Introduction: Stich & Glue Plywood Canoe

Picture of Stich & Glue Plywood Canoe

Hi!

I developed the urge to build my own canoe/kayak. It took a while to get the courage for the undertaking, and my research took me down several possible avenues. Eventually, with the tools, time and money I had on hand, I settled on a "stitch & glue" building method using plywood, fibreglass and varnish.

This is the story of how I did it. Took me four months of about an hour per day, and a couple of weekend days. The total length of the boat is just under 4 meters.

The end result is a beautiful (to my mind at least) piece of watercraft that I hope will bring joy to my family and friends for a long time to come.

I can't claim to be an expert on the materials and processes I used, and pro's and experts will probably spot many mistakes. But, I finished it, and it works. So I love it.

Perhaps you will also take your heart in your hands and embark on a build journey similar to this.

Good luck!

Step 1: Getting the Dimensions

Picture of Getting the Dimensions

This was the plan I drew up in my 3D animation software. It is a quarter of the plan, and this one quarter is lofted (transferred by measurements & pencil) onto one half of a 1.2m by 2.4m sheet of 4mm plywood. The measurements are in centimeters and meters.

I printed these plans in miniature and constructed four little paper canoes before I was happy with the measurements. Then it was on to getting the plywood sheets joined and cut.

Step 2: Skills Required

Picture of Skills Required

I decided to add this step because it is easy for me to forget that we all have our own skills sets, and that I might inadvertently assume understanding of a particular skill for this build.

For the biggest part I am a "maker"-type personality. It seems that in the twenty-first century we can assume this name for ourselves as representatives of a group of people that are tinkerers, self-builders, DIY enthusiasts... call us what you will, but it seems the newest logical grouping might be called "makers". As such we rely on a batch of skills that have often mostly been learnt as we went along - not necessarily taught.

Fiberglass & resin:

Professional builders take note: I respect your skills and experience. Feel free to make comments and give advice... but be nice! This is not a technical course on composite building techniques - it is a quick instructable.

The biggest skill required for this build as far as I am concerned, is the patience to work with fiberglass. Not the glassing itself - the glassing is a process of putting down fiber and smearing on resin - but the patience to take it a step at a time. Rushing the process results in bad looking fiberglass and unnecessary bumps and other nasty things.

Read the instructions and follow advice:

The hardening of the resin is a chemical reaction - not air-drying. So heat is required. If your work area is too cold the resin simply won't cure. Read up on what the curing temperatures are and make plans. If you need to switch on heaters, then do that. If you want to use a heat gun to "kick" the hardener into action, do so. (This is a boat, not an airplane - a failure in the composite in an airplane is orders of magnitude more critical than failure in a flat-water canoe so this advice would be "not good" for airplane construction.)

Mixing proportions for fiberglass is sort of really really important. Epoxy is more sensitive to errors in ratio, but polyester resin can be too brittle if cured too quickly. I found that a small plastic teaspoon or two of hardener per paper cup of polyester resin would always work. Closer to two teaspoons on colder days, and one teaspoon on warm days. The amount of hardener also influences your working time, so perhaps having the patience to test what will work best in your environment is a good idea? Remember... patience is you biggest required skill.

Don't try to mix an eighth of a cup or similar "small" quantities. The mixing ratio is too difficult to get right. Best to wait till you have a reason to mix at least half a cup of resin. Then do two or more things with it.

Problem solving resin not curing:

If you have ever worked with polyester resin and mixed a batch that didn't cure... well... it's a crappy mess. I've had that happen, and honestly I don't know what the best course of action would be. You could do any of the following:

  • If it didn't cure at all, pull the fiber matt off and try to clean the surface with acetone. Can't guarantee it'll work, but if it does it'll save time over trying anything else.
  • If it hardens but remains tacky to the touch (as in you can just see your fingerprints), don't worry. Go for the next layer. If it's the last layer, then varnish over it. The varnish will harden and you can carry on with the next layers of varnish.
  • If partly cured try brushing on a layer of resin. If you're lucky the hardener will also kick the previous batch of resin. Best to try and apply additional heat.
  • Use a heat gun to kick the reaction. Sometime a certain spot won't cure while the rest does. Heat gun it and see if it works. I suppose a hair dryer would have a similar effect.
  • Put it out in the sun if that is an option. But it must be a warm summer sun. Winter sun probably won't work. :-)

Top coat or Gel coat:

These two products can be used as an outer layer for the glass, instead of or with varnish. There are many tutorials on Youtube on how to use it. Watch a couple and decide for yourself.

These two products are a lot hardier, harder and resistant to abuse than varnish. But they are more difficult to finish off with than varnish.

I bought both gel coat and top coat. Gel coat should be used on molded products where you brush the gel coat into the mold, then glass on top of it. The chemical composition of the gel coat makes something move through something and makes particles migrate to the outer layer and that helps it harden... whatever. Gel coat is meant for molds. It has a thick jelly-like consistency and is hard to work with. I found that gel coat worked over the fiberglass and it hardened perfectly well. But that was a "guerrilla" tactic.

Top coat is purportedly the correct outer layer for fiberglass (apart from gel coat or varnish or paint). The top coat I bought was more runny than the gel coat. I used it once and it remained tacky. So I decided to rather use the gel coat as it hardened perfectly on the first try. The top coat is still in my shelf. I'll use it somewhere else.

These two types of coatings get really hard. Like, as in, REALLY hard. Harder than the fiberglass - therefor the reason for using it as an outer layer. Don't be afraid to use really heavy grit sandpaper.

Sandpaper:

I suppose I don't understand polyester resin. Right? Because every time I needed to sand a layer I would first have spend some time sanding off a sticky, waxy outer layer. It gummed up the sandpaper within 30 seconds. So that caused me to lose a lot of sandpaper. Right at the end I saw that when the gumming starts and the streaks appear on the fiberglass surface, I could use a dishwashing metal sponge (proper name for it?) to scrape off the gunk. That would've saved a few meters of sandpaper I think...

For the biggest part I used 80-grit sandpaper that I can buy in rolls from the hardware store. No use making suggestions here... I used it with sanding blocks, without sanding blocks, held between two fingers, held flat by my whole hand... which ever way I could hold on to it.

