Progress Through August 2010
Posted By Tom Daniels on October 27, 2010
The crew has been cutting futtocks for a while now. As you may recall, futtocks are curved parts that are fastened together to form frames.
After being cut and beveled to fit the patterns from the lofting, the futtocks are assembled upstairs on the lofting platform.
The individual futtocks are held in position with clamps, drilled, and then finally pinned together with trunnels.
The drill for this process is big enough to get its own stand.
Definitely not your everyday basement shop drill. No sir.
The frames are then moved off of the lofting platform, and a deck beam is fastened in place.
For those of you who are boat builders, this step may seem unusual. The deck beams are usually installed after all of the frames are in place. The crew decided that they were confident enough of their drawings to go ahead and attach them at this stage of construction. This method has the additional benefit of providing a built-in lifting point for the frame assembly during installation. Two other diagonal braces are temporarily attached to the frames to help keep everything stiff and aligned.
The frame / deck beam assembly is then craned over to the boat and bolted in place.
Here, you can see the four different futtocks that are making up one full frame. I’ve (crudely) outlined each in a different color here.
One of the advantages of working with really good drawings and patterns is that when you assemble things, they fit just right. Here is the base of the installed frame where it intersects with the keel rabbet. The little stick shows how the angle of the frame flows right into the rabbet.
This also gives you an idea as to how thick the planking will be. The planking goes from the inside face of the rabbet (also called the backrabbet) to the outer face of the keel. That corner where the base of the rabbet meets the outer face of the keel is called the rabbet line, and it’s this line that you’re looking at if you see a rabbet drawn in a boat’s plans.
Here’s another view with the side of a phantom plank drawn in to illustrate how it will lie against the frame and settle in the rabbet.
The frame is well-braced after being installed. The crew want to make sure that their frames are plumb and exactly perpendicular to centerline.
Claes has been working on the keelson. The keelson is a long timber that is fastened over the tops of the frames where they attach to the keel. Here you can see the original keelson as the boat was being cut away.
The new keelson is made of yellow pine, a dense, rot-resistant wood.
These big timbers are cut and shaped with power tools, but the final flattening and squaring up is all done with hand tools.
Eric has been busy forging the hundreds of special bolts that will be needed to hold everything together. One particular type of bolt that will be used extensively in the boat is similar to a carriage bolt, but it has a flat head and tapers on the underside.
A carriage bolt is round on the top, and flat on the underside with a variety of small protrusion to help lock it in place.
Another type of fastener used on the boat is a fillister head bolt.
This type of bolt has a large head that’s slotted so it can be held with a screwdriver. These bolts all start out as lengths of silicon bronze rod.
The rod is inserted into a metal die that has a cutout for the head shape.
The bolt being worked on is on the left. The empty cutout on the right is for another type of bolt called a fin neck. We may see these later on. Anyway, the bolt stock is placed in the die, and the die is set on top of a rather massive anvil.
The top of the rod is then heated carefully with a torch
You can see the bottom of the rod protruding from beneath the anvil. It rests on a metal cylinder that keeps the rod from being driven through the die as Eric works on it.
Once the metal is well-heated, Eric begins to flatten the top of the rod into the die.
This mushrooms out the top of the rod and forces it into cavity of the die.
Here’s a bit of the process in action:
The finished head.
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