Category Archives: Tech

Seawave Rudder MkII tested

Gumotex Seawave main page
Rudder rationale discussed
Gumotex’s 2016 factory version
Making the prototype rudder
Testing the prototype
Update 2019:
I’ve not used my MYO rudder since I made it in 2016. Partly because I’ve only done day trips predicated on nice weather, but also it’s all just more faff and clutter, not least the lines and footboard. As explained earlier, for gumsee07multi-day trips where you must deal with the winds you’re given, it’s a good idea. But even then, you only notice your relative lack of speed alongside others. Alone, you’re as fast as you are.
Rudders are not about steering or tracking as they are on powered boats; in a kayak they’re about enabling a more efficient, balanced paddling effort on both arms by compensating for the boat’s deflection for side winds. In a way the simple stock skeg-shifter (right) will do as well with much less clutter and weight. Or, use this rudder, but locked in position as an ‘articulated skeg’ in place of the Gumotex skeg for shallows and beach parking. That is handy to avoid stressing the stock skeg, especially when the boat is loaded. 

mullamulamap

While waiting for rudder bits to turn up, we went out for an evening paddle round Eilean Mullagrach. It was pretty calm but at no point did I think, ‘Darn, I wish I had a rudder’. When it came to turning corners we just paddled hard or dragged a blade and round we came.
But the Seawave rudder project carries on like a supertanker with a jammed… rudder, if for no other reason than it’s fun to experiment and a rudder can also work as an articulated skeg when locked out – something I may look into when it’s all done.rudderdyl
Ironing out the flaws with the prototype added up to attaching it more securely at the back and making the pedal board out of something more responsive and durable. By coincidence, all these components can be sawn from a single piece of 450 x 300 x 12mm LDPE chopping board (left) which costs from £8 on ebay in a range of colours. This is 50% thicker than the smaller board I used on the prototype plate so doesn’t need doubling up and gluing to make it rigid.
rudm211rudm21At the back I  slimmed the rudder plate right down to a simple strip of 65mm x 450mm, glued a block on the end to better support the gudgeon swivel pivot sleeve and added the crucial second fixing under the portaging handle (left). I also added a triangularish screw plate rudm23underneath (left, with red cord) so it all sits snug in the stern. With the hardware and saddle strap that now adds up to 306g (the rudder unit weighs 450g with its running lines). Even though it’s slimmer than the proto plate, it weighs about the same because it’s now 12 mil. But looks a whole lot neater.
rdd5The pedal board is from the same slab but uses stainless hinges, not zip ties. I’m reminded, you’re constantly making small adjustments as you paddle so pedals need to be as taut and responsive as possible. Once I’d trimmed the board and pedals a bit (left), with hinges it came in at 660g.
rudnee1The board and maybe the pedals could have been made from 8mm if there was some to spare – but an 8mm board wants to be ~450mm wide to sit snugly in the boat’s side channels. Like the rudder, the pedal board will be subject to strong forces in heavy seas so also needs to be solidly jammed in. Meanwhile, I noticed the floor-laminate prototype  board (right) gained nearly 15% in weight after getting wet – a sign it won’t last long. Still, it made a good template.
garbpedalsI do wonder if something like the Grabner rudder pedal bar (left, similar to Gael’s old H2) would be much lighter, as solid and as effective as my board. It costs €70 plus €30 for a pair of Zoelzer pedals.
I can’t really see how I could replicate that alloy footrest bar – out of copper tube filled with resin perhaps (like this motorbike rack)? It’s held securely in place without fittings by being jammed in the channel cavity between the floor and the sides (like my board), but a check with Gael advised me against it. As it happened, I’d pretty much decided the same mid test run (below). A sliding ally bar plus sea water isn’t a great combination and might bend or break, or the pedals snap. I know the ally backrest bar on my Amigo wasn’t up to it and Gael’s backrest broke (though it was ancient). My plastic version may weigh double but should be solid. Interestingly, just as a bag of clam cleats turned up make a quicker way of fine-tuning the rudder pedal lines from the cockpit, I see left that Grabner use them – a good sign.

