Introduction: Cedar Strip Kayak
While a wood kayak may seem fragile, strip built kayaks are actually incredibly strong and lightweight. With this construction method, it is not too difficult to build a boat that outperforms anything you can buy at a store. By building your own boat, you are in full control of everything from the seat pads to the design of the wood strips.
I finished this kayak two years ago, and have paddled it a lot since then. It performs very well in the water, and is fast and maneuverable.
The finished weight is 35-40 lb, which is 15 pounds lighter than a comparable plastic kayak. The light weight of a wooden kayak makes it incredibly easy to transport on land and maneuver on the water. The total cost was somewhere between $500 and $600, and took about 6 months to build.
Step 1: Planning
This build seems like a daunting task, but after reading and rereading this book it becomes a lot more doable. I built the 17' Petrel sea kayak by Nick Schade, and this book describes in good detail exactly how to build it and two other boats. I would highly recommend getting a book on whatever design that you choose to build.
Strip kayaks are built on forms, which are basically a perfectly straight wooden beam with cross sections of the kayak spaced out evenly down the length.
Within this book is what's called a table of offsets, basically a list of numbers, and from that you can lay out the cross sections of the kayak. I did it this way but it did take a long time. If I were to build another kayak I would spend money on a set of plans to save time.
Step 2: Strongback
The strongback is a straight piece of lumber that the forms are screwed on to. This part is not too hard but is probably the most important part to get get right in the build. Any twist in the beam will translate into a twist in the kayak.
I built my own strongback by laminating two pieces of carefully selected, tight grain softwood together, and then laminating another piece one top of that (shown in picture). This is better than using a 2 x 4 because it is less likely to warp and twist as the moisture content in the wood changes. This beam was built to the length specified in the book by Nick Schade, and I made sure it was straight by stringing a chalk line down the center.
Step 3: Making the Forms
I created the paper forms using the table of offsets mentioned earlier, but these can be purchased as plans from a place like Chesapeake Light Craft. I spray glued the paper forms onto 1/2 inch MDF board and then cut them out with a jig saw.
The forms have a line for whats called a "sheer strip", this is the divider between the deck and the hull and is important to get exactly right. Another important step here is cutting out a hole for the strong back, as seem in the picture.
The strongback runs through the center of the forms and you need to cut a rectangular hole for it to pass through. The location of the strongback is different for each form and is shown on the plans.
There are two more forms that are specially made to fit to the shape of the bow and stern, they are shown in the picture and are screwed to the ends of the strongback.
Step 4: Aligning the Forms
Since the forms are what determines the shape of the final kayak, they need to be exactly correct before building is started. If the forms are in the right position, you can do a bad job of stripping the kayak and fiberglassing and it will still be a functioning boat with the correct proportions. The strip-built method of building a kayak is forgiving for this reason, but the forms still need to be accurate.
To begin, I marked the location of each form on the strongback and then slid them onto the strongback. you can hot glue the forms onto the strongback temporarily so they don't move around. I drew a line down the center to determine if it was straight and temporarily clamped some strips to it to see if it was a smooth curve.
I had to slightly adjust the shape of the forms with a rasp and adjust the position of the holes to get the right fit. Once I was sure it was right I hot glued the forms onto the strongback with wooden blocks, and then screwed them on (shown in photo).
Step 5: Selecting Wood and Milling Strips
I used western red cedar for my kayak with black walnut accent stripes. Cedar is the most commonly used wood because it is lightweight and easy to work with. One problem I came across was that the walnut strips were so hard that they wouldn't sand as easily as the cedar around them. This could cause raised spots on the boat where the harder wood is.
I got 1 inch thick cedar lumber at Menards, and I sorted through all the wood to find the pieces without knots. The dimensions of the strips for this kayak are 3/4" x 1/4". Since the wood I bought is 1" thick, I ran it through a planer to exactly 3/4" thickness, and then cut strips at 1/4" wide. The thickness of the board will now be the width of the strips.
