serene – 3, part 6

Next is jointing the plywood pieces: 8 joints for the hull, and just 1 for the deck, to form the bilges that would build up into the boat shape. For the 2 pairs of hull’s bilges, I flip one pair by 180 degree when drawing on the boards, so that to distribute the joints at different places across the boat length, and not to concentrate too much joints into one proximity. That old boatbuilding carpenter’s trick is not completely necessary with modern building techniques, but it’s nice to do so anyway.

The tried – and – true technique of straight finger joint is used as always. The straight joints are easy to cut, and most importantly much easier to be aligned following a straight line for all the jointing parts, so that to make sure all the bilges would be jointed into the correct shapes. All the joints are treated carefully, first is applying a layer of thinned epoxy (using xylene as a solvent, for the substance to penetrate deeply into the plywood), then gluing with epoxy, then a layer of glass on the internal side.

I beveled the edges of the deck parts a bit (at 45 degrees), so that they would fit tightly and nicely together forming straight seam lines. But that’s not applied to the hull, where the cursive seam lines don’t like very thin edges. Experiences from my previous boats showed that, it’s best just to use the squared edges, the thin edges doesn’t stay on each other very well, and would deform, distort the seam lines! You would later just apply thickened epoxy on both sides (in and out) of the seams!

serene – 3, part 5

The progress is really slow lately, several weeks passed, but little get done! Things started moving anyhow, I “quickly” transfer the “offset tables” onto the plywood boards, draw all the bilges, bulkheads, and other parts. The greatest thing of all is that now I’ve purchased very good sheets of plywood, not truly marine – grade (there’s no such in Vietnam), but high – grade water – resistance ones. I could feel it when do the sawing, the boards are quit tough, not fragile as with my previous ply!

There would be an immediate consequence with the new plywood, I would just use less epoxy to pre – fill the boards, and since the boards is stiffer, the glassing would be done on the outside only, that would significantly save the boat weight, I hope. All drawing is completed quickly, I finished in just less than one day, next come the steps of cutting and jointing the bilges. Everything has been done many times before already, so I didn’t have to think or consider things much, just repeat it!

4th image: the cockpit coaming frame cut from a piece of 18 mm MDF. This cockpit is drawn using the mathematic formula mentioned in my last post. It came very closed to the shape of Serene – 2‘s cockpit, but slightly smaller on each sides by about 5 mm, so my existing spray skirt should fit tightly with this new coaming (on Serene – 2, it’s too tight). The coaming would be constructed from 2 layers of 4 mm plywood, and I would later omit out the (a bit tricky) glass reinforcement on this part!

how to draw a kayak cockpit mathematically?

Over the years of designing and building wooden kayak, often a recurring question comes to my mind: how can we precisely construct a kayak cockpit shape in a mathematical way. Today, I spent 30 minutes to figure out the problem, it turned out to be quite easy indeed. But first of all, there are so many different shapes for cockpits, and everyone may have his / her own preference on how it should look like. Here I try to plot a shape that is most suited to my eyes, and closed to what’s usually called “an ocean cockpit” found on Greenland kayaks.

I went to the Wolfram Alpha website (wolframalpha.com) and entered an ellipse function. Apparently a cockpit shape is not elliptic, but rather an asymmetric “egg shape”. I tweaked around the equation for a while, changing its components, and the shape came out, closely resembles that of my Serene – 2. I’d also tried to construct other types of “egg shapes”, for example, an 3 – ellipse that has 3 foci, something that could be drawn with closed thread of rope running around 3 nails pinned on a wooden board (similar to drawing an 2 – ellipse with 2 foci).

But it’s hard to determine the dimensions of that 3 – ellipse, and the positions of its 3 foci. Finally, I found out the formula that is best suited for me, something that could be determined numerically to ease out the actual drawing. The formula finally: x2 + 3.5y2 + 1.5xy2 = 1. Upon close inspection, the “egg shape” turned out to be very satisfactory. One might try changing just the “weight” parameters (e.g: 3.5, 1.5…) and retaining degrees of the polynomial’s terms, to experiment with different other shapes, to figure out what is best according to one’s need.

