Let’s Make a Boat Part 1/2 – Supplies and the skeleton of a boat

by Learning Lead – Paul Whipp

Finally the time has come. The time we have all been waiting for. It’s time to start building my boat! I am splitting the build into two blog posts. In this first blog post (1/2), I am going to share how I gathered and prepared supplies and built my sailing canoe frame. 

But first, before we get any further, I should let you know that I made a lotta mistakes building my boat. Learn from my mistakes… and make some of your own. I think someone once told me you learn the most from your mistakes. If that’s the case,I have been learning a ton! When (not if, number of boats required = n +1) I build my next boat I will be better prepared. Keep persevering and stay positive.
I let you know in my last blog post that I bought the plans for my sailing canoe. If you missed it, I got the plans from Gentry custom boats. I would recommend anyone making a skin on frame boat for the first time buy plans. Most plans will include a tools and materials list, step by step instructions and other helpful resources. I mostly followed the plans, only making minor modifications.

Let’s jump right into the build. The big steps in my build process were:

–sourcing and prepping materials*

-building the frame*

-skinning the boat

-finishing touches and add ons

-sewing things (sails, skirt) 

*covered in this blog

Sourcing and prepping materials:

The main parts for the boat are the:

-frames and stems 

-keel, gunnels, chines and carlins

-polyester skin

-hardware and sailing additions

Frames and Stems

My build plans came with printable templates for the frames and stems. I only changed one thing about the frames. I made them slightly taller in the middle so the deck would have a slight crown. This will hopefully mean any water that gets on deck is more likely to slide off back into the water than come into the cockpit. After I printed the templates to the right size and made my slight modifications, I traced them onto 12mm marine plywood. I then cut the frames and stems out with a jigsaw. The frames make up the cross pieces of the wooden skeleton and give the boat it’s width and depth. The chines and keel (long pieces) will slot in along the perimeter of the frame pieces. There is a stem at the bow (front) and stern (back). These stems give the bow and stern that nice canoe curve. 

When cutting the frame and stem pieces, my advice is to go slow and be precise. Especially where other pieces need to fit into slots and such. Make sure to cut the slots big enough or you’ll have to cut them bigger or sand them later.

Keel, gunnels, chines and carlins

The keel is a plank that runs lengthwise along the middle bottom of the boat. The gunnels are the top outsides that run lengthwise. The things you shouldn’t hold onto in a canoe if you’re tipping but always do. The chines are like the gunnels but go on the sides and bottom of the boat lengthwise. There are two carlins and they run along the outside of the cockpit (where you sit in the boat) and help make up the top side decks. For my boat they all had to be 16ft long (except the carlins at 7ft) but various widths and thicknesses. I cut them using a table saw, apparently called ripping when you cut lengthwise. They are Western Red cedar. The original planks I bought were 12ft long and 4 inches wide and 1 and 7/8 inch thick. I had to buy a few because they weren’t 16ft. To make them long enough I scarfed them. This means cutting two matching angled ends and joining them. I made a simple jig to cut the angles and went with what most people recommend which is a 1/9 slope (the pictures help make sense of this if you’re confused).

Then I epoxied these matching pieces together to make a 16ft pieces. A staple helped to keep the pieces from slipping. With epoxy, clamps don’t have to be tight. Apparently if they’re too tight all the epoxy is squeezed out. Not good for bonding!

**Important note!!! When you scarf, you lose length in your pieces because they overlap. Don’t do a bunch of math without taking this into consideration. All your hard math work will become useless.**

After glueing the keel, it had to be soaked and pre-curved to help give the boat shape. To soak the keel I made a long narrow trough and filled it with water. I made the trough with a large tarp, the help of our back fence, some bricks and broken drumsticks. I soaked the keel for two days. I used more bricks to weigh it down and keep it under water. After it soaked, I placed it between two lawn chairs and hung some old oil jugs in the middle to bend it. I left it like this for about five days.

Polyester skin

The polyester skin is from the states (George Dyson). I think it’s industrial filter fabric. I’ve read that he buys in bulk and then sells to skin on frame boat makers because apparently big filters won’t sell small quantities to individual boat makers. The material is untreated and uncoated polyester. I had to get 9oz for the deck and 10 oz for the hull to avoid sewing pieces together.

Hardware and Sailing Additions

Epoxy and stainless steel screws keep the boat from falling apart (hopefully). I got six10 west systems epoxy that fits in a caulking gun, pretty niftee. The screws were from my local hardware store (I made many visits to the hardware store, never got enough screws). 

Sailing rigging and hardware are from various sources. Basically whoever had what I needed for the best price. Duckworks in the US had lots of good stuff (sail making materials, rudder parts, cleats, etc). A few Canadian sites had good deals on rope and other small things too (Chandellery and Binnacle). If you’ve got a local place that’s great because shipping will get you.

Building the Frame

In order to start assembling the frame, I needed to make a strongback. This is what the frame is built on until it is complete and straight (hopefully). My strongback was made of a two by four about 11 feet long. A small plywood rectangle was screwed to each end to attach the first and last frame. The strongback was also screwed to two sawhorses. All this I set up in my living room.  Not ideal but better than the -10c and snowy we were still getting outside.

Now the fun begins! To start assembling the frame I clamped the first frame to the front of the strongback and the last to the back. I made sure these were level, at the right height and centered with the strongback and each other. 

