Hi folks,
sorry for the long delays, I have been remiss about getting up to Newport to document this project. Here’s the progress during my visit in December.
The oak lower hull is essentially finished at this point. A few planks still need to be installed, but not many.
The inner planking, known as the ceiling planking is really moving along. The faying surfaces are painted with red lead paint (the brilliant orange color) to preserve them. The space behind the ceiling won’t be accessed for a very long time.
The ceiling is double planked yellow pine. Looking aft,
and looking forward.
You can see that the port side has been finished and the starboard side is still in progress. The finished port side:
The starboard side, showing the underlying layer and the top layer coming down from above.
The semicircles are used to locate the fasteners in the underlying layer. Without these marks, the carpenters wouldn’t know exactly where the screws below were, and could accidentally hit one as they fasten the top layer planking.
The two layers of ceiling planking are glued as well as screwed together. These two layers will help make this a tremendously strong hull.
The topsides planking is now underway. This is the more reddish wood up above the lighter oak.
The topsides planks will be double planked, rather than carvel planked like the oak below. Double planking, like the name implies, is made up of two layers of planking, laid so that the seams are staggered. Here’s an illustration of a typical installation (thanks to RotDoctor.com for the drawing)
Double planking is not caulked like carvel planking. The seams are made tight, and the result is often a very smooth hull surface, uninterrupted by plank lines. Coronet will probably not use an impregnated fabric between the layers. Instead they will use glue (not sure right now if it will be epoxy or 3M’s 5200 adhesive).
The lower planking is moving along well.
Staging has been set up high on the hull in preparation for the topsides planking.
Coronet is being planked from the bottom upwards. We are using white oak both for its strength and it’s ability to bend when steamed. There isn’t a lot of twist at the bow of the boat,
but the stern is another story entirely.
There is a tremendous amount of twist where the hull transitions from vertical at the keel to nearly horizontal.
One way to cope with this transition is to use thinner (in height) planks, called stealers, in the area of the sharpest curve.
Without the stealers, you need a very thick piece of wood to bridge the same gap that could be bridged by two thinner pieces of wood.
In this illustration the dark lines show the thickness needed to span a curve, with the dotted lines showing the final consistent thickness of the plank.The pink lines show the thickness needed for two stealers to bridge the same distance.You can see that there is much less wasted wood with the two plank solution.
Each plank is cut so that there is a solid wood-to-wood connection between them along the mating inner faces.
The angle of the mating faces changes along the length of the plank as the shape of the hull changes.If the boat were shaped like a square box, you could make the edges of all of the planks square (i.e., 90 degrees) and they would fit together perfectly.Since the planks are going onto a curved surface, you have to bevel the edges so that they mate properly.Here’s an illustration.
On the left side you see planks that are fitting up against a curved frame where the mating edges are left square.You can see that only the outer edges touch, leaving a gap on the inside.On the right is an illustration of the same planks, with the top plank’s bottom edge beveled to properly mate with the lower plank.Only the innermost one third of the mating surfaces needs to actually touch. The outer two thirds are opened up to form a caulking bevel.
You can find a nice video of the plank cutting process here.
Here’s a close-up of the caulking bevel.
It’s good practice to set up your work area with all of the tools that you’ll need close at hand and well-organized.
While trunnells are the primary fasteners for the planks, the ends are first locked into place using a pair of bronze hanging spikes.Once the plank is clamped into position, the shipwrights drill two holes into the ends of the plank.
The drill creates a round hole, but the hanging spike is square in cross-section.To avoid splitting the end of the plank, the team first drives a specially formed spike into the hole to square up its sides.
This is driven in just far enough to change the round hole in the plank to a square hole, and then removed.
After this, the bronze hanging spike can be driven in fully.
The hanging spike is driven in below the surface of the plank, and will be bunged over later.A backing out punch is used like a large nail set to help drive the spike in completely.
The ends of each of the lower planks butt up against one another.This vertical seam is called, unsurprisingly, a butt joint.
In order to avoid butt joints in the topside planking, these planks will be scarfed together to form one long, continuous plank.Here Eric is working on the jig that will be used to make those tapered scarf joints.
The crew has been making steady progress on the hull planking.
Here’s how things looked in mid June.
Port side
Starboard
The planks are trunnel fastened, with a few bronze hanging spikes to hold everything in place while the trunnels are set.
The butts are all spiked.
So are the hood ends.
In case you’re not familiar with trunnel fastening, it’s a great way to hold planks. The trunnels (aka “tree nails”) are made of locust. They’re often made in a machine that cuts them much like a pencil sharpener cuts a pencil. They’re cut to a set size, and then dried. This shrinks them a tiny bit. When the plank is installed, the carpenters drill holes through the plank and into the frame just a shade smaller (as in a few thousandths) than the trunnel diameter to insure a tight fit. The trunnel has a slot cut into it to accept a thin wedge.
The trunnel is driven into the plank using a large wooden mallet called a beetle.
Once the trunnel is driven into the hole, a wedge is set into the slot to lock the trunnel in place. The wedge widens the top of the trunnel ever so slightly and makes it act like the head of a nail.
As the trunnel gets wet, it expands and further locks into place. Even though the end grain of the trunnel is exposed to the water, the wood is so rot-resistant and compressed, you rarely see them rotting out.
