Boat Building Forum

Find advice on all aspects of building your own kayak, canoe or any lightweight boats

Great idea for a fast sit-on-top kayak
By:Paul G. Jacobson
Date: 9/9/2001, 11:05 pm
In Response To: A new method to build a kayak.......??? (Mark F)

Creating a foam mold for a kayak can be very simple and need not be very expensive. If you use a stack of a dozen (or so) layers of 1 inch thick plastic-foam building insulation, you can determine the hull otline by marking widths taken from a table of offsets directly on the panels, and then trim them with an inexpensive heated wire tool. While you are working on a panel, cut out the shape of your cockpit, or paddling seat, at the same time. You can start a cut in the center of a panel with a knife and then enlarge it with the hot wire cutter.

If you want a small paddling seat molded on top of your boat you just have to carve the top 4 to 6 layers of foam. If you want a large, deep cockpit which you can crawl into, you'll just be cutting out more material from the centers of a few more panels.

Stack these up, and hold them together with a light application of building adhesive. You just have to round down the soft edges to get your symmetrical shape. A piece of coarse sandpaper wrapped around a short chunk of 2x4 will do the trick in next to no time.

Then, lay glass cloth on the outside and coat it with epoxy resin. Build up two or three succesive thin coats of resin to smooth over the pattern of the fiberglass cloth's texture (hide or fill the weave) then sand lightly, paint, and paddle.

Don't worry about disolving out the plastic foam. With a sit-on-top design that interior foam simply adds some strength as a very small sacrifice in weight. With the exception of cutting out the centers of the panels for your seat, this is a process that is similar to one used for creating surfboards.

Hope this helps.

PGJ

Messages In This Thread

A new method to build a kayak.......???
Mark F -- 9/8/2001, 1:26 am
Great idea for a fast sit-on-top kayak
Paul G. Jacobson -- 9/9/2001, 11:05 pm
Re: A new method to build a kayak.......???
John Monfoe -- 9/9/2001, 8:09 am
Use thin foam and leave it in place.
Paul G. Jacobson -- 9/9/2001, 11:37 pm
Re: Foam & glass Website
Dave Houser -- 9/10/2001, 3:04 pm
Re: Another one
Shawn Baker -- 9/10/2001, 3:34 pm
Why not ;) stripper with strips cut from foam :b ? *NM*
risto -- 9/10/2001, 12:40 pm
Peter Van Dyne did this 30 years ago
Craig Bumgarner -- 9/12/2001, 11:51 am
so, nothing new under the sun :) !
risto -- 9/13/2001, 10:27 am
Re: A new method to build a kayak.......???
tg -- 9/8/2001, 11:39 am
Re: A new method to build a kayak.......???
Mike Scarborough -- 9/8/2001, 3:17 pm
Re: A new method to build a kayak.......???
Tapio Manner -- 9/8/2001, 3:23 pm
Thanks everyone I've had this idea for years...
Mark F -- 9/8/2001, 11:09 pm
Re: Thanks everyone I've had this idea for years..
100GRIT -- 9/9/2001, 7:34 am
Re: Thanks everyone I've had this idea for years..
Rehd -- 9/9/2001, 12:05 am
Re: A new method to build a kayak.......???
Tapio Manner -- 9/8/2001, 4:11 am