Gloves:

My advice: buy a lot of latex surgical gloves. I've read somewhere that the kind with powder on might cause epoxy not to harden/cure. Don't know about that, but take it as a heads up! Didn't read about anything like that for polyester resin, but perhaps it's best to play safe.

I was sometimes able to use a glove twice. I would pull the glove off my hand so that it was inverted. Then when I wanted to reuse it I would turn it the right side out and blow into it to get the fingers out the right way. However, they are so cheap that it really didn't make a dent in the budget if I threw it away.

I used the gloves when sanding as well, not just when laying down glass.

Oh yes, and then there's...

Sawing, measuring (in reverse order it works better), taping, strapping, gauging, painting, electric sanding, shaping, waiting, budgeting... etc. Do the best with what you have. Often I had to force myself to "just do it" (thanks NIKE).

Step 3: Setting Up the Plywood Sheets

Picture of Setting Up the Plywood Sheets

The wood:

This build required two sheets of plywood (1.2m X 2.4m) joined end to end or "butt-joined" (I think?). So first step was to cut a strip of wood from the end of one of the sheets to overlay and glue to the join between the two sheets.

Glue:

The "stitch & glue" building technique has been around for hundreds of years (I'm guessing thousands) and relies on joining panels with stitches of some kind or other, and then reinforcing the seams with glue.

In most cases these days two part epoxy resin is used. I have worked with epoxy building model airplanes, but in this case, and in these volumes, my budget simply didn't allow for epoxy resin. So I reasoned that polyester resin & fibreglass have been a canoe/boat building material for a long time, so I settled on using that. In the end I think I used six liters of polyester resin.

From what I understand epoxy resin is a much better "glue", and that it may last longer. But for this build, it was not an option. Also, the marine varnish I added at the end provides the necessary UV protection. Withouth the varnish, both the epoxy and polyester resin would degrade faster in direct sunlight.

The join:

I smeared thickened resin (thickened with micro balloons) around the joint, then stuck the joining strip over the joint, and placed some heavy stuff on top... and it was only about 30% effective! What a disaster. Even with the weights the one end of the joint lifted up, and I was set up for a lot of sanding and alternative plans later in the job. The two sheets of plywood were offset in the joint, meaning that later on I would have to fill up the sides of the joint to have a smooth hull. It sucks, but I couldn't buy more sheets. So on I went!

Blooper:

Have a look at the last image to see the bad join. The joint was nonetheless stable and strong, and I felt confident to forge ahead, knowing full well that there would come a time of pain...

Step 4: Lofting

Picture of Lofting

I drew a (cross) center line along the length of the plywood sheet, and across the center join. Then I used that as my zero point. From there I measured and marked all the points based on my computer design.

I screwed short sharp whiteboard screws into the marked points. Then I used a thin strip of wood to allow me to draw smooth curves by pressing the wood to conform to the line indicated by the screws. It worked really well.

Step 5: Cutting the Plywood Sheet for the Bottom and Side of the Canoe

Picture of Cutting the Plywood Sheet for the Bottom and Side of the Canoe

The plywood is thin, so I had to use quite a number of supports to hold the thin strips after it was cut.

Apparently the accuracy of the cuts are not that important, as this technique is very forgiving by allowing gaps between the assembled pieces of up to 10mm. In this build my parts lined up and I didn't push the envelope on that aspect. I think the biggest gap I had between boards was under 7mm.

To reduce splitting and ragged edges on the plywood I used a metal cutting blade on my jigsaw with fine teeth. This worked reasonably well.

Step 6: Dry Fitting the Parts

Picture of Dry Fitting the Parts

Using duct tape I managed to get all the parts in place, and I was very happy, but amazed, to see that there were no major cockups or errors in my design.

I did feel that the top edge of the boat was too high, and decided to put a curve into the top edge.

Eyeballing it convinced me that a dip of 11cm in the center of the boat would give me a pleasing line for the top edge.

I took the off the two top panels and, using a thin, long piece of wood, I marked out a curve that came down 11cm from the top edge. I cut this with the jigsaw by pressing together the two panels. This was a deviation from the plans.

A "dip" in the top panel of between 11cm and 5cm would work for this design.

Step 7: Making the Cuts Straight and Smooth

Picture of Making the Cuts Straight and Smooth

I only spent a couple of minutes planing and sanding the edges of the panels. My initial jigsaw cuts were accurate enough not to warrant a lot of time before starting the "stitching" process.

I did place the panels on top of each other to coax them into an acceptable form of symmetry with the gentle planing and sanding.

Step 8: Stitching the Panels

Picture of Stitching the Panels

I opted to use cable ties to stitch the panels together by drilling a couple of small holes along the seams at matching points. But honestly... this irritated me.

So I took a shortcut and used the hot glue gun to position and hold the panels together. Burnt my finger, but it went a lot faster. I knew that I might struggle to get the glue off at a later stage, but I figured that glue was soft to sand, or pretty simple to scrape off with a chisel. (I figured wrong of course - hot glue gets hots from friction when you sand it. Then it just becomes glue while you try to sand it)

I made a proper mistake by thinking that I can hot glue sticks in place to spread the sides of the boat. When I finally added the top side panels, the spreaders didn't work and I had to cut them off. A sense of foreboding arrived when the hot glue held so tight that I could not get the spreaders out and had to saw them off short.

I didn't like the way that the top sides of the canoe sagged and spread apart in the middle so I hot glued two long sticks along the sides of the boat to make it look better to my eye. This proved to be a good approach later on, as the boat kept a pleasing shape after the resin was added to the seams.

Last step was to check whether the boat was symmetrical and whether the bow was 100% upright.

Step 9: Taping Up the Stitches

Picture of Taping Up the Stitches

After doing the cable tie stitches and hot glue joins it was necessary to tape up all the seams in order to prevent the glue from running out in the next step of construction.

When the panels are together and the tape goes on it really starts looking like a sleek design, so the build itself is an inspiring one!

Step 10: Adding Glue to the Seams - Inside the Boat First

Picture of Adding Glue to the Seams - Inside the Boat First

I mixed up some polyester resin (I was using a scale at that point) thickened with fine sawdust from my orbital sander. It worked well, except that it was dark. I read somewhere that some shops sell color graded thickener or "wood flour". But one look out the window at Table Mountain in the distance assured me that I still live in Africa, and yes, I would probably find wood flour somewhere, but instead of going off on an expedition, I was happy to use my own "wood flour"... Had no problem with it either and I will probably do the same in the future.

