Core Sound Start 6 9 13

 9 Sheets of 6mm Okoume
3 sheets of 9mm Okoume

by noon, I had all the 9mm ripped and ready for gluing the scarfs.  I use a makita Power plane to rough cut the 3" scarfs, and then a block plane, followed by a belt sander.  This took 30 minutes tops.

Next will be to move the panels to the basement workshop for gluing in the climate controlled environment!  I use WEST with one primer coat, followed by a thicken coat with Cabosil or equivalent to make a bonding putty.

I place a wide sawhorse under the joint, then cover with plastic, apply glue, then cover with plastic, and lastly     weight down with a 1X6 with any kind of weight on top.  If it slips too much, I will drive a couple of bronze nails through the set up.  May do this anyways to save time.  the goal is to be able to loft the bottom panels next weekend, and then start on the sides.

Here I am 3 hours later.

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centerboard shaping

The Centerboard has been roughed out to its approximate final shape and I have become a tad obsessive compulsive regarding the final shape.  The photo shows the NACA 0008 shape as it seemed to fit the final shape of the tip of the foil the best.  the NACA 0009 might be better.  My plan is to set a dado router bit to the depth indicated by the template and then  set a guide for the router to follow.  I will set the guides as expanded lines up the foil at several stations as the template can be expanded to fit the width at each point.  I used the plotter at http://airfoiltools.com/plotter/index  be sure to select "no margins" on the printer or things get compressed.  I can generate a NACA foil for several points along the board and then connect the points to expand the lines through the taper.  The router would then follow the lines to cut the lines to be planed to.

 Area that will be inside the trunk is clearly marked.  router will be used to go vertically up and strike marks to plane to.

 I have no idea how I will shape the tip, other than just rounding it off.

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Methane Vents

As  permafrost melts, it releases methane. The methane exits the permafrost via vents which until recently were  small like the one pictured  but in the past year have increased in size to hundreds of feet across.  Careful when you light a cigarette.

Forget the effect of CO2 in the atmosphere on the temperature of the earth.  Methane is the gas du jour because it is 26 times as good an insulator as CO2.  CO2 is merely a gateway gas that sets us up for methane, the really bad stuff.  If you think where you live isnt warm enough, methane is the answer.  A little video here. I am providing a link since the blogger cant be embed flash videos. So flare away.
Actually, we did need to increase the CO2  in the atmosphere to the point where the Arctic was warm enough to release methane on its own accord.  We seem to be there now. Each year promises more melting in the Arctic and further release of methane. So CO2 did its part and can now step into the background.
What does this have to do with skinboats?  Nothing really other than that their use has very little effect on either CO2 or methane concentrations in the atmosphere.  Skinboats, in the current lingo are practically carbon neutral or can be made to be carbon neutral with some effort.  On the other hand, using skinboats does nothing to reduce the release of methane into the atmosphere and though it isnt hurting things, it isnt helping either.

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March 9th update rudder assembly and Centerboard shaping

It has been a very long and cold winter in New England.  Working outdoors to do planing, shaping, and fairing of the blades has been impossible due to the weather and family/work schedule.  I have put in for retirement, so time to work on the boat is not far away.  The weekly 60 hour work week gets in the way of these important things.

today - assembled the rudder head stock, and fitted the shaped blade.  Nothing fancy on the shaping,  I simply planed and sanded a reasonable shape to the flat stock so that the thickest sections were about 1/3 back.  Will coat with epoxy and paint when the days get longer and warmer.

Builders of a CS 17 should note that the leading edge of the rudder protrudes slightly forward of the head stock.  When the pintles are added, it will be in line with the pivot point.  

yup, Its snug, but wont take much to loosen up.  A little sanding and then prime and paint.  

Centerboard shaping - 

From the blank, I attached a NACA 0006 series template to the end of the tip and drew a line around the tip.  Then I set up the router to rout grooves to the depth indicated on the template up and down each side.  

template is sitting on the blade, was attached to the tip.  radial lines kept to the ratio were then scribed on the blade and a guide for the router set up. 

Not bad for a first attempt.  A few low spots and some high spots still, but fixable.  the router and electric plane made short work of this.  Then followed up with the wood eraser (7" disc grinder), and palm sander.  

Leading edge needs some attention, and I still need to shape the tip.  Not quite sure what I am going to do here.  Just a simple rounding over?  When the board is raised partially, this will also be a quasi trailing edge.  

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Eastern Arctic Kayak Construction Shaping the Deck

Ive got the deck of the Eastern Arctic Kayak (EAK) set up.  Beam is something like 29 inches at 90 inches from the stern. I figured that the first three feet of the boat werent in the water so I would put the widest part of the boat more or less in the middle of the part that was in the water which worked out to be at about 90 inches from the back.

View from the bow end. Theres a windlass just back of the bow to pinch in the sides. Aside from the coils of rope that hold the ends together, three spreaders fix the shape of the deck.  The middle of the three spreaders fixes the beam.  The other two spreaders widen the deck by some amount fore and abaft the middle spreader.

Heres an oblique view of the deck, this time from the left rear toward the bow.  The bow rises and the stern drops.  The deck turned out pretty symmetrical, something that sometimes takes some struggle to achieve.  But I cut both gunwales from the same piece of lumber that had been laying outside for about a year, giving it time to stabilize from its green state when I bought it, so perhaps I shouldnt be surprised that it turned out.

And I forgot to mention in the previous post on shaping the gunwales that I backed up the Gorilla glue with some stainless steel screws. My experience with Gorilla glue is that it isnt that strong given the kinds of surfaces that I glue together, that is, unless the two surfaces being glued are both smooth and in good contact, you dont get a very good bond.  Hence the screws.  I could have driven some dowels in there too, but screws seemed just a bit faster and I had a box of them and wanted to try and given that the pieces of the gunwales do not need to move relative to each other, rigid joinery is OK

When it comes to something like the gunwales, what matters is the shape and not the details of how the shape is achieved.  I used to think that these things needed to be done in a traditional manner like with doweled scarfs and no glue or screws, but then doweled scarfs were not particularly traditional anyway.  Much of what we think of traditional kayak building technology evolved in post contact times, that is, post contact with European traffic which introduced both new materials and tools.  The only truly traditional part of kayak building is to do the job the best you can with the tools and materials available to you.

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