Saturday, August 30, 2008

Pegging Gunwales

With the inwale asssembly all set up, the time had come for carving out the outwales - a much easier job than shaping the inwales from before. I had saved some appropriately split Red Cedar stock and quickly worked them with the block plane to form the 3/8" x 1" outwales. After soaking in the lake overnight, they were wetted some more with boiling water and clamped into position following the mild sheer of the inwales.

Soaked outwales; Clamped up

With a 1/4" drill bit, holes were bored every 2nd lashing spot. Left-over square dowels from the miniature canoe build were sharped to a point and pounded into the holes with my birch mallet. Square dowels pinch tightly in a round hole and held the gunwales

Drilling the peg hole; Square dowel peg

Pounding home with the mallet; Pegs all in

Soon it'll be time for the dreaded lashing phase where the gunwales will need to be stitched with spruce root at 2 inch intervals.

Wednesday, August 27, 2008

Stitching Side Panels & Setting Inwales

My pieces of bark were of insufficient quality and width to form a complete one piece hull, so additional pieces of secondary bark needed to be stitched into place forming long side panels. After examining the bark pieces, I used a block of wood (left-over laminate piece from paddlemaking) to draw a horizontal line between intermediate thwarts. The damaged bark above this line was cut with a razor knife and the panel bark properly placed into position to match the intended depth of the boat. These pieces were a bit lighter than darkened winter bark of the main hull which I'm hoping will give the canoe a nice aesthetic look when completed.

Marking out the panel cut

To form the stitch, a old Phillips head screwdriver was filed down to form a sharpened triangular point to serve as an awl. The wetted bark was carefully pierced in 3/4" intervals and the hole temporarily pegged with cedar bits until lashing with root. After about 5-7 pegs, I'd take them out and begin the saddle stitch with pieces of soaked root, tying off the shorted ends before continuing on with a new piece. This gives the exterior the appearance that the stitch is made with a single piece; in reality the inner side of the panel (eventually hidden under sheathing) shows the various lengths.

Pegging & stitching; View of inside panel

I severely underestimated the time it would take to do the running saddle stitch. I assumed maybe an hour a side, but it took me nearly 5 hours with much needed breaks to do both sides of the canoe.

With this part done, I could move on to setting the inwales. This involved cutting up some "height sticks" that would serve to support the inwales at the appropriate measurements. I made some from extra pine staves and marked the height (in inches) appropriately on the back to ensure I didn't mix them up. After loosening the support stakes and stretching out the bark, the inwales were softened with boiling water, placed into position and weighted down with rocks.

Putting the the inwale assembly

Setting on height sticks; weighted down with rock

Up next, I have to carve some outwales so that the even more time consuming process of pegging and lashing the gunwales together can begin.

Sunday, August 24, 2008

Inwale Assembly...Near Disaster!

Once the carved inwales had thoroughly soaked in the lake a few days, it was time to lash them with temporary thwarts to form the inwale assembly. This involved first lashing the ends with soaked spruce roots. I read somewhere that notching the tips would allow the first coil of root to stay in position, so two grooves were cut lightly into the cedar. The ends were temporarily held together with a trigger clamp while being tightly lashing with root. When both ends had been lashed, the inwales began to take their shape.

Cut notches; Binding with wet root; Ends lashed

To put in the centre thwart, the inwales were soaked with boiling water and very carefully stretched apart so that the temporary thwart could be inserted. I needed to push down with my foot and lift with both arms to get the inwale to tightly stretch in this manner. Here's the shot right when the thwart slipped into position and I stepped off with relief.

Stretching apart the inwales for the centre thwart

Feeling confident that the temporary centre thwart was in and there was no signs of cracking, I lashed it into position with some nylon cord and moved onto the intermediate thwart and end thwarts. I had successfully tied in the other thwarts and was working on one final end-thwart when disaster struck! The tips at this end cracked (right where I had notched the cedar)...DOH! With the other end already lashed up, I didn't want to lose the work so far, so I temporarily clamped the broken end and pondered a solution.

Broken Gunwale tip....CRAP!