I didn't have much luck using a syringe to squeeze the resin along the seams. In the end it was much simpler to use a wooden tongue depressor and smear it roughly, then use the round tip of the stick to make a neat rounded glue seam.

At this point I made my biggest time wasting mistake.... I put the glue on way too thin. For some or other reason I thought that a neat thin line of glue in the joint was good. That was simply a bad thought and I suggest making a nice thick seam with the thickened resin.

After a while I switched to mixing the resin and hardener in the ratio of one to two small plastic teaspoons of hardener to one paper cup of resin. Polyester resin and hardener eats some plastics, so that little yoghurt holder in the picture was only used once...

Step 11: And So Starts the Sanding...

Picture of And So Starts the Sanding...

Sanding:

Nothing to say about sanding... it takes a long time, and most often the resin has a sticky waxy outer layer that gums up the first rolls of sandpaper. Be sure that once you start seeing white dust the happiness level increases.

I added more resin along all the seams to thicken them up after the first round of sanding Could have save myself a couple of hours in the process by simply applying the first batch a lot thicker.

Fibreglass tape:

I bought fibreglass tape to glue down over the seams next. You can just make out the fibreglass tape over the bottom seam in some of the pictures. I bought a thick tape that was difficult to saturate with the resin. If there is ever a next time I will go with strips of fibreglass tissue, or strips of medium weight cloth (I define "medium weight" as the thickest cloth that will stay in place on the curve after saturating it with resin).

Step 12: Fibreglassing the Inside of the Hull

Picture of Fibreglassing the Inside of the Hull

I have been having experience with fibreglass for the last 25 years, so it wasn't wholly new to me. I am always afraid that the resin won't cure properly. Luckily on this build it cured sufficiently every time.

I glassed the two insides of the hull first. The idea was to get the shape as rigidly fixed as soon as possible. I wanted to remove the two side pieces of wood that was preventing the canoe from bowing outwards as early on in the build as possible. They were going to be in the way when I started glueing the gunwhales/gunnels.

Step 13: Cutting the "hold" Bulkheads

Picture of Cutting the "hold" Bulkheads

I made a quick little angled tool to help me draw the bulkheads for the front and aft holds. The idea was to cut holes in the boards and add watertight lids (can't think of the correct "maritime" term now for those lids).

I Googl'd and found some Cape Town suppliers, but I was happy with buying the biggest plastic containers I could find to cut up and use for the holds.

Step 14: Getting the Seats Just Right...

Picture of Getting the Seats Just Right...

I read quite a bit on how other people built their boats, and from the start I picked up that these canoes (like all canoes) can be "tippy".... that is to say that you constantly tip over if you are not used to paddling in a canoe.

One of the chief aggravating factors in this aspect is the height of your body above the floor of the canoe. The lower down you are, the less "tippy" the whole process of paddling becomes.

BUT I wanted to sit comfortably. So I stacked blocks of wood to measure the minimum height at which I would be comfortable. I found this to be a seat height of 14cm above the floor of the canoe. This was just about halfway up along the height of the canoe side. Considering that most racing canoes place you less than 5cm above the floor of the canoe in a padded seat in which you sink down further, my 14cm was bound to have an effect.

In any case... onwards... I shaped the two seats based on their positions along the curved sides of the canoe. Since this was a 2-person canoe/kayak/boat I had to figure how much space I could give each person by positioning the seats correctly, as well as consider the center of balance of the boat along it's length.

In the end each occupant has 90cm of legroom from the back of their seat to the tip of their toes. This is a very comfortable measurement. In addition the taller person sitting at the back could have their feet underneath the front seat for additional leg room.

Step 15: Building the Seats

Picture of Building the Seats

Each seat was built from the same 4mm plywood as the rest of the boat, with three supporting pieces of pine wood. I opted to close up the bottom of the seats with more plywood.

The seats were then covered with glass tissue and a layer of topcoat. I couldn't get the topcoat on smooth enough so I sanded it smooth and then left it so that I could add varnish on top when I did the final varnish on the whole of the boat.

In the pictures you may see a couple of dry spots in the fibreglass cloth on the hull... Most of those were sanded/cut out and filled up towards the end. Again... I dont' really want to talk about sanding...

Step 16: Installing the Seat Supports

Picture of Installing the Seat Supports

I considered the option of not fitting permanent seats, but rejected that eventually. Couple of reasons but I can't remember why right now... (In review I realized that I didn't want to add a "thwart" or cross-beam to the boat. The fixed seats meant I didn't have to do it)

To position the seat supports I used a 14cm high block with a water level to mark the top and bottom position of each seat. Then I planed the wood supports so that the seat would sit squarely on them. The seat supports are fastened to the side of the hull, meaning that they are set at an angle. Thus the need to plane them.

Initially I screwed the supports to the hull. Soon they were fixed in place with resin and wood flour glue. Then I removed the screws.

Step 17: Adding Deck Supports

Picture of Adding Deck Supports

Since I wanted two holds, front and aft, I needed bow and stern decks. Those needed to be curved, of course... just for the look of things.

So I first cut supports that matched the curve of the bulkheads, and then I transferred the curve to a shorter support piece halfway between the tip and the bulkhead. Glued and screwed those in place. The bulkheads were still loose and would only be installed once the decks had been installed and glued from the inside.

The build process wasn't always in the order in which I am presenting it here. In the pictures above you can see the first of the gunwhale strips already in place.

Step 18: Glueing the Decks

Picture of Glueing the Decks

I held down pieces of plywood over the deck areas, made a rough trace, then cut them out before glueing the decks onto the boat.

I mixed thicked resin and generously coated the gunwhale and deck supports before clamping the deck at the widest point, and then systematically strapping the deck to the hull as tightly as I could manage. I'm guessing there might be something wrong with this approach, but on this one I was shooting from the hip.

I was very nervous about doing the decks, but it worked out really well. The last picture is a picture of the inside of the hold before I added additional epoxy. There was ample space to work inside the hold with the boat turned upside down, so I was able to add a thick bead of thickened resin along the entire length of the underside of the decks.

Step 19: Glueing the Gunwhales

Picture of Glueing the Gunwhales

The gunwhales/gunnels for this boat consisted of three additional strips of wood being add to each side of the boat.