Next come the question of how to draw this shape onto the wooden board that would actually construct the cockpit coaming? A bit of thinking has the problem solved too. The Wolfram Alpha website provides us with numerical formulas. The general steps are like this:

1. Draw a bounding box in the dimensions you want, mine is: 39×72 (cm), the dimension that your spray skirt would fit into (and the spray skirt vendor usually supply you with this information before – hand). The x value would have the value range of [-1, 1].

2. Draw a dense grid of x & y inside that bounding box, for each value of x from -1 to 1, calculate the y value with the formulas given above. Giving very fine incremental values of x, say every 1 or 2 cm, it would be possible to construct a good looking “egg shape” then.

Of course, I want to find out a way to draw the “egg shape” more precisely and more conveniently, e.g: print the plotting actual size on paper, but found it a bit cumbersome as I have no printer of that size! Anyone finding out a good way, please kindly let me know!

serene – 3, part 4

Finally, I managed to have some time slots to start the kayak building. Works would be carried out mostly at weekends, and hopefully, the boat could be finished within this year. After much hesitations, procrastinations, and considerations into the very details, I’ve incorporated quite some “innovations” into the final design, as well as some “simplifications” to ease the building process. I “hope” this is also my “last” stitch – and – glue boat, the 6th of “the fleet”, seems to be a lot already!

The past 2, 3 weeks were spent mostly on reviewing, fine – tuning the design, “rehearse” the overall building techniques and process. This is a design that consumes my brainstorm the most! Many building steps could be done very quick now, as they have been done 5, 6 times already. So I would skip documenting in various parts, as they are all similar as in my previous boats, only to highlight things that are different. First is setting up the molding stations, cut from MDF as usual.

There would be 9 molding stations (female type) for the hull, and only 4 stations for the deck, each positioned 0.6m apart. One of my last changes to the deck was modifying its sides’ “slope” to 45 degrees, the deck would have lots of “flare” in the inverted position, that’s to make rolling easier. Once the boat is up – side – down and the deck becomes the bottom, so a “stable” full – shape deck wouldn’t be good for practicing kayak rolling. And I guess it could give some help to the boat’s windage too.

serene – 3, part 3

There’re so many minor improves here and there, and lots of design considerations too, to maximize the usability of the kayak under various real – world conditions. The aft deck is lowered a bit, to facilitate climbing in the cockpit once thrown own by a complete capsize. There’re two deep – water reentry techniques that I was considering possible with this boat design. Wet – reentry has been a shortcoming of previous designs, being too slim and unstable to make an easy access.

This is not a kayak specially tailored for rolling, but Serene – 3 is designed with concerns of balance – brace and rollings in mind. At the moment, I’m not too sure about its capability to roll under full load and heavy sea conditions, but I’m quite confident for its easy recovering in brace actions. Also, the hatches’ design has been reviewed and modified, to improve their water – tight capability, I’m putting great hope in the new gaskets which would be made by silicone molding to accommodate the hatches.

Also, there would be 3 hatches, all big (no small day hatch) to better utilize the internal containing volume. The rudder design is also reviewed and altered, I need lighter pedaling, and quicker overall responsiveness for the rudder actions, a new type of rudder post, new layout for control cabling too. The electronic system would received a bunch of improves in building techniques, decoupling the whole system into several separable components, to make maintenance and repair easier later on.

serene – 3, part 2

Also, the deck height right after the cockpit is reduced, so that climbing in the kayak would be easier. The hull’s upper bilges now have much more flare, especially at the 2 ends, to help improving secondary stability, that also has Cp (prismatic coefficient) increased to about 0.52 ~ 0.53, a value usually seen on a faster cruising kayak, unlike the quite – low value of 0.5 on my previous Serene – 2. Transverse metacentric height – Kmt increased to 26 ~ 27 cm, which indicates satisfactory initial stability.

