Intro: Making Petrel Play - a Strip-built Wood Kayak
This is video series is documenting my process of converting the idea of a new kayak into a physical vessel and taking it out on to the water. I will be building my “Petrel Play” design. I hope you will find this series inspirational and maybe even decide to build your own small boat.
The boatbuilding technique shown in these videos is called “strip-building.” This process involves take narrow, thin strips of wood, bending them around a form and gluing them together. Once the forms are completely covered with the wood strips the surface is smoothed and then covered with fiberglass cloth. This cloth is adhered to the wood with epoxy resin. This makes the wood shell strong enough to be removed from the forms. The interior is then smoothed and further reinforced with more fiberglass.
Various parts are added while the deck and hull are separate. The boat is then reassembled and after further sanding is ready for finish.
This makes it all sound very simple, and in a sense it is. The process is a sequence of accessible steps that anyone with the desire to take on the project can reasonably expect to perform successfully. Building a kayak using this technique can be done by a beginning boat builder without any experience in woodworking.
That said, it does take some patience. As you will see while watching the following videos, there are a lot of individual steps. This is not instant boatbuilding. This is a project you choose because the project itself is appealing to you.
Before we dive into the actual process of making the Petrel Play kayak, I would like to introduce you to the design and give you some background into how I came up with the design of the Petrel Play and what it is designed to do.
The Petrel Play is a 14-foot-long by 23-inch-wide kayak suitable for easy paddling on a small lake or bay but it is also a lot of fun out on the open ocean in big waves and surf.
I first started thinking about this design around 2004. At that time, I was developing my original Petrel design. I was waffling between a long, narrow traditional sea kayak, and a shorter, wider touring or cross over design. A short, wide kayak tends to be more maneuverable and easier to handle, but long and narrow will usually be faster.
Any boat design is based on a series of choices and balancing various compromises. As I worked on the Petrel design I sketched up long designs and played around with shorter designs. I ended up settling on a 17-foot-long by 20-inch-wide design that served my needs of traversing long distances efficiently while still be responsive for playing in tide races and surfing on storm waves.
Creating a new kayak is a process of iterating on earlier ideas. While working on Petrel design I took off from my Night Heron design which incorporates Greenland Inuit kayak influences, these are combined with modern sailboat ideas, and concepts borrowed from other contemporary kayak designers.
The Petrel includes a transitioning chine. The “chine” is the area on the hull where the side becomes the bottom. This can be a sharp or hard angle, or a rounded or soft curve. On the Petrel the chine starts out rounded at the front and becomes hard behind the cockpit. The hard chine in back creates a control surface for surfing while keeping bow looser so it is less likely to lock-in on waves.
The overall hull shape has fullness out into the ends giving it a high effective waterline length for good efficiency and it also bolsters the stability of an otherwise narrow kayak.
The Petrel is one of my favorite boats, but when I wanted to adapt it to stitch and glue construction, I thought I should also revisit my desire for a shorter, wider version.
While longer boats are capable of moving faster through the water, at the speeds most people typically paddle there is very little efficiency benefit in going longer than about 14 feet.
Any longer than that requires the paddler be quite strong to gain an advantage and even then the benefit will primarily occur only if you are pushing the kayak hard. Moving at a comfortable cruising speed, a shorter design will often be easier to paddle due to less wetted surface area and having less boat sticking out in front and behind can just be easier to handle.
Stitch and glue is another technique for building small boats and has the advantage of being quicker than strip building. By building with accurately cut plywood panels I would be able to build a 14-foot-long version of the Petrel at the same time I built a 17-foot version.
Making a design shorter has consequences. It reduces the volume so the kayak will not carry as heavy a load. Making it wider and a bit taller recovers much of the lost volume. In adapting the longer Petrel to create the Petrel Play I added some width, made the cockpit a bit deeper and I also reduced the amount of overhang. Going with a more plumb bow and stern shape allowed me to maximize the waterline length, giving as much speed potential as possible.
The stitch and glue method is very well suited to creating hard chined designs it requires a little bit of finesse to simulate the transitional chine toward the front. The addition of an extra panel allows for a pretty good approximation.
I am really pleased with the stitch and glue version of the Petrel Play (or Petrel Play SG). It is plenty fast enough to keep pace with 18’ sea kayaks and is very quick and responsive playing in tide races.
The short length makes it easier for my wife to handle and the added width provides a bit of additional stability making it very comfortable in conditions.
While I really like the Petrel Play SG, I personally like strip-built designs better. I think they look better and the narrow strips offer more design freedom than the plywood panels. I really wanted to get back to the strip-planked idea I had years ago.
I was finally able to fit the project into my schedule last year primarily by finding a customer who wanted me to make him a strip-built Petrel Play.
Let’s take a look at exactly what this design has going for it:
Again, the design is 14 feet long, and with the plumb bow and stern, the waterline length is just about full length. The boat is fast, in sea trials my friends and I were able to sprint the Petrel Play SG up to 8, nearly 9 miles per hour (That’s over 7 knots or around 13 kilometers per hour). Obviously, this is a sprint and can’t be sustained for long, but the design cruises along nicely at 4 mph.
At 23 inches wide with a fair amount of flare, the design is quite stable with good initial and secondary stability. The flare continues up to the bow providing reserve buoyancy.
Like the Petrel, the Petrel Play has the transitional chine that hardens up behind the cockpit. I took a lot of inspiration from the old Mariner “Coaster” designed by the Broze brothers. With a slight lean, leaning into the side flare, you can turn the boat very quickly.
The cockpit is recessed at the back to stay out of the way when leaning back which allows for easier rolling for those who wish to learn. The flat area on either side of the front of the coaming provides a comfortable place to brace your thighs, and knee braces can be incorporated if you want extra support.
The cockpit shape provides plenty of room for your legs. The feature line or chine extending forward is placed to maximize room where you need it without creating an overly high deck that would catch the wind.
Below the feature line the deck slopes away creating a narrow catch area for your paddle so you don’t have reach out too far to the side allowing for a relaxed, comfortable and efficient paddling posture.
That feature line continues forward to where your feet are, providing plenty of room for paddling booties.
A high bow cuts cleanly through waves and then drops down to minimize windage creating a graceful profile.
My customer wanted a retractable skeg. While not strictly necessary, it provides a nice additional dimension of control. With the skeg deployed the Petrel Play tracks nice and straight, retracted it is lively and maneuverable.
The finished weight of the boat is about 31 pounds (~14kg). This light weight translates into a spritely and responsive kayak that is easy to carry to the launch. Despite its lightweight I have found strip built boats to be very durable and tough. I don’t baby my personal kayaks and they absorb a lot of abuse.
I am very pleased with this design and think a lot of other people will enjoy it as well. If you want to do relaxed paddling in sheltered conditions, the lightweight, 14-foot length and comfortable stability will be a lot of fun. Personally, I like going out in rough, active waters and I can say the Petrel Play is a hoot.
In the next video in this series I will start milling the wood to make the kayak, I’ll cut out the building forms and set them up. I hope to release a new video every week or so, but if you want to be kept up to date on the progress, please subscribe to my YouTube channel via the link provided. Also, if you are interested in building Petrel Play or another kayak yourself, follow the link to my website where you will find plans and instruction books.
Thanks for your interest, I hope you enjoy this series, and happy paddling.
Step 1: Cutting Forms
To build a wooden kayak you first need some wood. I went to Liberty Cedar in Rhode Island and picked through their stacks.
I got variety of material for different projects, but the best color was in some 2-by Western Red Cedar. I find I get the best results when my strips have vertical grain. This is easiest when you have flat grained boards of the right thickness. You just rip strips off the edge. But, good quality 2-by material is usually vertical grained. So, to get vertical grained strips, I first rip blanks that are ?” thick then turn these on their side and rip my 3/16” thick strip off the blanks.
I try to keep the strips in sequence. This way if I choose to match the strips, I can do so. I bundle each original blank into an ordered set. Then keep the sets in order. The first milling operation is cutting the blanks. I use a power stock feeder on my table saw for safety and a consistent cut.
Note that I’m wearing a dust mask. Cedar dust is seriously evil. I have an industrial dust collector pulling dust from the saw, but some still gets in the air. I also wear hearing protection. With the saw and collector going the noise level is dangerous.
I like to check the consistency of my cut with calipers. If there is a problem I can run the blanks through a thickness plane. Once the blanks are cut and consistent they are turned on their side and the strips are cut.
This MagSwitch feather board is great for controlling the ever-narrowing blanks. Just unlock and slide it in. The stock feed does a good job, but the long boards are easily shifted. The feather board keeps everything running straight and true.
I use an inexpensive Freud Diablo 7 ?” Framing saw blade with 24 teeth. They have a very thin kerf to minimize the material lost to saw dust. After each blank is cut, I bundle the sets together in sequence. On this boat I ended up choosing not to match the strips. So I actually shuffled the pieces and swapped about half of them end-for-end to avoid any unintended patterns.
I print my plans out full size on paper. Each form is drawn by itself, with space around it. My expectation is people will take these paper plans, cut out the form patterns and glue them to a piece of MDF, or plywood or whatever material they may have that is suitable for making temporary forms. These can then be cutout with a jigsaw or band saw… …and trued up with a stationary sander.
But, I’m not going to do that. I have a CNC Machine. Holes cut into the stations keep the weight of the finished form set down, so the strongback is easier to move.
If either milling the strips or cutting the forms seems beyond your capability, Chesapeake Light Craft can provide either, or a complete kit with all the needed material. The spine of the forms is a strongback. This is a rigid reference to hold all the form stations. I’m using an extruded aluminum tube, but you can make a box beam out of wood. The goal is something straight and true to hold the forms securely and accurately in place.
The forms are strung onto the strongback in order. I placed a couple spacer blocks inside the hollow extrusion to center the end form on the strongback. A couple screws shot through the strongback into the endforms secures them in place so they won’t slide off the end. The spacing between stations is 1 foot or 30 cm. This is the distance between reference faces.
Since the kayak tapers towards each end, a strip running down the length will only touch the square edge of the form at one point. This is the reference face. At the front of the boat, the reference face is the forward face of the form and as the boat tapers towards the stern, the rearward face is the reference.
The gap between most of the half inch thick form is 11 and half inches, except in the middle where the reference face change from front to back. Here the spacing is just 11 inches. I make 11 and half inches long spacers that fit between the forms and wrap around the strongback. One spacer per form at each end of the kayak. I cut one of the spacers to accept a couple wedges for between the middle forms where the spacing is 11 inches.
The pressure from the wedges secures all the forms, but they may need some adjustment. Checking the alignment of the reference lines on the forms, I find some are slightly rotated around the strongback. A few of the forms near the ends were not clamped by the wedges. These get a spot of hot melt glue.
I don’t want to glue the strips to the forms, so I’m wrapping the edges with packing tape.
Step 2: Installing the First Strips
The inner stem fills in the sharp triangle on the inside at the bow and stern of the kayak. While this does provide some strength, for our purposes it just provides a convenient landing place for the strips at each end of the boat.
While I was cutting out the forms I made patterns for the inner stems. I traced these on to one side of a piece of 1/2 inch thick pine. I used the band saw to cut along the outer edge, then traced the same pattern on the other side.
A centerline marks the sharp edge of the bevel.
I want to create the bevel between this centerline and the inner edge of the stem. I find it hard to see what I'm doing on this the light colored pine.
So, a series of pencil strokes provides a quick guide to where I'm at.
The bevel should be a flat face from center to edge with no crowning between.
I don't try to curve the plane cut down the length of the stem. Instead I create the curve from a series of straight cuts.
Once I've got the bevel to my liking I re-trace the inner edge of the stem from my pattern.
I then cut the stem off the half inch blank along that inner edge line.
A quick touch on the sander cleans up the saw cut.
The bevel of the inner stem needs to be continued on to the end form matching the angle of the sectional forms.
A sharp plane cuts the MDF pretty well, but you can also use a rasp or coarse sandpaper.
When the bevel is done it should be a continuation of the inner stem shape.
Since I don't want the stem forms to be part of the finished kayak, I cover the bevel with tape.
The inner stem is part of the finished kayak. I'll eventually glue strips to the stems, but for now I'll hold them in place with masking tape.
With the stems in place, it is now time to start fitting strips. The first strip usually follows the sheer line, or the widest part of the form. When I made the forms I marked the sheer with notches.
I place little clamping jigs next to the notches to hold the first strip while I determined the length.
The jigs support the strip in position so I can accurately measure it.
With the strip aligned at one end I lop it off at the other end.
The ends of the Petrel Play curve up sharply. Full width strips usually have trouble bending enough. Since, narrower strips will bend easier, I taper the ends. I think it also looks nice.
Since each stroke of the plane takes off a little bit, where ever you plane more, more will be removed. So, by stepping back a bit with each plane stroke, you will end up creating a taper.
By planing the sheer strips for both sides of the boat at the same time, I end up with two identically tapered strips.
The sheer strip needs a bevel to mate with the deck. If you leave the edge of the strip square, you will end up with a large gap. With a bevel on each sheer strip they will match up with a tight seam.
I created bevel guides by clamping sticks to the forms to bisect the angle between deck and hull.
The bevel changes from form to form, or what is called a rolling bevel. I start by putting the tapered strip back up on the forms.
I write the form number where the strip crosses each form. This helps me keep track of my location on the strip as I create the rolling bevel.
The gap between the strip and the guide sticks is what I need to eliminate.
When I place my plane on the strip I match the gap I just saw at the guide stick. If I maintain that same angle as I plane away the corner of the strip I should eliminate the gap.
I continue planing until I think I'm nearly there, then I check to see how I'm doing.
