Stitch and Glue Kayak

Although I had never actually kayaked before, one day I decided to make a stitch and glue kayak. For a non-kayaker I'm not sure why, but it had to do with a rowing class I had taken once, and I wanted to get out on the water on my own boat. Also, building a rowing shell seemed difficult, better to start with a kayak.

For those of you who don't know, stitch and glue is a well established method of building all kinds of boats. It involves cutting plywood into the right shapes, stitching the shapes together with wire, and then permanently gluing the whole thing up. A quick web search will yield loads of info about it.

There are some really nice kayak building kits out there, and you will definitely get better results than I did with a kit, but I'm pretty happy with how my kayak turned out. Also the kits can be a little pricey and I am going cheap. These online sites also sell plans which are much cheaper than the kits: Chesapeake Light Craft, Pygmy Boats, One Ocean Kayaks, and Shearwater Boats.

There's a few free kayak plans on the internet. There's one called the Guillemot and there may be some here, here, and here, but I chose the Sqeedunk C-16 because it looks a little easier to assemble. Now these aren't exactly plans, they're really just points you mark out on the plywood, then play a interesting game of connect the dots.

Another option for the true DIY'er is to design your own kayak using FreeShip, DelftShip, or your favorite 3D CAD software. Just be sure it is capable of unfolding curved surfaces, so you can take the curved panels you design and flatten them out for the plywood. A word of warning: CAD software typically has a steep learning curve. You may end up spending a lot of time working at the computer.

For materials, you will need some thin plywood. Everyone in the kayak biz will tell you to use okoume marine grade plywood, and they are right. However, since I'm going cheap and I just want a recreational kayak I can play around in rather than a serious sea kayak, I bought two nice looking lauan 4'x8' pieces at Home Depot. They are sometimes called door skin and are about 1/8 in. thick. Here's a tip, use a flashlight to shine light thru the plywood and look for gaps or voids in the middle. Voids are bad.

To start off with I bought, 30 ft of 6 oz. fiberglass cloth, a gallon of epoxy resin and half gallon of hardener from this online site. I also bought several feet of solid copper wire at the hardware store. It was red and white 20 gauge wire for antennas I think. Make sure it's solid, stranded wire will not work.

This was a really long project, it took me around 8 months, but there were weeks that I didn't get any work done. If working on it full time, it could be done in less than a month.

For tools, I used a coping saw and key hole saw to cut the plywood although some people recommend the japanese style pull saws. A power circular sander is a must. I used many a 60 grit sanding disc. You will also need a seemingly endless supply of sand paper, disposable brushes, and latex gloves. Other tools: rasp, carpenters square, drill, utility knife, safety glasses, pliers, etc.

Step 1: Scarf the sheets

"Aaarrgh, scarf the sheets, ye scallywag" sounds like a cryptic phrase a pirate would say, but it's apparently a method of attaching two pieces of plywood together. The idea here is to sand the ends of the boards down to a thin blade-like edge, then glue it flat onto another blade-like edge. If done well this gives the illusion of one continuous grain of wood running from one 4x8 ft. sheet to the other.

The boat I chose to build is a 16 footer, but that's way more boat than I need and I don't want to store a 16 foot boat. Also it would require attaching three 4x8 ft. pieces of plywood together.  I decided to shrink the boat down to a more manageable size, but more on that later. Shrinking allowed me to attach just two plywood sheets together.

To create the edge, I took a 2x4 board, and placed a scrap piece of plywood on top of it. Then I placed one sheet pretty side up on to the stack, and the other sheet pretty side down. This way the pretty side doesn't get damaged during the scraping and sanding. The boards are offset by 2 inches then I placed blue tape 2 inches from the edge of the top sheet to let me know that I should not cut into that part. I used a C clamp to keep the stack from moving. Then rasp and sand it down to a nice smooth slope.

I kept as much saw dust as possible to thicken the epoxy later in the build. The thickened epoxy is useful for squishing into the corners for a stronger joint.

Glue it together. I used water resistant wood glue because I was waiting for the epoxy to arrive, but I regret it. Using epoxy will blend in better with the later epoxy coatings. I swept the floor and laid down some plastic wrap to avoid gluing the sheets to the ground. I then placed the bottom sheet down and applied glue. Next came the top sheet followed by another layer of plastic wrap. Finally I topped it all off with scrap plywood and weights to make a tight bond. Let it dry for a day and you should have one long 4x16ish sheet of plywood.

Comments

[CamWaite]

Tres bien! Just a quick question, how did you cut the cockpit and how much did it cost?