I made a jig (first photo) to accurately cut strips at 1/4" every time, on the left side of the saw blade. This jig saved a lot of time and made cutting strips safer. The dimensions of the strips need to be constant so you don't have to sand off too much later.
After they are ripped on the table saw, I ran the strips through a router jig with a bead and cove bit (image four). The bead and cove allow the strips to fit together at any angle and save ton of time. The bead and cove must be exactly centered on the strip and go right to the edge of it. I made the bead first because the cove is easily broken.
The feather boards on the router are so the material fed into it can only move forwards.
Step 6: Laminating the Bow Strips
The bow and stern strips are pieces of wood that are on the inside of the boat, and the strips are glued to them.
To make these, I cut a bunch of cedar strips that are thin enough to make the bend around the form (1/16" thickness or less). The width is shown on the plans and I laminated enough of these strips to get the right width.
I dry fit them to make sure it looks good, then glued the strips together and taped it to the forms (you need a lot of force) (no photo of that). After it dries, you can use a plane to get it to the right shape. I then used masking tape to tape it to the form temporarily (shown in photo).
Step 7: Attach the Sheer Strip
The sheer strip is the divider between the deck and the hull, and it is probably the most important strip because it determines where every other strip will go. The plans show the location of the sheer strip on each form.
To start stripping, we will flip the kayak for to the hull side first, because the hull is easier and its good to get practice before stripping the more visible deck.
The edge of the strip the meets the deck must be beveled with a hand plane so that the deck matches up with the hull well. This bevel is not constant throughout the length, which makes it difficult. I clamped pieces of wood at the correct angle (in photo), and matched the bevel to that angle for every form.
Once you get it beveled, staple the strip to every form making sure it makes a nice curve down the length with no bumps. Glue it to the laminated bow and stern piece we made earlier.
Step 8: Stripping the Bow and Stern
Now the confusing stuff is over for a while! The stripping of the hull and deck needs no precise measurement, but the strips to need to fit together well.
Before stripping the kayak, remember that the kayak needs to be removed from the forms at some point. To make this easier, I put blue masking tape on the forms so the strips won't stick to the forms. I used staples to attach the strips to the forms, and if you're worried about staple holes looking bad, it doesn't look that noticeable. I decided to not use staples on the top of the deck, but it took a lot longer that way. The staple holes will be filled with epoxy when you fiberglass, so that have no effect on the final boat.
After the sheer strip, I put the next strip on more or less horizontally, with little curve down the length (the upper strip in photo one). I stapled this down and then filled in the space between this strip and the sheer strip (smaller strips in photo one).
To fit these smaller strips in place, first cut the strip to a little over the final length. Then, hold it up to where it will be and mark the angle that needs to be cut for it to fit in. The way I did it was I cut the angle with a block plane, do a trial fit, and then readjust the angle if necessary. Once you have the angle cut, make a rounded bead on it with the plane so it fits into the cove on the next strip.
Once the strip fits well, glue it to the adjacent strip with regular wood glue. Waterproof glue is unnecessary because water should never penetrate the fiberglass layer.
Step 9: Stripping the Hull
After these fill-in strips, I took long strips and went up the side of the hull, stapling them down then gluing the ends of strips together (since my strips are shorter than the 17' kayak). Sometimes you will need some tape or something to force the strips into position if the staples aren't enough, especially around tight bends.
Step 10: Accent Strips on Hull
I added an accent stripe of walnut as shown in the photos for decoration. Once you get up to the oval-shaped bottom of the hull, you need to start beveling again with the hand plane. For me fitting strips and working with the hand planes was a very fun part of the build.
The last strip on the hull is a challenge because it involves a lot of beveling, but it isn't too bad.
Step 11: Scrape and Sand the Hull
The hull is now stripped and it's starting to look like a boat!
I removed all the staples with a pliers, and then scraped the rough edges with a scraper I got from Chesapeake Light Craft (really great tool). After scraping it, I sanded with a heavy grit sandpaper with a random orbital sander.