Thus, Serene – 3 is designed with a shift to (primary and secondary) stability concerns. Directional stability (reflected by the Cb – block coefficient value of 0.39) is ensured with an improved rudder system. The beam is slightly widen to 46 cm, and LOA stays at 17 feet. The 5.2m length is an important factor, cause it could entirely fit into a 4 meter truck, which could be easily hired to transport the boat if needed, otherwise at 18 feet, I would need a larger truck, which could be hard to find.

The hull features a deeper V – bottom, something similar to that of the Illorsuit. In all three Serene – 1, 2, 3 designs, I’ve always tried to combine deep V – hull with a narrow beam, something until now I’ve only partially succeeded. Various other improves would be incorporated into this boat. I would build different hatches with big silicone gaskets, to completely solve the water leaking problem (hopefully). Also, there would be 3 hatches along the kayak, to better utilized the storage volume inside.

serene – 3, part 1

It’s time to move on to a new kayak design. Lessons learnt from my last failed trip signifies the necessity for a boat design that is geared toward a wide range of self – rescue actions such as: balanced brace, roll and wet – entry. Thanks to the very dynamic world – wide sea – kayak community, which constantly invents and improves various techniques, I’ve updated myself to some newer self – rescue techniques which I consider to be critically important for long cruising trips.

My previous boat, Serene – 2 has some obvious shortcomings though: initial stability is still slightly problematic, especially for reentry; the electricity system, though working very well, is hard to repair or upgrade, this is due to my inexperience with electrical wiring. I would incorporate into this kayak design various small improves here and there: the storage compartments and hatches would be rearranged to better utilize the boat’s volume, a new rudder system with better responsiveness, etc…

For the last 2 months, most of my free times is directed toward working with FreeShip, the very helpful boat – designing software. Some design parameters: LOA: 5.2m (17′), Beam: 46 cm, Displacement: 120 kg, Cp (prismatic coefficient): 5.3, S (wetted surface): 1.95, Cb (block coefficient): 0.39, Cw (waterplane coefficient): 0.7… The most important change compared to Serene – 2 is a significant increase in rocker, the boat is now much curvy, having the mid section deeper seated in water.

hard vs soft chines

Vẫn đang loay hoay suy nghĩ về thiết kế kayak, hard-chine hay là soft-chine, những đường cong mềm mại, hay những cạnh vát sắc nét, mỗi cái đều có ưu, nhược riêng. Dù anh có đi theo hướng nào, thì vẫn luôn có người làm ngược lại, đó đơn giản là sự đa dạng của suy nghĩ con người. Trong một thế giới lành mạnh, sự khác biệt đúng ra là để hỗ trợ, bổ sung cho nhau, thay vì kình chống nhau…

serene – 2, part 42

Made some more longer paddlings (20 ~ 25 km) to get to really know her, my newly – built Serene – 2. It’s not until now that I could get myself familiarized with the boat’s primary stability, which could be really “frightening” to most novice paddlers. In reality, Serene – 2 is “more stable” compared to Serene – 1, but with a much higher free board, the secondary stability comes a bit later, to assure that everything is alright!

Actually, I’m a bit concerned about the boat’s primary stability, cause it has lots of V – bottom the under side. I would need to trail the kayak in its full capacity, to really make sure that the boat reaches its expected stability when fully – loaded with gears for a multiple – days paddling trip. The “fearful, uneasy feeling” caused by the low primary stability should not be taken for granted at all, even when I know that it’s safe.