On the inside of the boat I first added a rectangular cross section strip that ran from hold bulkhead to hold bulkhead (i.e. NOT the entire length of the boat) with a half round pine strip on top (budget was an issue on this build).

On the outside of the boat I added a half round pine strip that DID run the full length of the boat.

In order to get the length I needed for the pin strips on the outside I need to splice & glue them together.

Then it was on to glueing and clamping. I went through the process six times, three for each side. So in terms of time spent... think "in excess of six days".

Glueing:

I used a waterproof wood glue to glue the gunwhales. This will work fine for this boat, as it will not be kept in the water permanently. Polyester resin does not have the same glue-like quality as epoxy so I couldn't glue the gunwhales with polyester resin. If I had been using epoxy the best choice would have been to glue the gunwhales with that.

On the inside of the boat I added a thick bead of thickened resin under the gunwhale. After the waterproof wood glue had set it was possible to strengthen the bond by adding this thickened resin that I shaped and smoothed with the wooden tongue depressor.

Clamping:

I didn't have enough clamps. Not by far. So I made simple PVC pipe clamps that I had read about online, and I made some wood & threaded rod clamps from scraps lying around. In the end it seems that the plans worked out as the gunwhales are glued very well.

Step 20: The Bottom Outside of the Hull

Picture of The Bottom Outside of the Hull

Pre-wet the plywood with resin, then added the pre-cut glass cloth and rolled on more resin. At this point I also started building up the bow and stern with glass cloth. I wanted many more layers of cloth on the two ends than anywhere else.

Step 21: The Bottom Inside of the Hull... Oh What a Tragedy

Picture of The Bottom Inside of the Hull... Oh What a Tragedy

This happened to be the biggest mistake in the whole build. I wanted to strengthen the floor of the canoe considerably by adding a thick chopped strand cloth/mat. This was done on a Sunday afternoon - meaning that nowhere in the immediate vicinity was a place where I could buy more resin...

So I precut the cloth, laid it in the boat, and proceeded to mix resin and work it into the cloth... at which point I realized that I did not have enough resin to fill the chopped strand mat...

I did my best, without trying to squeeze too much resin out of the areas that I could wet effectively. I was very angry at myself for making this mistake.

So the next day I set out to buy more resin and try to salvage what I could. Needless to say there were numerous problems, some of which you can see in these pictures.

Sanding... sanding.... sanding...

Step 22: Fitting the Bulkheads

Picture of Fitting the Bulkheads

This was fairly straightforward... I wet the deck support and sides with some clear resin, then placed the bulkheads in position and proceeded to cement them in place with thick beads of thickened resin spread along the joints.

Since the bulkheads were now in I could proceed to do the final layer of resin on the floor.

Step 23: Fitting the Seats

Picture of Fitting the Seats

Time came to glue the seats in place. They had to rest on the seat supports, with the added role of stiffening the boat.

Fixing the seats meant that I didn't need to add a yoke to the boat to keep the sides at a fixed distance. This was one of the advantage of fixed seating.

Thickened resin worked well to glue them in place.

Step 24: A Little Saving Grace

Picture of A Little Saving Grace

At this late stage of the game I found a solution for my (actual) blister-sanded fingers. The problem all along had been how to sand the curved seams in the boat efficiently.

This solution, using a dowel as curve guide, with some camping mattress sponge wrapped around it, became a much-loved tool. I could save my hand and finger muscles, while applying maximum sanding area to the glass. The piles of glass dust quickly built up using this method of sanding.

Step 25: The Black Stripe

Picture of The Black Stripe

I had wanted to add some colorful African design to the boat, but time was piling up and the summer holiday was approaching.

So I opted for a single thick black line running from bow to stern. The thickness of the line was determined by the lowest and highest line of the seam in the side of the hull. In the picture you can see the seam running inside the black stripe. The stripe was painted using an oil-based paint, painted directly onto the plywood.

Step 26: Glassing the Outside of the Hull

Picture of Glassing the Outside of the Hull

I had several meters of high quality, very fine cloth left from building model aeroplane composite gliders, so I opted to use that for the outside of the hull.

I glassed that, and was again reminded why I hated that specific cloth weight. Just have a look in the second photograph at the problems that came up...

More sanding.... sanding... sanding...

And even more sanding. I took the glass cloth right up to the gunwhale, but not over. I spent a half day each on sanding the underside of each outside gunwhale. A that point I managed to get really frustrated with all the sanding!

Step 27: More Glass for the Bottom

Picture of More Glass for the Bottom

In order to strengthen the bottom of the boat I added three layers of varying thickness, with two rectangular squares as extra patches in the area where we would stand.

I took special care to cover the bottom seam of the canoe with overlapping cloth since it would receive a lot of bumps during use. Higher up on the outside of the hull I settled for one layer of thin cloth.

While adding cloth to the bottom I always added extra glass to the stern and bow lines. In the end those areas have at least six overlapping layers of glass, sanded to conform to the hull shape and blended into the sides of the hull with a lot of sanding.

One of the best pieces of advice that I read during my research was that one shouldn't stand in the boat on dry land. I tried it and it is definitely an uncomfortable sensation hearing the wood and composite layers flex. On the water the 4mm plywood and 4 layers of cloth (3 outside, one inside) feel amazingly solid without making any noises or bending much.

I suspect that in the water the whole boat can respond to a weight bearing on it instead of a localized area when the boat is stressed on dry land.

Step 28: Adding a Thin Strip of Glass Tissue to the Top of the Gunwhales

Picture of Adding a Thin Strip of Glass Tissue to the Top of the Gunwhales

To protect the gunwhale from paddle strikes I added a one inch wide layer of glass tissue to the top flat area of the gunwhale. I stuck wax paper to the wet glass. When the resin cured I could easily pull the wax paper away from the glass. It did leave a fairly nice surface, but I didn't use the method on both gunwhales. It looked to me like the wax paper was prone to pulling fibres away making small bubbles.

The gunwhale done without the wax paper came out a bit nicer.

Step 29: The Final Varnish

Picture of The Final Varnish

I purchased 1 liter of marine varnish for the boat. And honestly, it is the best varnish that I have ever used. I love the smell of it, and I love the result.

