Post-apocalyptic Boat Building

Why build skin boats?  I've been asking myself that ever since I started building skin boats.  I've come up with a bunch of practical reasons such as low price but that's not really why I built them. First and foremost I liked the looks of skin boats.  But right up there with good looks was also a yearning for self-reliance.  I wanted to be able to build a boat that at least in principle I could build entirely from scavenged materials with simple tools that if need be I could make myself.
For the sake of convenience, I use electrical tools to cut the wood and synthetic fiber cloth as a skin and petroleum based paint to seal the skin so I don't really build an entirely off the grid boat.  But I like to imagine that I could build a boat strictly from found materials in the manner that people of the Arctic once did.  In a way, the Arctic before the arrival of the Europeans was very much like what a post-apocalyptic (PA) world would be like.  No stores, no factories, no electricity.  Everything you wanted you had to scrounge or barter for.
But a PA world would not look exactly like the pre-industrial Arctic.  A PA world would have a lot of stuff from the industrial world still laying around like scrap metal, wire, plywood, tar and even ready to use hand-tools.  A PA world would not be a stone age world necessarily.  It would be a world that had very little new stuff in it. If you wanted new stuff, like a new kayak for instance, you or one of your friends would have to make it themselves.
Could I build a boat entirely from scrounged materials in a PA world?  Probably.  More than likely, if I wanted a boat with some cargo capacity, I would probably scavenge plywood, and make it out of that.  I don't know what would be available in the way of sealers to keep the boat from leaking, but I could probably find something.
If I wanted to build a skin on frame kayak, that would be fairly easy.  Plenty of construction lumber installed in buildings. I am assuming that I could get some hand saws.  The hardest thing to find would be a suitable skin.  I imagine myself scrounging tarps or awnings and sewing those together, again, assuming I could get a hold of some needles or maybe even make them from bone.  If the tarps were plastic, they wouldn't need a sealer.  If the tarps were not plastic, I would have to figure out a way to make them waterproof.
Hunting sea mammals for skins would be more or less out of the question.  That would require more skill than I have.  Even if I could manage to kill a sea lion hauled out on a beach by stealth, I would need four skins to cover a kayak.  Getting four skins would be way too ambitious.
But how exactly did people of the Arctic build their kayaks in a pre-industrial world?  We have some ideas but Europeans have been going to the Arctic since the 17th century and most of the kayaks now in museums were built with at least some access to steel tools and also possible to milled lumber.
The pictures below show what kayak building looked like in the transitionary period when people in the Arctic still built kayaks, but had industrially sourced tools and materials available to them. The kayak type being built here is Eastern Arctic, that is Canadian Arctic.  These kayaks were long flat and stable and if you killed a seal, you transported the carcass on the wide back deck of the kayak.

Here's a guy in his open air workshop, no special jigs or benches or other sort of stuff you would expect to find in a boat shop. But he does seem to have a handsaw that he is using to trim something in the cockpit area of his kayak.

This guy is sitting in his workshop.  He's using some rocks to level out the deck of his kayak.  He's got the rib blanks stuck into their mortises, all ready for bending and trimming. Or maybe he is going to do three-part ribs with hard corners.  Also not the canvas tent in the background. 

Here two people are working at putting  a skin on the finished kayak frame.  The skin is canvas, not seal hide so one or two people can do the job.  Putting on seal hide usually was a task for many women since the hides had to be kept wet and pieced together which required way more sewing than was practical for one woman to do by herself although it was probably done solo sometimes by necessity. Also not the wood plank in the foreground, evidence of milled lumber brought into this location, probably by ship. Also note the long wide and flat back deck suitable for transporting  the spoils of the hunt.

So what can we say about boat building in an imaginary PA world? Probably possible as long as nobody has any set ideas about what is allowed in the ways of tools and materials.