Once again, I check the gap
And match the gap
Then I check at the next form, working my way along the strip.
In between the forms, I roll my wrist while planing, to transition from one bevel to the next.
When the bevel looks good, its time to secure the strips on place.
A simple staple is a quick clamp.
I align the strips to the sheer mark and double check that it runs fair and true.
When I have both sheer strips installed I glue the ends to the inner stems. A small amount of glue, a clamp and wipe off the excess.
The sheer strips are on, now we can start making progress.
Step 3: Stripping the Sides
Some people may have noticed that I am not using cove and bead strips. When you are working on curved sections the cove and bead creates a quick tight joint between strips. I'm using square edged strips which will open up wide gaps on curved sections.
But if I bevel the edges of the strips, I can get tighter seams than when I use cove and bead.
In the previous episode, I installed the sheer strip on forms. I beveled the bottom edge where it will mate with the deck, but the top edge is still square.
If I add more strips directly on top of the prior one, I will get gaps between each.
I could bevel the new strip, but instead I use a plane to bevel the existing strip. By holding the plane flat against the forms I make the top edge of the strip square to the form above, so the new strip fits squarely on top.
I made a tool to hold a small rabbet plane. The rabbet plane cuts right up next to the form. The tool holds the plane flat against the form and helps the plane stay on the strip edge.
I run the plane along the edge until it cuts across the full width of the strip. At this point the top edge will be square to the form above it, allowing the next strip to fit tightly.
I'm sorry I don't have better video of this process right now. I'll show it in more detail in later episodes.
I don't bend the second strip to follow the sheer. The sweep of the sheer requires a lot of difficult bending and I think it looks better to let the strip run straight. I follow the sheer for awhile, then just let the strip run naturally to the stems.
I'll fill the space remaining at the ends with cheater strips later.
Before applying any glue, I check to make sure the fit between the strips is tight.
I only need glue where the two strips will be touching.
The squeeze bottle contains yellow carpenters glue. The small outlet hole on the bottle keeps the bead of glue small.
The next strip is pressed firmly into the glue and temporarily held in place with a spring clamp and a little notched jig.
I push down on the strip while I shoot staples in at each form. For now, I only staple where there is glue.
At the ends, I eyeball the second strip to make sure it runs in a fair curve then mark its landing spot on the inner stem.
A little glue and a clamp holds it in place.
After I glue and clamp the other end, I secure the strip with staples where it separates from the sheer. Then I use masking tape to tighten up the seam between the strips.
The ends of the strips are cut just proud of the inner stems.
At this point it is a matter of just adding more strips for a while. After 10 or 15 minutes the glue has tacked up enough that I can remove the tape. I then dry fit the strip to check how much beveling is needed, use my beveling tool to square the edge for the new strip, check that the fit is good, add glue, staple and tape the strip.
I kept on adding strips until I had gone a bit past the chine.
At the chine the angle of the strips changes suddenly. Since the chine is not parallel to edge of the strips I need to cut them back a bit and then bevel the new edge.
The forms have a couple guide lines to help. There is a long diagonal that is on all the forms, and a short bevel guide that is only on the forms where the chine is most pronounced.
I want to transfer these lines to the outside of the strips. I use a little jig with a notch cut in it to reach around the strips. Note that the two marks actually align to the same point.
I make a pencil mark where the jig hits the outside. When I trim back to this mark while following the angle of the bevel guide I create an edge ready to accept the next strip.
Since the diagonal line is consistent on all the forms, I lay my transfer jig along it. I make a mark at each form.
I can then connect these dots using a spare piece of strip. First I align the edge of the strip to the mark, then clamp it in place. I double check that it creates a fair curve down the length and then I mark the line with a pencil.
Using a Japanese saw, I cut down the length of the kayak, cutting just outside the line.
I clean up the bevel using my rabbet plane. I either square up the edge or match the bevel mark.
With the long strips up the sides complete, I'm now ready to install cheater strips in the remaining gaps at the end.
The first step is cutting a strip roughly the length of top of the gap.
I then mark the length of the taper.
This first strip narrows down to almost nothing before it ends. To roughly mark this I clamp a scrap piece parallel to the end, then bend it down to the mark.
This makes a smooth curve to guide my cutting.
The quickest way to remove the excess is a few swipes with a sharp pocket knife.
Now it is a matter of planing off all the material that prevents a tight fit. I get close to the line and then do some test fits. I plane off the spots where the strip binds up first.
With a good fit, the strip will slide into place without displacing the strip below.
A little glue on the inner stem, the newly tapered edge, and the top edge of the strip.
A few pieces of tape to squeeze the seam tight.
With progressively shorter tapers with each successive strip the tapering and fitting get easier as I go.
The ends of the cheater strips are trimmed off just proud of the inner stem after they are all installed.
Step 4: Stripping the Hull Bottom
Unfortunately, during the time I was stripping one half of the bottom of the boat, I had the GoPro pointed at the floor. So here is some time lapse of the floor. Just at the top of the frame you can see me diligently adding strips to one side of the bottom. It may be hard to make out, but I am just adding one strip after the other, being sure the strip is long enough that it overhangs the centerline at either end.
I stop when I have the whole side extending slightly beyond the centerline.
Like I did for the chine in Episode 4, I use my marking jig to transfer the centerline from the forms to the outside of the strips.
I then lay a strip down along these marks. I clamp the spline on the waste side so when I go to mark it with a pencil, the clamps aren't in the way.
The spline is never straight initially, but by getting my eyeball down near the line, I can see the problem areas. Usually just loosening the clamp and letting the spline relax will straighten it right out.
I use a sharp pencil because fat lines are hard to follow.
I'm cutting as close to the line as I can without touching it.
A side-rabbet plane works well to true up the centerline. I'm using a Stanley #79. I keep checking the edge. First to make it straight, then I concentrate on getting it on center.
Pare down the high spots, with longer and longer strokes.
When the centerline is straight and true, the real work of strip-building starts. I now need to fit the other side up against this straight edge.
You need start somewhere. I'm just making an eyeball guess a some kind of a bevel.
I try to lift the strip up in its installed orientation. The plane is held to match the flat surface the strip will fit against. This should be good approximation to start with.
Test fit and see where it touches. Visualize how the strip end meets the surface. And reproduce that with your plane.
Maintain that same orientation as you shave away the end of the strip.
I'm seeing a little gap between the strips where I need to adjust the bevel.
The strip twists from nearly flat to almost vertical in the space of a couple forms. A heat gun melts the lignin in the wood making it softer and more pliable.
As the wood gets hot, you will feel it relax slightly and accept the twist. The strip will stay twisted when it cools off so it will be easier to hold in place on the forms.
Once I have the end fitting well, I clamp the strip in place and dry-fit it all the way to the other end.
I mark across this new strip onto the existing strip to indicate where it should line up when the far end is installed. Now I can release the strip to work on it more easily.
By backing off a bit from this mark I give myself room for error as I work on fitting this end.
Again, by maintaining the relative orientation of the strip I'm working on, to the space it needs to fit, holding my plane to match that fitting surface will give a good first estimate at a tight fit.
From there I look to see where the strip hits and shave away that spot first.
When the bevel looks good it is time to refer to the marks made earlier and trim back the length.
If the marks line up at this end, I know it will fit at the other end.
At this part of the kayak the strips have a lot of twist. The heat gun trick helps pre-fit the wood so it is not such a strain to hold it in place.
It doesn't take a lot of glue to make a strong kayak. We only need enough to hold it together until the epoxy and fiberglass are applied.
If I did everything right, aligning the length marks will assure a tight fit at both ends.
Once I have stripped past the knuckle of the stem I have some more solid reference points to guide the fitting process. I can mark where the new strip hits the keel line by sliding it to the point where it touches.
After sliding it back out to the right length I transfer that mark to the new strip and draw a taper from the mark to the end.
I just hack the excess off with a jack knife. It is handy, quick and efficient.
Once again, I resort to holding the strip in its orientation while hold the plane to match the vertical surface of the keel line. I don't need dead perfect on the first try.
I'll test fit before I've planed down to my pencil line. That line is just a reference, what matters is how it actually fits.
I inspect the taper and the bevel. If pointy toe hits first I know to concentrate first on that end, if there is a gap at the top I will adjust for that.
I hold the appearance of the fit in my mind as I place my plane against the wood. By reproducing that fit, but replacing the plane for the keel line I will shave away until the fit with the plane is tight. This should mean the fit with the keel line would also be tight.
There is still a fair amount of twist here, so the strip gets the heat treatment to pre-shape it.
When this end is all set, I dry fit it in place, and then mark the length at the other end.
Even though you have seen it a few times now, lets slowly go over this process of fitting strips again.
Mark the length of the taper.
Draw the taper guide line.
Whittle off the excess.
Plane the taper smooth.
Adjust the bevel if needed.
Here the toe or point is tight, but the heel is a bit loose. See how it is low compared to the other side.
So I shave back the toe just a little bit.
The heel or wide end of the taper is only down slightly. That is close enough.
I temporarily clamp this end in place.
And dry-fit the strip down the length to the other end.
Make a mark to indicate how the strip will fit.
Then remove the clamps so the it is easier to handle.
Mark the taper.
Note that the length marks are offset a bit to give me extra length to work with.
Just hack off most of the scrap.
Match the orientation of the pieces while you are planing.
Check your fit.
When the fit is good, work on the length.
Note the space between the marks.
The length is now perfect.
I can now glue and staple.
When I get to the point where I have space for less than 2 strips, I glue a couple strips together. These will form my closing strip.
I align one edge of this strip with the straight edge of the keel line, then reaching in from below I mark along opposite curved edge with a pencil.
The pencil didn't fit all the way into the pointed ends of the space so I continue the lines using a straight edge.
This is one case where it is often easier to head over to the band saw to trim off the excess, but I can't be bothered to walk that far.
I proceed with the fitting one end at a time. First I want to get the pointed end to the correct taper.
Notice that I am testing the fit with pencil marks up, instead of on the bottom where I originally traced them. This is intentional. It means that the straight edge of the strip I'm fitting will lay against the curved side of the space it is fitting into.
In other words all the strips on either side of the center line are bent in towards the keel and these closing strips will continue that pattern.
I work on the taper starting at the point and shaving my way back towards the widest section, gradually fitting it down as I proceed.
A pencil mark along the hull surface indicates how much needs to be shaved off.
When one end fits really nicely, I start working on the other. Like before, some pencil marks help indicate how much length is needed.
Like the first end, I start at tip, making sure it fits well before working down the length.
The fine taper may produce a flag end that doesn't plane off easily. I have a solution.
Like before, I first work on getting the taper tight, then shave back the taper to adjust the length so it fits from end to end.
With a good fit, its ready for glue.
Masking tape makes an excellent clamp
Step 5: Stripping the Deck
Back in step 2 I planed a bevel along the edge of the first strip I installed on the hull. The goal was to eventually create a miter between the hull and deck for a smooth tight seam.
Now that I'm working on the deck, it is time to create the matching first strip for it.
As I did on the hull, I write the form number where the strip crosses each form. This is just a quick guide to keep track of where I am working.
I start the bevel by looking at how wide a gap I have. I then hold my plane so I see a similarly sized gap.
Holding that angle constant, I keep planing until the gap disappears.
I then check my work, and if it looks good I move my way down to the next form, slowly rolling the angle of the plane as needed.
The strip twists sharply from almost flat at the bow to nearly vertical at form 4. Heating the strip softens the wood allowing me to lock in the proper twist before the strip is installed on the forms.
With both sheer strips fitted and twisted on each side, I need to join then together.
By overlapping the strips I can roughly estimate the centerline location. It should be where the inner edges cross. The strips are not long enough for the outer edges to cross, so I do my best to eye-ball it.
There is always a convenient scrap to use as a straight edge. I mark the taper. Its just a first guess, I don't need it to be perfect.
I'll plane down towards the line. I hold the face of my plane vertical to simulate the angle of the face where the two sheer strips will meet.
With both sides roughed out, I check the fit. The toes touch. This means I need remove material from the pointy end first.
When I get a nice fit, I can staple the strips down. Notice I am not gluing these decks strips to the hull strips. If I used glue here, I would be hard pressed to remove the forms later.
I do want the deck strip glued to each other.
I repeat the same fitting process at the stern of the kayak.
The next set of strips follow the centerline.
I align a pair of strips with the centerline and mark where their outer edges cross the sheer strips.
I draw a taper from that mark to the end of the strip.
The most efficient way to get down to the line is to whack off most of the excess with a pocket knife and then I use a block plane to ease in on the line.
When I check the fit, I'm looking at both the taper and the bevel angle.
I'll hold my plane to match the gaps I see and plane until the gaps are gone.
Since both sides need to fit simultaneously, I work on both sides before finalizing either side.
There is a slight crown to the deck along the centerline, so the edges between the strips need a little bevel.
I can then work on finalizing the fit at the ends.
When the fit looks good enough, I can apply glue between the strips, add glue at the ends and then secure the strips in place with staples.
A little tape binds the junction between the four strips nice and tight.
These center strips only extend to the cockpit area of the deck, so I'll repeat the same process with some new strips at the other end of the kayak.
So, I started with strips following the sheer and then added strips down the centerline. I'll continue with this pattern, sheer followed by center, for a while. It matches well with the curved sides.
This pattern continues until the side strips intersect the feature line feeding into the cockpit area. From there on I'll just run parallel to the centerline.
Since I'm using square edged strips instead of cove and bead, I am not guaranteed a tight seam between them.
My Robo-Bevel tool forms a bevel on the top edge of the strip that is square to the form above it.
