Rails

I got off the starting line for rail installation today.  Some approach-avoidance going on here.  I glued the first of two laminations for the outside rails.  I didn't feel I could bend the size stock specified in the plans around the forward quarters of this bluff-bowed boat.  Laminations will improve strength as well.

Having the first layer of rails will really increase the structural integrity of the hull.  I've been very nervous having the boat off the jig without them.  Scary with chisels, too.  I'll do both laminations and pop the boat back on its jig and finish the bottom.

The rub rails have me thinking about the inwhales, and that requires decisions about the breasthook, the quarter knees, the style of the gunnels (I'm going to do open gunnels, for sure... wouldn't want to actually finish this boat too soon!)

There are also decisions about the oarlocks that have to be thought through.  I bought bronze oarlocks and gudgeons (two sets of the latter).  My plan is for the gudgeons to be bedded in the space between the planks and the continuous inwhales, serving as integral spacing pads.  That will mean that the spacing plan for the open gunnel blocks will be complicated, and perhaps not as regular as one might like.

The inwhale is 85 or 90 inches and will have to accomodate a succession of pieces as follows:
  • quarter knee spacer block
  • n1standard spacer blocks
  • gudgeon pad 1
  • n2 standard spacer blocks 
  • gudgeon pad 2
  • n3 standard spacer blocks 
  • breasthook spacer block
The thickness of all the spacer blocks will be the same, of course.  The minimum is 11/16 ths, as that is the outside diameter of the bronze gudgeons that will receive the oarlocks.  I don't want to compromise the strength either of planks or inwhales by drilling through them.

The length of the quarter knee spacer blocks and the breasthook spacer blocks is undetermined, but will be a matter of proportioning relative to the piece they augment.

The range of the size of the standard spacer blocks is probably specified, or at least hinted at, in the books.

The gudgeon pads should be, no doubt, some optimal size and shape to transfer power efficiently to the hull from the oars.   I'll guess.

I will carry these blocks below the inwhales and size their length in some relation to the other spacer blocks.  Perhaps the length of two standard spacer blocks and the distance between them? 

The gudgeons will be let into faceted sapele caps that will bridge the rails, planks, spacer interval, and inwhales, about 2 inches of width and about 1/2 or 5/8's elevation (2+ times the depth of the gudgeon top flange).

It seems a bit odd to have two sets of gudgeons for a boat this small.  They will be useful, perhaps, in solo versus rower-passenger configurations.  We'll see.

 

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