[LongToe]

Thanks! I drew the cockpit outline using a couple different sized buckets and a straight edge, then cut it out with a keyhole saw. To get the initial hole I probably used a dremel or drill. I can't remember. I didn't keep very good track of the cost, but it was probably around $300 - $400. The epoxy and fiberglass cloth were the most expensive parts.

[CamWaite]

Thanks, might be a while before I can afford that =[

[TANZMEISTER]

You can save a ton of money if you get 2in fiberglass tape instead of cloth.  The added strength of the cloth isn't needed if you put a second layer of the doorskin where your weight sits.  I usually do 2 layers of ply under my bum with the seat fiberglassed to the the sidwalls.

  You will still need to coat everything in the epoxy to properly seal it.

[Science Swine]

How many gallons of epoxy did you use? It seems like you would need a ton of it in fiberglassing alone.

[LongToe]

Good question. I bought a 1.5 gallon set, then towards the end of the build I bought another one, but I only used about half of it. So I think I used about 2 1/4 gal. but I also wasted epoxy by making mistakes and occasionally preparing too much. Someone more experienced in epoxy and fiberglassing could make it using a lot less epoxy.

[Science Swine]

One more question, how did you read the plans on the website. I want to build a 13-14 foot but I am not sure how to read the plans or how to shorten it without "messing up" the middle of the boat.

[LongToe]

I kept the length between 60" and 108" the same and shrank the ends. Since most the stations are about 12" apart I reduced it to 10" that's about 83%. So for the stations that aren't 12" I just multiplied it by .83. I then rewrote the tables with the modified stations, and started sketching it out on cardboard. It's not a perfectly proportional change but I took the risk and ended up doing a little trimming of the plywood during the stitch part. I hope that helps.

[LongToe]

Also, since the hull bottom is significantly shorter than other panels, I think I made the distance between station 48 and 60 11", the distance between 96 and 108 11" and ones in the middle 12"

[Darkfish]

If you could find the time to do an instructable on reading and plotting the points i feel it would help many of us inspired, future boat builders ;)

[cephastaphile]

I built a CLC stitch and sew kayak some years ago and used a different method of joining the sheets.Instead of scarfing the edges,I cut a zig zag pattern in the ends of the sheets and butted then together with epoxy.They were weighed down on a piece of glass which was perfectly flat and another on top.The glued bits were covered with cling film to stop the plywood sticking to the glass.Lateral pressure was applied to both sheets when they were butted together and kept in place by temporary nailing.The finished effect looks great.I fact I liked the effect so much I joined the deck pieces that way and finished the deck with varnish to show it off.For those of you timorous about the dark art of scarfing,(as I was),I commend this alternative to you.As far as I can tell no structural strength is lost.My boat is still floating and in one piece.

[LongToe]

That sounds great! You should post some pictures or write up an instructable. I would like to see the results.

[pajamas786]

i love what you built because it is beautiful. i know it took a long time but this is something your grandchildren may use. anyway, amazing. you're a real boat builder

[LongToe]

Thanks!

[clind98]

Wow that is amazing i found the plans for your kayak and have a few questions.

first
i don't understand how to read the tables (as in what does top edge bottom edge mean exactly how do you know whats what)

second

how long did it take for you to build the cardboard mock up?

and third

how did you make your bungee fasteners?


Thanks

[LongToe]

Thanks!
For drawing the kayak out the table is all in inches. It might help to use some graph paper. The station is the distance from the left, and top edge and bottom edge are relative to where the edge is on the boat. So the top edge will be above the bottom edge when the boat is right side up.
I think I did the cardboard mock up in a few hours although I had been reading the instructions and thinking about it for a few days. Just mark out the dots, connect the lines and cut out the shapes. Then glue or tape them together.
There's a paragraph at the end where I talk about the bungee fasteners. I think they are called padeyes, and mine are made of scrap plywood glued together, drilled for a hole, and shaped smooth.

[clind98]

Wow

Ok that really helped but left me with one more question
When you say it's all relitive how would you measure that like do you measure from the top/bottom of the plywood or from where the boat is

Thanks again!!

Ps
Sorry for the beginner questions but I had never seen anything like this until yesterday

Thanks

[LongToe]

Yes, you measure from the edge of the plywood. Try drawing out the shapes on a piece of paper. The edge of the paper is straight so measure to the right then measure up. Place one dot for the bottom edge then one dot higher up for the top edge. They should start to look like the shapes that are in the pictures when you connect the dots. Good luck!