The shoulder plane takes a very fine cut. While this takes longer, it limits tear-out and helps prevent plugging up the throat with chips.
The strips following the sheer line continue past the feature line and are then trimmed back using the marks on the forms as a reference.
No need to have the staples in the way.
Connect the dots with a scrap strip.
I'm cutting just outside the line, but I want the feature line to end at a strip intersection, so I stop the cut without going into the last strip.
Now the sawn edge needs to be cleaned up using a rabbet plane.
I'll keep checking to assure the edge is getting fair and smooth.
I've got several rabbet planes. One can be set up as a bull nose, cutting right to the end of the feature line.
A very thin strip of Alaskan yellow cedar will make a nice accent along the feature line.
There is a tiny little bevel at the end where the feature line intersects the next strip.
Obviously, staples are not an option on such a thin piece of wood. Masking tape will serve as a clamp while the glue sets up.
The same drill on the other side and then up front.
The next strip has a compound taper, against the intersecting strip, and then along the feature line.
I mark out where the bottom edge of the new strip crosses the top edge of the intersecting strip. This is the first taper.
I shape this until it fits pretty well.
The next taper extends from the end of the feature line back to where the bottom edge of the new piece crosses the top edge of the accent.
The fit starts with a good taper angle. Shaving back the taper will allow the strip to slide in farther.
When the glue dries, the staples can come out.
We now have the kayak all stripped up.
Step 6: Sanding and Fairing
After the stripping is completed, the surface has facets or flat bits on the face of every strip. Since the cross section of the kayak is curved, there is a ridge at the joint between the strips. The primary goal of fairing is to eliminate this ridge, creating a smooth fair surface.
The first step is using a heavy duty paint scraper. The scraper removes glue drips, but it also shaves off the ridge. I scrape the whole boat, concentrating my efforts on the ridges.
The paint scraper is sharp. I actually hone it on my diamond stone to get it wicked sharp. It should produce nice curls of shaved wood. Woodworkers may call it a shave hook, but I bought a paint scraper, so that’s what I’m calling it.
I hold the handle low with a firm grip and pull quickly and smoothly along the grain. The other hand lightly holds the blade to damp out chatter.
The scraper quickly and efficiently removes glue and evens out any irregularities between the strips.
I want to keep the feature line sharp and distinct so I am careful to not wreck it. I scrape on one side than the other, being careful to keep the blade flat against the surface.
Fairing is the process of smoothing out the surface to eliminate sudden changes in curvature. As such you want to work on long sections at a time. On average the strips should be pretty fair before you do anything. Long strokes of the scraper will maintain the fair curve while slicing off high bits.
I don’t want to dig into a small spot just because I see a smear of glue or something. Any glue left behind by the scraping is probably there because it is in a low spot.
The only way to eliminate a low spot is to reduce the height of the high spots surrounding it. By blending this in from some distance around the spot, the surface will stay fair while becoming smooth.
All this work popped the little bits of glue holding the deck to the forms. A couple staples secure it back in place.
Scraping eliminates most of the high spots but still leaves a rough exterior. We want to level out the ridges and blend them into a smooth, rounded surface. This is done with sanding. We want to quickly knock down the high spots by continuously moving a sander with a moderately firm pad, over the strips.
I use coarse sandpaper, like 40 or 60 grit, moving systematically over the surface of the boat, leveling each area completely before moving on to the next. Using finer grit with a soft pad would tend to conform into to the unevenness, abrading into the low spots while trying to leveling off the higher spots.
Watching the staple holes as a reference, I work on a one-foot section at a time, moving the sander back and forth from centerline to sheer followed by up and down from one side of the section to the other.
Being systematic this way, I know that the whole surface is getting sanded equally. I don’t want to stall out in one spot, trying to fix some issue I see, only to end up with a dip in the surface. I’ll go over the whole thing once fairly quickly, but trying to level it out completely. If I find that this first pass leaves areas still in need of more, I can come back over the whole thing again.
Consistent, systematic sanding, one way than the other while overlapping the sander about 50% each move helps assure a uniform amount of material is removed. If I were to try to correct apparent issues, or only sanding where it looks like it needs it, I would run the risk of dishing out some regions while leaving lumps in others.
Again, I want to leave the feature lines crisp, sharp and distinct. With a firm pad I can work right up to the edge without the pad drooping or flopping over the line. The coarse grit cuts quickly and efficiently, without a lot of pressure required. You can see the unsanded shiny spots quickly blend away into a uniform, level and smooth surface.
When I’ve completed below the feature line I lift the tool and place it back down above the line.
This Festool Rotex sander has a gear driven motion that ensures a consistent orbital spin. Some sanders will change speed as you change pressure. With some you may want to shut the tool off whenever you lift the sander off the surface to keep it from spinning up uncontrollably. This high speed spin up can dig a horseshoe depression into your cedar as you touch down.
For now I’m just doing the quick first pass on the deck. I have more work to do before I’m done with it, so I’ll do the finish sanding after I’ve completed it.
Until then, I’ll get the hull ready for glassing. Like the deck that starts with pulling all the staples.
Also like the deck, on the hull, I use the staple holes as a reference guide as I work systematically down one side and up the other.
Some of you were wondering what the holes were for. Now you know. I’ll use them again when it comes time to varnish.
People complain about how much sanding there is with strip-built boats. It’s true you do need to sand, but with the right sandpaper and a good random orbital sander it doesn’t need to take forever. For reference, the scraping and this first sanding took about half an hour.
I’ve actually stopped sanding at 60 grit and the boat easily passed the 5-foot-back inspection. But we’ll take it a little farther today.
The random orbital does a very nice job, but it can leave some cross grain scratches, and if you aren’t careful, you may end up with some subtle hills and valleys that are impossible to see at this point but become visible when the boat has a been finished in glossy varnish. A wavy surface under high gloss creates wavy reflections, and by then its too late to fix.
The long board I am using here bridges over low spots while grinding down high spots. The result is an extremely fair and smooth surface, while at the same time scrubbing out any cross grain scratches.
Wetting down the cedar raises the grain and can help highlight glue spots I may have somehow missed. This is your first chance to see the full glory of the wood grain on the boat.
I used 80 grit sandpaper on the long board. Now, I go over the whole boat again with 80 grit using a finer finish sander, the goal is to complete eliminate all the 60 grit scratches. Like the prior sanding I am systematic, using the staple holes as a guide as I work my way around the kayak.
I change the disk early and often. Dull sandpaper results in a lower quality finish.
I then hand sand with 80 grit working along the grain to reduce cross grain scratches and maintain the fair surface.
The final sanding is with 120 grit using the random orbital with soft contour pad and then by hand.
The best way to inspect your work is to run you hand over it. Your fingers can feel irregularities smaller than a human hair. If it feels good it is good.
Step 7: Fitting the Cockpit Recess
The recess is constructed out of plywood. Basically it is a little bit of Stitch and Glue in the middle of a strip-built project. I cut these parts out of 4-mm okoume plywood on my CNC machine, but they could be cut from aircraft birch plywood or veneer.
I decided to use a little puzzle joint to connect the recess riser to the sil.
A few dots of Cyanoacrylate glue is enough to spot weld the joints together.
A quick spritz of the CA glue accelerant makes it dry almost instantaneously.
I apply the glue to the bottom side so it will not show from the outside.
The top edge of the plywood should be lined up in a tight seam.
And secured in place with masking tape.
Little spot-weld dots of CA glue is enough to hold it until epoxying and fiberglassing a few days from now.
The tape can come off almost immediately.
To assure a tight fit into the deck along the visible edge of the recess, I am back-beveling the perimeter.
I drew up a pattern for the hole in the deck to accept the recess. This pattern is taped in place, using the forms as a location guide.
Those staple holes are proving more and more useful.
The inner edge of the template is traced on to the deck. In the last episode I did a rough sanding of the deck to make this part easier.
With the first side traced, I flip the pattern and line it up on the other side.
Now its time to cut out around the line. I don’t want to cut into the forms so I come in from either side. Then I join the cuts with a hand saw.
To assure a nice clean, sharp corner at the feature line I use my pull-saw.
Now comes the actual fitting. There are too many variables to have the paper pattern define a perfect fit right off. I need to work in on it.
I start by marking some basic references like the centerline of the recess.
The essential premise of the fitting process is looking to see where the recess touches the deck first, and then remove material from that part of the deck to make larger and larger tight sections until the whole recess fits snuggly into the hole.
The key to this process is patience. That, and finding the right tools.
I’m primarily using some little luthier’s planes with various bottom profiles and a Japanese float style rasp. I’ve also found that 40 grit sandpaper glued to sticks with different profiles are very useful. You want something that is precise, yet fast at removing material. Like the tools I’m using coarse sandpaper on a stiff strip is very accurate and fast enough to make noticeable progress with each stroke.
Sizing the hole is a constant cycle of testing the fit, shaving away tight spots and checking the fit again.
I don’t want to change the size of the recess piece, but it does need the bevel adjusted so the top edge is tight flush with deck.
As the fit at the front becomes more developed it is harder to check. Securing the recess piece in place with masking tape allows me to check the overall progress of the fit.
I mark the tight areas with a pencil so I remember where needs work.
With the front looking pretty good, I find I need to remove a lot of material at the back. I trace the back edge of the recess onto the deck.
I want to place an accent strip around the perimeter of the recess to highlight it a bit. I’m using the same thin strips of maple that I used on the other deck accents. This is glued on with carpenters glue.
Masking tape makes an excellent clamp for this thin strip.
At the front corner where the recess and front deck feature line intersect, I want a sharp angle in the accent.
I break off the strip a little long.
And then trim it to fit.
The color of the Okoume recess piece was not exacty what I wanted so I tinted it with alcohol based stain.
The tape comes off when the glue has set up.
I’m taping the recess back in dry, without any glue. I’ll spot weld it in with CA glue after its installed.
The CA glue will eventually get covered with an epoxy fillet. For now I just want to be sure the recess won’t pop loose while I’m doing other work.
I moved the cockpit area forms around a lot while I was fitting the recess. Now I want to be sure the shape is right to match the hull while I prepare other work. A little hot melt to hold the deck to the forms locks in the shape.
The deck is now fully assembled, it just needs a bit more sanding before its ready for fiberglass. The hull however, is already set for glassing. In the next episode we will drape the glass, wet it out with resin and apply a fill coat.
Until then, please post your questions to the comment area. If you are enjoying this series on boat building, please let me know by hitting like. To keep up to date on future episode please subscribe to my channel.
And just a reminder that plans and kits to build this kayak and other small boats are available through my website Guillemot-Kayaks.com.
Step 8: Fiberglassing the Hull Exterior
There is no definitive order of steps for a project like this. A lot depends on your personal schedule and when you have time to take on a particular step.
Back in episode 7 I finished sanding out the hull and it was ready for fiberglassing. Other than removing the unglassed deck, I have not touched the hull since I finished sanding. While the deck did not have any fiberglass on it, I was able to just lift it off and place it aside.
People are often intimidated by the prospect of fiberglassing. It is probably different than any other project you have done, but it is really just systematically making fabric wet.
After sanding the wood should be smooth and free of any splinters or snags. In the best of all possible worlds I would have a couple extra hands to help hold the cloth off the boat while I rolled it out so I was assured the cloth was smooth and straight. But its just me so I carefully roll the cloth down the length of the kayak.
I roll the cloth on a slight diagonal, starting with the left edge of the roll close to the sheer line and finishing with the right edge near the sheer. This sets the weave of the fabric on a slight bias relative to the keel and other sharp features and helps the cloth drape more easily.
While trimming the length I detour down the side a bit to conserve of the wider excess on that side for future use.
When the cloth is smooth and wrinkle free while dry it should end up smooth and wrinkle free while wet. Major wrinkles can be carefully pulled out by giving the cloth a gentle tug.
Remaining small wrinkles can be transported to the edge using a dry chip brush. Pay attention to the yarn direction in the weave. Wrinkles move along the yarns perpendicular to the orientation of the wrinkles. Aim for the closest edge along the yarns.
An hour or so before I came into the shop this morning I turned the heat up to about 85 degrees Fahrenheit or 30 Celsius. I want the wood, fiberglass and epoxy warm. Warm epoxy is lower viscosity or runnier which means it soaks into the fabric quicker.
Like most chemical reactions, epoxy cures faster the warmer it is. So, this means you want to make small batches and get them on the boat quickly.
I thoroughly mix a 4 to 8 ounce batch of epoxy and pour it directly on the bottom. Since epoxy generates its own heat as it cures, spreading it out in a thin layer will slow down the cure.
I use a plastic squeegee to spread out the puddle along the horizontal surface. I'm not trying to scrape the liquid off, just make the puddle more uniform on a one or two foot section of the bottom.
I then pull resin from this reservoir puddle down onto the side.
These plastic squeeges have two slightly different sides, the moulded side where all the edges are rounded and flat side where the edges are sharp. I start with the rounded side which is better at distributing resin.
Holding the squeegee at a shallow angle will pull resin from where its thick and deposit it where there is not enough. As I get to the bottom edge I go a little flatter to keep from pulling to much on to the floor.
When the initial area is wetted from keel to sheer I look to pull the puddle down the length, moving from wet towards dry.
The squeegee is a bit like a snow plow, pulling the resin along and creating a line of excess that is then pulled over the edge.
I work with intention. Each time I touch the squeegee to the boat I have a plan for what I'm trying to do with it. I want to pull resin from a shiny spot towards a white spot where there is no resin or towards as grey spot where there is not enough resin.
If you reach a point where your squeegee work isn't doing anything, it doesn't mean you aren't trying hard enough. There is no point in fussing with minor imperfections at this point. Don't try to make it perfect yet. You can fix minor issues later. Instead, it is time to mix more epoxy.