I figured it could be salvaged by binding right below the crack point while losing only about 2 inches from the original tips. Trouble was the inwales were already under tension from the other lashed end and the clamp would only grip right at the ends where the "repair surgery" needed to take place. I ended up working with one hand on the clamp precariously gripping the inwales in place while frantically shaping the broken inwale with my recently made mini crooked knife. Then with a 1/16th drill bit, I bore 3 parallel holes through both inwales. These were then stitched with strong, waxed linen thread used for leathercraft in a sort of figure 8 pattern. Over this secured end, I further lashed it with spruce root. It turned out amateurish but is holding nice and strong. At anyrate, the inwale tips will be covered by a bark deck piece in the end so no one will know this fudge repair job is there but me and all of you reading this.

Repair with waxed cord; Spruce root lashing on top

Of course, the side with the broken tip is now 2 inches shorter and this affected the width of the inwales at the intermediate thwart (it is now slightly wider than before). This means that the inwales are not perfectly symmetrical, but have a slightly narrower, sharper profile on one end (bow) and slightly wider curve on the other (stern). I don't think this will mess things up because this is the same shape in most asymmetrical hulls today. And since my canoe will need to be stitched from various panels rather than a one-piece hull, it'll have an obvious bow and stern based on which direction the lap joints face. So basically, this boat will feel wrong if it is paddled in the wrong direction, but I can live with that.

Symmetrical Hull; Asymmetrical Hull

Following some practical advice from expert bark canoe builder Ferdy Goode (whom I met at the WCHA assembly a few weeks back), I decided to prebend the inwales since they had been thoroughly soaking in the lake for a while. With some extra boiling water, some rocks, and 4x4 frames from another project, I propped up the ends and weighted down the center of the inwale assembly. My intended design has relatively lower ends with a very modest sheer line difference of about 4 inches from tip to center. So this setup worked out. I was also cautious given the day's earlier breakage so didn't want to push my luck with unnecessary bending

Tips elevated 4 inches; Weighted down for pre-bending

Now they're just waiting to dry out so they can be lashed onto the canoe.

Wednesday, August 20, 2008

Bark Foldup

With the bed all constructed, bark cleaned up, form & stakes all ready it was time for the foldup of the hull. An exciting time for because the inital inklings of a hull shape appear. First, the plywood form was placed back on the cleaned bark and centred with a guideline string. Then it was weighed with down with concrete patio slabs and as as many large stones as I could find in the immediate area. At this stage, there was no way the plywood form would shift out of position.

Form centred with guideline; Weighed down with stone

Next, some gore guts needed to be made. Some of the bark panels already had some minor splits along the edges so rather than cut perfectly symmetrical gores every foot or so, I followed these natural splits and ended up with sufficient gores to foldup the bark. With plenty of boiling water from some electric kettles on hand, I proceeded to soften the bark and begin the foldup process (from stern to bow). Along the way, the overlaps were carefully arranged to ensure the seams pointed in the same direction (towards the stern) while the stakes were driven into their holes to hold the bark loosely into place

Cutting a gore; Beginning foldup; Completed foldup of main panels

Despite the wide tree (40" circumference) I had harvested from, this was still insufficient to form a hull of sufficient depth, so some side panels needed to be cut into place. Using some bark harvested from Canoe buddy Paul's property, I cut rectangular panels to fit along the side. These will need to be stitched into place before any other major work can be done with the canoe.

Cutting side panel bark; panel view inside; panel view outside

After playing around with the positioning of the bark, the inner staves and outer stakes were tied to each other and then these were tied off to their parallel versions to bring the hull side to nearly vertical. Traditionally, tying was done with basswood bark, but I didn't want to harvest from a living tree so I ended up using some non-traditional nylon cord. Before the tie-up, long battens of thin cedar scrap (from the initial splitting to form the gunwales were slide between the bark and the stakes to even out the pressure on the bark. Here's the final result...

The folded up hull

Next up, working on the inwale assembly and beginning the tedious process of stitched the panels together before lashing in of the inwales can proceed.

Monday, August 18, 2008

Constructing Cedar Gunwales

The gunwales are the most intimidating thing for me. Back when making the model canoe, I ended up butchering the carving of the cedar stock with a crooked knife and ended up with horrible inwales. It was the spare set of shearing sticks that I used as a substitute that saved the model project. With this build however, I couldn't afford any mistakes.

Eastern White Cedar (Thuja occidentalis) is the wood of choice for making gunwales, but I have been completely out of luck finding an appropriate length & width tree that is also branch-free and straight grained for at least 13 feet. All my resources spent searching and contacting local forestry folks have turned up a dead end. In fact, a conservation officer at my local Minstry of Natural Resources mentioned that in Muskoka, straight knotfree cedar is next to impossible to find. Apparently, most trees around here grow near the shore of the many lakes & rivers here and have a decided lean and spiraling grain.