One advantage of fastening with trunnels is that you don’t have to worry about hitting metal fasteners as you fair the hull. They don’t require bungs either, so they speed up the process of planking.
By mid-June, part of the lead ballast keel had been through bolted onto the keel.
The stairway leading down from the deck into the main salon has been set into place to show its location.
The deck beams are installed, and lodging knees are going in to brace everything.
It’s going to be planking season for quite a while now. Sorry for the long delay between posts, but here we go.
As of November, the garboard (the first and lowest plank on a boat) was being installed. Here’s the starboard forward end.
Louie Sauzedde has joined the crew working on planking.
He has a series of informational videos that you may find interesting under the heading Tips from a Shipwright on YouTube.
Louie was fairing the deadwood by the sternpost when I stopped by the shop last November.
Everyone has their own take on how to spile planks, and Louie is no exception. Spiling is the process of transferring the shape of a plank as it’s laid out on the boat to the raw planking stock. It’s part of a multi step process that goes like this:
Lay out the plank lines on the boat. The plank locations are marked out along the length of the boat using long, fair battens. This allows the builders to step back and see how the planks will eventually look. Any wiggles, flat spots, or unfair lines are addressed here. The edges of the planks are drawn onto the frames.
Spile the planks. This step copies the shape of the drawn planks onto flexible stock (often thin plywood) that can be removed from the boat.
Copy the spiling pattern onto the plank stock. In this step, the spiling pattern is laid down onto rough stock, and the shape is precisely drawn.
Determine the planking bevels and draw them onto the stock as well. Planks rarely have square edges since they attach to surfaces with flare and hollow. In order for two planks to butt together tightly, their edges need to be beveled.
Cut out and bevel the planks. Cut a slight caulking bevel along the edge to allow for later caulking. Shape the inner face of the plank to lie snugly against the frames as need be.
Steam the plank if needed (usually just for areas with twist or curve).
Attach the plank to the frames with just enough hanging spikes to hold it solidly in place.
Drill and trunnel the plank to fasten it to the frames.
Phew. And you thought they just threw those suckers on.
There are 4 spiling methods that I know, and I’ll show you a couple of them. All spiling methods use some kind of flexible wood as a base It’s often plywood, but it can be anything that fits easily against the frames. This is called spiling stock. The spiling stock has to fit within the edges of the plank that it’s copying. The stock is tacked onto the frames, and the locations of the plank lines are copied onto the stock. Some people do this using a compass like this:
The point of the compass sits right on the plank line and a curve is drawn onto the stock. When that spiling stock is placed on the plank wood, the curve can be used to re-create the exact location of the compass point (and thus the location of the plank line) onto the wood.
Some people like hot gluing little wooden fingers onto their planking stock.
The tips of these fingers are placed to just touch the plank line. The nice thing about this method is that it’s easy to copy the pattern onto the plank stock by tacking down a batten that just touches the tips of each of these fingers.
The compass method is a bit slow, and the finger method requires making lots of little fingers and messing around with hot glue. Louie likes a third method. He uses sticky file folder labels as fingers.
This method is quick, inexpensive, and you can easily rip the old fingers off and replace them with new ones to reuse the spiling stock.
By the end of January, the planking was marching right along. Here’s a butt joint with the caulking bevel clearly visible below it. The bevel opens up from the line marked on the plank.
A butt joint is where two planks butt up to one another at their ends. These joints are commonly located on frames so that the end of each plank is solidly fastened into a frame.
Here you can see the hanging spikes (dark) and the trunnels (light) holding the planks to the frames. The hanging spikes are large bronze square nails that hold the plank in place until they are fastened with the trunnels.
Trunnels (short for “tree nails”) are wooden pegs, usually locust for rot resistance that are driven though the planks and into the frames. A small wedge is driven into the end of the trunnel just before it’s pounded home to add extra gripping power.
This plank is from the Charles W. Morgan whaling ship. Coronet’s planks are a little nicer looking…
Often planks are steamed before they’re attached to the boat. Steaming softens the wood a bit and makes it more amenable to twisting and curving. The usual way to do this is to build a steam box, pipe in hot steam, steam the plank (1 hr. / inch plank thickness), carry the hot plank to the boat and clamp it in place. After the plank has cooled for about a day, it’s fastened to the frames.
Louie decided to try steaming the planks in place. He bagged the plank, clamped it to the frames, and piped steam directly into the bag. After cooking for the proper amount of time, the bag can be removed and the plank clamped again to the frames.
Here’s his steamer in action. It’s a section of double walled stove pipe with a coil of copper piping inside and a burner below.
Water feeds through the copper pipe, flash boils, and comes out of a rubber hose as you will see.
In this video, Louie has just gotten the generator going and it’s kicking out steam like there’s no tomorrow. He plugs the hose into a pvc pipe that goes into the bag and spreads the steam out along its length through a series of holes. You can see the white pipe inside the bag here.
Unfortunately, the pvc was softened too much by the steam, so the pipe / hose connection failed. There’s more than one way to do this, however, including just putting the hose directly into the bag. We’ll see how the system has been modified during the next visit.
In the meantime, here’s the planking progress so far. Starboard:
Port:
Leo brings in a plank for spiling.
The overhead crane is priceless.
Up top, the deck furniture is in place and the tops of the frames have all been tied in at bulwark level.