Eastern Arctic-like Kayak - closing comments

Time to bring the EA kayak building project back to life, on this blog anyway.  Time to make some comments on the building experience, a time when the building is done but the boat hasn't been in the water yet and provided feedback on its suitability as a water craft.  I could have waited another few days to comment on the completion, but I'm thinking that once I try the boat out, I will become preoccupied with how the boat handles and forget all about what I learned from building it.
Part of what building an actual boat is all about is internalizing its structure in three dimensions.  Plans are flat representations of a boat and typically don't show any more than a top and a side view and some cross sections.  But the flow of the form of a boat in three dimensions is a lot more complex than the plans show and to get a feel for the form, you actually have to build the boat.  Once you have the feel, you gain the understanding of how that form interacts with the water and determines performance.
In any case, if you did some careful reading of the title of this posting, you may have noticed that called it Eastern Arctic-like Kayak.  What I mean by that is that when I laid out the shape of the kayak in the horizontal and vertical planes I improvised, that is, I didn't follow a particular plan but rather adapted length and beam to fit the wood that I had available.  I came close to building something that could be called Eastern Arctic, but not quite dead on.  Let's look at some photos.

Here's a picture of the frame just before the skin went on.  If you let your eye follow the right gunwale line you will notice that it has some bumps in it.  I think in general EA kayaks had a smoother sheer line.

Here's a shot of the boat frame. Bow down.  As you can see, the plan view is more like a Greenland hull than an Eastern Arctic.  Part of the problem with working by eye in a tight space.  Should have dragged the frame outside at deck setup time for a better view and probably would have noticed that the back end should have been wider.  I suspect the boat will behave ok, just with a narrower stern won't have as much carrying capacity.  And anybody who knows anything will feel compelled to tell me that I didn't make the back wide enough.  Yeah, I know.

View from the side with the skin on.  The nose is unorthodox, a little taller than traditional.  Looks more like a northwest pacific canoe bow.  Also the sheer line is a tad extreme.  We'll see how that works out.

Meanwhile, the cockpit turned out more or less standard, maybe a few inches longer than traditional.  Soon this boat will have some paint and then hit the water.  Till then I'm holding off on any predictions re performance.  I am most curious to see how the flat bottom will feel and how much stability vs. speed tradeoff there is in such a flat bottom.  Stay tuned.

Eastern Arctic Kayak Construction - Ribs

Back to working on the EA kayak after more than a month's hiatus.
Today I tried notching and bending a stick for ribs, but there was so little wood connecting the segments that I gave up and decided to just do the ribs in three parts.  At the same time, I started refinishing an old wood and canvas canoe so I didn't finish the ribs but got far enough to work out how it will be.
Pictures follow.

View from the bow.  Set sides of the ribs are sitting in their mortises, ready to be trimmed to proper length.  On the ground, just to the left of the EA is a stitch and glue surf ski that somebody dropped there.  Don't know who.  I will have to call some of my friends to find out who it was.  Soon as I get caught up on building, I will go and try out that surf ski.

The first completed rib.  I just nailed the center section to the sides with bronze ring nails.  Seems to work.  The joint will be backed up with some stringers. Note the battens clamped to the sides of the rib sides to mark them for where they will be trimmed.

Side view of the stringer the top of which marks the elevation at which the rib sides will be trimmed.  Ribs are roughly 5/8 by 1/2 inches.

The view from inside in the direction of the stern.  Those ropes look so nautical.

Another shot down the center of the kayak. The first completed rib is visible.  Tomorrow, I trim the rest and cut and nail the remaining center sections in place.

And the ribs near the bow.  With any luck, this frame will be completed soon.

Eastern Arctic Kayak Construction - more frame photos

Yesterday I set up the frame of the EA kayak and gave it a second coat of linseed oil.  With the keelson blocked in and the deck upright, it is easier to see what the boat will look like when finished.  Supposedly, the finished boat will not trim with the waterline parallel to the keelson.  The keelson will in fact sit lower in the front than in back. But we will see. 

Nose forward view accentuates the upsweep of the deck forward of the cockpit.

View from the back shows the downward slope of the deck at the steern.

And one more view from a slightly lower angle.

At this point, I find myself wondering what this boat will turn into and how it will behave.  This is of course one of the compelling things about building a boat of a kind one has never built before.  Invariably, there will be some disappointments and in time, pleasant surprises as well.  Still, if nothing else, the curved lines of a boat are delightful to look at.