Important!! Always be moving the sander, and never put too much pressure in one position or dig the edge in to get it to sand faster. You also need to change sandpaper frequently so it cuts well. This is so important because you need the boat to be a smooth curve, and not wavy.
Step 12: Stripping the Deck
Now that the hull is done, you can flip the kayak over and start on the deck.
The first step is to make another sheer strip, and bevel it to match the first strip on the hull. This will not be glued to the hull! The deck and hull will be two separate halves until later.
You can do whatever you want for a stripping pattern, what I have here is just one possibility. I included walnut accent strips on a sharp corner on the deck to go along with other stripes on the hull and side.
The deck is done the same way as with the hull, and you now have experience with beveling strips. With the Petrel kayak I built, there was a tight turn that the strips had to make near the cockpit. This was a very difficult area to build, and staples were not enough to hold the strips down.
I went without staples on the deck, and I used a mini strip to hold down each strip (photo five and six). I stapled the mini strip to the forms, and that held each strip in place as the glue dried. With this method you have to wait until the glue dries to put on a new strip, so it takes longer. If I were to do it again I would use staples on the entire kayak.
Step 13: Laminate the Bow and Stern
After I finished the deck I laminated a piece to fit on the outside of the bow and stern. This is done in the same way as before, only it is on the outside this time. I chose to use walnut here for looks and because it is a hard wood, but cedar would be fine (and easier to sand).
I cut thin strips of the walnut, than glued each strip to the next one. Working quickly while the glue was wet, I used strapping tape and put as much force as I could on it to get it to bend around the curve. After it dries you can shape it with a hand plane or saw rasp (awesome tool).
Step 14: Cut Out Cockpit Opening
With the plans there should be a paper shape for the cockpit opening. Lay this out on the deck, mark the opening, and carefully cut it out.
I glued a thin strip of walnut around the edge for decoration and to make the opening smoother. I found that tape is the best way to clamp it down.
Step 15: Build the Cockpit Recess
To built the cockpit opening, I cut cedar strips to fit onto the opening made in the last step. I glued these together with CA and accelerator. I would highly recommend this glue because it sets immediately when you spray the accelerator on it. Once you have the strips glued on, cut out the opening for the cockpit (on the plans).
This would normally be a terrible joint, but thankfully the fiberglass and epoxy will give it plenty of strength. You can trust that this will be strong once it is fiberglassed.
Note: I did this differently than what was called for in Nick Schade's book
Step 16: Scrape and Sand the Deck
Once the deck and cockpit opening is complete, scrape and sand it just like the hull.
Step 17: Fill Gaps and Sand
After sanding, go over the deck and the hull and fill any gaps with a wood filler of a matching color.
Once that dries, sand some more with 80 grit or lower, using a light at a low angle to see the smallest of imperfections. Remember to hold the sander flat and keep changing the paper so you end up with a smooth boat.
Step 18: Wet the Wood and Sand Again
After sanding, I wet the wood so it swells and fills up small dents. This is the first part where I got to see what the kayak will look like when it's done, and it starts to look great when the wood is wet!
After it dries, go over it with a finer grit paper again, I used 120 grit.
Step 19: Fiberglass the Hull
Fiberglass seems really hard, but it really isn't too bad and is actually fun to do! Before you start however, remember that its important to wear gloves and a respirator with an organic filter when working with epoxy. Some people develop sensitivities after getting in contact with it.
Fiberglass is very simple in principle, all that's needed is to wet the glass with epoxy until it is fully transparent, then scrape off the remaining epoxy. You need to remove the excess so that the glass cloth sticks to the wood and doesn't float on a layer of epoxy. Epoxy is very dense, so any excess will also increase the weight of the boat.
Fiberglass is what gives the kayak its strength, and it needs too be applied to the inside and the outside of the boat. I decided to use one layer of 6 oz glass on the exterior and interior hull, and 4 oz glass on the exterior and interior deck. I ordered fiberglass cloth and slow drying epoxy from US Composites, and would order from them again.