The marine varnish sands really well, and adding successive coats is simple. I used sandpaper and a scotch pad to sand between coats.

When the boat hit the water the first time it had four coats of marine varnish. At some point I had to speed up the process since we were already in the summer holidays and watertight got preference over neatness.

However, I do plan to spend some time resanding the hull and getting rid of some drips under the gunwhales.

After varnishing the inside of the boat, the seats, bulkheads, decks and outside of the hull I still have about a twentieth of the 1 liter tin left. But I will buy another liter and add some more layers of varnish by the end of the summer.

Step 30: Testing in the Pool - and a Man and His Dog

Picture of Testing in the Pool - and a Man and His Dog

Time to get to the water... so the boat floated, and the carrying capacity is definitely in excess of 140kg's (308 pounds).

Getting in was really, really difficult the first time. It would have been easier to try this at a river or lakeside where my feet could be lower than the bottom of the boat. Getting in from the edge of the pool was nerve wracking.

As expected the canoe was really unstable (I am overweight and the seats are 14cm off the floor, remember) but we managed to sit in it while holding on to the edge of the pool. Later on I managed to stay upright for short periods of time.

The best result was me sitting in the boat with my feet hanging over the sides. Doing that allowed me to stay upright without tipping over.

This called for some action as it would have been unsafe to let my 4yr old daughter into the boat and onto a river with the boat as unstable as this.

I knew that I would get my balance back, since I used to surf ski/paddleski a LOT when I was in my late teens and early twenties. But I think the my overweightness is not good.

So I read up on outriggers.

And his dog...

I have no aspirations of being a swimsuit model, but I could not leave out the pictures of my dog, Roxy, finally enjoying her time in the canoe. From the first build pictures she was there. Any time that I got into the canoe she would also get in. Roxy doesn't swim and is scared of water. But she climbs into the canoe with great confidence and with no coaxing from me. What a dog!

Step 31: Building the Outrigger

Picture of Building the Outrigger

I looked around the garage for the biggest pieces of wood I had left. This determined the size of the outrigger. I would've made it bigger if I had longer pieces of wood.

As it stand the float is 110cm long, and 7cm high. The width is 10cm.

As for how long the outrigger poles (yeah I didn't reseach what the proper name for the "poles" is) should be... That was trial and error. I had a 2.4meter two by four piece of pine standing around. So I cut that in half, and the angle of the short joining pieces probably gave me an extra 15cm.

The rowing gap in between the side of the hull and the outrigger is approximately 60cm, which upon testing, proved to be sufficient.

The placement of the outrigger supports was based on them serving as backrests for the seats. Since the outrigger is 110cm long, I would assume that the distance between the two supports, when sitting in the boat, is about 1 meter.

Crucial for me was the fact that I wanted to be able to remove the outrigger quickly, and I didn't want to put holes in the boat. So I had to come up with some kind of clamping system.

To make the clamps I cut slots into the outrigger supports that would allow the galvanised screws from the clamps to slide back and forth. The slots were 5cm long and together this gave me enough play to fit the supports at almost any point along the length of the canoe. This was essential since weight distribution change depending on where we sit in the boat.

The clamps were made with round wooden wheels (they provide enough grip to fasten the clamp to the boat) with an 8mm diameter screw passing through the middle. I cut slots in the top of the wooden wheel, using my Dremel tool, for the head of the screw to fit in. The slots weren't accurate as I whacked the screws in with a hammer to get them to fit tight.

The bottom part of the clamp was simple a short piece of wood with an angled edge that would grip under the gunwhale. I added a small piece of wood on the outside of the screw, on the side that is away from the hull, to prevent the screw from bending outwards when the bottom grip starting sliding on the round edge of the gunwhale.

A nut is positioned on the bottom of the screw under the short piece of wood.

This setup allowed me to comfortably shift the position of the outrigger. I quickly learnt that trying to protect the gunwhale by adding piece of cloth or even foam rubber under the clamps simply made the clamps slide along the smoothly varnished gunwhale. So I ditched the idea of trying to protext the gunwhale. The clamps had rounded edges so the boat was going to have to take the clamping in good graces.

Step 32: Making a Paddle

Picture of Making a Paddle

I had a vision of the beautiful paddle that I would make to accompany my beautiful boat.

So while I was building the boat I spent time cutting and glue laminating the paddle blades and shaft. It was two be two one-bladed paddles - Indian style!

BUT...

By the time the summer holidays came round, and based on the stability issue, based on my family's receding patience with me sanding all the time, and based on the need for the whole thing to be water-ready, I redesigned the paddle to be a double bladed paddle, and I let go of the notion of crafting a beautiful laminated wooden paddle.

Shaping the blades:

To get it done I added a sanding pad to my electric drill and proceeded to power carve the blades into some kind of shape. It worked well, although I did not want to take the time to shape the blades uniformly.

I had thought that I could use a block plane to shape the blades, but the fact that I laminated a piece of hardwood to the end of the paddles screwed up that plan. The hardwood received the planing action cross-grain and would break out terribly. In future I won't glue a piece of wood cross-grain at the end of a paddle...

So the blades had to be shaped by sanding, as mentioned. I don't have a belt sander. That would have made life easier, I suspect.

Offsetting the angle of the blades:

In any case, I researched "feathering", or the angle by which the two blades are offset from each other. The best guideline I could fine was that the paddle could possibly be made to support the flow of your paddling stroke, with the aim of allowing your wrists to stay in a neutral position. So on it was to "air rowing".

I stuck the blades at the end of the paddle and settled for an angle that would be somewhere between 15 and 35 degrees offset from each other. This has since proven to have been a good decision. Supposedly the higher your paddling stroke, the more the blades will twist in the air, requiring a greater offset up to 45 degrees.

Covering/protecting the paddle:

I painted polyester resin onto the shaft and blades, reinforced one side of the blade join with fibreglass cloth, and covered the whole of the one side of each blade with cloth.

Result:

The end result is a fairly light paddle. It looks good, rows good and is extremely strong. The feathering between the blades is comfortable, and the length of the shaft allows me to get my hands close to the water without having to lean to either side for reach.

Step 33: Getting on the Water

Picture of Getting on the Water

I left my offroad vehicle somewhere where I can't find it, so I was stuck with transporting the canoe on the roof of my city car. :-)

I cut a "pool noodle" water toy in half, stuck it under the canoe, and strapped the canoe to the roof. It works, is stable and as long as I keep to the speed limit, within comfortable safety parameters.