Cause you would virtually going nowhere when all the time, you’re just worrying about it, worrying that something (a potential capsize) would happen. I’m pretty sure that the boat would be fine at its designed displacement, but only trialling would tell precisely. Looking back at all my boat building, boat playing times, lots of fearful moments, lots of self – doubting, self – disappointments, self – blaming, etc…

But that’s the nature of boating things, of “adventures” on the water. It requires lots of practicing and improving, to make sure that everything is right, that everything just works. My paddling performance is really really bad lately, with very little training ever since my last 9 days paddling trip in June. Obviously, something need to be improved here, and that would be among my resolutions in the coming new year!

serene – 2, part 41

Made several longer paddlings (15 ~ 20 km) to see how the kayak would perform. As with all my previous boats, it takes some little time for me to adapt myself to a new boat, in particular, the primary stability. Each kayak differs by a little, after a few dozens of kilometers, I would feel more comfortable and confident with the boat’s motions. Only after that, the speed measures could be evaluated more accurately.

The Garmin GPS data shows that I could sustain about 7 kmph with my new kayak. That’s pretty much very good, though only slightly better compared to Serene – 1 (it was about 6.5+ kmph). The 7 kmph value is very closed to the average speed that other famous sea kayakers would usually make. The improvement at this point is very critical, since I can hardly make any more gain without sacrifices to the boat stability.

The weather this season is quite ideal for paddling, the temperature is dropping to around 20 ~ 25 degree (Celsius). The Northern wind is blowing, but much a lesser amplitude compared to this time last year. But too bad, I’m quite busy with my works and can’t spend much time on water, my paddling performance is not truly at its peak, so it’s still early to say more about the new kayak’s performance characteristics.

Anyway, I’m feeling very pleased with my new kayak, and I think that with more training, I could bring her to a much better performance level. Some more works required still on the kayak though, in essence, I would have to rework the USB – charging circuit, the current one is over – powered by the 3 powerful Lithium cells and wouldn’t work very well. Christmas and New Year season is coming, happy season to everyone!

serene – 2, part 40

Continue trialling and adjusting various boat equipments. The 2.2 Amph SLA battery works, but not to my expectation, first, it’s too heavy, second, its capacity is quite small, and third, the battery doesn’t hold its electricity for too long, about 2 days without charging and the battery would exhaust… After consulting with some other paddlers, I’ve decided to replace it with 3 Lithium cells, the results are just… superb!

I now have about 10 Amph in the very small 3 Li-ion cells, almost 5 times more the capacity, and 5 times less the weight, yet 5 times the price, advancements in battery technologies is just amazing! According to one of my friend, an “expert” in electric and electronic devices, the Li-ion would usually last longer, and compared to the SLA, with zero maintenance cost. After replacing the battery, I fitted the last electrical components.

The AA charger and the USB charger, they’re positioned inside another waterproof box, connected to the battery box with electrical wires inside a plastic tube. The installation is pretty easy, the two devices are connected via two switches, simply put your iPhone (or your VHF radio, or your AA batteries) into the box, turn on the switch, close the box, and let the Li-ion cells, plus the solar panel do their job!

Also, I’ve removed the plastic seat, replace it with just a back – rest instead. The back – rest is built from plywood, bent into a curved shape, covered on 1 side with a rubber sheet (to make your back resting more comfortable), and fitted into the cockpit aft, it could be rotated slightly to suit my various sitting positions. These are last updates for the boat in this 2016 year, now it’s time to just enjoy the water!

serene – 2, part 39

Made several short paddlings (10, 12 km) to trial my newly – built Serene – 2 kayak. The overall feeling is very pleasing, the boat is much easier to control compared to my previous one Serene – 1, and it’s faster, taking up momentum in just a few light strokes! But the velocity measures would be postponed until I could finish all equippings, all adjustments, and begin longer paddling to know precisely.

Yesterday, I had a capsize in my kayak, reason is that the seat raises the center of gravity (CG) by approximately 5 cm, just a very short distance but severely affect the boat stability. This is something I’d already knew in the designing phase, but still try to do the silly thing of installing the inappropriate seat. The solution is quite simple: remove the seat, just sit barely on the bottom, and build just a back – rest instead.

Apart from that, everything works well enough: the bilge pump, the rudder and rudder pedals, other electrical devices, etc… The shorter hull reacts more sensitively to load balancing, the kayak needs to be trimmed a little bit further aft to reach its most stable point. I’m especially happy with the rudder, to give a decisive conclusion on the Rudder vs. Skeg debate: the Skeg is simply left too far behind to argue!

