A Shipwright in Training

In order to get that joke, you need to know that IYRS is pronounced “Iris” and Spiling is pronounced the same as Smiling but without the M.

Any joke you need to explain is not a good joke.

If you’ve tried to access this site recently you’ve probably gotten a number of errors. It seems that bad people were trying to hack into my account and caused some havoc. Luckily the folks who host this site are super-wonderful and blocked them. I’ve now updated the software on my end to make sure they’re blocked for the foreseeable future.

Ok, here we go. Words of the day: Spiling, and it’s counterpart, Despiling. Spiling is a fancy way of saying “copying,” but it refers specifically to copying the shapes of planks. You see, planks are nice smooth things that wrap around a boat, and in order to make them functional as well as pretty, you need to have a way of making them fit tightly as they bend and curve around. When you spile a plank, you copy the plank’s shape onto a thin strip of wood called a spiling batten. When you Despile, you take that information from the spiling batten and transfer it to your new plank. The thing that makes this soooo coool is that you’re taking a shape that curves throughout a 3-D space and transferring it to a flat plank that will fit when it too curves through space. Nifty, yes?

Here are 2 pictures showing the spiling process. First, you take the pointy end of your compass and put it up against one edge that your plank will eventually butt up to. Then you trace a little arc onto your spiling batten that you’ve tacked onto the boat more or less where the plank will go. Here’s the arc being traced from the rabbet.

And here’s a 2nd arc being traced from where we know the bottom edge of the plank should lie. How do we know where the bottom of the plank should lie? Boatbuilder’s secret. If I told you, I’d have to take you sailing.

Now look what we’ve got: a couple of arcs. If you remember your geometry, you’ll recall that if I were to take the pointy part of my compass and place it on one end of an arc and make another arc with the pencil, and then put the pointy part on another part of that first arc and make a 2nd little arc that crosses the arc I just made, the resulting X would be the center of the first arc. Why do we care about this? Because when we made our first arcs on the spiling batten, the centers of those arcs were exactly at the edge of the planks we want to make. When we Despile, we’ll recreate those points all along our new plank, connect the points with a fair line, and voila! we’ve got the pattern for a new plank.

Here’s a little shot of transferring points from the spiling batten onto planking stock.

You can see a little V at the bottom of the batten and an X at the top of the batten to the right. I’m just about to make an X by crossing an arc moving from left to right. The next step is to connect up all those X’s. And this is what you get traced along your planking stock:

See how the X’s are connected by the line going left to right? That’s the plank edge. The twin vertical lines mark where the frames are on the boat. They’re numbered 1-23 (the number of frames in the boat) and are used to locate the plank once it’s steamed and ready to slap onto the boat.
Once you’ve got your plank traced out it’s time to cut it out with a circular saw. Actually, it’s time for Kevin to do that.

As he cut, the tension in the board released as indicated by how open the saw cut is following him.

That’s the board’s way of saying, “Man, I’ve been tense and now I’m feeling relieved!” It’s nice to have relieved boards. The bad thing is that if the board relaxes too much, it will change its curve, which means that the nice little curve that we Despiled onto it will be wonky and may need to be forced into position on the boat when it’s planking time.

After rough cutting with the circular saw, we plane the plank down to our line.

This makes lots of nice shavings. The goal is to have a smooth, fair curve.

That’s pretty fair.

When all is said and done, you get a couple of garboards (the planks that butt up to the keel) that pretty closely match the shape of the keel.

Tomorrow we’ll cook ‘em and try to bend them onto the boat without them shattering. Yes, they often split, as Ben and Scott found out today with Both of their garboards. When you take the better part of the day making a plank, you really really get pissed off when they break on you.

This entry was posted on Tuesday, November 28th, 2006 at 9:37 pm and is filed under Classes. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.