PFD's

Personal Flotation Devices

My 4 yr old daughter got a small swimming vest that looks and functions like a life jacket. For myself, I will invest in a proper life jacket before we go out on any big waters. I doubt whether she will accompany me there since she can't sit still for that length of time.

Safety will always be my first concern. Sea currents, fast moving water, wave height (even on inland waters) and wind are things that all paddlers should be mindful off.

Tracking:

Our boat tracks well enough to enjoy the row. Without the outrigger tracking will of course improve. Turning radius is not small... Again, the outrigger plays a big role, but also the fact that the canoe bottom is flat. It doesn't turn up at either end.

Step 34: Final Words on the Build

Picture of Final Words on the Build

I'll do it again.

I'll use proper long sheets of cloth instead of shorter pieces bought at the hardware store.

I'll use polyester resin again. It costs less than epoxy and for a boat that doesn't live on the water, I'm happy with the long lasting qualities of the resin.

I don't like all the sanding. I'll sand less between layers of fiberglass. sanding is good and it improves the look of the craft, as well as the structural strength by allowing better adhesion between layers, so one can not avoid this. But I have a better understanding of when to sand and to what degree.

The outrigger is brilliant. It really makes the canoe usable and enjoyable instantly.

If you decide to or are thinking of building a stich & glue kayak/canoe/boat, go for it. It's very satisfying to see the end result.

My advice is to make a decision early on whether you want a showpiece or a functional watercraft. For a functional craft I could have left out the seats, holds, decks, bulkheads and extra fiberglass on the bottom. Then I would have had the boat in the water in half the time. But my need for holds and seats necessitated extra work.

Thanks for reading. Good luck with your own building efforts!

Stefan

Comments

boatmakertoo (author)2016-03-14

Great project. Designing one's own boat is very satisfying. The double chine is very elegant. The outrigger is also good idea. They work somewhat better if constructed as a hollow plywood float like a mini canoe with a lid. The buoyancy of the float stabilizes it in one direction and the weight stabilizes in the other. Properly sized the outrigger will allow you to sit on either gunwale. Canoes with outriggers and a leeboard can be sailed.

I have used both polyester and epoxy resin but hate the smell of poly. I use "Gorilla glue" for incidentals like gunwale molding. In the past there was a waterproof Weldwood powder glue that worked well. You added flotation chambers to the ends of the canoe, a very important feature. Plywood stitch and glue hulls are very light and will float when swamped but they have very little natural buoyancy. Bailing one out and getting back in is impossible without the buoyancy chambers. You should be able to get back in over the ends and bail the water out if you flip and swamp.

I too am over weight and would not consider a craft with less than about 2 square meters of bottom. Making a 4.6 meter canoe somewhat wider, say 90cm. in the middle keeps the draft shallow, is somewhat less tippy and can be rowed with oars from a center seat.

It is common practice to give canoes and other displacement craft a little "rocker" fore and aft. It is said that it makes the paddling easier. I don't know if that is true. It does complicate the design of the panels somewhat.

titchtheclown (author)2015-12-28

A few tips.

Cutting with a panel/hand saw or a japanese style pull saw makes saw lines wander less than with a jigsaw.

Don't wait for the glue to set between fileting (gluing the panels together) and putting on the reinforcing strips. Pressing the fibreglass tape into the wet seam means saving a lot of work sanding out lumps amd bumps and getting the waxy layer off the poly resin that enables it to set. Poly resin does not set in the presence of oxygen. Pros use poly without the wax in it for the first coats and then a top coat that had wax in it to avoid the work of cleaning between coats but you need to go to specialist suppliers to get it.

Epoxy is more betterer but poly is ok. If you shop around epoxy in bulk can be cheaper than poly from a hardware store. I got 6 litres of epoxy for about the cost of four 500ml tins of poly from my local hardware store. Epoxy can also be stored for ages without problems while poly will set in the tin if stored for too long.

StefanV13 (author)titchtheclown2015-12-29

Hey Titch

Thanks for the tips and info and taking the time to comment.. I found a lot of interesting new ideas in what you said - certainly some stuff that I will Google up on.

The Japanese saws are something that I really wan to investigate. I've seen a lot of it in Youtube videos. Then, of course, I looked around and saw Cape Town South Africa around me. I have looked in hardware stores but have NEVER seen any of those saws.

titchtheclown (author)StefanV132015-12-29

Very few of the hardware stores here in Australia have real japanese pull saws but some carry the American copy http://www.irwin.com/tools/handsaws/double-edge-sa...

Our daytime tv used to be plagued by an infomercial for one brand.

Using a european style standard carpenter's panel saw is trickier but cutting using a very shallow saw angle will help cut down on tearout. There are also specialty finer toothed verneer saws designed for cutting verneered panels and plywoods.

GeorgeP70 (author)titchtheclown2016-01-22

The best way and the easiest way to make a scarf joint is to clamp the side pieces together mark the overlap on both pieces then draw the diagonal line on both the top and bottom, and cut on a band saw

MoP1 (author)2016-01-18

Great 'ible! I just had to comment, so I could gush about how cute that pic of you and your little girl is! It's so cute, it hurts... :)

farna (author)2016-01-06

On several boat building pages a simple butt joint is recommended for joining lengths of plywood in light craft such as this. A scarf joint is a bit stronger, but a close butt joint with 6" of fiberglass tape on each side is just as strong or stronger. The polyester resin common in auto body work (auto parts stores) works fine, but the stronger epoxy or vinyl ester is generally stronger. I've used polyester for building a 14' pirogue (sp?) -- a flat bottom canoe -- with butt joints on the side. Left out in the weather with nothing but a coat of laytex paint to protect it, the polyester seams (a single layer of tape on seams, no reinforcement inside) will crack over the winter. I stored it upside down outside, and it got a lot of sun too. Other resins are more weather resistant, or use a high quality resin, not the cheap auto parts store stuff. Here's a good US source of info and products:

http://www.fibreglast.com/product/the-fundamentals-of-fiberglass/Learning_Center

1MoClimb (author)farna2016-01-16

Wrong, do the scarf joint if you want a quality built boat. Takes more time but it's well worth it. Since a proper boat it covered in glass cloth inside and out, you do get the additional strength that 'sandwich' provides. Also, my kayak was quite torsionally flexible until I added the deck and bulkheads. If you build a narrow canoe you might as well make it a kayak by adding front and back deck covers.

rippa700 (author)2015-12-28

Lovely job! I made a similar one 6 years ago and the UV has finally wrecked it, but it provided loads of fun. Best part is attaching the gunwales - sudden strength and rigidity to what seems to be a floppy mess. The only thing I did different was the original butt joint of the 2 sheets of ply. I planed a matching taper on both peices (I think 12 times the thickness of the ply for the length of taper) and epoxy'd that together. Makes a continuous sheet and very strong. Yours looks better finished than mine! Well done.

