etween the trials, I managed to complete a couple of things. First is to mount the compass, the tried – and – true type of compass used in all boats of the Serene series, this without an internal lighting. Then, I built another paddle, a simple one with rattan shaft, and plywood blades, a little bit bigger, weights at 1.1 kg, slightly heavier than the Greenland companion – my “storm paddle”, 0.9 kg. Still considered an Euro – type paddle, but with a smaller blade to resemble Greenland style.

As I sometimes need larger power faces to propel the boat under unfavorable conditions. The rudder control lines are modified to be more easily adjustable, see the second image below. The pedals are attached to small segment of chains, to adjust the tension, you simple move the shackle to another chains’ eye, this could be quickly done while you’re in the field. I also replaced the bungee cords holding the pedals back by 2 large steel springs, providing better “suspension”.

Just release one pedal and the springs would pull the rudder blade back to its neutral position. I added 4 tiny 3.7V LED bulbs (series wiring) to the electric box, in an attempt to indicate the batteries’ remaining capacity (as there’s no easy way to do so). This is a trick I learnt from experiences, when 1 or 2 of the LED bulbs won’t turn on, or their brightness is drastically reduced, you’d need to plug in the solar panel then! 😀 Not all works has been completed, but it’s time to clean up the workshop a bit!

aunch the boat today, first day of the year 2018 😀! Took the kayak out to water on a sunny, breezy afternoon for a 12 km paddling, the temperature was around 25 ~ 27 Celsius, considered “cool” with this hot – all – around – the – year tropical climate. The short paddling is just to get some first impressions, to check if everything works, and how it feels, the new hull shape, something radically different from my previous boats. Yet all confirms things I’d known from the design phase.

The kayak is nimble and very predictable, probably not too agile compared to Serene – 1 and Serene – 2, it’s also a bit more stable across all its axis. It’s easier to get in and out of the cockpit with these stabilities. The rudder works nicely, changing course instantly with just some slight pedal kicks, though I’ve come up with some new ideas to improve the “fine – tuning mechanism” for the rudder control lines’ tension (the cleats used are fine, but not too convenient for adjusting the tension).

The rudder pedals offer very good seating position, together with the plastic seat (used for testing), fixing my lower body well to the hull. I would decide later whether to just use this plastic seat, or build another lower one to facilitate reentry actions. The hatches are absolutely water tight, an important criterion! The overall feeling is very satisfactory, yet more trials are needed, in different conditions, especially on rougher water, to really understand the capabilities of this new boat.

lmost ready for the water, but the tide is unfavorable for the weekend (its heights are at night), and the Tembin cyclone is crossing the East sea, threatening the area. So I take the time to complete a couple more things. Attaching the electric box through cable gland is quite straight forward, everything works out right, in essence the bilge pump and reed switch. I added one master switch to the electric circuit, in order to turn everything off and not to drain the 18650 batteries to exhaustion.

One critically important issue with the 18650 batteries is that, never used them to exhaustion, when the voltage drops below 1 ~ 1.5 V or so, the battery just becomes dead, you simple could just throw them away, a costly lesson the last time I hadn’t paddled for some weeks, and let the batteries run until dead 😢. Next, I “refurbish” one of my old paddles to match the new boat style, turning it to black, and make it a bit stronger (and slightly heavier) with an extra layer of fiberglass.

The paddle was specially built from rattan and balsa wood, and is light enough already at 0.8 kg. I would try to use this paddle first, before deciding if it’s necessary to make an extra new one, weight and durability are two major concerns. Third image: a “smoke test” to verify if the bilge pump and the solar panel all properly works. Now wait out for a few more days before going to water, just some 10 ~ 12 km of paddling, to see how the kayak behaves, how everything would feel out there.

askets fabrication: the critical thing in a hatch’s waterproofness is its gasket, and I realized that the best material for gasket is silicone: flexible, durable and offer a very good fit. And for a custom size and shape hatch, somehow I’ll need to make the gaskets too. It turned out to be pretty much easy, using the 2 – parts silicone available here on local market. You mix up component A to component B (catalyst, around 1 ~ 4 % by weight) and pour it into a mold, wait for about 2 hours, and it’s done.

1^st image: the mold (cut from plywood) is filled with silicone, I use the “Silicone” (red bottle) spray as a mold release, it’s “strange” that silicone is used as a release agent also for silicone. 2^nd image: the product, the O – ring released from the mold. 3^rd image: the gaskets inside the hatch lids. The gaskets are 15 mm wide, 5 mm thick, and are pressed down to the hatch rings with those belt locks. I hope I would end up with excellent waterproofness, but let wait until “sea trial” to know better.

I reuse the bilge pump from my previous boat, it still sees very little use, the installation is quite straight forward using some cable ties fastening the bilge pump into its mount. The flexible water pipe leads to a hose right on the right side behind the cockpit, the hose is protected by a screw – in cap, to prevent water from leaking back into the boat when waves wash over the low aft deck. The bilge pump really offers lots of convenience and confidence when you are out there, in the roughness.

irst image: the aft deck hatch, secured by 3 belt locks. These locks are usually found on your backpacks, and while they are a bit cumbersome to install, they offer quite some holding power and downward pressure, which is essential for the silicone gaskets inside the hatches’ lids to properly work (would mention about those gaskets in the next post). Similar locking for the forward hatch (2^nd image). There’re 3 locks per hatch, so if one failed, the other two could still full – fill their duty.

Next, I installed the rudder pedals and control lines. 3^rd image: the rudder in retracted position, 4^th image: the rudder in its working position. Thank to the lessons learnt with my previous boat, I redesigned, rearranged every details so that the rudder actions now is very light, smooth, and balanced: kick the pedals lightly and the rudder would follow, release a pedal and the rudder would come back to its neutral position. All control lines tension could easily be adjusted from within the cockpit.

I lubricated with silicone grease all the moving parts of the rudder system, the pivoting points, the lines and pedals, and everything became much smoother. I’m very happy with the overall working of the rudder, though this is still in – dock testing, let see how they would behave while on water. Can’t wait for water trial yet, as there’re still much things to be completed, the bilge pump, the electric box, the hatches’ gaskets, the seat, cart, and a new pair of paddles, etc… still many jobs ahead.

ne more lesson learnt: we can thin the epoxy when glassing too, sometimes the epoxy has such high viscosity (e.g epoxy from the bottom of the container) that it’s a bit hard to wet out the fiberglass, so I added some xylene solvent (less than 1/4 by weight), so that the glassing could go on easier, and the curing time is also prolonged, an important factor in hot tropical weather. Don’t worry about not having enough epoxy inside the fiber, cause we would usually have another fill coat anyhow.

Hull glassed, 1^st image: trim the glass with a small scalpel and peel off the excess. Next, I put the fill coat on until no woven fabric is clearly visible, then slightly sanded the whole bottom. Then I sticked the white vinyl decals for the boat’s eyes and information (3^rd and 4^th images). Next, I painted the deck with 2 layers of transparent PU paint, and the hull with 3 layers. I ran out of PU thinner (butyl acetate) on the way, so I used acetone instead, it’s also a good solvent for thinning PU paint.

After 2 layers of paint on the hull, I slightly sanded it one more time, before applying the final coat. Well, I’m not particularly good at finishing, and like all my boats, all finish is just “barely – good – enough”, not a “very – fancy” look anyhow. But it’s important to have an even, smooth and thick – enough coating to protect the epoxy from UV and other abuses, the “2K” PU paint I used forms up a very hard protection really. In total, I used roughly about 1.2 kg of paint for the whole boat.