четверг, 16 февраля 2017 г.

Building a Skin-on-Frame Kayak – Part 4

Building a Skin-on-Frame Kayak – Part 4
Building a Skin-on-Frame Kayak – Part 4

Planing the hump out of the gunwales near the bow of the kayak

Before proceeding to building the flat deck beams, Russ and I had another look at the sheer of the gunwales and determined that a slight hump was still noticeable near the bow of the kayak. A few quick passes with the plane removed the hump and we were ready to move on.


Although we are following guidelines and standardized instructions for the construction of this kayak, an equally important element is the process of modifying and judging the progress of our work by “eye.” The organic process of building this kayak is best reflected in moments where Russ and I take a step back and assess our progress with a little common sense. This is what enabled us to notice the “hump” near the bow and correct it. Because the boat’s size is established by anthropomorphic measurements no two kayaks are the same therefore standardized instructions can only be used up to a certain point.


Determining where to cut the deck beam so it fits with the gunwale

Our next step was to install the flat deck beams, which supply strength across the width of the kayak. In total we had 8 deck beams to shape and secure to the gunwales. Shaping the deck beams was a tedious task as it required us to continually verify that the angle joining the gunwales to the deck beams were consistent and accurate.


Cutting a deck beam to fit

Once we had established a desired fit between the deck beams and the gunwales we proceeded to drill and peg them together with dowels (the same way we had fastened the tips of the gunwales together last week).


Pegging the deck beam in place with wooden dowel

Now that the desired shape of the gunwales were locked into place with permanent deck beams, some of our temporary braces were no longer needed and could be removed. The two end braces at the bow and stern will remain until next week when we replace the support they provide with lashings.


Check out the next “Building a Skin-on-Frame Kayak” blog to see how we shape the masik.


You can read Part 1 by clicking here.


Andrew and Russ cutting mortises

I arrived at the museum a bit early today. I wanted to look at three specific kayaks on display at the museum. All three are Greenland skin on frame kayaks just like the one Russ and I are attempting to build. Clearly Russ and I benefit greatly from having so many valuable resources available to us.

MyBoatPlans
Not only can we find actual Greenland kayak artefacts in the museum but the kayak gallery also features a video demonstrating the traditional methods of building skin on frame boats. Conveniently the central figure in the video also happens to be the author of the book Russ and I are consulting during this project. After a half hour admiring the kayak gallery, I joined Russ in the shop and we set to work.


The ribs of a kayak are seated in slots in the underside of the gunwales. The distance between each slot, known as a mortise is 8”. This was our first task for the day and by using a plunge router we got the job done in no time.


Next came addressing the sheer line of the kayak. The sheer line of a kayak describes the characteristic sweeping curve that extends from the tip of the bow to the end of the stern. The sheer of a kayak is accomplished by tilting the gunwales so that they are wider apart at the top edge than at the bottom. To achieve this we needed to plane the outside of the gunwales down to 17º starting a ¼” from the inside edge. For this step, we could have certainly used various power tools but there is something rather pleasing and even cathartic about using hand tools. After shaping the gunwales to get the desired effect we preceded to shape the tips of the gunwales to accommodate the bow stem piece which will be added at a later time.


Cutting the notch out of the gunwale to accomodate the stem piece later

Our next task was to build five temporary braces that will hold the gunwales in place. Following the advice of our guide book we used a piece of ¾” scrap plywood to build the braces. With our braces built and the gunwales properly set in place, Russ and I packed up and called it a day.


Temporary braces holding the gunwales in shape

You can read Part 3 by clicking here.


Original article and pictures take https://canoemuseum.wordpress.com/2012/04/05/building-a-skin-on-frame-kayak-part-4/ site


Комментариев нет:

Отправить комментарий