Tuesday, December 20, 2011

Skin-on-Frame Kayaks

Here is the skin-on-frame kayak I built from scratch.  Once you build one, you will be hooked.  I'm planning on making a few more this spring.
      My friend has recently moved into a warehouse (it's cozier than you would think), so he has plenty of workspace.  Better yet, he wants me to teach him how to build kayaks!  We are thinking of making some traditional skin-on-frame kayak.  In this ancient style of construction, a waterproof skin is stretched across a wooden frame and sewn together to create a kayak (or other type of boat).  Whale or other hides were traditionally used for the skin and, the frame was typically made with bone, or driftwood.  More modern interpretations of skin-on-fame kayaks use a range of materials for the "skin" including latex painted canvas, polyurethane coated nylon, or PVC sheets.  It may not be true to tradition but, today, most people don't have access to narwhal skin.  The frames are still usually made of wood, but there are two common styles of frames.  Traditionally, wooden gunwales (the part of the boat where the hull and deck meet) were carved and spread apart with wooden crosspieces.  Wood strips were then steam bent into curved shapes, called ribs, and inserted into the bottom of the gunwales (via mortise and tenon joints) to create the hull shape.  Longitudinal stringers were then lashed to the ribs to complete the hull.  This picture should make it a little more clear.  A less traditional way of constructing the frame is the fuselage style.  In this style, gunwales and longitudinal stringers are attached to plywood cross sections to provide the shape of the hull.  As its name suggests, it is similar to the fuselage construction of airplanes.

Here is my fuselage style kayak frame.  Note the plywood cross sections as opposed to steam-bent ribs.

      I have built a kayak using the less traditional, fuselage style and, it came out pretty nice.  This time, I want to build a more traditional frame.  The fuselage frame worked, but the cross-sections made it hard to get gear in and out of the boat.  Plus, I really like traditional technology, and lashing a frame together would make me feel like a made a boat in the most traditional sense (aside from using a narwhal hide and gathering all my wood).
      When I paddle my boat, people are always impressed by its beauty but, somebody always asks if it is safe or seaworthy.  A lot of people reading this are probably skeptical too.  Let me just put it this way.  I broke in my kayak by taking it on a 3 day, 30 mile coastal paddle during a continuous small craft advisory.  It did just fine.  In fact, it is still doing just fine over a year and a half later.  Many Native-American cultures used skin-on-frame kayaks to hunt and fish in harsh, arctic conditions.  To put it simply, the skin-on-frame kayak is a result of thousands of years of testing and modification by generations of designers.  The technology "evolved" with the cultures and has proven its worth.  Skin-on-frame boats are tough.  If they weren't, the technology wouldn't have survived into the modern era.

1 comment:

  1. Hi Chris,

    I stumbled across your blog while I was doing some research for SOF kayaks. I want to build my own, but can't decide between the traditional and fuselage methods. Besides getting gear in/out being a problem with the fuselage style, did you notice any other cons to it? Was it weaker than the traditional style or maybe flexed more in rougher weather due to fewer "ribs?"