As you proceed towards the ends you will reach a point where the bottom isn't very flat any more. Trying to dump a big puddle of resin will just end up with a lot on the floor. At this point I use a chip brush to transfer the resin from my mixing cup to the boat.
The goal is to quickly get the epoxy out of the cup on to the boat. I don't need to saturate every square inch with the brush.
I stroke from wet towards dry and from the center down to the sheer, working to pull the glass tight.
I want to empty my mixing cup quickly. A large mass of epoxy in the cup will tend to generate heat, causing the resin to become less workable. Spreading it out on the boat gives you more working time.
In a warm shop the resin in your cup may only be good for 10 minute but still very workable after 40 minutes when spread on the boat. I want to empty the cup in less than 5 minutes. I mix small batches to match my work rate.
Once I have the epoxy on the boat I can use whatever resin is left in the brush to touch up dry spot on the previous area.
Working the squeegee from wet towards dry distributes the resin that I applied with the brush.
Wrinkles can usually be pulled from the wet area in to the white area where they will often dissipate, or off the edges where they don't matter.
If that doesn't work, I don't keep trying. Instead I do some yarn management. Finding where the yarns reach the edge of the cloth I give them a slight tug to pull the wrinkle flat.
Even though I did not initially brush on epoxy to the point where everything was wet out, there is plenty to saturate the cloth after I spread it with the squeegee. The squeegee is much more efficient at distributing the resin than the brush. I can quickly achieve full saturation without overworking the resin or introducing air into the layup.
The OCD watchers in the audience may be stressing about those drips. Don't. The wood is going to suck up some excess resin, I also want to allow any bubbles to float to the surface. A bit too much resin now will allow the wood to saturate and ease removal of any bubbles shortly.
And, no, I'm not going to try to fold over that excess cloth sticking out off the bow.
The time between the first dump of epoxy to fully saturated has been 20 minutes. I now turn down the heat in the shop to about 70° F or 20° C.
Now is when I worry about details. Because I worked quickly to get the cloth saturated, I have plenty of time to get the wetout perfect.
I've made a little slide into the edge of a paper cup. Using the sharp edge of the squeegee, holding it at about 45° to the surface with moderate pressure, I scrape off the excess resin. Sliding the squeegee edge through the slot removes the grunge.
This grunge cupping process should remove any glossy spots and fill any starved spots, leaving a uniform matte finish.
The squeegee pulls the cloth tight and presses it down on to the wood. Too much resin will make the boat heavy and it is actually weaker than a layup with just enough resin.
Where wetting out the cloth took 20 minutes, I spend another 10 minutes cleaning up the layup. I'll then let the epoxy cure for several hours.
After the epoxy has set up enough to be somewhat stiff but still a bit sticky I add a light fill coat. I will be adding another layer of cloth to the hull later in the build. For now I want to fill the weave just enough that I will be able to give it a light sanding later.
I mix a small batch of epoxy and distribute it on to the hull with a brush.
These puddles get spread around the surface with a squeegee. A little epoxy here goes a long way. I'm just working the resin into the texture of the fiberglass cloth.
Someone is saying: But, you just went through all that effort to remove excess epoxy, now you're putting it back on?
Yes, after we finished wetting out the cloth we then needed to get it tight against the wood for the strongest layup. Now, the epoxy has set up enough that it is bonded tight to the wood.
So I can now add resin to fill the weave.
But, but, but you just said you're adding more cloth later, why fill the weave now?
Because by the time I add that cloth, the epoxy is going to be fully cured. I'm going to have to sand to assure a good bond. If I leave the full weave texture, I'll immediately sand into the cloth, making it weaker.
Now to mess with you even further, I'm doing the grunge cup thing again. Scraping off the excess. I only need enough resin to fill the weave sufficiently to allow a light sanding that doesn't cut into the glass.
With the fill coat complete I'll turn down the heat and let the epoxy cure overnight.
The next day I can remove the hull from the forms.
Step 9: Fiberglassing the Deck Exterior
After the epoxy has cured on the hull it is a bit stuck to the forms. I work around the perimeter pulling the shell of the boat away from the forms. The fiberglass has already added a lot of strength and the hull can flex quite a bit without breaking.
With just one layer of glass on the hull it weighs almost nothing and is easy to lift off the forms.
Before glassing the hull I had temporarily removed the deck and placed it aside so epoxy wouldn't drip on it. Now that the hull has one layer of glass I flip the forms back over and put the deck back in place.
A little hot melt glue secures the deck to the forms and holds it in shape.
Back in Episode 7 I did an initial sanding on the deck and in Episode 8 I installed the recess. Now I need clean up the transition into the recess and do the finish sanding.
A long board levels out any slight waves in the surface that may have been created by the random orbital sander. It also removes any cross-grain scratches the power sander made.
I then go over the whole surface again with 120 grit sandpaper using a random orbital with a small orbit for a finer finish. A soft contour adapter pad between the sanding disk and the power sander helps conform to the surface.
I use the same back-and-forth followed by up-and-down sanding pattern I described in episode 7. Moving slowly, overlapping about 50% each pass while working in two different directions assures that the whole surface gets sanded evenly.
It is inevitable that with all the sanding that some of the stain on the cockpit recess is removed. To fix it I start by masking off the areas I don't want any stain.
In this case there is a fine pin-stripe between the recess and the rest of the deck that needs to be covered.
I apply another coat of stain to the spots that need it and then wipe the whole surface down with alcohol to blend the colors together.
The masking tape can come off immediately.
As soon as the stain is dry, I roll out the fiberglass cloth. It would be best if I had some help and could hold up the cloth off the boat while I rolled it out, but I work alone, so its easiest to support the roll on the boat.
Since this is a narrow roll of cloth, I just cut it off to length. I could save some material by laying the cloth on slight diagonal and nest the next cut in beside the end, but again working alone, this is easier.
The recessed coaming is a little difficult for the glass to conform to. By making some cuts in the cockpit area I can relieve most of the tension in the yarns that might prevent a smooth fit.
I always want to start applying the epoxy resin where the cloth will have the hardest time conforming to the surface. Dry cloth can be fairly easily distorted to drape smoothly, once it is wet with epoxy it is harder to warp the weave around complex shapes.
I dab the brush on to the surface to push the cloth down into the contours while transferring resin on to the layup. Wiping the brush at the point would pull tension into the yarns and possibly causing them to lift up off the recessed area.
I'm not trying to get the cloth wholly wet out with the brush. I am really just using the brush to get some resin from by mixing bucket on to the boat and start to stick the cloth where I want it. Once the epoxy is out of the bucket and on to the boat, I use my squeegee to distribute that resin around.
Once I've completely wet out around the cockpit area, right down to the sheer, I am ready to move on.
I can just pour out a puddle of resin and use my squeegee to move that epoxy around.
I work the squeegee from wet towards dry, in this way I pull the cloth tight and transport any wrinkle out towards the dry cloth or even better, off the edge of the boat.
With the tip of the squeegee I grab enough resin to fill where I'm working. Holding the it at about a low 20° angle with light pressure, I pull puddle of resin along, allowing it to soak into the fabric as I go.
To move resin farther distances over saturated cloth, I will increase the angle up to 45° to hold the resin as I pull, until I get to a dry spot where I lower the angle to help push it into the weave.
In this initial wet out I like to leave everything a bit over saturated where I can see some shiny puddles. This allows the wood to sponge up extra resin and reduces the chances of starved spots later.
Since I was quick about getting the initial wet out complete, I have plenty of time to come back and do the grunge cup. Holding the squeegee at a 45° angle with the sharp edge down and moderate pressure, I press the cloth down and pull off the excess resin to be disposed of by dragging the edge through a slot in the paper cup.
Once I've cleaned up all the drips and the cloth has a uniform matt finish with the weave texture clearly showing I let it cure for several hours, until the resin has set enough to hold the cloth firmly to the deck but still soft enough to promote a full chemical bond. Then I apply a fill coat.
Unlike in the previous episode with the hull, where I applied a light coat in preparation for another layer of cloth, on the deck I want to start it towards its final, smooth, shiny finish. This implies a fairly heavy fill coat.
The key to applying a lot of resin quickly without making a drippy, saggy, mess, is creating a uniform film thickness. To achieve this I work systematically on small areas at a time.
Since I used staples when installing the strips, I have a series of one foot sections defined. Dipping the brush deeply into my mixing pot I pull out fully laden brush. This epoxy is spread onto the surface with firm horizontal strokes back and forth between staple marks. Refilling the brush as needed.
I then switch to lighter vertical strokes from sheer to center line to even out the coat, pulling thicker spots to thinner spots.
The final step is gentle tipping strokes pulling from dry towards wet that pop bubbles and lift off excess resin.
With that section complete I move on to the next one foot section and repeat the 3-step process.
While it may seem exceedingly dangerous to take a blow torch to your fresh coat of epoxy, it's a great way to eliminate bubbles. The heat of the torch lowers the viscosity of the resin surface briefly and expands any trapped air to the point where the bubbles pop and disappear. The resin just isn't that easy to burn.
The cloth is applied and wet out and the fill coat is complete, now I'll just let it cure overnight.
Step 10: Making the Coaming
With the epoxy cured on the deck, I can trim off the excess fiberglass around the cockpit hole. First using a box cutter or utility knife to trim back the glass, followed by sanding with a 60 grit block to remove the residual bits of glass.
The coaming riser, or the vertical ring around the cockpit is constructed from the same strips I used to make the rest of the kayak. I cut a bunch of pieces about 2 inches long. These handy cutters easily lop off lengths of cedar.
Assembly of the riser starts at the front of the cockpit hole. I want two pieces aligned on either side of the centerline. Because of the curvature at the front, these pieces need a little bevel between them.
I work with a blockplane, shaving the edges and checking the fit until I have a tight seam.
When the fit looks good I run a bead of hotmelt to glue the first piece in place.
A square helps assure the first piece is straight. If these first pieces are out of whack, all the rest will be also.
I thought a little bright accent at the front would look cool, so I'm applying some carpenters glue to thin strip of maple.
I just rub it a bit to stick it in place, and the next strip will hold it there.
A little dot of hot melt where the strip touches the cockpit hole secures the next strip in place.
The rest of the coaming is mostly more of the same. Check the fit, bevel as needed, yellow glue between the strips and hot melt to the boat.
While this seems like a slow tedious ordeal, it has the advantage of using material you already have, and you don't need a separate building form since it is constructed in place. Compared to making a coaming form, cutting veneers and gluing them up into a lamination, this method is quite quick and efficient.
The hot melt glue holding these pieces in place is not very strong by itself. Eventually, this wood will all get wrapped with fiberglass and sealed with epoxy and will be exceedingly rugged.
I keep adding strips until I get to roughly the widest part of the cockpit, then I start up again on the other side.
If there is a downside to this system it is that the shape depends on the hole you cut. If you cut a sloppy hole, you will get a sloppy coaming. Take care fairing out your cockpit hole and be careful fitting the strips together and you will get great results.
When I get to the widest part of the cockpit again, I stop and fit the centerline strips at the back.
Eventually, the space left is narrower than one strip with a small gap remaining. I need to shape a little strip to fill that gap.
There is usually some hot melt glue squeeze-out. When the glue is cool and hard it is easy to cut it off with a sharp chisel. I just push the blade into the bottom edge of the blob.
Since I'm not too careful with the strip placement I have a ragged top edge to the riser. I mark it off a little taller than the finished coaming and cut off the excess.
I stick some coarse sandpaper to a flexible batten to sand the outside surface smooth.
Most of my sanding tools have built in dust collection. Instead of blowing all this cedar dust into the air, it is safer to vacuum it up.
I want to run a strip of masking tape around the cockpit one inch away from the coaming riser. I could just draw a line with a pencil or scratch a line with a scribe, but that would show up later. Instead I'm temporarily running a strip of tape directly next to the riser, then using that as a guide run the actual line of tape that I want.
Before I lay down a fillet of thickened epoxy between the deck and the riser I brush some unadulterated epoxy onto the riser. This allows the cedar to suck up as much resin as it needs without drawing it out of the fillet.
I then mixed some wood flour into the epoxy, creating what I call dookie schmutz. This is loose enough to flow out of a cake decorating bag, but stiff enough to stay where I put it.
You can also use a heavy duty zip-lock bag to neatly dispense a uniform bead of the filleting schmutz into the corner between the deck and riser.
The fillet is shaped using a tool with a nice radius at the end. This could be a tongue depressor or plastic picnic spoon. I'm using a little plastic spreader.
I find I get the smoothest fillets when I use a long, uninterrupted pull with the tool. Every time you start and stop there will be a little bump.
After the fillet is shaped, I come back and clean up any excess schumtz on the deck or riser, being careful not to poke the soft fillet.
I'm going to lay fiberglass right down on top of the fillet. I need bias-cut cloth where the weave is on a 45 degree angle to the axis of the strip of fabric. These strips distort easily, which is the whole point, but it means they should be handled gently.
A three-inch-wide strip is cut out of the same 4-ounce cloth I use on the rest of the boat. After the strips are cut, I carefully fold them, doing my best not to stretch the pieces.
Over on the boat, I continue to be careful about pulling on the bias-cut cloth. I need the cloth to distort in order to wrap up the coaming while also making the turn around the cockpit.
I gently pat the cloth down into the fillet. I want to coax the weave into the needed shape without messing up the still-soft fillet. Stroking the cloth lengthwise before it is tacked in place with some epoxy may create a pull or wrinkle.