rudhorserudm221The weather here’s about to crack and then we’re moving south, so in a rush I took the revised rudder plate out for a test with the creaky waterlogged pedal board. Heading towards Horse Island tidal passage, I didn’t need a weatherman to know which way the wind blew: from the WNW at about 12mph. Initially the boat needed constant small corrections to maintain a course, and there was some stiction, hopefully down to the zip ties on the soggy pedal board. I tried a few pedalotight turns and marvelled at the control and how sharply the boat swung round like a pedalo. The rudder plate is now as rock solid as anything fitted to an IK can be. Again, I consciously tried not to correct with my arms, just my feet, which were twitching regularly.
rudm24At Horse Island I was way too early to run the passage, but as it was probably my last paddle here till next year, I decided to head for Badentarbet. Turning north, closer into the wind the micro corrections were no longer needed and the boat ran as if on a skeg, but without arm corrections. I’m pretty sure paddling 20–30° off the wind would have required arm steering, but I just hacked away towards Rubha Dunan on the mainland as the wind increased. When I tried a bit of downwinding protracted rudder juggling was needed to keep the back-end in line.
rudgaprudm23I passed through a channel on the headland and the NW wind got steadily stronger so crossing the bay to the beach seemed to take ages of effort. By now the small corrections I’d been making were no longer necessary, perhaps something had bedded in, the knots had tightened up or like riding a bike I’d just got the knack of minimal rudder movement to keep the boat on track. But upwind paddling is comparatively easy so I tried across the wind, now running over 15mph, and a bit more downwinding which gave me that unsettling Ningaloo feeling. This must be the weak point of a buoyant, windprone IK (especially when unloaded), and maybe all kayaks and canoes too. The chop was only a foot high, but were there a swell of a metre or more, the rudder would be briefly lifting and the stern sliding. I wonder if in a such conditions a combination of rudder and skeg (which is always submerged) might be a way of limiting weathercocking? Or perhaps just more practice is required. There’s also another solution that might arrive here in time to try out.
rudruddAs I neared the beach the wind was hard in my face but I realised I was actually on good form, unlike on the Tanera run with the prototype. So I hammered away with all I had until my strake hissed onto the sands. Paddling hard is all helped by my brilliant, bent-shaft Werner Camano paddle, no less than ten years old this summer. It still clips rudaliotogether with a satisfyingly ‘clunk’ and has very little play. If it ever got lost or abducted by aliens I’d buy another without hesitation.
I was glad I’d got stuck into a longer test run than planned, and am now confident my MYO Seawave rudder is in the ball park. Hopefully the new pedal board will complete the job. 

  • Total weight: 300g rudder plate + 450g rudder + 660g pedal board + ~100g rigging = 1.51kg (3.3lbs), or < 10% of the boat’s weight
  • Total cost MkII version: £20 rudder + £15 rigging + £8 LDPE board + £10  hinges + £2 fittings = £55

rdd4rdd2For about £200 posted I could have installed a 2016 Seawave rudder kit, but from all the images I could find at the time it was unclear exactly how it secured at the back – there must be their version of an unseen triangular underplate, but even then it’s still a stressed-out single point attachment. My additional under-handle fixture eliminates pivoting. And the plywood Gumotex footboard (right) gumrud3appears to sit loose and seemingly will also pivot on that single strap. Production versions may differ and let’s not forget that adding all this complexity also adds a risk of breakage or damage. The simplest solution is usually the best, but the 160-g skeg will always be clipped in the boat as a back-up and a Seawave is controllable (if much slower) with no tracking aids at all. It’s worth remembering: a rudder isn’t about day-to-day tracking, it’s about maintaining a course when the boat gets pushed about in stronger winds. In such conditions a skeg is essential and a rudder is an improvement, as explained here.
rudstashrudderweightsOn the beach, prior to lugging the boat over seaweed-clad boulders, it took only 30 seconds to unclip the rudder mechanism from the plate to pre-empt stumbling and damaging it. Since then I changed the rudder plate mounts with tool-free knobs and an eyelet (left). When rolling the boat up it was best to pivot the rudder plate around the drain hole 90° to pack better.