StefanV13 (author)rippa7002015-12-28

Hey rippa. Thanks for the comment. So 6 years hey? Sorry to hear about that. I'm hoping to go longer than that by keeping it hoisted against the roof in the garage, out of the sun.

Your idea of scarfing (I think that's right?) the angle and joining the sheets that way is a good one. I can imagine that it would be strong enough, AND MAKE FOR SIMPLER SANDING!! I spent quite a few hours sanding and glassing that jointing panel. I'll keep that in mind for future projects. Thanks!

1MoClimb (author)StefanV132016-01-16

Built an 18' stitch and glue kayak from Chesapeake Bay some 15 + years ago and it still looks like new. Used good mahagoni plywood, marine epoxy and expensive clear varnish. These boats should really last forever. Re-varnish from time to time after sanding and they will look like new - mine does.

hartqwerty (author)StefanV132016-01-12

Epoxy and poly aren't UV stable. If you want it to last it needs a coat of paint. My paint of choice is Rustoleum Topside Paint, I also know someone who re-fiberglassed an old touring kayak and painted it with regular house paint. That was 12 years ago and the kayak is still in great shape.

Waalcko (author)2016-01-10

Great instructable, very well documented. I enjoyed reading it.

farna (author)2016-01-06

In my last comment I meant that a scarf joint in combination with fiberglass tape on each side is a bit stronger than a butt joint with fiberglass tape. Can't edit comments once posted!

T-ke (author)2015-12-28

I was thinking.
the first step of joining the 2 4 mm sheets together.
would it be possible to put them under a router.
let's say make one side on both of them 2 mm thick over a 10 cm area
and glue them together on this overlap?

maintann (author)T-ke 2016-01-05

unfortunately doing this will give you two weak points with only 2mm of ply & a weak 2mm thick butt joint. Better by far to scarfe or butt block your joint.

8:1 scarfe on 4mm ply is not hard but practice is needed to make a good one. Sit the two sheets on top of each other with the top one flipped over. Lay the top one so it is 32mm ( 4 x 8) back from the bottom one. Draw a line across the top one a further 32mm in. Set the sheets up so they JUST overhang the edge of the bench & clamp firmly. Use a sharp plane working diagonally down across the sheets until you hit the line on the top sheet & the end of the bottom one. Glue up with a good epoxy being careful to line up properly & apply light clamping pressure (use polythene sheet to prevent sticking to the bench.

StefanV13 (author)T-ke 2015-12-28

Hi T-ke. Yeah. I can imagine that will work well. I'm assuming you saw Rippa's comment on creating an angle scarf joint? Similar idea.

Perhaps that scarf joint will be easier to position and get the two sheets flush because it can slide up and down... The outer layer of plywood is so thin that to sand it down till any inconsistency is flush often means sanding through the outer layer and hitting visible cross-grain.

Having said that... this is a exploratory self build and if your skills with a router is supreme then your idea will definitely work. Adding that as a build option might give someone else the courage to proceed. There is no risk of the boat collapsing around the joint since the joint is strengthened by the 180 degree flow of the wood from one side to the other. The half-pipe shape adds a lot of rigidity to the joint. Plus, of course, the composite laminate of the glass.

Either way, if I understand you correctly doing the joint that way would eliminate the need for that glued piece of wood? As Rippa said, it make a continuous piece of wood that looks nicer and I'm guessing makes the sanding a lot more straightforward.

Send pics if you manage it!

OmarJ3 (author)2016-01-05

Your length to beam ratio appears to be about 4.6 to 1. You might have made it 4 to 1 for better stability. unless you are looking more to an Olympic type shell. As it is, you could build a second hull and make a sailing catamaran.

I MP (author)2016-01-05

I have built several stitch and glue kayaks so have some tips. Do not use butt joints to join lengths, scarfe them8 to 1 for an overlap which you glue. When lofting I like to use a light chain the make the curve since that is easier than a long lathe. I use 4mm Okume mahogony plywood but any 4mm will work, In the US you can use 3/16th plywood underlayment which is water resistant on one side. I cover all surgaces with epoxy to create a composite. I tend to use marine paint as a finish however any good 20 year house paint will work. I use paint since I am building kayaks and do not want to look like a log if overturned and upside down in the water. When stitching I use fine wire which I can cut and remove after taping the inside of a seam. I love my Japanese pull saws for working with thin plywood.

My next project will be a fabric skin on frame kayak.

ossum (author)2015-12-28

Great Instructable, I enjoyed the read, this is something I have considered doing for a while. What software did you use to determine those lofted shapes?

I don't see myself building a full-size one any time soon, but I imagine the technique could be very handy for building RC boats too.

Also, great to see a fellow South African on Instructables. Contests are open to SA now too, so you should enter this when an appropriate one comes up, perhaps the "Brave the Elements" one that is on right now would be a good fit.

StefanV13 (author)ossum2015-12-28

Hi Ossum. Yeah! Cape Town rules. Good luck with the heat for the rest of the week.

With regards to the loft shapes... Unfortunately I don't have a very brilliant solution. I figured out that the touching sides of the panels should be the same length, and that the length of the further edge determines the "roundness" or "bulge". So I built models for each generation of drawings. So sadly I can't offer a better solution.

I use Blender 3D for my design stuff. I've always wondered how boats are made so that the water doesn't run back up the drive shaft from the prop. I can't think that a seal on a moving shaft can be that watertight?

ossum (author)StefanV132015-12-28

Hehe, yeah, it's weather for watersports now, that's for sure.