It takes several lengths of the cloth to get all the way around. At the end I need a patch for the last bit. I overlap each end a couple centimeters or about an inch.
Since I completely wet out the fiberglass using the brush the fabric soaked up more resin than it really needs. I lightly squeegee the cloth to scrape out the excess epoxy and slide the squeegee through the slot in my paper cup to clean the edge.
Sliding a gloved finger over the still-soft fillet helps reshape the schmutz.
After the epoxy has set up to a leathery stage I can trim off the glass. A brand new blade in my knife combined with a light touch helps me cut through the new glass without scratching into the old.
I cut just beyond the edge of the masking tape and peel the fiberglass off with the tape.
The next day the epoxy has cured and its time to make the coaming lip. Made from a bunch of 1/16-inch thick mahogany laminations I need 12 pieces cut to length. The easiest way to measure the length is to wrap a piece and break where needed.
I assemble my lamination stack dry, including a maple accent in the mix.
You can just make out some clear blue tape I've wrapped around the coaming so glue doesn't stick to the riser.
Starting at one side of the front, I can proceed to clamping the stack around the riser. I take care to keep the stack straight and square. The thin laminations have no problem making the bends.
Its too hard to try get the ends lining up exactly, but I don't want them to interfere with each other so I just lop them off a little short.
After the laminations have been loosely clamped in place I shift the clamps and add some more while making sure the stack is straight and tight.
I'm not going to add any glue between the laminations. Instead I'm just going to paint the whole thing with epoxy and let the resin soak between. Using heat to lower the epoxy viscosity, capillary action will get enough glue between the layers to hold them together.
I remove a section of clamps, heat the area, brush on some epoxy, heat it some more, then replace the clamps.
After its all slathered up with epoxy, I go back and double check that the laminations are straight and level and add more clamps as needed.
When the epoxy has cured, I remove the clamps. The clear blue flash tape allows the lip to pop off the coaming and I peel off the tape.
Removing the glue-up allows me to clean the surface of the lip. I plane it flat and smooth on both sides.
The underside will be hard to reach after the coaming is complete, so now is a good chance to reinforce and protect the bottom face with a layer of glass.
I use bias-cut strips again as they are able to follow the bend of the lip.
When the epoxy has cured I clean up the excess glass and epoxy drips along the edges and prepare to install the lip. The outer face of the riser has been scuff sanded to improve the epoxy bond.
A little gauge stick serves to assure the lip is a consistent 3/4-inch above the deck.
I eyeball the alignment before loading up more clamps.
At this point the lip gets spot welded to the riser using a small dot of CA glue every inch or so.
A quick spritz with the accelerant hardens the glue almost immediately and I can continue working.
I trim the ragged ends of the lip at the front with a cut that is tangential to the riser.
A sharp chisel works well for cleaning up the cut ends.
Final tuning is with a plane and sandpaper.
Like the rest of the lip, I want to laminate up the front bit in place, remove it, clean it up then do the final installation. This starts with some flash tape to keep the glue from sticking.
I have a bundle of short thin mahogany strips that I will stack up, clamp in place, and then glue.
Instead of epoxy, this time I'm using a very low viscosity CA glue that I hope will soak down between the layers and glue them solidly together. The whole coaming will eventually get another layer of glass and epoxy, I just need something strong enough to hold it together until then.
After a quick cleanup, the front bit gets fit back in place.
Now it can be glued down.
And the shape can be blended into a nice smooth curve.
Before I trim off the top of the riser, I work on cleaning up the inside surface. This prevents me from rounding over the top edge by mistake.
Now I can cut off the excess riser that extends above the lip.
I use a block plane, various rasps, and sanding to level and clean up the riser edge and lip surface.
Now I repeat the process on the bottom edge of the riser.
It doesn't work everywhere but a router with a round-over bit can create a good, consistent radius between the deck and the riser and the riser and the lip.
The outer edge of the lip needs to be rounded over. This can be done with sandpaper, but I find modified scraper with a little grove edge on it, is very quick and efficient.
With the sanding done so there are no sharp edges, the coaming is ready to be glassed.
Step 11: Sanding and Glassing the Hull Interior
Back in step 8 I glassed the exterior of the hull, and then step 9 I removed the hull from the forms so I could glass the deck. Now with the exteriors of both the hull and deck reinforced with fiberglass, I no longer need the forms.
I remove the spacers and slide the forms off the strongback so I can put everything away until I want to build another.
Cleaning up the interior is where the scrapers really come into their own. The concave sections make heavy sanding with a random orbital sander awkward, but a contoured paint scraper can quickly and efficient get into small spaces to clean out glue and shave away any imperfections.
It is important to remember that we are fairing, or trying to make the surface more smooth. That means we are working on large areas, not small ones. So when I see a glue spot, I take a long pull, beyond, through and past, that spot. If I were to try scrubbing out just the spot, with short back and forth motions over the glue, I would end up chewing an undesired low area instead of creating a smooth fair surface.
The blade only cuts on the pulls stroke, so I put my effort into pulling. By lifting the blade on the return I protect the tool from getting dull doing something that doesn't help move progress forward.
I sharpen my scrapers before each use to make sure they make a smooth clean cut. A quick pull with light pressure should shave off a thin curl of wood. If you get a pile of small, dusty chips, you probably need to sharpen it more.
A sharp scraper quickly makes gratifyingly large pile of shaving, but it is not really removing a large amount of material. By selecting a scraper shape that matches the sectional shape, it is really just blending the flat faces of each strip into a smooth, continuous curve.
A soft contour pad on a random orbital sander wants to conform to the existing surface and is inefficient shaping the facets formed by the strips into a hollow, rounded surface. By having a selection of different shape blades it is possible to very quickly prepare the interior so less time is needed with sanding.
When the shavings are no longer coming off the blade in clean curls, I'll touch of the edge with a diamond stone.
I had previously done a rough trim of the fiberglass with a utility knife. In preparation for adding an accent strip, I want to clean the top edge of the sheer line with a block plane, creating a smooth, flat, fair edge.
The accent strip is a 1/16 inch thick strip of maple glued directly to the top edge of the hull sheer. I could have installed this way back in Episode 3 when I started stripping by gluing it to the sheer strip, but I was thinking I might stain the hull. Adding the accent strip now would have avoided staining it to maximize the contrast.
With a thin bead of glue on the top edge, I press the accent strip down and hold it with masking tape.
I start with widely spaced bits of tape to get the alignment right. The tape can be pulled quite tight to assure good clamping pressure.
Once the strip is in place, I come back with more tape to fill in the gaps for a tight fit down the full length.
The same process on the other side.
With a tight fit, the carpenters glue is tacked up sufficiently in less than half an hour and all the tape can come off.
After scraping, the interior is in pretty good shape. At this point sanding will even out the texture and remove the tool marks. I add a soft foam contour pad to the sander to help it conform.
Using 60 grit paper on the 5 inch sander I can work on the wide, flattish bottom of the kayak, between the chines. The chines are too hard to sand across, and above the chines is too narrow for this sander. But I can sand farther through the softer chines near the bow.
An initial sanding will reveal any spots that would benefit from a bit more scraping.
Your hands are the best tool for detecting surface irregularities. If you feel any ledges or overhangs in the strips, a quick hit with a sharp scraper will easily remove it.
There are places the power sander is too big or imprecise to work effectively. Some coarse sandpaper wrapped around a block of foam does a very good job cleaning up in the chines, sides and ends.
With sanding complete, I thoroughly clean the interior in preparation for fiberglassing.
I don't want drips of epoxy running down the side of the hull that I'll have to remove later. Some tape along the outside edge should catch most of the mess.
The Petrel Play has a hard chine behind the cockpit. This is potential stress point in the finished boat. To distribute the load across the chine, I want to add a fillet and some reinforcement.
The fillet is epoxy thickened with wood flour, to make what I call Dookie Schmutz. Using a cake decorating bag, I dispense a worm of schmutz into the corner of the chine.
While I'm at it I add a fillet in the stems to ease the wrapping of the glass in the ends.
The fillet is shaped using scrap wood with a rounded end.
The next bit of chine reinforcement is a strip of bias-cut fiberglass crossing over the chine to cover the fillet.
I lay the strip directly on to the still wet dookie schmutz and then wet it out with epoxy.
Bias-cut strips are susceptible to pulls and distortion, so I first tack it down with gentle dabs before working it harder with the brush.
While working alone, the roll of fiberglass is easier to handle across the boat than lengthwise, and it is also more efficient with the cloth. I don't do this on the outside because I don't want to create stepped seams that need to be sanded out. On the inside, the overlaps are less noticeable and can be aligned with bulkheads.
I overlap each piece of cloth at least an inch to create a strong seam.
At this point, I'm just loosely draping the cloth, leaving enough overhang that there will be enough to fit down into the hull.
I want the overlaps to be directed towards the ends, so when I pull resin from the middle towards the stems, I won't snag the loose edge of the next overlapping piece.
Being careful not to snag the delicate cloth on any sharp bits along the sheer, I gently let the cloth drape down into the hull.
Eventually, I'll need to trim the ends to fit into the stems to prevent the glass from bunching up. For now, I just fold the end back a bit.
Again, I work carefully to not snag the edges. Before pushing the cloth down, I'll lift the edge off the side so it doesn't scrape as it nestles in place.
Some little snags and distortions in the cloth aren't the end of the world, but I try to keep it neat.
With the cloth nestled into the hull, I trim off the excess glass at the edges. The weight of the cloth hanging over the edge can create bubbles along the sheer later on. Since I haven't finished the fit all the way to stems yet, I leave extra at the ends.
Proceeding directly to wetting out the cloth. I want to get the epoxy out of the large mass in the mixing tub as quickly as possible to slow down the cure giving me as much working time as possible.
From a long puddle poured down the middle of the boat, I quickly pull a bit of resin all the way up the sides. I'm not initially interested in making it look perfect. Instead I want to get the epoxy spread out and distributed.
Spread out epoxy cures more slowly than epoxy in a large mixing pot. Working quickly initially allows me more time to get a neat final finish.
After I've pulled that first puddle up the side, I start moving any remaining excess lengthwise. I want to move in a consistent front down the length of the boat.
I don't need to scrape all the excess away, but do I want to use the epoxy efficiently, so I try to spread it as far as I can without getting obsessive about it.
If you find yourself doing something and it doesn't make any difference, stop doing it.
About a minute twenty seconds after I poured that first puddle, it is spread out. Time to mix some more epoxy and move on.
With my sticky gloves I didn't get a camera on the trimming the glass in the stem area, but I cut a slit down the middle to the base of the stem and trimmed the glass so that it overlapped about an inch on either side.
After the first section I wet out has had a chance to soak in for a while, I come back and scrape off the excess resin.
When you first experience this it will drive you batty. Those bubbles are what I call bridging. As I press the squeegee into the cloth and pull from the keel to the sheer, it pulls the glass tight causing it to lift out of the chine.
Don't panic. It is going to happen again and its easy to fix.
The bridge appears because there is not enough fabric to fit in to the concave surface. You fix it by feeding a little more cloth.
I'm scraping the excess resin in to a slit paper grunge cup in the same way I did in episodes 10 and 11. When I was glassing the convex exterior surface it stretched the cloth tight against the exterior. With the concave interior you will get bridging. Learning to accept this and understand it will help your sanity.
If you realize that bridging will happen when you pull cloth out of a concave surface you will understand you don't need to struggle to fix it every time it happens. Do your work, then come back and deal with the bridging later.
You don't want to pour a huge puddle of epoxy down into the ends of the boat where it will be hard to dig out. Instead use a brush to apply resin to the surface and then use your squeegee to spread it around.
The stems can use a little reinforcing to cover any gaps made while trimming the cloth to fit into the ends. A strip of bias-cut cloth applied along the keel and up into the ends does the trick.
Again, bias cut cloth distorts easily, so a gentle touch as you coax it into place will keep it from getting away from you.
Carefully press the strip into place with the brush until it is centered and stuck down before completing the wet-out.
After the stem strips were installed, I let the epoxy set up for a couple hours before adding more resin for a thin fill coat.
I mixed up a small batch of epoxy and poured all into the bottom of the boat. I then spread it around the whole interior with a squeegee before scraping off the excess into a grunge cup.
Step 12: Glassing the Coaming and Deck Interior
The cleanup of the deck interior proceeds in the same manner as the hull. I start with good sharp paint scrapers.
I select a scraper edge that best matches the sectional shape of the deck at the point I'm working.
The deck is resting in some cradle forms that match the deck shape. Some tape keeps the light weight deck from flying all over the place as I work.
This Petrel Play design has a tight radius at the deck edge which the tear-drop scraper fits into nicely.
I can't use a power sander everywhere on the interior, but I will do as much as I can.
An up-and-down, then back-and-forth sanding pattern does a good job of leveling all the strips equally.
Its amazing how flexible the shell is at this point. It is just 3/16-inch of cedar with glass on one side, but it is already pretty strong.
I do as much as I can with the power sander, adding a contour pad to help with some of the tighter curves.
I then touch up some spots with a scraper and finish up the sanding with some 60 grit sandpaper wrapped around a shaped piece of foam.
Back in Episode 11 I built up the cockpit and coaming. I double check to make sure it is all sanded out and ready for fiberglassing.
Wrapping fiberglass around the coaming is an excellent demonstration of the capabilities of cloth that has been cut on a diagonal or a bias cut. With the yarns running at a 45° angle to their length bias cut strips distort easily, so handle them carefully.
A thin coating of epoxy on the coaming helps hold the strips of cloth in place as I get them situated.
With bias-cut cloth you need to be careful not to tug or pull at it because doing so will make the strip narrower. By carefully unrolling the cloth and gently patting it into position, I will have enough width to wrap around the underside of the coaming lip.