rudm25

Inexpensive packboat rescue and survival aids

knifewhistleThe other day while leaning over aboard a salmon pen platform, my cherished six-year-old Benchmade Griptilian slipped out of the pfd and into the briny depths. We ummed and ahhed about diving down to retrieve it, but I’m told these pens are 20-metres deep and can hold no less than 80,000 salmon.
It was a bitter loss, all the worse when I saw what a replacement cost new. Long story short I replaced it with a similarly anti-stealth orange PBK EMT Rescue Knife from this place on sale for just four quid. Like they say “you won’t worry too much if you drop it off your lifeboat and [it] sinks into the depths.” No I won’t.
tippyAt 150g it’s a bit heavy but locks out with one of those cheap ‘liner’ locks and has a window smashing stud, should I ever find aquamyself in the nightmarish scenario of being trapped in a sealed aquarium. You also get a pocket clip plus a handy line cutter – a good idea when your packboat begins to acquire yards of lines and straps all adding up to an entrapment risk when expelled from the boat. As it is, I’ve long had a quick-grab Benchmade #8 Rescue Hook permanently attached to my main pfd (see below). With no knife-like sharp point, it’s a good thing on an inflatable running 4.8 psi.
sjakOnce you’ve cut yourself free from your boat, the next thing is to alert others of your distress. Gael had a nifty ‘survival’ whistle on our recent Mull trip. This isn’t just any whistle, this is a bona fide survival aid. You also get a thermometre to check on the hypothermia index, a mini magnifying glass for roasting ants and a compass to help evaluate your drift.
All that for just 99p from China, or under four quid in orange from the UK. The only thing that’s missing is some sort of pea in the whistle body to give it a more punchy warble. I tried shoving a lentil in there, but first go it blew out and temporarily blinded me – which was when the magnifying glass came in handy. Search ebay for “4 in 1 Thermometer Whistle Compass Magnifier Survival” and feel safer out there.

helporwhat

Seawave – Oh Rudder, How Art Thou?

