Picture of Making a Plywood Kayak
The Jupiter Point series of kayak designs are intended as easy-to-build, fun-to-paddle, versatile collection of kayaks. With a simple 3-panel hull and unique 3-panel deck, the boats are quick to assemble, have a lot of character and perform very well. Plans are currently available for Ganymede a 13' recreational kayak that uses 3 sheets of plywood. You can download free plans from my website: http://bit.ly/xde8Bz. I've also drawn it up as a 7' childs boat I call "Io" that can be made out of a single sheet of plywood. The free plans for this are also available. Chesapeake Light Craft makes high quality boat kits they offer a complete kit for Ganymede if you don't want to scrounge materials on your own.
The construction is done with a technique called “stitch-and-glue” and is built from thin plywood. The stitch-and-glue (S&G) method use plywood panels cut to shape that are temporarily wired together with copper wire. This wire is the “stitches”. With the panels held in their intended shape with the wire the plywood is permanently glued together. The wires are removed and the whole thing is covered in a layer of fiberglass cloth and the cloth is saturated with epoxy resin to make it strong and waterproof.
The preferred material for this construction is 4 mm thick okoume marine plywood, covered with a 6-ounce per square yard fiberglass cloth coated with an epoxy resin. This will provide the strongest, longest lasting construction, but if you are strapped for cash, you can substitute lauan “door-skin” for the okoume and polyester resin for the epoxy. Lauan is apt to have gaps in the interior veneers that make the plywood. These gaps can weaken the material and may accumulate condensation leading to rot, but with a little care in building and storage when you are done lauan can make a nice boat. The description of techniques in these instruction assume epoxy resin, you may need to adjust your technique if you opt to use polyester.
tinpusher1 year ago
Brilliant! Thank you for sharing your expertise. Someone below was asking about the cost of this build. What do you think would be the feasibility of building this from coroplast? The glassing could conceivably be eliminated entirely.
pchavesm1 year ago
could anybody if you can use polyurethane glue or any other glue in the step 4 (filling the plywood)?
thanks for the plans, the instructions (and the books)
timmer5943 years ago
Could you give an idea of what this would cost to build? I'm afraid the f/g would be too expensive for me. Thanks though,
Guillemot (author)  timmer5943 years ago
Fiberglass runs from about $5 to $7 per yard. You need about 18 yards. If you keep your eye out on ebay you can find off cuts quite cheap.

Another option if you are willing to go with alternatives is: just about any cloth can be wet out with resin and bonded to wood to provide reinforcement. So old cotton sheets or muslin could conceivably be used. Historically boats have been covered with canvas to good effect.

If you are looking to go really alternative, consider using tri-wall cardboard instead of wood then reinforced with fiberglass or muslin. You would want to make sure that all the edges of the corrugation were well sealed. But if you are willing to think "outside the box" a bit, there are many alternatives.

Lastly, the epoxy resin could be substituted with polyester resin, or going further afield diluting a polyvinyl acetate glue such as titebond or titebond III could be create a workable alternative with a little experimentation.

thank you for this generous instructable!
The offsets are very clear and logical.

Can you tell us what the beautiful red plywood was used on the child's kayak?
Or is it a red stain over a light-coloured ply?
I think it's just delicious!

Uptonb3 years ago
Congrats on being a finalist, and good luck!
vann_solo3 years ago
I tried to download the .pdf file but it indicates it to be corrupted.
Guillemot (author)  vann_solo3 years ago
I just tried downloading and it came through without any problem.
The plans at http://www.guillemot-kayaks.com/guillemot/files/Ganymede_Offsets.pdf are also showing corrupt for me.
Guillemot (author)  bacterium3 years ago
I tried again by copying and pasting the above URL and it still worked, but I have opened the PDF in Acrobat Pro 10 and re-saved and uploaded the new file. Please let me know if there are still problems
Okay, it seems to work in Chrome. I was trying to download it and open it with Acrobat 9 and Foxit and it didn't work. Thank you. And sorry for the hassle
verrillc3 years ago
Awesome Instructable!
Is the 7' child's kayak plan also free on your website?
I could not locate it.
I've dreamed of building one of the Chesapeake Light Craft kits for years.
Your Instructable may be the inspiration I need to actually do it.
Guillemot (author)  verrillc3 years ago
I just posted the free plans for the kid's kayak. I call the design Io after another moon of Jupiter. Chesapeake Light Craft has the files to cut an Io kit as well.
Hi and thanks fore this instructablues.
I am going to make the Io fore my yongest son.
How much fiberglas and epoxy you think I need fore Io?

I have made 2 boats: Ponnt Bennet 17,5 fore  and Chesapeake 14 fore my 11 year old son.

Now this winter I am going to make the 14 Foot Great Auk (got the plans from CLC) fore my 8 year old son but after seeing this instructabule I am first going to make Io for my 5 year old son

Bulding kayaks is realy fun... :)
Io makes sense now that you point it out (I thought it was Lo.)
Io and Ganymede are now bringing back memories of Astronomy 101.
skiedra3 years ago
That is an awesome and well documented build! Great inspiration!
mjursic3 years ago
I think I can do this! Thanks! Can you tell me the load limit on one of these? I myself am 240 lbs. WOuld it hold me?
Guillemot (author)  mjursic3 years ago
I designed Ganymede to hold up to about 300 lbs. It won't be the most spritely boat with that much weight, but it will float with some room to spare. If you are a really top-heavy body-builder type it might be a little unstable.
Nice job but I prefer to call the stuff "ookie pucky". Dookie Schmutz would be a little thicker.
lobo0x73 years ago
great boat and awesome instructable

gnach3 years ago
Brilliant instructable. It's a terrific primer and we've learned about "dookie schmutz". Thanks a million.
friger3 years ago
Excellent job, I have studied your designs in the past, we're talking 20 years ago. For those who don't know, Guillemont is a bit of a celebrity in the wood kayak building world. It's an honor to see your work once again.
Lovely instructables, thanks a lot for sharing!
I will use some of your techniques for my next project :)
ilpug3 years ago
Amazing work!