A Shipwright in Training

Yes, I still like school. Despite the fact that it will soon poisen me and I will die a truly horrible death, it was fun while it lasted. More on that later.

We spent Monday in the drafting room making very detailed, scale drawings of the beetle cats that we lofted a few weeks ago. We used the information from that lofting to make these drawings, and it’s here that we can get a good idea of how precise we’ve been (or not). It’s careful, slow work, and the thickness of a pencil line matters in these drawings. A lot of folks didn’t like it, but I did. Time flew by and it took a lot of concentration.
Now we’re back in the shop, and a lot of parts have been taking shape these past few days. We pulled the stem from the glue up. Yug. Hard hard epoxy. (by the way, this is someone else’s stem, we were a bit less liberal with our glue). That’s one ugly stem.

15 minutes of belt sanding gets the bulk of the epoxy off the edges. Flatten the side of this thing on the jointer, use the thickness planer to thin it down to 1 1/2″ thick, and you’ve got a nice little stem, ready for final shaping. You take a template, trace the outline on your stem, band saw it to rough shape, and then plane, spokeshave, and scrape it to your line.  Easy.

Here’s our stem, all cut out pretty like. You can see the template below it. The template also has lines on it indicating the rabbet and bearding lines. These lines tell you where to cut the all-important rabbet (scarey music here). The rabbet is a v-shaped groove that you carve into the stem and keel. The planks fit into this groove, so you have to make your rabbet just exactly right so that the planks fit perfectly. If they don’t, you get a leaky boat. The bearding line is the inside edge of this v-shaped groove, the rabbet line is the outside edge. In the center of these two lines is the apex of the v, and it’s called the…

wait for it…

middle line.

To make a nice fair curve, we lightly tap in nails along the rabbet and bearding lines through the template and into our stem, take the template off, and then re-nail through those little holes. Then we put a batten (any flexible strip… here it’s the thin clear plastic rod off to the right) up against our nails, draw a pencil line along it, and viola, a nice smooth line. The blue ducks (actually they look like whales) are made of lead and they help hold the batten down while we draw the lines. you can see our stem has the rabbet and bearding lines drawn on it.

Drawing the middle line is the final step before cutting the awesomely important rabbet. Here’s Kevin working out the proper angles to do this.

It’s easy once you know what’s up, but it’s hard to describe it in words.

In the meantime, we’ve traced out a centerboard from marine plywood, roughed the shape on the bandsaw and planed, spokeshaved, and rasped it to the proper shape.

Next step is to cut a 5″ hole in it, and fill the hole with molten lead. That was a ton of fun. We melted the lead out back, clamped a sacrificial scrap of plywood underneath the hole to make a little pool, and poured away.

Yes, it scorches the wood. It’s wild.

Now we’ve got this nifty plug of lead in our keel to keep it from floating up when we’re sailing along. But, we put a healthy plug in, enough to rise proud of the surface a bit. The best way to smooth that down, is with your hand plane.

Yes, you can plane lead. It’s quite soft. And really poisonous. That’s why it’s important to eat those little shards of lead so that you can develop a tolerance and keep the people from the EPA from asking inconvenient questions about where you walk after planing lead, what sort of breathing protection you were wearing, whether or not you washed your hands afterwards and if so, where you put the rinse water… all that sort of stuff. Word to the wise, taco sauce really helps the lead go down smooth.

We also cut out our skeg (not pictured) and our sternpost (one of the main thing that holds up the transom).

Onward onward. Tomorrow we cut the dread rabbet. Each student cuts one side of the stem rabbet. That way, you’ve no one to blame but yourself if your planks don’t fit quite right on that side. Kevin and I have agreed that I’ll go first.  Heaven guide my mortal, shaking, lead-poisened hand.

This has been a busy week, hence the lack of blogging.
I still love school.
This week we got partners, and my buddy Kevin and I are now working on a little beetle cat together. Here she is as we got her. You can see where a previous owner went to the trouble to build a new stem and added on one plank on the port side, and then just stopped. Go figure.

You can see lots of rust damage from years of water getting through little cracks in the paint and destroying the iron fastenings.

So, the first order of business was to take off the deck and deck supports so that we could flip the boat upside down on top of molds that will hold the boat in the proper shape as we take it apart and re-assemble it with new bits. Here’s Kevin taking off the decking boards.

This is a view of the top edge of the sheer (top plank). With the decking removed, you can see where water infiltrated through the fastener holes and rusted out. I also think they used fasteners that were too large and didn’t predrill the holes so they split the planking where they fastened into it.

Deck all removed, and half of the centerboard trunk removed, revealing the centerboard (deep blue).

We set up the molds precisely on a grid that we’ve drawn on the floor, and then we brace the hell out of them. After all, we’re going to be plopping a boat on top of them, bending wood over them, and climbing on top of them. They need to be rock solid. Here’s Jason setting up his stations. These molds define the shape of the hull and we’ll be pulling the old boat down onto them to bring it back to original design shape.

And here’s our boat on the molds.

We screw the boat to the molds to hold it solidly, and then begin removing its spine: garboards, keel, stem, sternpost, and eventually the transom. Here’s Kevin taking out garboards (the planks that butt up against the keel).

You can see the cotton caulking that went in between the garboard and keel. The little light squares of wood act as washers to keep the screws from pulling through the plank when she screw it down to the molds.

Keel and stem removed.

Next, we fashion a new keel from 1 1/2″ oak and cut a rabbet (the slots you see on the left and right sides). We use a template to get the correct keel shape, and use a circular saw and hand planes to cut it out to the exact shape.

Then we put it in a steam box for an hour and a half (1 hr / inch thickness is the rule) to soften it up.

Then we clamp it to a long curved mold to give it the curve we want. Hot hot hot!!!

While that’s cooling down, we cut strips of mahogany, stack them up so that steam can get to all surfaces, and steam them as well.

When they come out of the steamer box, we bend them to shape on a form as well. Now, it’s starting to look like a new stem.

Once they’ve cooled and hold their shape, we epoxy them together in another form. This second form holds the laminates in the same shape as the first form, but laying the strips sideways on the table allows us to stack them more precisely. We’ve covered this bench with plastic, screwed in angle irons to the table along the edge of a pattern, and then we clamp the wet, glued layers up to the form. In a day we’ll take it off, clean up the glue and have ourselves a rough stem to work with.

We’re using mahogany for the stem rather than oak (original) because oak moves too much as it gets wet and dries. The result is that almost every beetle cat we get has delaminated stems. Mahogany is far more stable and will last much longer. For instance, here’s the original stem from this boat. It’s no surprise that the stem was one of the things the previous owner replaced.

And here’s the new keel clamped to the molds. This is what we’ll rebuild the boat around.  The combination of stem, keel, and transom constitute the spine of a boat.

Not bad for a week’s work!

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