The gunwale plans; Typical Muskoka cedar

So for this part, I was forced to go non-traditional route and use store-bought Western Red Cedar (Thuja plicata). This species is available in sufficient lengths but like most construction quality cedar, it is quite notty. After spending hours sifting through a pile of 2x6x12s at various home building places, I found 2 pieces that had a completely straight & knotfree grain on their one side. My intention was to split the boards and use the knotfree section for the gunwales. The other notty pieces will be re-used as temporary ribs, battens, etc.

Most commercial canoe builders simply saw out appropriate gunwale stock (usually out of ash or cherry), but because cedar is so soft, I read that sawing makes it weaker by ignoring the strength of the grain. As such, the gunwales are much stronger if they are split and carved out rather than sawn. So the process began by starting the split with my axe and a carved maul from a piece of green hardwood (never took pics of the process). The split was then continued by hand using a forked birch tree for leverage.

Western Red Cedar board; Beginning the split

Leveraging the split with a forked tree

After splitting the other board and the resulting pieces a few more times, I was left with 3 appropriate stock for the inwales (one backup), two outwale pieces, and two pieces for gunwale caps. Given that the inwales are a very important structural component for the integrity of the canoe, the two best pieces were reserved for these parts. After sorting out, the pieces were shaped down with the axe to within 1/4" of the actual measurement. I did this at the communal firepit to add some kindling for the evening campfire.

Shaping the inwales with the axe

After this it was back to the garage for shaving the inwales down to size. Luckily, since the perfect grain was on the outer edge of both cedar pieces, I ended up with inwales that were square on 2 sides permitting clamping onto the building bed and proper marking out with a combination square. With a block plane, these were shaved down to the dimensions from the building plan (5/8" x 1"). Traditionally this step would be done with a crooked knife, but my skill in carving with this tool is limited, so I stuck with what I knew.

Clamped inwale stock; 5/8" width line marked out

An extremely important step is the beveling of the outside edge of the inwale to make room for the rib ends when they are put into place. To make the bevel evenly, I borrowed a trick from paddle making - mark out two lines on adjacent faces, shade in the space with a pencil and plane down on an even angle until the lines disappear.

Marked out bevel outline; Completed bevel

At the tips, the inwales need to be shaped into an arrow head so they can be lashed with roots. I roughly marked out the wood to be shaved so they would fit. This would be smoothed out later.

Marked out tip outline; Rough shaped tips

At this point, the inwales needed to be soaked overnight in the lake for the actual stretching and assembly part. So they were tied in nylon cord and anchored in the same spot as the bark was previously. After I was done, I went back to garage to sweep up the shavings and dumped the load back at the communal fire pit. The day's mountain of shavings turned into a glorious aromatic fire that night.

Soaking in the lake; End of days shavings and scrap

Saturday, August 16, 2008

Drilling Stake Holes

Back to the bark canoe building. Next up a necessary job with power tools. Since I'm constructing the canoe on an elevated wood building bed, 1¼" holes needed to be drilled for the placement of the stakes used in the bark foldup process. If this were built on the ground, the stakes could simply be driven into the soil, but a building platform allows me to build at a more comfortable height and in the relative climate-controlled setting of the garage.

First, the plywood form was assembled and placed on the bed lined up with the all the guidelines. Some heavy broken patio stones (free discarded stuff from a neighbour) were placed on top to weight down the form.

Frame on bed; Weighted down with stone

Following the pattern on the building bed used for the model canoe, a total of 13 holes were drilled on each side of the boat, for a total of 26. Given that bed is made with nominal 2x10 board, the thickness drilled was about 1½". This took a lot of work with my low-budget drill, but the job eventually got done (noisy!). Once the holes were completed, I did a dry run by placing the stakes in the holes to check for "snugness". All is well and I can now proceed.

Drilling a hole; Completed building bed

Testing the stakes

The pot and grill under the bed were picked up at a roadside flea-market that I always pass by when heading up here. This time around, I stopped to checked it out and ended up with an appropriate pot and grill (plus some other stuff) for $2. I'm intending to use this pot to boil roots and make the pine pitch (which ruins cookware) over an open campfire when the time comes.

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