[RustyVW]

First, thank you, nice job! Now I got a question: I laid out the offsets for the hull bottom on butcher paper. Some ofsets have a + or - after them. Station 0 and 179 bottom have nothing but a -. What do they mean? And your photo's show a radius on the ends. How did you figure them?

[LongToe]

Thanks! The + and - mean 1/32 more or 1/32 less than the given amount. As for the radius I just used a flexible piece of plastic as a curved edge to draw a curve between the stations. Keep in mind that the hull side panels should have two corners on each end. In the picture you can see it curved, but I had to go back later and cut the curve off.

[Zaroo]

I want to make one.I like it very much.

[LongToe]

Thanks! If you make one be sure to post it online. Good luck.

[Zaroo]

I　have a few questions:

First of all, i have already designed the ship body which i want with freeship.But i didn't figure out how to develop each curved surface.Does it need the assistance of CAD?
Secondly, how could you cut the plywood into shapes which are needed? By craft or by water-jet?
Thirdly, the maximum size of my plywood is 1220X2440mm. It is necessary to be adhered with yours.I would like to know how to assure the rubber-determination of adhesion?
Forthly, i am thinking about to replace the plywood by PVC board and make another 4 Bulkhead inside the cabin intended to reinforce the strength of shipping.In this case, the method with fiberglass could be omitted. What's your opinion?

Happy Spring Festival (Chinese New Year)and may you be prosperous!

[LongToe]

I can't answer your questions but I'll try.
I didn't use Freeship, but from what I understand a surface is developable when it bends in only one direction. The tool should be able to show that. Check Developable in the layer properties. Also, check out section "13.4 Develop plates" of the Freeship Manual 2.6
For cutting the plywood I used a hand coping saw. A more high tech solution would probably work, but subjecting the unprotected plywood to water might cause some damage.
I suggest connecting 2 1220X2440mm sheets of plywood using the scarf method. With epoxy the adhesion is very strong.
A PVC board for a bulkhead might work, but be sure the epoxy can stick to it. Since it is nonproous it might not work. I didn't fiberglass my bulkhead, it's just painted with epoxy and varnish.
Good Luck with your build!

[Zaroo]

Thank you, I already know how to expand the surface.
I will try to make a boat with other materials, but I just graduated from university, need to work, do not have enough time to complete, so some time before this site posted.

[mikesnyd]

Do you have some blue print type image for the basic layout for the panels? So I can make the cardboard one first.

[LongToe]

No, sorry I don't have anything like that. It is similar to the Guillemot design however, they both have 8 panels just slightly different shapes.
http://www.guillemot-kayaks.com/guillemot/information/kayak_building/stitch_and_glue_construction/free_stitch_and_glue_kayak_plans

[mikesnyd]

Oh i realized you put a link back in step one that had the off sets and rough panel shapes. I wish i had of checked all your links rather then posting this redundant question. I was able to take the off sets given on the website and draw it in sketch-up. Then i scaled it down to a 15.5 ft size and took myself some new off sets. I was planning on buying a kayak but i think this is gonna save me and look way better. Thanks for your inspiring ible.

[mdshann]

Maybe a cardboard template would have made the bulkhead easier to fit. This is a very nice boat though, my Dad and brother built 2 of them a couple of years ago, they did it in the basement and didn't realize that they would not be able to turn them at the top of the steps to get them out of the house! Luckily there is a window across from the steps they had to take it out to get the boats out.

[jackg]

super job, very nice, looks good in the water, i'll bet it is easy to paddle,

be proud that you made it by yourself.

thanks for the instructable

[Mig Welder]

I must say, ingenious little PVC clamps!

[rt3tech]

Brilliant! I started out ruminating about a canoe, but I found this and the plan changed. Hopefully I'll have one finished before summer is over. Thanks!

[itsandbits1]

great job on the clamps; and not because I have to say so because of the constructive criticism policy, which is pure stupidity, go ahead, ban me

[T.Rockwell]

BEAUTIFUL!!!
and nice ible too!
approximately how much does she weigh?

[LongToe]

Thanks! She's about 37 lbs.

[Nate95]

The site with the c-16 plans is gone. Are there any other sites with these plans?

[LongToe]

That's too bad, that was a pretty good site. I found an archived version here:
http://web.archive.org/web/20070314064231/www.squeedunk.com/c-16.htm

[Nate95]

Thanks a lot !

[OruKun]

What did you stitch it with?

[LongToe]

It's temporarily stitched with copper wire then glued in place.