America's Most Historic Yacht

A closer look at the floors

Posted By on April 11, 2011

As you can see, the number of frames installed has been slowly growing.

Riley has been supervising frame construction as usual.

“Good job guys, and HEY IS THAT A MOUSE DOWN THERE??!!”

You can see that the forwardmost frames tie directly into the keelson and forefoot.  Here’s how the boat originally looked up forward.


The frames were originally fastened to the forefoot with locust trunnels.  We’re using silicon bronze bolts as you’ve seen before.



In this section of the boat, the frames can have a very solid connection to the backbone, and floors are unnecessary.  However, as the shape of the boat sweeps out from the narrow entry at her bow, the need for floors becomes more apparent.


If the frames were simply bolted to the keel in this section of the boat, the fasteners would only be able to go through the very tips of the frames. This would be a weak connection, and the keel would detach from the frames in short order. Instead, the frames are side-fastened to the floors using multiple through-bolts (You may notice that these bolts have not yet been installed in these floors).   The floor itself is fastened down to the keel, also using through-bolts. This makes for a very solid connection between the backbone and frames.

The keelson rests on top of the floors, and adds another source of stiffness to the backbone.  Here’s how it looked originally,


and how it is now.



The keelson is made up of multiple parts. It is unlikely that even in the best of times, 100+’ lengths of straight, thick stock were available. Instead, each section of keelson is joined to the next using a scarf (sometimes spelled scarph) joint.  This joint is bedded (i.e., the mating surfaces are coated with tar or some other flexible, waterproof material) and the two parts are then bolted together. The resulting joint is exceptionally strong.  In case you thought that this keelson looks shorter than the original, the frames are hiding one of the steps in this joint.  In fact, the keelson is three timbers tall.  You can see this a little better here.




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