Only long paddling would tell, if there’re some significant improves in “economical speed”, the important point of a kayak designed for cruising: the minimum effort required to propel the boat on large distance and in prolonged period of time. It takes some more efforts and times to really complete harnessing my Andalusian horse and make it ready for sea paddling trips in this Northern monsoon wind season!

serene – 2, part 38

Many miscellaneous jobs required still to finish equipping my new kayak for upcoming paddling trips. First is adjusting the seat’s back rest, it’s a bit too high that strapping on the spray skirt could be a bit difficult. I simple cut down its back, then rivet the cut – out part onto the rest part. The hatches’ gaskets are cut from a thin (5 mm) rubber sheet (1st & 2nd images), should do their job of keeping the water out.

I made a new cart for transporting the boat on land, it’s just a smaller and lighter version of the previous one. I reused the pair of wheel, couldn’t reduce the wheels’ size since they have to be big enough so that the cart wouldn’t sink in when pulled on sand and mud. The result is quite satisfactory, big enough to easily transport the kayak, and small enough to not affect the boat stability when carried on the aft deck.

The list of small jobs to really finish the boat seems to be never ending, there’s always something I could do to improve, here and there, e.g: a mesh bag would be installed inside the cockpit, under the deck, to store various things I could need during a paddling trip, e.g: a small knife, a tiny light torch, a small monocular (to be equipped), reserved batteries for camera and GoPro, lighter, my tobacco box, etc…

It’s an interesting experience equipping a kayak for long paddling trips: everything need to be ready and accessible around your cockpit: food and drink, the back up paddle, the paddle float, radio and camera, everything… Fortunately, my newly purchased PFD has two pockets on the front side where I could hold some crucial things with me: the VHF radio, the Garmin and the Cannon waterproof small camera!

serene – 2, part 37

Continue trialling my newly – built kayak with some short paddlings. The adjusted rudder pedals now work properly and smoothly. The battery system charged well, everything works as expected. One point I’ve found out is that, the SLA (Sealed Lead Acid) battery should be positioned upright for it to be charged to its maximum capacity. I was thinking about Lithium battery which is more compact, lighter, has more capacity…

But that would be later, maybe I should deploy a system of SLA and Lithium in parallel, as the SLA could provide short – bursts of hight current (required by the bilge pump), and the Lithium could provide a lower amperage for a longer period of time. Today, the Sea – to – summit spray skirt package arrived, the all – neoprene thick skirt fits well to the cockpit coaming, it should do its job of keeping the water out well!

Also I’ve found out that I need to adjust the seat’s back rest a bit, it’s too high that strapping the skirt on could be a bit difficult. One important add-on to the kayak is the water drinking system. 2nd image: the 2 plastic water bags, from left to right: 10 and 8 liters respectively. The smaller oval – shaped water bag is put in the forward compartment, with a water tube running through a cable gland over the deck.

That way you can drink (suck the water out of the reservoir through the tube) without having to stop paddling. The low – lying bags would help with the boat’s stability, no more bulky water bottles needed, and the deck space would be clearer for other items of necessity. I’ve found this drinking system idea very practical, as I’ve lost quite some water bottles lashed to the bungee cords in heavy sea, when strong waves wash over the deck.

serene – 2, part 36

Made the first trialling of my kayak today, a short 10 km paddling just to verify if everything works! All goes smoothly, hurray! The solar panel is adding juice to the battery, could see that obviously since the lights have become more intense, and pump has become much stronger (I almost used up the battery the day before). Under this tropical sun, that wouldn’t be a hard task for the solar cells, I guess!

The rudder works nicely, the pedals could be easily kicked by my legs, changing direction instantly. The pedals movements could be improved however, to become lighter and more responsive. Every parts of the boat simply just work! And the paddles also, I’m feeling pleased with the new paddles. And for the main part, the boat itself… it feel just a bit more stable (that’s what I was expecting for), but the hull now tracks much better!

