Lashing the Frame – Skin on Frame Kayak – E5
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Lashing the Frame – Skin on Frame Kayak – E5

October 18, 2019


Hi, I’m Nick Schade at Guillemot Kayaks. In this fifth episode of making the skin on
frame I am lashing the stringers to the frames. A few of the frame pieces need to be assembled. Here the stern stem frame is fitted to the
last sectional frame. I use a waxed nylon floss called artificial
sinew which is an untwisted thread that has a thin cross section and holds a knot well. The sinew is tied to the part and then threaded
at least 3 times through each of the holes and pulled tight after every pass. The wax helps hold it tight after pulling. I tie a couple knots around the bundled sinew
to secure the ends. The assembled frames are clamped back to the
risers to hold them in their approximate location. At this point I don’t sweat the height, it
is enough to just get their lengthwise spacing established. The frames include some longitudinals for
mounting the foot braces. I’m inserting some stainless steel t-knots
so the foot braces can be bolted in place. I whack them in with a hammer to set the spikes. It is easier to mount the braces now while
the bolt holes are easily accessible. These rails are assembled to adjacent frames
in the same way I lashed together the stems. The final assembly are the frames around the
seat which include rails to eventually secure a backrest. The wide main stringers can now be placed. These run perfectly horizontal and serve to
define the height of all the forms. I hold them in place with a few temporary
zip ties. The ends of the main stringers will be lashed
into a hole in the end frame. A figure eight knot in the end of the sinew
serves as a stopper. I thread the sinew through a couple hole and
then tie the knotted end around long end with an over hand knot. When I pull this loop tight, the overhand
knot works its way up the sinew until it snugs up against the stopper knot. The goal is to lace the sinew through the
holes enough times that the parts are securely held together. Just one loop is usually not enough, but as
you pull more loops through the holes, it acts like a block and tackle, providing more
and more mechanical advantage until the parts are tight. I like to get at least three passes between
each hole. This lashing was doing a fine job of pulling
the stringer in from either side, but pulling the sinew tighter had the tendency to push
the end form to the right. I needed some lashing to pull the stem back
in. The addition of a small hole through both
stringers allowed me to get tension to keep the stem snug against the ends of the stringers. After lashing both ends, I brought in the
keel stringer. Using holes through the keel avoids creating
lumps along the bottom which may cause abrasion. I situated these holes so the lashing pulls
the keel tightly into the hook on the stem. After securing the bow, I lashed in a few
of the frames along the length before moving to the stern. Learning from the bow, I started with some
lashings to hold the stringers together, then went directly to a pattern that pulled the
frame tightly against the ends of the stringers. Shooting holes in on either side of each frame
did a good job of pulling the keel tightly into the slot. While the sinew is quite thin it would leave
a bump if it passed over the keel. Because the bottom is the mostly likely point
for the kayak to hit stuff, avoiding the bump should reduce abrasion. Getting all the frames lashed to the main
stringers and the keel starts to lock the shape in place. Later bending in of the additional stringers
will add some force that may try to curve the frame. Hogging, where the ends of a boat droop down
is common with skin on frame kayaks. Lashing these frames now should avoid hogging
later. But once these three stringers are secured,
I could start right in with the rest. I didn’t bother lacing the sinew through holes
in any stringer beyond the keel because I figured any bumps in the finished surface
elsewhere were not a big deal. There are a lot of lashings needed, but once
you get into the flow of it, they don’t take long. With these side stringers, I’m just trying
to get the end tucked in tight to the stem frame. The chine stringer runs from the stern up
to the keel just short of the bow, then a secondary stringer extends from the bow frame
to about half way back where it blends in with the chine. I need to lash the forward end of the chine
stringer into the keel stringer. The gradual taper makes it tricky as the lashing
wants to slip forward. Since the spacing is closer up forward, this
loosens up the lashings. I originally just tried wrapping the sinew
tightly around the stringers from the narrower end back. But the wraps just slid down the taper. I solved this problem by drilling a hole through
all the stringers and starting my wraps there. This prevented slippage and eliminated the
bumps along the keel. With the bottom stringers all installed, I
flipped the frame over, and started with the foredeck stringer. Like the keel, I positioned the holes so the
lashing pulls the stringer in tightly against the stem notch. I then thread some sinew through the hole
and tie a figure eight knot as a stopper. A figure eight has the end wrap over the sinew
then circle around behind then the end goes down through the loop. The overhand knot loops around other leg,
down under the sinew and down through the loop. When you pull it all tight the overhand knot
slides up to the stopper knot and then pulls the loop snug against the stopper. By forming a V shape with the lashing I create
the ability to pull it even tighter when I’m done. The last pass before the knot comes out at
the top of the V. I thread the sinew under the lashing and make a couple wraps around
the needle. When I pull this snug, it closes up the bottom
of the V, cinching all the threads even tighter. Another pass under the lashing and wraps around
the needles lock this knot in place. As added insurance, I add a figure eight stopper
knot on the end. I use the tip of the needle to pull it as
close to the lashing as possible. These lashings are really robust. Since the lightweight frame is bound to flex
a little bit any stiffly glued connection between the stringers and the frame would
likely crack and break. The sinew lashing is flexible and resilient
allowing movement without breaking. Gluing the low surface area joint would be
problematic. Most waterproof adheasives, such as epoxy
are stiff and relatively brittle. The edge grain of the plywood frames forms
weak joints. As a result this lashing will be substantially
more durable than glue. The aft end of the fore deck stringer gets
lashed to the forward cockpit frame and then the coaming ring will be lashed to it. I ended up shooting a few extra holes in the
coaming ring to provide lashing point between the ring and the frames. The ring lies on top of the frames and gets
lashed down directly to the frames. The front of the coaming ring is lashed directly
to the ends of the stringers, tying the whole system together as one unit. This whole process of lashing together the
frame is kind of fun. While there are quite a few lashing point,
it is nothing compared to wiring together a stitch and glue kayak or fitting strips
on a strip built design. It is quiet and relaxing and provides quick,
satisfying results. I really like the look of the completed frame. It is kind of a shame to hide it all under
the skin, but that is what I’ll be showing in the next video. Feel free to post any questions to the comments
area. I’ll get to them as soon as I can. Please support these videos by hitting like,
sharing them with your friends and subscribing. If you would like to participate more closely,
please consider joining the community of patrons on Patreon
Until next time, thanks for watching and happy paddling.

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  1. I would hope you will use the translucent skin on this. That "Chinese lantern" look is so cool. Only way it could be better was if it was clear, unless of course, you're planning on doing nude kayaking.

  2. Cette technique plus proche de la construction traditionnelle est très intéressante. J'ai hâte de voir la suite. Bravo Nick.

  3. Great video. The presentation is very nice. I'll be using some of your construction decisions on my next build. Rich with good thinking.

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