To begin, roll out the glass onto the exterior of the hull. making sure not to stretch the weave. cut the cloth roughly to shape, leaving a bit of excess material. Carefully brush the cloth until it fits over the hull smoothly without and wrinkles (image three). Cut a dart in the fabric at the bow and stern (image four). Then, working quickly and precisely, mix a cup of slow drying epoxy at the correct ratio and dump it in a strip down the middle of the hull. Quickly squeegee the epoxy around to wet out the cloth. You will start to see it become transparent. You want to see the weave of the cloth, and if you can't there is excess epoxy.
Mix more epoxy and repeat until the hull is finished.
Go over the entire hull with the squeegee and scrape off excess epoxy using downward strokes (you should see the weave, but it should be transparent).
Step 20: Fill Coat Hull
Once that coat is dry, add a coat of epoxy to fill in the weave of the glass. This is best done not too long after the epoxy dries, so it chemically bonds to the previous layer. Apply this with a brush and get a nice even coat, working from one end to the other.
Step 21: Fiberglass the Deck
Apply the cloth and fiberglass the exterior of the deck in the same manner as with the hull.
Step 22: Fill Coat Deck
Apply a fill coat to the exterior of the deck as with the hull.
Step 23: Scrape and Sand the Interior
Now that the exterior fiberglass is in place, the boat is strong enough for scraping and sanding the interior. This doesn't have to be perfect as you won't see much of the inside, but it does have to be smooth enough to get a good bond with the glass.
I modified my scraper to a rounded edge so that it works for concave surfaces, scraped the rough spots, then used a sander.
Step 24: Fiberglass the Interior
This part was difficult because fiberglass cloth does not like to conform to a concave surface. The interior is done in the same manner as before, only it is harder to get a flat layout.
After it the cloth was laid out, I added a filler of epoxy and microballoons (US Composites sells it) to the bow and stern of the hull (white stuff in photo three).
I did not add a fill coat to the interior because it is unnecessary weight added to the boat. The bumpy finish of the glass weave helps with traction when getting into the boat as well.
Step 25: Sand the Exterior
The fill coat allows us to sand out any irregularities without cutting into the glass. Carefully sand the entire exterior (not the inside) with heavy grain paper, changing it often and applying even pressure. Do not cut into the glass, as it will weaken it. You know you're cutting into the glass when you can start to see a white weave.
You will likely need to apply another fill coat to the entire boat, then sand again. After sanding, you may need to give it another fill coat and sand if it is still an irregular finish.
The fill coats and sanding are what give the kayak a smooth curve, as they fill in any low spots. The trick here is that you have to apply the fill coat to the entire boat, not just the low spots.Then once it dries, sand the entire boat evenly.
Step 26: Build the Cockpit Coaming
After sanding, I built the vertical portion of the cockpit coaming using alternating walnut and cedar strips. This proved to be a challenge later because the cedar would sand a lot easier then the walnut, leaving low spots.
I glued these using the same method as before, and made the sticks longer than they needed to be (make them extra long in both directions, it will be cut flush later). After gluing the sticks, I taped around where I want to cut the fiberglass, and fiberglassed the entire cockpit coaming with 6 oz glass.
After it dried, I cut the cloth at the tape line and peeled off the tape, leaving a clean line. Now, add a fill coat and sand just like the rest of the boat.
Step 27: Laminate and Fiberglass the Cockpit
Now that the vertical sticks are in, we can laminate the lip of the coaming. I did this in the same way as the bow and stern earlier, with thin strips. I glued them and used a bunch of clamps to bend it around the cockpit. I used wood blocks to ensure a constant height.
After it dries, cut the vertical sticks flush with a hand saw, and rasp and sand it so its all smooth (saw rasp is great). I cut a little piece of walnut for the front where the strips couldn't make the bend.
Fiberglass and epoxy the cockpit, then fill coat and sand like before.
