Yesterday I blocked in the keelson on  the inverted deck of the kayak in preparation for installing the ribs.  I am now at a crossroads where there are a number of ways to construct the ribs.  Not knowing exactly what the shape of the bottom of the kayak should be since I have never built this type of kayak before, I have to come up with a way to do this.  I can think of any number of ways to proceed but would like to go with the aboriginal scheme of shaping the ribs, whatever that is. 
Zimmerly is of no help here. His article in Sea Kayaker gives you the exact dimensions to cut the ribs to.  This only works if you also shaped the deck exactly like he instructed.  Since my deck is not shaped like his, his dimensions will do me no good.
I could do the ribs the way I normally do them, that is, steam bend them which would produce rounded chines and a slightly rounded bottom, but I want to go for the flat bottom and hard bends in the ribs approach that is more common for the EA kayak.  I guess I will just have to experiment and see what happens.

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Construction progresses.  After I set up the deck, I started adding deck beams.  They are temporarily nailed in place 3/4 inches below the top of the gunwales. 

Before starting to add deck beams, it is a good idea to stabilize the deck by lashing the ends together and also doweling the two sides together so they dont shift with respect with each other which would cause asymmetry in the deck.

The deck prior to pegging the ends and dropping in deck beams.

And here, at the end of the day, all the flat deck beams are trial nailed in place.  You could of course dowel all the deck beams in place as you go but trial nailing them lets you do some last minute adjustments in deck shape before committing to more permanent joinery.

The last two deck beams to be added are the two curved ones just fore of the cockpit.  Shaping them is more time consuming than shaping the flat ones.  Unlike the flat deck beams which are mounted 3/4 inches below the top of the gunwales, the curved beams are mounted flush with the tops of the gunwales.  A batten is temporary clamped in place to show the curve that the deck stringer will take.  The beam just in front of the cockpit will elevate the front of the coaming 4 inches above the deck.

And here is a view down the length of the boat with all the deck beams in place.  The number of beams, coincidentally is less than in a traditional boat to keep down the overall weight of the finished boat.

And just before I started adding in the two curved deck beams, I had a crisis of faith about where the widest part of the boat should be.  Seemed like it wasnt far back enough.  But then I checked back with the drawing in Arimas book on EA kayaks and it appears that my placement was OK.  Seems that the original for this adaptation was a demo boat done for a Canadian museum and was shorter than the type usually is because available lumber was only 16 feet long.  So a shorter version with a slightly more forward beam was built.  In any case, the first boat of a type is never just right and gets modified when the second one is built.

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In the previous post we looked at cutting and installing all the deck beams.  I chose to temporarily nail them in place.  While the method I chose is not traditional for this type of boat, it works well enough and is quick.  The Eastern Arctic method is one of digging shallow divots in the sides of the gunwales and pointing the ends of the deck beams to fit into the divots. See the Zimmerly Sea Kayaker Article for details on how this works. The main advantage of this approach is that if you dont have steel tools, it is an easier way to do the joinery since it doesnt require as much precise cutting.  The lashing which comes next holds the ends of the deck beams in their divots.  This method was also apparently used in Greenland until contact with whalers made steel available to them.  East Greenlanders also used the divot method.
The following photos show some details of my hybrid approach of doweled deck beams and traditional running lashing. Doing lashings like everything else in kayak constructions can be done in a number of different ways.  Aside from the lashing patterns themselves there is also the local vs. the running lashing approach.  Running lashings seem to be favored where the lashing material is rawhide.  Where string was available, lashings were more likely to be tied off at each joint.  Another factor in the decision of which way to go was the strength of the lashing material.  Weaker string would take multiple turns at each joint which favors tying off the string.  Running lashings favor a stronger binding medium like rawhide since a break of the lashing anywhere along its length would make the whole run unravel. 

This lashing runs left to right.  The string goes into a hole in the gunwales under the deckbeam to the outside of the gunwale.  Then it goes up in another hole in the gunwale and exits at the top of the gunwale.  Next it goes through the deck beam, loops around the string coming in at the left and heads off on the right.

This shot shows the lashing moving from deck beam to deck beam. The lashing material is tarred seine twine a little under an eighth of an inch in diameter running through 3/16th inch holes.  The tarred seine twine is stiff enough so that it can be pushed through the holes without the need to additional tools.

A view from the outside showing both the dowels and the lashing coming out of the gunwale at the bottom and then heading right in again above.  Note that one of the downsides of dowels and this lashing scheme is that you have to be careful not to drill through the dowels when making the lashing holes.

A view of the lashings from below the deck beam.  The lashing makes its way through the gunwales and comes back again, taking off to the right after looping around its incoming arm from the left.

And finally, a side view of the arrangement.  Note that the deck beams sits about 3/4 of an inch below the top of the gunwale.

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