Seawave main page
Skip forward to MkII rudder

ohruddaWithin hours of finishing my prototype rudder I set about finishing it properly, and after a test run to Tanera, made further improvements, listed below, before trying it again.
The whole set-up wants to be mountable/removable without any tools or knots to untie. I used mini karabiners to attach the various lines but snapsrealised snaplinks with a ring are better, as they’re permanently attached so won’t get lost. I recall the fine wire clips on my Incept rudder and after hours of webbery found out they’re called fishing snaps (right). Let me tell you, you can spend a lot of time online trying to figure out if size 00 is bigger than size 8 and still end up buying ones so small you need tweezers to open them. Moving on, some ringed karabiners (black, right) now do the job.
rudd01rud71I only know two knots from my climbing days and still regularly use the Figure of Eight, (right and left) a quick way to put a loop on the end of a line that’s easy to undo. If you want to feed an Fo8 into a fixed ring (like the black krabs, above), just make a loose ‘8’ near the end of the line, then feed the loose end through your ring and follow it back in and around the Fo8 all the way out again. And add a lock knot for good measure.nips
Lines shouldn’t be knotted directly to a fixed object, especially if it’s pivoting, but on the rudder’s lifting pulley there’s no room to attached a krab or mini shackle. The lowering pivot has a hole and channel for a nipple (right). I suppose I could track down a short length of appropriate wire cable, but for the moment it’s a job for our good friends, the zip ties. Lovely family. I also moved the rudder lifting knob to the right side: forward to lift (slightly more effort); pulling back to drop seemed intuitive.
rudd03tanrudIn this pre-optimised form I crossed the two miles to Tanera Mor with a light WSW wind at 2 o clock. First, like a bush pilot, I checked my flaps: up and down, left and right, then started the engine and pushed on the throttles. rudd07
Very soon something was wrong. I was having to rudder hard left and the pedals were leaning way forward. I stopped to knot the lines to take up some slack, but still the boat was turning into the wind and the rudder was very slow to respond.
rudd06With a skeg it’s usually the bow that pushes round on a crosswind. Was the new rudder assembly making more windage to push the back around? More stopping to add knots to the pedal lines. I was also reminded that with a rudder you don’t just set it and paddle away, but are constantly making tiny corrections. You probably to the same with your arms and a skeg, but never notice until it gets obvious (the whole point of fitting a rudder). For this reason a rudder wants to be as smooth-running and taut as possible.
rudd11The forecast was cold and northerly, so, over-dressed in a cag and dry pants, all this foot and arm work took it out of me as I resolutely tried not to correct with my arms. It was a relief to arrive at Tanera’s 200-year-old pier. Mooring up, I noticed my rudder plate was dislodged (right), explaining why the pedal rudd10tension and tracking had gone awry. It was only when I got back that I noticed I’d fitted my nutted ‘underplate’ upside down and the nut had pulled out. Oh Brother What a Plonker. I locked down the plate with a zip tie and readjusted the pedal lines yet again.
rudd05It was also clear that my scrapheap pedal board was flawed. Heels resting on the board (left) put them two inches higher than normal – not good for paddling efficiency, comfort or pedal actuation; perhaps quite good for neglected muscles. That was easily fixed by turning the board around.
After an  hour exploring this historic corner of the island (more here shortly) I headed back and immediately noticed a much more responsive rudder – now you’re talking! It was like driving with all the wheels done up tight. rudd38Lower heels gave a much better angle on the pedals and I noticed I was now operating the pedals with the outer edge of my feet, as I recall on the Incept. Line drag was minimal but now the wood laminate pedal board creaked and the zip tie hinges were a bit mushy too.
imboredI’d already ordered another slab of LDPE chopping board to make a pedal board out of something more water-resistant than compressed dust, as well as the extravagance of proper marine-grade hinges (well, that’s what it said on ebay). I tried a quick bit of disc sailing too but it wasn’t really windy enough – more on that later.
rudd42As I neared Badentarbet beach the g-friend happened to swing by and, showing her some moves, I  was amazed how sharply the boat could turn at low speed in the shallows, almost like a handbrake turn. Of course that’s not a particularly useful rudd04attribute in a kayak unless a WWII mine bobs up in front of you, but it’s good to know it worked. I also got a chance to test my newly bootied Kokotat dry pants – they worked like they should, too.
Back at the house, I realised the pedal lines had been cut before considering the need to move the pedal board forward for tandem paddling. Luckily, more Dyneema turned up next day, so I re-used the former yellow cord for the rudder lifting lines and ditched the saggy red paracord. Much tauter action.
rud61The wheeled cord locks turned up too (right). I had a suspicion they wouldn’t work for adjusting rudder rud62lines and I was right. They need tension from the same direction while snugged up against the edge of a stuff sack or something. I tried doubling the lines with two pulling the same way but the rudlokred Dyneema is too thin, hard-surfaced and slippery to work with these locks. I settled on a ‘truck tarp knot’ then got rud51the idea that the locking guyline adjusters off my Vaude tent might do the job – and they glow in the dark too! My Odyssee has guylines to spare.
Speaking of tension, nursing the loose prototype rudder over to Tanera wore me out much more than it should have – or maybe I just wasn’t paddle fit, having not been out since Mull. I set about making small improvements, including adding two rud64holes in the boat’s back rud63deck triangle (as Gumotex do) to make a cleaner run line for the pivot lines. It’s no great pleasure stabbing a red-hot poker into your favourite IK, but a side benefit is the rich aroma of burning Nitrilon rubber, not some cheap plastic. I’ll track down some nice eyelets later.
Once I realised the rudder board had come undone because I’d mounted the nut plate wrong, it was clear the strap looped to the last deck line sleeves weren’t doing much. rud03The main rud41mount was through the drain hole, which relied on the large nut plate (right) below to stay in place, plus the saddle strap (left) limiting any yawing. The whole plate could be slimmed down to resemble Gumotex’s factory version.
So I think I’m going to follow up on my own speculation and either form a triangular nut-plate below the deck to help keep the rudder plate in line with therudideamk2 boat or I may make a new long thin plate (yellow, left) that reaches back past the kayak’s portage strap. With a slot to get round the handle, I’ll poke another hole in the deck and this way the plate will have two mounting points plus the saddle strap and will not deflect.

rud221Rudder 1.1
While waiting for more chopping boards to turn up, I went out for another run with the Mk1.1 set-up. Much windier this time – 15 to 20mph from the SW. Normally I’d not go out in this, but the point of the rudder was to ease effort and improve control just before such conditions set in.

That was the theory – in practice I  struggled to get out of Old Dornie harbour against the wind and soon had to put in to readjust the pedal lines. What now, ffs? The luminescent Vaude clamps were effective but not a 4-second job like they should be. They can go back on the tent – better line locking mechanism needed.
If I’d looked back I’d have noticed the rudder plate had become dislodged yet again by the forces pushing the boat around. That explained why getting right out of the harbour was such a slog, let alone tackling the 15-knot headwind and lashing rain. Deceptively, there were few whitecaps out there, but a deep swell was rolling through, probably lifting the rudder out of the water. Who’d have thought it was midsummer’s day.
rud222Turning back, I hoped I might get a bit of a run on the wind, but control was even worse – shades of Ningaloo but without the mangos and barramundi. Back at the pier it was a relief to see it was only the rudder plate at fault, although I’d not have been surprised if it was just too windy for any sort of IK-ing today. While waiting for what-do-you-think-I-am-a-bloody-taxi-service? to turn up, I strolled along the exposed shore on the off-chance of finding some LDPE jetsam, but all was glistening seaweed and frayed rope.

