America's Most Historic Yacht

Carlins and a Keelson

Posted By on August 27, 2013

These days, most of the work is focused on installing carlins in the deck. Carlins help to support the deck, and attach to the deck beams via ramped half-dovetails. The slots cut into the beam look like this:


Or if you prefer a drawing…


The carlin slides down into the joint. The ramp keeps it from sliding right through the deck beam as could happen with a normal through-dovetail, and the dovetail locks the carlin in place and keeps the beams from moving.

There are a lot of carlins in the deck.


Some go fore-and-aft like the large ones in this photo,


and some go side to side. You can see an example of the latter at the bottom of the above photo.

The locations for all of these are drawn out and posted up on deck.

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Sam was an IYRS intern and is now with the crew full time.  Here he’s flattening a deck beam face before laying out the next carlin.

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He’s got everything he needs right at hand.


Leo’s been working on the beam shelf. The beam shelf is a long timber that runs the length of the boat, and fits up against the underside of the deck beams (hence, beam shelf).


If you’re familiar with boat parts, it acts like a bilge stringer in that it helps to support the hull fore-and-aft. These are pretty straightforward along the middle section of the boat, but as he gets to the stern, the sudden curve in the hull makes fitting this part a real challenge.

He’s been using a very long batten to lay this part out.


There’s really no substitute for a good quality batten when it comes to creating fair lines on a boat.

The keelson is now complete. The keelson sits on top of the floors, and is made of laid-up layers of yellow pine.


Much of the material for the keelson came from the old building floor that had been constructed at the beginning of the project. This is the platform that all of the frames had been built on.


Some of the material came from old ceiling planks that were not good enough for re-installation, but could be made to work for the keelson. In case you didn’t know, the ceiling is the planking that goes on the inside of the boat’s frames. Here’s the ceiling back when it was first being removed.


The ceiling and hull planks were fastened to the frames with wooden trunnels. Some of these trunnels remained in place and are still visible where the saw cut through them.


Others came out when these old timbers were cut.


Even if it’s not in the same place, it’s good to see original material staying in the boat.

Andy has been drilling for bolts that connect the keelson to the keel. Before the keelson was installed, Leo drilled down through the bronze floors and the keel. Now that the keelson is in place, Andy is drilling back up through those holes from below to complete the hole through the keelson.

First the drill bit is pushed up through the hole in the keel by hand.


Then the drill is attached to the bit. It’s a very long bit.


The long shaft that’s been welded to the drill bit has a smaller diameter than the drill bit itself. To make sure that the drill runs straight and true through this hole, a bushing has been made that has the same outer diameter as the drill bit and the same inner diameter as the rod. The bushing snugs up into the keel bolt hole and helps to keep the bit running true as it exits the top of the keel and goes up into the keelson.


Here’s the bit just emerging through the lower hole in the bronze floor.


Going up into the upper hole in the floor.


And now it’s a long slog through the layers of yellow pine that make up the keelson.

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Drill’s getting closer to the keel, almost there.


And the tear-out that appears at the top of the clamped block tells us that he’s through.

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The pine block that’s clamped onto the keelson guarantees that the exit hole at the top of the keelson will be clean and neat. The pine block is sacrificial, so the tear out there doesn’t matter.

More next month…


3 Responses to “Carlins and a Keelson”

  1. Tim Murray says:

    Excellent sequence, Tom. Next best thing to being there! Re the beam clamp, how will this be coordinated with knees and lodging knees? I understand many of the originals are going back in.
    Tim Murray

  2. Hi Andrew, your work is awesome.
    i have a question,
    Dovetail only takes glue? or have any other setting.


  3. admin says:

    Hi Hugo,
    The half dovetails where the carlins join the deck beams typically do not get glue. When the decking is fastened to the deck beams, everything locks together then. I think the glue would just make future repair work harder.

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