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Re: sea Kayak (re)building
By:Paul G. Jacobson
Date: 7/13/2000, 11:01 pm
In Response To: sea Kayak building (jason Macza)

: I have a Sea Kayak Thats built but it needs to be re build for it to be any
: fun.

: 17 feet, oak , maple, cnavas. cloth

: from a canvas skin to some kind of hard poly or wood exterier.

: it wood be great if someone could join forces with me fixing it and sharing
: in it's use after.

Jason,

If you don't mind, I have a few questions that might help clarify what you are doing.

What part of the world are you located in or near? I assume you are looking for someone who lives reasonably near you.

What part of the kayak needs to be re-built? From the description it sounds like a canvas skin covered kayak. Is the skin missing, torn, rotted, or just old and fragile? Is the frame in good shape or does it need to have parts repaired or replaced?

Sounds like you want to remake a soft sided (canvas covered) kayak as a hard sided one by replacing the canvas with wood. If this is so, you should check the archives of this board for posts by Mike Hanks on the construction of his "plywood walrus" which is a plywood-sided kayak built from the plans for the "Ealrus" as published in George Putz's book.

Mike built a canvas covered version first, and then made a second one with plywood replacing the canvas. As I understand, it was faster and cheaper to build the plywood version.

The basic idea is to take the kayak frame and lay a strip of 1/8th inch or 3 mm plywood on it so that the strip overlaps two of the strips that run from end to end on the boat. These longitudinal parts are sometimes called "chines" or "chine strips". Anyhow, your plywood is a bit wider than the space between two of these, and up to 8 feet long. You use a few small brads to tack the plywood in place, or sue a few clamps, and then trace with a pencil along the chines, leaving a line on the plywood showing the shape the plywood needs to be. Then you use a saber saw or a jig saw or band saw to trim the plywood panel to this shape. The plywood is then held in place with a few tacks (maybe 4 or 5) With a plane, wood rasp, or just coarse sand paper you remove any plywood that hangs over the edge of the chine. Then you layout the next panel in the same fashion. After doing two panels you can either wire them to each other, or use a few more brads to hold them securely to the chines.

There is a lot of freedom in how you attach the plywood panels. You can start at one side and work your way around the boat, or you can do one side first -stoping at the center ( keel line) and then do the other side. Or you can start at the center of the boat, and work to either side. Just don't nail them securely in place until you have several (or all) panels cut. This way you can adjust things a bit if needed. You can also attach the panels with screws or with epoxy resin.

Working with 8 foot long sheets of plywood means that you won't be able to cover the entire length of your kayak with a single piece of wood. adter your first strip is tacked in place, you can easily butt another sheet squarely against the end of the first to get the length you need. Try to arrange the plywood so that these seams don't all fall in a line. Stagger them, like the joints in a brick wall, for greater strength.

When the frame is covered with plywood you will need to paint it with a coat of epoxy resin to keep the wood from absorbing water, and you will need to make all the seams watertight so they don't leak. The easiest way to cover the seams is with a "tape" of fiberglass. This is fiberglass fabric which is woven to be an inch wide, or wider. You'll probably want materials that are 2 or 3 inches wide. If you want, you can cut strips from wider fiberglass fabric, and use them.

You really only need to put fiberglass tape on the seams, but you might want to wrap the entire boat in glass cloth instead. If so, then do that instead of using the glass tape on the seams.

As for budgeting: You'll spend about $50 on epoxy resin if you cover the entire boat with fabric, or $25 if you just tape the seams; $15 to $20 on disposable tools for working with it; $30-$40 for plywood; $50 for glassfabric if you cover the entire boat, or $30 for glass tape, or $15 for glass fabric you cut into strips (pick any one of those last three options)

You MUST then paint or varnish the boat within a few months -- or at least before winter. Figure $20 for a quart of marine enamel, or marine varnish. this protects the epoxy from the Sun's damaging Ultraviolet (UV) light which would slowly damage it.

So, the range is about $105 to $180 for this project. If you have some of the tools already, or do some industrious shopping you could probably cut these estimates down considerably.

Hope this helps.

Paul G. Jacobson

Messages In This Thread

sea Kayak building
jason Macza -- 7/13/2000, 3:16 pm
Re: sea Kayak (re)building
Paul G. Jacobson -- 7/13/2000, 11:01 pm
Re: sea Kayak (re)building
keith hatcher -- 7/17/2000, 7:11 pm