Eastern Arctic Kayak Construction - Blocking in the keelson

My last post on the EA kayak, probably should be called EC kayak for Eastern Canadian kayak, mentioned that I blocked in the keelson.  But I didn't have any photos yet.  Now I do. 

This view shows the pieces of two by four that hold the keelson at the desired distance from the deck. Pieces of rope hold the chunks of wood in place.

Here's an overview of the entire assembly.  I installed a block of wood at each deck beam.  I usually do this since when I install steam bent ribs; they push up on the keelson and distort its shape unless I lash the keelson down very securely. But in this case, the ribs will be flat and exert no pressure on the keelson and so would not need all this blocking. I kept the keelson pretty straight.  Regular EA kayaks have some upsweep near the stern to let the kayak turn into the wind when the hunter is approaching game.  But for recreational kayak, turning into the wind is an annoyance and not an asset and so I have chosen to keep the keelson straight.

Here's a view of the setup for an EA kayak. The rib blanks have been inserted into their mortises and await bending.  The height of the ribs will be judged by eye and the keelson won't be added until all the ribs are in place.  This is probably more efficient than what I am doing if you know what the bottom profile of the boat should look like.  I imagine they bent a few key ribs and filled in the rest for a smooth transition between them.

Eastern Arctic Kayak Construction - Interlude

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.

Eastern Arctic Kayak Construction - Doweling and lashing the deck beams

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 don't have steel tools, it is an easier way to do the joinery since it doesn't 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.

Eastern Arctic Kayak Construction - adding the deck beams

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 don't 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 wasn't far back enough.  But then I checked back with the drawing in Arima's 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.

Eastern Arctic Kayak Construction - Shaping the Deck

I've 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 weren't 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. There's 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.

Here's 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 shouldn't 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 isn't 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 don't 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.

Eastern Arctic Kayak - Reconstruction, sort of

I have started the construction of an Eastern Arctic Kayak based more or less on the information provided by Dr. David Zimmerly in various articles.  Zimmerly's own reconstruction is, as he states in his article in Sea Kayaker Magazine, a composite of various designs.
My own construction is in turn a variation on Zimmerly's interpretation. 
Major deviation for me is that I did not want a 22 foot kayak and so shot for something more like 17 feet long and lighter in weight,  hoping to keep is under 50 pounds rather than ending up with a 65 pounder.
Step one is the fabrication of the gunwales which for the Eastern Arctic Kayak are a good deal more complex than two straight boards I normally use for building Unangan style kayaks.

Whereas Zimmerly built his gunwales from two lengths of 3/4 by 5-1/2 boards scarfed together, I started with a 16 foot two by four that I ripped down the middle giving me something like two 5/8 x 3-1/2 x 16 boards which I then built up to approximate the Zimmerly design.  Lots of clamps and Gorilla glue in use. I used Gorilla glue rather than epoxy because Gorilla sets up faster and is easier to clean up than epoxy and less hard on tools.

Here the nose piece goes on.  The design I am copying has the gunwales more or less flat up to the front of the cockpit, then rising from there forward.

After the glue has dried, I faired the lumps out of the top of the gunwales resulting in something like the above.

Here I am using a spline to draw the part of the bottom of the gunwales that I intend to remove.

And here's the whole thing with the top faired and the bottom scooped out.  The gunwales are made to rise amidships because normally, when you bend them, the middle drops down.  The rise counteracts that drop to give you a more or less flat deck.

And some additional rise at the bow to help the bow stay out of the waves.

And that's how it looks faired and trimmed.

And finally, the long view.

I am thinking I probably overdid the midship rise in the gunwales by at least an inch, but I'll stay with it since it doesn't affect the bottom of the hull at all.  Sometimes it is good to go with one's mistakes just to see how much harm they do to the proper functioning of the boat.  After that you can speak with authority on why the way you did it was not a good idea.  Still, you have to admit that what I ended up with looks pretty cool.  And by the way, when you do gunwales that are 3-1/2 inches deep, you don't need fancy lumber since small knots don't affect the structural integrity of the end product by much.