It could go quite straight even without the rudder deployed. The feeling that the shorter boat is very steady, and could possibly go faster compared to my previous Serene – 1 kayak. Though the LOA (length over all) of Serene – 2 is shorter, its LWL (length waterline) is pretty much the same. The higher free board makes climbing into the boat a bit more difficult, but that’s not a problem, cause the cockpit now is a bit larger.

The slightly higher free board is very important, it should keep water out of the deck for many of the times, and hence waves shouldn’t threaten flooding the hatches much. My overall feeling is very pleasing, for those months of efforts put into the watercraft! But 10 km is too short, I need to trial the new kayak more, and record the routes by my Garmin, to really evaluate the boat’s performances in precise numbers.

serene – 2, part 35

Sticking the vinyl decal decorations is among the last steps that complete the kayak. Since the deck spaces are almost used up for various accessories, the boat names and owner’s informations go onto the port and starboard sides instead, and the boat eyes intrinsic for any Vietnamese boat of course! The solar panel is tied on the aft deck, stretched with two short wooden spars, and lines through its grommets.

There’re some more items to be built or fitted for this kayak: the seat, the carriage for transporting the boat. I would rebuild my previous carriage, reuse the 2 wheels, but build it lighter and smaller, to easier carry it on the aft deck. The seat and back rest are also important parts, but those would be postponed to a later phase of the project. Also, I’m still waiting for my spray skirt to be shipped from Amazon.

After sticking the vinyl decal decorations, the bottom receives additional 2 layers of transparent PU paint, making them 3 layers in total for the bottom (the deck only received 2 layers), protecting the vinyls. The handle line pulling through a hole drilled at the bow (with a wooden block inside) is just a simple hang – man knot, the kayak has no handle at the stern, since the rudder has taken up all the space.

It’s so good a feeling to see the boat completed! Looking back on the building progress, there’re still things that I’m not really pleased with, in building quality, in the look & feel, in equipments… But I believe this is my best boat so far, accommodating various small design changes that I’ve found neccessary from my paddling experiences. I should start trialling the kayak soon, to see how she would behave on water!

serene – 2, part 34

The bilge pump is a critical component of this Serene – 2 kayak. Empty out a flooded boat, or simply make your seat less wet, it gives you lots of confidence and convenience on long paddling trips. Today, I installed the bilge pump with its water hose (through a hole drilled on the port side). Electrical wires are connected and carefully sealed inside plastic tubes with silicone glue to make them really waterproof.

I wouldn’t want the whole system to collapse just because of one leaked electrical wire (anyhow, there’s still the fuse in case of a power surge, e.g: short circuit somewhere). Watch the short video below to see how the bilge pump works, it’s just so great! I would just move a wooden knob (the reed switch), and the water jumps out! The small “buzz, buzz” vibrating sound of the bilge pump is so fascinating!

One problem, however, due to the very deep V – bottom of the kayak, some small amount of water remains still at the bottom which could not be sucked out by the pump. That’s not a big problem anyhow, cause I would install a seat that raises me a few centimeters higher on the floor, and wouldn’t make my pant soaking wet. In the video, the water flow doesn’t look very strong, since the battery is already running low.

I would make more thorough testings to see how the whole system works in combination: battery, solar panel, lights, and bilge pump! But I would wait until the 12V battery “fuel gauge” shipped from Amazon, so that I can have exact measures on the battery usage, how many times it could pump out a boatful of water. It’s important to understand how your system works, so that you could make good uses of them on longer journeys!

serene – 2, part 33

Rectified one problem with the signal light, the bulb is too greedy, it eats up a lot of electricity and could potentially burn up the reed switch (I’ve noticed the reed switch has malfunctioned sometimes due to the high current). So I replace the bulb with 8 small white LEDs (1 Watt each). Some more soldering work, but finally it’s done, equally bright, but less power consumed, and safer for the switch.