Next, I layed the bottom gunnels (the gunnels were two pieces glued on top of each other) into the coinciding top most notches in the first and last frames and used tie down straps to keep them from falling out. I measured the positions of the other frame pieces and began spreading the gunnels and placing them. I needed a couple extra straps here and there. Many a frame fell to the floor during this process! But all of a sudden, it looked like a boat. Or at least the skeleton of a boat. It was important at this stage to measure and make sure each side of each frame was at an equal distance on the gunnels. If they are skewed, this can lead to twist which is when the frame slants to one side or the other.

The next order of business was screwing and glueing. Each frame is screwed and epoxied to the gunnels. Holes are countersunk and pre drilled so that the screw heads don’t poke out and so that the wood doesn’t split. Epoxy usually takes at least 24 hours to cure at room temperature. I’m not using a lot of epoxy but it’s still important to have good ventilation and wear proper protection. Always follow the manufacturer’s recommended precautions. 

The front stem was then attached by screwing and glueing it to the first frame and the gunnels. Again, making sure it is straight and level takes some patience. The ends of the gunnels get cut at an angle so they sit flush on the stems. I screwed them using a single screw through both and the stem. 

It’s time fo chines! These slot in similarly to the gunnels. They fit into the notches in the frames and I temporarily held them in place with straps.

Once they were all slotted in and I double checked everything was level and not twisted, I glued and screwed. Same process as the gunnels. Predrill and countersink and then add epoxy and put the screw in. This whole process was pretty time consuming for me and probably took a full three days. Keeping things level and straight was a constant battle but very important. 

Still lots to do topside. The top of the gunnels were then glued and screwed to the bottom gunnels. I used gentle clamping pressure here and there. The carlins were then placed into their appropriate notches on the top inside the gunnels and glued and screwed.

The kingplank, mizzen plank and side decks had to be measured and cut next. The kingplank is basically the foredeck. It’s two pieces of 6mm marine plywood and looks kinda like an arrowhead on my boat. I layed the full sheet of plywood on the front of the boat and traced under the inside of the gunnels to get the shape. Where the kingplank curves in I used a thin and flexible scrap piece of wood to trace the curve. Measure this curve so the kingplank doesn’t end up horrendously asymmetrical, as mine did round one. The kingplank also slots around the front stem. To get a more accurate tracing, I used a cereal box and traced on this and then transferred to the plywood.

The kingplank is again glued and screwed. Do the bottom piece and then the top gets glued to the bottom. The mizzen plank was way easier. It was just a rectangle of 12mm marine plywood. Glue and screw.

The side decks are single layer 6mm marine plywood. I did the same as the kingplank and layed the sheet on top of the side deck and traced the shape underneath. A couple of extra pieces of western Red cedar are glued to the inside of the gunnels to help support the side decks (which get sat on in sporty conditions). 

I made the kingplank and side decks rise up to the front of the cockpit, again to help any water on my deck find its way back to whence it came. Raising the kingplank up also meant there would be more footroom if I were to ever sleep aboard. I also reinforced this area just in front of the cockpit with 12mm plywood because I planned on installing stabilizers (you’ll see in the photos to come).

All these plywood pieces are being cut with a jigsaw by the way. I find the jigsaw takes great concentration to keep on track and as I get distracted quite easily some of my cuts were less than perfect. Oh well, if they were too wide, sandpaper was a quick remedy. Too shy, no such luck. With all these pieces glued and screwed all that’s left on top is the back stem and the very small rear deck. The back stem is fitted based on height above the ground and hanging angle. Again, the gunnels and chines are cut at an angle and fitted flush and then glued and screwed. The back deck is a piece of 12mm plywood and I used a cereal box a second time (thank god I love cheerios) to get the shape right. Glue and screw (do I even have to say it).

Finally, once everything has cured, the top of the frame is done, for now!

Time to flip this sucker over. Once flipped, the keelson and keel are installed. The keelson is the same as the keel except 6mm plywood and not western Red cedar like the keel. The keelson goes down first with some epoxy where it hits the frames and stems, then some epoxy, then the keel and then pre-drill, countersink and screw it all in place.

Don’t get too excited cause we’re not quite done with the frame yet. The sailing bits come next. Mast partners are cut in the kingplank and mizzen plank. Best to cut these after you make the masts but they are the holes the masts go into. Drill holes in the corners of a traced square and cut with a jigsaw. My boat has two sails, main (front) and mizzen (back). So I needed to cut two partners. But I also wanted to be able to sail with just one sail so I did some rough calculations and cut a third mast partner closer to the cockpit. The mast bases also need to be installed. These are layered squares of 12mm plywood glued to the bottom of the boat under the partners where the mast feet slot into. Glue and screw to the keel. Don’t forget to cut a channel in the bottom piece to let water out.

The other important sailing bit is the leeboard bracket. The leeboard is like a keel or dagger board on most sailboats except it swings up and down on the side of the boat instead of in the middle. The bracket is extra reinforcement and is a 12mm plywood “L” bracing against the gunnels and chines and the middle frame. Glue and screw. At a lot of these high stress areas you can (should) put extra epoxy in the form of a fillet. A long bead that is slightly flattened or left rounded. 

I almost forgot, we also need to sit on something. The floor of my boat is 6mm plywood about 14 inches wide and long enough to stretch the full length of the cockpit plus some at the front. I want to be able to sleep in the boat in a pinch so I made it just long enough for me to fit on. Under the floor are spaced cleats that support the floor evenly. 

Ok, now the frame is done. I think. No, ya it’s done.

Sand and coat with marine spar varnish to your heart’s desire. So purdy!

Next up, skinning a boat, making the sailing bits and bops, finishing touches and sewing the sails.