I'm trying to position the cloth on the vertical part of the coaming, with enough fabric above to wrap out over the top of the lip, then tucking back underneath the lip, but not so much that it will need to go down the outside of the riser. I also want enough to wrap around the bottom of the coaming to the underside of the deck.
With the strip of cloth positioned, I make sure it is well stuck to the coaming riser.
Now I can fold the top edge out over the top of the lip, pulling the cloth from the inside out towards the edge.
It looks like I have more than I want hanging out on my side of the coaming, so I pull it back it in and down the inside of the riser.
Around the front I don't have enough, so I pull a little up. This creates a little bunching, but I can move some of that to the underside of the lip.
A bit of resin applied to the underside of the lip will help tack the cloth in place.
Now I start folding the edge of the cloth under the lip. A bent acid brush comes in handy for reaching the bottom side.
It takes some patience. The cloth will not stay until there is enough resin on it and the lip to make it stick in place.
So, initially it is a process of carefully stroking from the outer edge in towards the riser with a wet brush getting more and more resin on the cloth.
Eventually, visible progress is being made. The cloth sticks and stays adhered to the underside of the lip.
If the edge of the cloth wants to start wrapping down the outside of the riser, I pull it back to keep it on the lip. The excess is then pull back over the top and down the inside of the riser.
With the first piece in place, I renew the epoxy on the rest of the coaming to prep for the next section.
The next section overlaps the prior about 1 inch.
I've got a short bit remaining that does not have glass on it yet. I measure a piece to fit with about an inch overlap on either end.
The last bit of glass to get epoxy is the stuff hanging down below the coaming. The easiest way to get this is to flip the deck over.
I want to pull the glass tight as I fold it onto the underside of the deck, so I pull the brush from the edge out over the deck.
After I've finished wetting out the glass, I scrape off the excess with a squeegee and grunge cup.
I'm going to proceed directly to glassing the inside of the deck, but first I want to make a fillet between the cockpit recess and the deck to reduce any stress riser in this area.
A cake decorating bag or zip-lock makes quick work of distributing the dookie schmutz into the seam.
While I'm at it, I add a fillet to the foredeck feature line.
The filleting mix of epoxy with wood flour is shaped using a rounded piece of scrap wood. This eases the transition from the coaming recess to the deck.
I clean up any squeeze out with a squeegee.
Without waiting for any of the epoxy to dry, I go directly to laying out the fiberglass.
I placed the back edge of the first piece of glass directly behind the cockpit. This way when I add the piece to cover the stern, I end up with a doubled up section behind the cockpit to help support the load of climbing in and out of the kayak.
I always wetout around the cockpit first because this is the hardest part and any wrinkles that develop are easier to deal with before the rest of the glass is saturated with epoxy.
Trimming the scrap glass out of the cockpit hole reduces the tension on the yarns winding over the various contours of the cockpit recess.
A couple darts around the cockpit will help allow the fabric to drape down onto the coaming riser.
The trimmed edge of the cloth is wetout to create a second layer on the coaming.
Once the cockpit area is dealt with we can now get on to the easy stuff.
Pulling from the puddle at the center, up the side, I want to wet out all the way to the sheer.
Like at the chine in the last episode, I do get some bridging at the feature line. Instead of stressing about these bubbles now, I ignore them. Time spent now fussing with minor issues result in the epoxy setting up more and making it harder to deal with any issues later.
Trimming off the excess glass prevents the sagging edges from lifting the fabric off the interior.
I dump the resin in the middle and spread it to the edges with the squeegee. The resin-rich layout at this point allows the wood to soak up its fill, preventing starved areas later.
I'm doing an initial scraping to even out the resin.
There is no point in fixing the bridging until I've completed the scraping.
With the wet out complete everywhere I do a final grunge cup round, inspecting for issues as I squeegee off any remaining excess resin.
I'm not showing the light fill coat like I did in the previous episode because I neglected to record it.
Step 13: Hatches, Deck Hardware and End Pours
I usually cut the hatches freehand by tracing a pattern on to the deck and cutting it out with a jigsaw, but the back deck of the Petrel Play is nearly perfectly flat. This allowed me to make a template on my CNC machine then cut the hatch with a router.
I'm using a tiny 1/16-inch router bit in my small plunge router and cut the hatch in a couple passes.
The hatch sill is made from two parts. A spacer, that has the same inner diameter as the hatch, and the lip, with a 3/4-inch smaller inner diameter. They both have the same outer dimension about 1/2-inch larger than the hole.
I dry fit the parts to make sure everything is the right size and fits well. This also allows me to practice getting everything aligned before they are sticky with epoxy.
I want to glue the spacer and the lip together before gluing the assembled sill into the boat. This way I can clean up any glue squeeze out and sand the edges before final assembly. Some tape on the deck interior lets me remove the sill after the glue cures.
The masking tape contains the mess and nothing sticks to this clear blue flash tape.
Assembling the sill in place on the deck assures that the finished piece matches the slight curve of the deck.
With the spacer in place I apply some epoxy to the surface. I've added some colloidal silica to the epoxy to make thicker glue.
I also apply glue on the mating surface of the lip. Gluing both sides assures there are no pin holes to allow water into the finished hatch.
There is no such thing as too many clamps. I want a tight seam all the way around.
This kayak is getting some of my recessed deck line fittings. These are mounted through egg shaped holes in the deck. I cut the holes using a template and a router.
The slot for the retractable skeg control is installed in a similar manner.
The recessed fittings need a little shaping to fit to the curved deck surface.
I scuff up the fiberglass for a stronger glue bond.
The fittings will get a layer of fiberglass over the inside for strength and protection. Masking tape around each fitting contains the mess.
Each hole and fitting is coated with un-thickened epoxy that will soak into the wood before applying epoxy thickened with wood flour as the final glue.
The skeg control slot is installed in the same manner.
Off camera I rounded over the edges of the hatch sill then glued it in place. Now I want a layer of fiberglass to reinforce it and encapsulate the wood.
I use bias cut strips to conform to the shape and contours.
It is my goal to have a layer of fiberglass cloth over every bit of wood in the whole kayak. While varnish provides good protection. The thickness and reinforcement provided by the fiberglass and epoxy followed by varnish creates a layer of armor that cannot be matched by a couple coats of varnish.
This often means a lot of extra work. Getting the glass to wrap over these deck fitting bumps is a hassle. But it's a lot easier to do this now than to replace a rotten piece later because someone failed to maintain the kayak properly.
Cheek plates help keep your butt centered in the kayak. They also provide a convenient place to mount the backrest. I weld the plate in place with CA glue.
CA glue by itself isn't strong enough so the plates are reinforced with fillets and fiberglass.
I also added some carbon fiber for additional strength.
Fillets and glass on both sides of the plates.
A traditional endpour involves standing the kayak on end and pouring some resin in to make a solid tip.
Instead I'm going to make a little dam at each end out of an old squeegee to create a reinforced place to mount a grab loop.
The dammed volume doesn't need to be large, just big enough to drill a hole through.
I added some quartz micro-spheres to the epoxy to make a thick lightweight mix and then a little graphite powder to darken the color.
After lightly scoring the fresh fiberglass and epoxy with a sharp utility knife I peel off the excess fiberglass.
On the outside of the deck, the deckline fittings and skeg control slot are planed, rasped and sanded flush and smooth.
The outside of the fittings are protected under a layer of fiberglass.
The excess glass is trimmed then a fill coat is added.
After the epoxy has set up, the remaining glass is trimmed, and the ragged edges are sanded smooth.
Over on the hull, the end-pours are cured and the dam can be popped out.
I rasp off the excess material to allow for a snug fit with the deck.
This little jig measures a consistent distance down from the sheer while providing a horizontal reference as I drill through the end-pour.
I start with a quarter inch pilot hole going all the way through.
Then I make a large countersink on either side.
I finish with a 3/8-inch hole, going half way through from one side then completing it from the other side. This prevents blowout while keeping the hole in the right place.
The deck and hull now almost complete and ready to join together.
Step 14: Interior Varnishing and the Deck-Hull Joint
The hatch will have a gasket to provide a seal. That gasket needs a smooth surface to seal against. Since the thin interior fill coats leaves the texture of the fabric showing, I need to apply another fill coat around the perimeter of the hatch.
I mask of the middle of the hatch and then paint on epoxy with a little colloidal silica added to thicken it slightly. While I'm at it I'm sealing the end grain around the hatch edge.
A little blast from a heat gun pops bubbles and levels out the surface.
When the epoxy has tacked up a bit, I peel off the masking tape.
I need to scuff up the interior to help the varnish stick. Since I want to keep the weave texture of the glass fabric, I can't just sand everything flat. I cut a circle of synthetic steel wool and use that on my small random orbital sander. The wooliness of the material does a good job of de-glossing the epoxy surface without sanding out the texture.
Both the deck and hull get the same treatment.
I don't want to get varnish along the sheer line because I'm going to have to epoxy in fiberglass tape along the deck-hull seam, so I mask off the top edge.
The whole inner surface below the tape will be coated in varnish. While the interior will not see much Ultra-violet light, the varnish is still good protection for the epoxy. Since the ends of the kayak will be almost completely inaccessible when completed, now is the time to prevent problems later.
I use the same brushing pattern for varnish as I did for the heavy epoxy fill coat discussed in episode 10. First I apply the varnish with heavy horizontal strokes, then level it out with lighter vertical strokes, followed by very light horizontal strokes to tip off the bubbles.
At the chine, it can be helpful to break up the vertical strokes into two sections for above and below the chine.
Irregular shapes such as the deck fittings are drip producers. I carefully work my way around the bump using my brush to sponge up excess varnish at the end.
When the first coat has dried for about 10 hours, I apply another coat right over the top.
After those two coats have dried overnight, I de-gloss again.
A tack cloth cleans out any accumulated dust.
A third coat of satin varnish provides the final finish for the interior of the kayak.
I left the same tape on for all three coats.
The top edge of the sheer still has a bit of a rough edge left over from the interior glass, plus there are some puddles of epoxy here and there. I need to make the sheer fair and smooth to ensure a tight fit between the deck and hull.
I use a block plane, rasp and or a sanding block to clean up the edge. I don't want to round it over, but instead make a pair of nearly matching bevels on the hull and deck.
This will require some test fits. Here I see the end pour needs to shaved down a little.
With the ends fitted well, I want to check the fit along the length. I temporarily tape the seam together looking for tight spots. I mark these with some blue masking tape so I can find them when I take the deck off again.
Satisfied with the fit, I clean out the interior then lay in some painter's masking film. This has tape along one edge and a lot of static cling to hold it in place. This will keep me from getting much epoxy on my fresh varnish.
A strip of green tape above the masking film defines the edge of the fiberglass seam tape. I'll be able to peel this up after laying in the seam tape on one side, without peeling off the masking film before seaming the other side.
Denatured alcohol cleans off any dust or contaminants where I'll be epoxying down the interior seam tape.
I mix up some epoxy thickened with wood flour to apply to the tops of the endpours. This will secure the deck down at the ends.
Now I start clamping the deck to the hull with glass-reinforced packing tape.
The thing that is going to hold the sheer line seam in alignment is friction. This is created by forcing the deck down on to the hull with the tension of the packing tape. What I'm saying is: inorder for this to work, the tape must be very tight.
I use a tape dispenser that lets me really pull hard on the tape, stick it down to the hull while I'm pulling on it and then easily cut the packing tape after it is in place.
If I cannot reach inside the boat to push the seam into alignment, I can use a thin putty knife to lever the seam into position while I tape it tightly together.
The hull and deck are really quite flexible, so even if they don't align perfectly initially, you can usually bend them to line up. While the tape might have trouble holding initially, with enough tension and friction between the sheers, I've successfully joined together badly mismatched pieces.
Depending on how easily the seam comes together, I usually end up with tape every 4 to 6 inches or 10 to 15 cm.
While applying epoxy to the inside seam, there is bound to be some that leaks out. A strip of masking tape along the seam will contain it, but to avoid large bumps I want to apply the tape wrinkle free and smooth.
I find it helps to apply it to the hull and then fold it up on to deck after.
We want gravity helping the task of taping the inside seam, so I secure the kayak up on edge.
A little tape assures it doesn't do something unexpected.
The inside seam will be reinforced with 3-inch-wide pre-woven fiberglass tape. I measure a length from about 6" shy of the stern to 6" short of the bow.
A piece of masking tape placed to align with the center of the cheek plate in the cockpit gets marked with an arrow point to the bow to help get the glass back in the correct spot.
I roll or fold up the strip of tape to transfer it from the boat to a table covered with a piece of waxed paper.
The strip of cloth now gets completely saturated with epoxy. The cloth is actually a 9 ounce fabric that takes a while to soak up the resin, so I brush it on heavy and give it time to soak in.
While the cloth is absorbing the epoxy, I brush more resin on the seam. I reach as far up as I can with my arms and then use a brush screwed to the end of a stick to spread the resin up into the end.
I roll up the saturated tape to transfer it back to the kayak. I roll from each end towards the middle where I marked the masking tape with the cheek plate locations.
Bringing the roll over to the boat, I align the tape behind the center of the cheek plate, making sure my arrow is pointed towards the bow. I can now roll out the tape along the seam as far as my arms will reach in each direction.
When I get beyond my arms reach, I again switch over to the brush on a stick. I just want to unroll the tape down the seam between the green masking tape. This takes some patience. You can steer the roll one direction or the other by pushing it with the brush.
Mistakes happen. Depending on your personality you may find that cussing helps. Others may try to manipulate the tape with the brush in a fruitless effort to make the situation right.