Today, I installed and tested the rudder system. First is the two cable lines used to pull the rudder up and down. The 2 lines run back to the cockpit and are attached to 2 small wooden balls, with a short segment of bungee cord. Third image: the wooden balls and bungee cord. The bungee serves as a shock cord, in case the rudder should collide with some thing and kicked back, so that no damage would be done to the whole system.

One simple rule to operate the pull up / down lines: grab the ball that is further from the cockpit and pull it. Well, it sounds pretty simple, but useful enough, when in action, you just don’t have to think over and over again: which line is up, and which line is down! The two rudder control lines run back to inside the cockpit where they’re attached to the pedals via 2 small wooden jam cleats to adjust the lines’ tension.

All works well, but the pedal motions are not really smooth, because the bungee cords are not strong enough to pull the pedals back (once one pedal is kicked, I would just have to kick the other pedal to balance the rudder). But I would just leave them as they are for now, as they’re working already, would consider replacing the bungees with stronger ones (or revise the design a bit) later on.

serene – 2, part 32

The hull is painted with 2 layers of transparent PU paint. In this tropical weather, paint dries so fast, after about 3 or 4 hours, I can start the various deck fittings: mounting the forward hatch with compass on top (and compass light). The electric wires (housing inside a plastic tube) supplying power to the compass light also serves as a holding line, just in the rare case that the hatch could fall out.

The signal light is done the same way, connect the electric wires, seal them inside tube with silicone glue, test if the reed switch work. Until now, all 3 reed switches works well, I shouldn’t worry much about them, as reed switches, though tiny in size (less than 3 mm in diameter), are in fact very durable (rated at 100 000 times of turning on / off). In the silent night, I can hear the click, click sound of them turning on / off.

Fitting the bungee cords is quite straight forward. The anchor points (made from wood) work well enough, I just pull a thread through easily, don’t have to “prime” with a small steel wire like before. The forward bungee cords also run through 2 wooden blocks (see the third image), each house a magnet inside. I use the NdFeB (rare earth) magnets, which are really strong, they could turn on the reed switch 2 or 3 cm away.

Next, I would fit the rudder pedals, run the rudder control lines and see how all things works. Then comes the bilge pump, with the water hose, then the solar panel. The ugly thing is that you just don’t know how much power left in your battery, or if the solar panel is doing its job. So I ordered a “12V battery fuel gauge” from Amazon to read out the current capacity of my SLA battery. Below: a short video to show how the reed switches work!

serene – 2, part 31

After joining the hull and deck, the hull receives its final bottom glassing. The fiber fabric would overlap the deck about an inch, to better seal the joint. One little trick to make a clean, tidy line at the painting (or epoxy) boundary: mask the area to paint (or to fill with epoxy) with duct tape. Prior to applying (colored) paint or epoxy, brush the duct tape with a very thin layer of transparent paint (or epoxy).

Wait for the paint (or epoxy) to cure, than apply the (colored) paint (or epoxy). That way, the colored paint (or epoxy) won’t leak through the duct tape, cause no matter how good the duct tape is, paint (or epoxy) would leak through, causing a blurry, untidy line. Second image: masking with duct tape, prepare for glassing the hull. I run out of my fiberglass fabric roll after this task, also use up the last drop of epoxy!

The hull glassing receives an additional layer of fill coat, then another layer of epoxy at the 3 seams, then a slight sanding. I don’t sand much, just at some rough places. The color scheme for this kayak is also brown / yellow like my previous two boats, but this time, the colors would be much lighter. Next would goes in the vinyl decal decorations, then varnishing the whole hull and deck with transparent PU paint.

Since the deck’s space is used up for the 3 hatches, the bungee cords, the signal light and solar panel, and other accessories, all decorations would go to port and starboard sides: the boat eyes, boat name, and owner’s information! There’re many many other unnamed tasks required still to finish the boat, so I won’t hope to complete it until next week. However, the kayak would see water and start its trial paddling very soon!