on the hull. Getting things lined up just so was difficult in the extreme, and I didn’t end up getting it quite right. (It’ll work, and be invisible). That 2×4 over the top of the boat is my level stick– I took measurements  along the flat top of the bulkhead to make sure things were level from port to starboard.





Post glue-up (and beginning to lay out the “tanks”).  Impossible to see from his — or any– photo, but the bottoms of the 2 bulkhead halves did not end up quite in the same place fore-and-aft– one is a bit behin the other. A matter of a half-inch or so. But once the thwart is laid on top, it’ll be impossible to see. Also, the centerboard case assembly warps toward starboard a little at the front end. The case top and the thwart on #3 will fix that.

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