The solution that works is to just pull the cloth back, re-roll it and install it again. The epoxy is setting up while you fuss around, the quicker you get on with the show, the better off you will be.
This time I checked there were no snags before pulling back the stick.
With the tape properly in the bow I now want to smooth it out and make sure its well stuck down by brushing on a bit more epoxy resin.
Now to do the other end. Hopefully, it will go more smoothly this time.
I let the first side set up sufficiently that it won't fall off when I flip the kayak over to do the other side.
Here, I'm marking the center of the cheek plate and reference arrows to guide the strip of tape back to the right spot after it has been wet out.
The marks on the tape will be hidden behind the cheek plate and won't be visible in the finished kayak
I had a few issues again in the bow, but with patience and persistence it worked out fine.
We just about have something that looks like a kayak.
Step 15: Outer Stems and More Fiberglass
When the interior epoxy is fully cured at the deck/hull joint, you can peel off the masking and packing tape.
I'm going to laminate some hardwood on to the stems at each end of the kayak. The first thing to do is clean up the ends and make a smooth flat surface to glue against.
It is important that this surface is square to the centerline. I check this by holding the flat sole of my plane against stem and sight down it to see if the face is tilted one way or the other.
By holding the plane at a skewed angle to the cutting direction I have more control over the face angle it is cutting so I can make adjustments as I go.
While shaping around the knuckle it is easier to make a straight cut then knock the corners off than it is to try to keep the blade cutting while wrapping around the corner
I'm planing down the stem until I have face about 1/2-inch wide.
I didn't get the installation of the skeg box on video. It was inserted through a slot in the bottom, offset from the centerline by about an inch. The inside was glassed in much the same way I did the cheek plates in Episode 14. What's left is the bottom edge sticking out through the hull. This needs to be cut off flush to the surface.
The masking tape helps protect the bottom from getting scratched up as I use a Japanese pull saw to cut off the protruding box.
I mask off around the ends to contain epoxy squeeze out as I laminate the outer stems.
The exposed end grain of the strips soaks up epoxy easily. I paint on plain epoxy to prevent a starved joint.
A stack of 1/8-inch thick hard wood lamination are slathered with epoxy thickened with colloidal silica.
I thicken the epoxy being applied to the boat with wood flour for a better color match.
Everything here is slippery with epoxy. The first goal is to get the stack in about the right place and get it under control with some bits of filament tape.
The thin laminations should be easy to bend. If they have trouble, thinner strips will make it easier.
Once the laminations are under control, stretch wrap makes a great clamp. More wraps make more pressure.
After the epoxy has cured the stretch wrap is cut off.
Now, we plane off everything that isn't kayak. I want a smooth continuous surface between the outer stems and the rest of the boat. By holding the heal of the plane against the kayak, while the blade cuts away at the excess material, I won't over bevel.
The side of the kayak is always the guide. I'm planing off the wood that sticks above the surface of the kayak.
I'm knocking down everything thats sticking up.
When I get close to cutting into the fiberglass, I switch over to sanding to get the smooth, uninterrupted surface I'm looking for.
I sand along the sheer line to blend the deck and hull together.
The existing glass has a light fill coat on it. I can sand the surface to eliminate the gloss, but I don't want to sand into the glass. I'm just roughing the surface and knocking down high spots.
I'm going to add a layer of fiberglass to about 1-inch away from the sheerline. The green tape is 1-inch and the blue is a little bit above it. The bottom edge of the blue tape is folded under so it allows epoxy to drip off without running onto the deck.
Since the wood here is already sealed with the prior layer of glass, I won't need quite as much epoxy to wet out the cloth, and I don't need to worry about starved spots occurring due to epoxy soaking into the strips.
The stems are too plumb to effectively wrap the cloth around, so I just cut off the cloth, leaving a little bit hanging over.
I don't need to wait for the wood to soak up any resin, so I can go immediately to scraping off excess resin into a grunge cup.
After the epoxy's set up for an hour or so, I trim off the excess glass above the blue tape.
I want to control the mess from the fill coat, so I apply another strip of blue tape and fold up the bottom as a drip edge.
This is a heavy fill coat, meant to eliminate most of the fabric texture, so I use my technique of applying the resin with firm horizontal strokes, leveling with lighter vertical strokes and tipping off bubbles with a very light horizontal strokes.
The stems do not yet have fiberglass over the leading and trailing edges. I now lay down a length of bias-cut cloth to cover the stems and run a bit down along the keel line to absorb abrasion.
I dab it in place to help it fold over the radius of the stem.
A quick blast with a blow torch pops bubbles and levels the resin.
The hatch is flush which makes it hard to lift. A little thumb-dent creates a spot to get a finger under the edge to open the hatch.
I have a small sanding drum I can chuck into my drill. This quickly cuts an indent into the deck along the side of the hatch.
The hatch cover will be secured in place with a couple straps of webbing. The webbing is attached to the deck with stainless steel bolts inserted through holes in the deck. I don't want bare wood exposed to any water that may seep into these bolt holes.
Whenever I penetrate the wood strips I want to seal the exposed grain. With a drill hole, the best way to do this is to drill the hole oversize, fill it with epoxy and then drill the desired hole size through the epoxy plug.
This way the grain of the wood is completely sealed and if someone tries to overtighten the bolts, there is a sleeve of solid epoxy to prevent compression of the wood.
The freshly severed end grain wants to absorb the epoxy. I promote this by heating the epoxy with a heat gun. This lowers the viscosity of the epoxy which allows bubbles to pop and assures the epoxy can soak in as much as it needs to.
I have not yet reinforced the exterior seam where the deck meets the hull. In an effort to keep epoxy drips to a minimum I like to mask off above and below the seam.
By folding in the bottom edge of the masking tape and sticking it to itself, I create a drip edge that forces any drips to fall to the floor before they run down the side of the kayak.
Masking the top is less important, but I find clean up easier it the epoxy layer has a straight edge. I run two strips of tape, one for the fiberglass layer, the next for the fill coat.
In the interest of protecting exposed wood as much as possible, I put a patch of glass into the countersink around the grab loop hole.
I'm reinforcing the outside seam with bias cut strips of the same fiberglass used to cover the deck and hull. To help hold it in place, I pre-wet the surface. I can then stick the strips of cloth to the sides without stretching or distorting them.
After the cloth is wet out, I squeegee off the excess epoxy into a grunge cup.
When the epoxy has set up for a few hours I trim off the excess glass by lightly scoring it inside of the tape with sharp utility knife. Peeling off the green tape pulls the trimmed glass of with it.
I can then apply a fill coat over the seam between the strips of blue tape.
A heat gun pops any bubbles for a clearer finish.
After I think the epoxy has set up enough, I peel off the masking tape.
I was wrong. I didn't wait long enough.
These big ugly drips are annoying, but using a rigid sanding block, or in this case a Shinto Rasp, they aren't that hard to eliminate.
If I were to use a soft block or a power sander with fine grit, I would likely sand through the glass surrounding the drips before knocking them down flat to the surface. An aggressive cutting tool like the rasp just cuts off the high spots, leaving the surrounding surface untouched.
The drips are still annoying, but with the right tool, they don't last long.
The top edge of the seam didn't have the drips, but a quick hit with the rasp smooths the transition.
Now I go over the whole boat with 60 grit on the random orbital sander. I'm using a fairly stiff pad to attack high spots first.
Just like my earlier sanding of the wood, I employ a back-and-forth, followed by up-and-down pattern. The stiff pad does not really conform to the surface, so this pattern assures everywhere on the curved deck gets sanded.
Again, the goal with this sanding session is to knock down high spots. These may include, drips and sags, as well as feathering in edges of added layers of glass. I am planning on another fill coat, so at this stage I interested in starting to level the surface. I want to avoid sanding so deeply that I actually cut into base layer of fiberglass.
After hitting the whole deck with the power sander, I go over it again with a hand sanding block. The goal now is to just de-gloss the remaining epoxy in preparation for another fill coat, so I use a softer pad that conforms to the surface.
Comprehensive sanding includes working on the detail bits such as around the cockpit. I'm still using coarse 60 grit sandpaper.
With the deck complete I flip over to the hull and return to the random orbital sander.
You may have noticed that I never touched the sharp edges with the power sander. I want the feature lines on the deck, at the sheer and at the chine to stay relatively sharp. The power sander would eat right into these, so I come back when I'm all done and take the gloss off by hand sanding.
I also work into the recesses of the deck fittings.
I have found that its not unusual to have tiny pin holes in the epoxy. Surface tension can make it very hard to fill these. What has worked for me is squeegeeing on a thin fill coat, pressing the epoxy into the surface.
While I didn't really thicken this epoxy I did add a small spoon full of colloidal silica to the mix. This doesn't effect the clarity, but adjusts the surface tension enough to keep the resin flat over pin holes.
This thin coat is really just to fill any pin holes. I spread it over the surface, working it into any problems areas and then remove the excess into a grunge cup.
The rest of the deck gets this same treatment, spreading epoxy over the whole surface, being careful not to fill in the deck recesses with drips of resin.
After squeegeeing off the excess, I blast the surface with a little heat to pop any remaining bubbles.
When this layer has tacked up a bit, I want to add a bit thicker fill coat to bury any remaining irregularities.
While thicker than the squeegee coat I just did, I don't need the heavy brushed on fill of earlier coats. I roll on resin to distribute a uniform film, the wet surface is lightly tipped-off with a dry brush to pop most of the bubbles and then flamed with a torch to level and flatten the surface.
Details such as the area around the cockpit are brushed in by hand, being very careful not to leave pools or puddles that will sag or run, making for more sanding work later.
The next day I did the same two-stage fill coat to the hull, first the squeegeed skim coat, followed by a thicker rolled coat.
The quality of your final finish is a function of prep work. Varnish will not fill or smooth a rough surface. A gloss finish highlight any small waves, irregularities or unfair surface with bumps and curves in reflections.
I start the finish sanding with a long board. This somewhat flexible, long sanding block evens out the surface by abrading away the slightly higher spots while bridging over the slightly slower spots until level, fair surface is achieved.
The goal of the long board or fairing sander is to keep sanding away the scratched high spots until they are the same height as the shiny low spots. If you have done a good job of keeping everything fair up to this point, it should take long until you have a uniformly scratched surface with no shiny spots remaining.
Due to the large surface area of the long board, I do need to push a bit to keep it cutting. I strapped the kayak down to the horses to keep it from wandering.
When the hull is done, I flip over the boat and do the same thing to the deck.
The fairing sander is held flat on the boat. I move it forward and back parallel to the strips. Holding it skewed at a bit of an angle helps fair the surface lengthwise as well as across the boat.
Again, I leave the feature line unsanded, working above it and below it in separate operations, never dragging the sander across the sharp line.
With the fairing operation complete I switch back to the random orbital sander.
Going with slightly finer 80 grit sandpaper now, but I'm still using a relatively stiff pad to more aggressively cut down high spots.
Once again, I'm going with my standard, back-and-forth followed by up-and-down sanding pattern to consistently work the whole surface.
I'm still not touching the chine with the power sander.
Flip and continue on the deck.
In spots where the sander does not lay flat on the surface I speed up how fast I move the tool around or throttle down the tool speed to avoid burning through the surface.
The goal now is to eliminate any shiny spots, but without sanding into the fabric. Feathering in the edges of overlapped layers of cloth is OK, but if you are hitting the glass in the middle of a flat surface you may need another fill coat.
When I have completed sanding the whole boat, I add a soft contour adapter pad and switch to finer 120 grit sandpaper.
And sand the whole boat, deck and hull.
Since the surface is now level, the goal of sanding is to eliminate the scratches from the previous courser grit. This goes much more quickly.
After a full pass with the random orbital, I switch to hand sanding with 120 grit to reduce swirl marks. I can now also hit the feature lines, sheer and chine, just sanding enough to remove the gloss.
From there I start working on the detail areas around the cockpit.
I find a soft foam pad works very well for reaching under the coaming and working around the recess.
Cleaning off the sanding dust frequently keeps the paper cutting efficiently and reduces the amount that gets spread around the shop.
I made some sanding tool to help get the hard to reach areas of the coaming.
Upon completion of the 120 grit sanding there is nothing left to do but continue on with 220 grit on a soft pad.
This will be the final sanding prior to varnishing. At this point there should be no shiny spots or dimples left anywhere on the boat. The goal is to eliminate scratches from the coarser paper and creating a silky smooth surface.
Like all the sanding previously, I'm sticking to my systematic left-right, up-down pattern to assure everywhere gets worked evenly.
Even though I'm only sanding out scratches, it still takes some time to be sure the whole surface is in good shape.
The last bit of sanding I do is going of the whole surface with a hand block and 220 grit to reduce sanding swirl. I also hit those detail parts that the power sander won't touch.
Final cleanup starts with a thorough vacuuming to remove as much dust as possible.
The cups of these recessed fittings are a bit tricky. A snippet of sandpaper on the end of a stick does OK at reaching in.
Epoxy is an excellent base for varnish, but through all this work it may have accumulated some contaminants. I first wipe the whole boat down with denatured alcohol. This should clean off any epoxy related residue.
I follow the alcohol with a mineral spirits wipe down. Mineral spirits are compatible with the varnish and should clean off any oily residue which might interfere with the varnish curing.
Step 17: Varnishing, Varnishing, Varnishing ...
As I said in the previous step, a fine finish depends on the prep work. I've sanding the kayak to a smooth and uniform surface with 220 grit sandpaper, now its time to start adding varnish.
The Petrel Play doesn't always have a distinct separation in the shape between the deck and the hull to make an obvious break point for varnishing. I did include a thin accent strip to highlight the transition.