Step 28: Cut Holes for the Hatches
After that, we need to cut huge holes in the kayak! This is scary, but if you measure it carefully it'll be fine. The measurements for the hatches are shown in the plans. I marked the outline, then used a fine toothed saw to cut along it very carefully.
Important! The wood you cut out here will be used the the hatch, so don't cut into it at all. It's important to cut within the line.
Step 29: Make the Hatch Lips
Now that the hatches are cut out, make a lip for them to rest on. The way I did it was to cut wide strips of cedar, then glue them around the hole. The hatch will rest on this lip. I sanded the edges round and epoxied it in place. I used masking tape again to remove the glass easily.
Step 30: Drill Holes for Deck Lines
Deck lines are great for when you're out kayaking and I use them all the time. You can do whatever setup you want with the deck lines, but I like to have one in front and one behind me.
Once you have it measured where they will be, you will need to drill holes where they are mounted. If there is any exposed wood, it will rot, so to get around that I drilled the hole oversize, filled it with epoxy, then drilled a smaller hole in the epoxy. Now the water can't get into the wood.
Later on, we will mount bolts here to install the deck lines.
I also used this method to install a carrying handle and paddle holder later on.
Step 31: Attach the Deck and Hull
Up until now the kayak has been in two pieces, but now we need to join them into one. I had to adjust the bevel of the sheer strips, but if you get it right earlier you won't need to. I also added a walnut accent strip where the halves meet.
Once you get the halves lined up well, hold them together and tape the sides together with strapping tape. This tape is reinforced so you can put a lot of pressure on it. Really crank on the tape so the joint is nice and tight. At this point there is NO glue in the joint, it is a dry fit. Now, once the entire boat is taped up and the halves are fit together, we will take a length of fiberglass tape, coat it in epoxy, lay the kayak on its side, and lay it out on the inside seam on the boat.
To do this, you need to affix the fiberglass tape (covered in epoxy) onto a stick, and jam it into the end of the boat. Then, with a brush screwed to a stick, brush the tape down flat onto the joint. The epoxy will wick into the seam. Repeat this for the other side on the inside, then tape the outside seam (in photo).
Step 32: Fill the Bow and Stern
Now that the kayak is together, we need to fill the inside of the bow and stern. Lift the kayak vertically (maybe in a tree), then mix some epoxy with microballoons and dump it down into the bow and stern. Don't pour in too much because large quantities of epoxy can heat up and smoke!
Step 33: Lots of Sanding
After all of that, we need to get the boat ready for varnishing. The varnish is necessary because it protects the epoxy from UV light. We need to sand the entire boat evenly from course to fine grit paper.
You may need to add another fill coat or two to the entire boat, and sand again to remove low spots.
Step 34: Varnish, Sand, Varnish
After it was thoroughly sanded, I made a dust free tent in the garage and applied six coats of glossy, UV protecting marine varnish to the boat. I sanded with 400 grit in between coats.
To save time, I would varnish the hull first, the hang the kayak by the carrying holes in the tips so the deck was upright. this allowed me to coat the hull and the deck at the same time, doubling the efficiency.
Step 35: Fit Deck Lines, Hatches, Foot Pegs, Seat
After the varnish is complete, the boat is glossy and looks great! The only step remaining is to fit it to the paddler. I ordered deck lines, aluminum foot pegs, a seat back, and foam from Chesapeake Light Craft. I installed them as per their instructions, and added wooded carrying handles. The seat was made from a block of foam. I installed flush hatches as per this tutorial: https://www.clcboats.com/shoptips/fitting_out/hatches_no_toggles.html. There are lots more tutorials on that website, and they help a lot.
Step 36: Paddle!
This kayak has been amazing to paddle! I've had it on the water a lot and have put it to the test. It is easy to roll, fast, light, and maneuverable. It can get a little cramped in the cockpit, but that snug fit is important for rolling or braces. The light weight of this boat makes it easy to carry with one person as well.
I hope this Instructable helped, and good luck to anyone who decides to build one!
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Outdoor Fitness Challenge