Your drawing method makes a lot of sense, especially for a relatively simple hull like a canoe. I just finished a double-hull RC airboat with all kinds of nightmare lofted surfaces/curves, modelling it in SolidWorks was an exercise in patience/frustration. I intend to post an Instructable on it soon. I have never quite gotten my head around Blender.

The only solution i could figure to the water-up-the-tube problem was to have the motor above the waterline inside the boat, so water runs up the tube that contains the prop shaft to some degree, but not into the boat. I don't know if that's how its usually done though.

Ghostrider13 (author)ossum2016-01-05

Water going up the tube is handled by a couple of seals that prevent that but water on a homemade still can get in. A lot of boats have a small drain plug that allows water to be sucked out while the boat is moving. If the boat stops, then water goes backward into the boat unless it's a oneway valve. A small sump pump can be rigged up and connected to a small battery like the type used for lawn tractor / motorcycles. Besure to trickle charge them if you get it. Keeps the battery from going bad.

titchtheclown (author)ossum2015-12-29

A program i have used is http://carlsondesign.com/software/add-ons/sharewar...

It is purpose built for boats and even generates dxf files to run cnc cutters or routers, not that many of us have access to one of those, let alone one big enough for a whole sheet of plywood.

ossum (author)titchtheclown2015-12-29

Thanks titch, I am going to try that out, it looks really interesting.

AlvacirF (author)2015-12-28

Good job ! Congratulations.

StefanV13 (author)AlvacirF2015-12-29

Thank you!

BrianEV (author)2015-12-29

A lot of good work there, and very helpful to post both what worked AND what didn't. Thanks!

I built a cedar strip/fibreglass canoe many years ago, following a design meant for river travel. It had no keel but had more of a rounded bottom than you managed. Even so, I found adding a small keel (about 3 cm wide x 1 cm deep) made tracking and stability better. If I were to build a canoe like yours, I would split the bottom down the centreline and give it perhaps a 20 degree rise from the centreline on each side. Might also add that keel, for stability and to avoid wear problems.

StefanV13 (author)BrianEV2015-12-29

Hi Brian

Thanks for the comment, and kudo's for completing a strip canoe!

I think your suggestion for a keel is a good one. I considered splitting the bottom of my canoe towards the end, and pushing a 4 mm. piece of ply into the slit to force it to bend outwards. Maybe on the next one!

T-ke (author)2015-12-26

brilliant build.
a canoe is one of the things that are an my ' things I like to build ' list.
very nice instructible you made.
do you have an idea of the total price of the build?
and is there a way to get the plans?
not so good with computer things...

StefanV13 (author)T-ke 2015-12-26

Hi there. Thanks for the comment. I'm guessing the build cost at around $200. Definitely under $250. I can post the panel measurements for sure. They are the same as in the computer drawing image, but I can give better instructions? No need to get into computer designa for this. Just measurements put onto the plywood sheets based on the drawings.

T-ke (author)StefanV132015-12-26

I had a second look at the computer drawing,
I see now that all measurements are on there, sorry.
so the drawing is repeated 4 times correct?
I will definitely have a go on this canoe.
given the fact that over here you pay €450 for a pump it up canoe, an at least €600 for the cheapest polyester or plastic models.
( there isn't much demand here for one so choice is limited)

would be a verry nice project to do with my nephew.
and much cheaper for the few times a year I can use it over here.

thanks allot for the info

StefanV13 (author)T-ke 2015-12-26

Hi. Yes. the measurements are on there, but feel free to ask. I've added a better quality measurements pic, and a diagram showing that yes, quite correctly, the plans need to be measured out four times.

Good luck on the build when you embark on it. A big variation on this build would be to leave out the seats and add cross-beams or "thwarts" across the top. It means the occupants can sit on the floor, or add removable seats. I liked the idea of seats, and the idea of thwarts wasn't cool. But now, with the outrigger attached, I guess the score evened out.

I should point out that the outrigger is a "must" in terms of the enjoyment factor. From what I read almost everyone comments that their canoes disappoint in their expectations due to the "unstableness". Any kind of outrigger, even a closed off pvc pipe one, will add a LOT of stability.

T-ke (author)StefanV132015-12-28

thanks for the clearer dimension plans!

Hough_Creations (author)2015-12-27

Very impressive

Thank you!

ronopotomus (author)2015-12-27

This is a great project. I'm going to try this with my Scouts. Thanks!

StefanV13 (author)ronopotomus2015-12-27

A pleasure. Thanks for the comment.

I was thinking about what would be cool about this build for a scout troop... and my conclusion is that it would be an amazing maths/dimensions exercise to mark out the measurements of the canoe panels on the plywood, and then to see those flat surfaces bend themselves into curves.

Having a troop available might make lighter work of sanding, so that's a positive!

Also, the experience of working with a composite building technique such as wood encased in fiberglass and resin might spark some future design ideas. Composites are the way of the future and this is a subtle and simple introduction.

Good luck if you decide to go ahead and please don't hesitate to ask or share thoughts!

BernieSR (author)2015-12-27

Thats a fantastic project . Your descitin of the trial and trubulaitons are very helpful

StefanV13 (author)BernieSR2015-12-27

Much appreciated comment. Thanks.

phuckoff (author)2015-12-26

How Awesome!

StefanV13 (author)phuckoff2015-12-27

Thanks!

Just4Fun Media (author)2015-12-27

That canoe looks beautiful! How long did the total process take?

Have a great day! :-)

StefanV13 (author)Just4Fun Media2015-12-27

Thanks for the compliment. The whole process took about 4 months of evening work and four or five weekend days. Would've been quicker if I just wanted a quick canoe. But the seats and holds added time... and the allure of that gleaming varnished finish sometimes seduces one to sand that little bit extra. But only sometimes...

geller6980 (author)2015-12-27

very cool

it was like reading a story

StefanV13 (author)geller69802015-12-27

Thank you. Appreciate that.

jhawkins14 (author)2015-12-26

Coming up on my lost of things to build too. Thanks for the Instructable. Beautiful work.

StefanV13 (author)jhawkins142015-12-26

Thank you

ClenseYourPallet (author)2015-12-26

Great work... The canoe turned out great but my question is about your garage door. Holy cow is that beautiful. Is there any story behind it

Hah! Thanks. No story unfortunately. Standard old meranti-wood type garage door. Big and heavy!

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