I run a strip of masking tape just below the accent strip. This prevents drips from running down the side. While this will create a tiny ridge along the sheer, it will be camouflaged the accent strip.
Running a strip of masking tape is an underappreciated skill in itself. It takes practice to stretch a smooth, unbroken strip along a curved line. I hold one end stuck in place with my left hand, then pull out a length with my right hand, extending it down along of the feature line. As I press the tape down my left hand, I continue to steer with my right hand to keep the upper edge aligned with the accent strip. I use the stretchiness of the tape to allow it to follow the curved sheer.
Dust is a constant annoyance while varnishing. It is almost impossible to avoid having dust in your paint room if that the same space is also you mill room and sanding station. Diminish how much dust is floating around by keeping activity in your shop to a minimum in the days running up to varnishing.
Immediately before varnishing, wipe down your work surface with a tack cloth. A tack cloth is lint-free cheese cloth treated with a sticky wax material that dust adheres to.
I wipe the cloth over the surface, moving it in one direction so the dust I picked up at the front of the cloth doesn't get spread down again by making it the back of the cloth.
I keep the cloth folded, regularly refolding to expose a fresh, clean section.
One quart of varnish is usually enough to completely finish a kayak with three coats minimum.
I pour out enough for each section into a deep container. Dispensing through a filter will clean out any dust or dried bits that may be in the can.
My system for applying varnish is the same as I described for epoxy fill coats. I work on small sections at a time. The staple holes delimiting one foot sections are a good reference.
After saturating the brush I use heavy, horizontal or lengthwise strokes to get material out of the brush on to the boat.
This wet surface is then evened out with lighter, vertical strokes to smoothly distribute the finish.
Finally, more horizontal strokes with just the tip of the brush pop bubbles and flow out brushing lines.
Then I switch sides and repeat.
By hitting edges such as the stem and grab loop hole first I will brush out any drips created as I proceed.
I'll do two sections on this side before switching back to the other.
Varnish dries very quickly. If you try to extend a section that has already dried a bit you will leave a noticeable bump.
The phrase "Maintaining the wet edge" refers to the task of always extending areas while the previous section is still wet enough for the two sections to blend together smoothly.
This means you need to work fairly quickly and keep switching sides.
Again, the first pass on a section is about getting varnish out of the brush on to the boat. I press hard enough to squeeze the finish out of the foam.
The second pass is about distributing the varnish evenly. Moderate pressure on the brush helps move material from wet spots and apply it to dry spots.
The last pass is really about lifting up excess varnish. A light touch allows the foam to soak up thicker areas as it pops bubbles.
Here is a one foot section done in real time with no cuts. Since I am systematic about it, it takes about 17 seconds to do this section without being rushed.
This means that in about half a minute I am back to the other side where the edge is still wet.
Where I repeat the pattern of horizontal, vertical then horizontal strokes, move over one section and repeat again.
Varnishing is not the time to stop and answer the phone, or go eat a sandwich. The best results happen when you start and keep going until you are done.
When you get to a place where you have a sharp edge like this chine, it is good to think of either side of the edge as separate sections. When I perform my vertical leveling strokes, I do one section then the other to avoid creating drips. If I were to drag my brush across that edge it would scrape additional varnish out of the brush.
As soon as completed this varnishing session, I peel off the masking tape to let the edge relax a little.
Later the same day, the hull coat has dried sufficiently that I can flip the boat over and apply a coat to the deck.
I wipe the boat down with a tack cloth and apply masking tape to the sheer line. I probably should have waited with the tack rag until after taping, but in these early coats it isn't that critical. Think of this as practice.
The trickiest, most time consuming areas to varnish are those with a lot of details and contours like around the cockpit. I address these areas first so I won't lose my wet edges as I move past them later.
I cut down a foam brush to make it easier to reach under the coaming.
Like at the chines, I try to avoid scraping my brush across sharp edges which releases more varnish. Instead I stroke parallel to the edges and come back after to mop up any excess.
Unlike what I'm doing here, it can help to work from the inside out, so you don't end up leaning over sticky wet varnish.
I'm working all the way out to the edge of the recess, so when I pass this way again working on the body of the deck, my transition from wet to dry occurs at the sharp edge so any build up is hard to detect.
Getting finish into these recessed fittings is a bit frustrating. I made a little brush out of the bits I cut of the one for the coaming glued to a stick.
I start by forcing the brush into all the nooks and crannies and then using a lighter touch to soak up the thicker drips.
Once the details are dealt with, it is back to systematically working from one end to the other in one foot sections at a time.
Where I can practically reach over the whole boat, I'll do the whole width at once.
As the boat gets wider, I revert to working on half at a time.
I like a deep container for my varnish because I'm less likely to spill. I will also slap off excess on the inside instead of scraping the brush across the top.
On the final, light lengthwise pass I always stroke from dry towards wet. Landing the brush into a wet area will soak up some material and may leave a mark.
I over brush from one side on to the other to blend the sections together. My final tipping pass extends beyond the newest section into the prior sections.
While working over the fittings, I pay attention to make sure I don't slop a blob into the recess that will result in a sag later.
I often forget about separate parts like the hatch cover. I stick a loop of tape to the bottom to make it easier to hold.
Again I start with the details like these stand-off blocks and the edges before brushing out the body of the part.
Working around the fiddly bits as best I can I first apply the varnish, then level it out, and tip it off.
Even if your first coat looks perfect, one coat of varnish is not enough. It is important to remember why we are varnishing in the first place. Ultra Violet breaks down epoxy. Varnish protects the epoxy from UV.
We need more than one coat to get good protection. For the next coat to stick well we want to rough up the surface of the prior coat. We could sand the surface, but this can remove a lot of the varnish. I like to use abrasive scouring pads like a Scotch-Brite to degloss the surface. It does not remove as much of the protective varnish while giving it good tooth for the next coat.
The scouring leaves some dust which I vacuum off and then follow up with a tack cloth.
Once again, I tape off at the sheerline. I always run the masking tape below the accent strip so I get overlap between the hull and deck coats.
The final appearance of your varnish is primarily a function of how well you do the last coat. This means that a few mistakes in these early coats probably won't mess up the looks of the finished boat, but take these early coats as an opportunity to practice.
My typical work day while varnishing is to degloss everything in the morning, and then varnish the hull immediately. After dinner I come back into the shop and varnish the deck.
The same ritual every time, tack cloth, masking, work on the details, coat the body of the deck, then hit the hatch cover.
The purpose of deglossing is to give the existing varnish some tooth so the next coat will stick well. With these first few coats I am trying to build up some thickness with the varnish. The abrasive scouring pad doesn't really remove much material, and it doesn't level drips or remove dust picks. It just roughens the surface enough so new varnish will stick.
As I add more coats I start thinking more about dust. Here I give the boat a mineral spirits wipe down to remove the deglossing dust.
The number of coats of varnish required is a bit arbitrary, but I would say you want a minimum of three. This should be enough to protect a kayak that gets moderate use for several years. However, more varnish is more protection. And a thick layer can give the finish depth that looks really nice.
But, there are limits. Personally, I start get bored of this sanding and wiping and taping and brushing, peeling, and taping, wiping, and brushing and sanding and wiping and taping and brushing, peeling and
And eventually it all has to stop. But so far, I'm doing OK, I hope you aren't too bored yet.
After three coats, the surface has started to accumulate some bumps and drips. To help level out the finish I'm switching to sandpaper instead of the scouring pad. Sandpaper more aggressively cuts off the high spots to return it to a smooth surface.
With three coats under your belt, you will probably have the drill down pretty well. Being systematic with your process should help you obtain a consistent smooth and glossy film of varnish over the whole kayak.
This will be my final sanding before for the last coat of varnish. I'm wet sanding because it does not gum up the sandpaper quite as quickly and it the water lubricates the surface to help cut faster. It is a bit messy so I don't use water all the time.
Apparently, using a spray bottle of water like this is actually called "damp" sanding instead of wet, but the principle is the same and its easier than having a hose running in my shop.
Like power sanding the epoxy in previous episodes, I'm not touching corners with the hard block. I hold the block flat against the large surfaces so I don't burn through the varnish. The fine corners will be touched up later.
The water beads up when it first hits the varnish. As the surface gets scratched up the beads disappear.
Wipe off the sanding sludge as you go so you can inspect your work. The gunk can be really quite tenacious if you let it dry, so try to keep after it.
If you see any shiny spots, spray on more water and resand the area.
When the boat is all sanded out, I wipe it down with water.
After the water has evaporated, I go over it again with mineral spirits to assure there is no residual moisture.
This time I use a polypropylene fine line masking tape which is thinner than standard tape and leaves less of a ridge at the edge.
The camera stopped while I was finishing the hull, but you are getting bored and don't want to watch that anyway.
So, I'll make you watch the deck. The process is the same systematic, left-right, up-down, left right, move to the next section work you've been watching for the last 15 minutes. After 5 coats you should be pretty good at it.
Step 18: Fitting Out
There is a tube running from the skeg control slot beside the cockpit to the skeg box near the stern. The skeg is operated via a cable running through that tube.
I slide the cable in from the control slot back to the box. I then secure the skeg fin to the cable with a set screw.
The skeg fin is hooked on to the pivot pin inside the skeg box.
I slip the control knob on to the cable and then feed the cable into the control tube.
There is a small hole in the side of the control tube to accept the set screw in the knob. I start tightening the set screw until I feel it engage in the hole.
Before I tighten the set screw completely, I slide the knob all the way forward and then move the fin to the fully retracted position. With both the knob and the fin in the same position I can tighten the set screw.
The system is a little stiff the first few times but it loosens up with use.
I had placed some masking film inside the cockpit to protect against varnish drips. Its time it came out.
I like to make my bulkheads out of 3" minicel foam. It is lightweight, resilient and doesn't need to be cut perfectly to fit snuggly.
It just gets wrestled in place.
After cutting out the bulkhead, I took a little time to round over the corners a bit. This creates a groove around the perimeter which I will fill with caulk.
Caulk can be messy stuff, so I find it useful to run masking tape beside the foam.
Masking film extends the protected area because 3M 5200 caulk is really messy.
I carefully squeeze a bead into the seam between the bulkhead and kayak. I highly recommend wearing gloves because this stuff is super messy.
A finger is the best tool to press the extremely messy caulk into the seam. If you make a mess, which you will, denatured alcohol will clean it off.
Peel the masking film and tape off before the caulk cures. Be careful not to make a mess.
I drill a couple holes up under the coaming lip for bolts to hold nylon cable clamp loops for back band support.
The back band is secured to the cheek plates with bolts threaded into T-nuts. The stainless steel t-nuts a secured in place with some epoxy.
The bolts I use are flat headed and they lie fairly flush into finish washers.
After securing the back band on both sides I run shock cords up through the loops at the back to hold the back band in place.
A water knot is an interlaced overhand knot that is very good for hold shock cord.
I use the same water knot for grab loops. I form an over hand knot in one end, and then retrace that knot backwards with the other end.
Pulled tight it makes a comfortable ball to grab.
These deck lines will just be shock cord. The cord is threaded through the recessed fittings in a cross pattern.
A length of heat shrink tubing will protect and hide the joining of the cord ends.
I could use another water knot here, but I like the clean look of a couple stainless steel hog rings hidden in the heat shrink.
Hog rings are stiff wire that is squeezed tight around the cord. This creates a very secure joint. I use two just to be sure.
The ends are then trimmed off and the heat shrink is slid over the connection before using a heat gun to shrink the tubing down.
The seat will be secured in place with contact cement. You only have one shot with contact cement so you need to be sure you know exactly where you're putting the seat.
Spread the glue evenly on the bottom of the boat. Here I'm using a chip brush, but a foam one may be used instead. The brush will be trash when you're done.
More glue goes on the bottom of the seat in a smooth uniform layer.
After the glue has been applied to both mating surfaces, it needs to sit for a while until it is dry to the touch.
The two glued surfaces will grab the moment they contact each other, so be sure to align everything perfectly before pushing the seat down in place.
Press down to assure there is good contact everywhere.
The hatch cover is secured with nylon straps that are bolted to the deck through the holes drilled earlier.
Self-adhesive closed cell weather stripping makes an effective gasket to keep water out of the compartment.
I cut a ramp at the starting end with a sharp brand-new razor blade.
The weather stripping is pressed in place all the way around the perimeter of the hatch.
At the finish end, I run the strip up the ramp cut earlier. Trimming this off flush like a scarf creates an unbroken gasket.
A length of parachute cord tied to the hatch and a loop inside prevents the cover from accidentally floating away.
These side release buckles create a tight secure closure. And that closes the build phase of this project.
Step 19: Launching!
No boat of any kind is truly complete until it has been put in the water. Before that it's just a boat-like object. While I built this kayak for a customer, I did have a chance to get it out on the water a couple times before delivery. This video is a compilation of those two trips.
I'll keep quiet while I take you out the Poquonnock River, onto Fishers Island Sound, to a tide race we call "The Cans" and then back home again.
This kayak is fun.
I am really pleased with how the boat came out. At 31 pounds or about 14 kilograms the light weight is easy to carry down to the shore. On the water its sprightly and responsive. On flatwater the kayak was comfortable and easy to paddle. In rougher conditions, it accelerated quickly, surfed smoothly and worked upwind easily.
I was happy and so was the customer.
As I finish off this series, I hope I've inspired some of you to take on a boatbuilding project. Maybe its less intimidating now that you have seen it all done. I enjoy every aspect, from choosing a design, through making the kayak and finally getting out on the water in a beautiful vessel that I made myself.