rude2Rudder 1.2
I’m running out of time with the luxury of having the sea at my doorstep. That evening it occurred to me the rudder plate was always deflecting clockwise because the lip of one glued-on reinforcement plate underneath stopped it turning the other way. I did what I’d considered initially and glued a thin strip of LDPE to act as an opposing locating edge so the plate sat more securely once saddle-strapped down to the boat’s triangular stern.
This surely should be enough to rude11keep the plate in place, but while I was fiddling I made a template for the triangular nut plate which might further help locate the rudder plate (right). When more LDPE turns up I’ll cut one out and melt another M6 nut into it. if this doesn’t work a longer plate with another through-the-deck fixture below the portage handle (as visualised above in yellow) ought to fix this once and for all.
rude4rude6Other jobs:  trimming off the board’s unneeded flab to make the current haxagonal shape, filing down the edge of the rudder body where the lifting line rubbed (right), and one more tweaking of the rudder pedal lines.
I headed to back to the harbour where it was still blowing about 15mph from the SW but within a minute suspected it was pivoting again, possibly from the pull when dropping the rudder. The added locating strip wasn’t enough. Who knows how Gumotex manage it ruddd1but on this set-up the surefire solution is a second in-line fixing point (as above) and perhaps that triangular under-plate to stop the mount pivoting once and for all.
Partly, these issues are due to underestimating the forces that a combined 120kg of paddler in a 4.5m-long kayak moving at 4mph puts on a rudder and its mount. Add some wind, current and waves and how the small blade is fixed to a big boat becomes critical. Nearly there, brothers and one clear benefit: the ability to sit the kayak on the ground with no skeg stress. I can see me leaving the rudder on there full time and adding some sort of bombproof lock-out to make it the mythical articulated / lifting skeg.

Read about the MkII rudder.

2016 Seawave with rudder option

Seawave main page
My MYO rudder (MkII)

gumrud2The 2016 Gumotex Seawave has had the stern slightly adapted to take an optional rudder kit. They’ve also improved the velcro bands for the optional deck by using Nitrilon, but it’s the rudder that’s the interesting development.
Coincidentally, P1150820I was  halfway through adapting a cheap SoT rudder for my Seawave (right) and the factory version (going for £150 from bluewatersports on ebay.uk) gave me some good ideas. The Gumotex rudder kit could be easily fitted to first-model Seawaves, and possibly to other Gumboats with similar triangular stern decks, like the Sunny and 410C.
gumrud5gumrud61For the time it took to make mine I could have fitted a Gumotex kit ten times over but with only these pictures I was unsure exactly how it was secured. I suspect there’s an additional unseen plate underneath the stern decking to help jam the whole set up securely into the back triangle of the boat. Otherwise the plate would be prone to distortion under rudder forces, giving a mushy response. I got that on my prototype version.
gumrud4The Gumo’s rudder’s retraction method seems to be pull-up-and-in, (right) whereas my SoT example above is a more conventional swing-up-and-over which puts the rudder right out of the way over the back of the boat. IMO this is better for negotiating tight turns in narrow sea chasms where an unexpected swell could crunch your protruding rudder blade.
gumrud3At the pointy end the pedal board looks reassuringly basic (and easy to copy) and the only obvious difference between an old Seawave are the two line guides gumrud1on the stern deck (right) which I added to my boat to make a straighter, drag-free pull on the lines.

Adding latex socks to Kokatat Dry Pants

kokoswiftA few years ago I wrote:

… I deliberately chose [these Kokatat Swift] dry trousers with no sewn-in socks as my drysuit has those. With the Swifts … I’ll just wear short Seal Skins and have no worries about the sewn-in socks getting holed by gravel. Time will tell how they wear and perform. 

Well, I’ve changed my mind. I’ve never been convinced by the Goretex/membrane magic; at least not for hillwalking – I get too hot and sweaty. But making less heat paddling an open kayak on a cool Scottish day, the stuff seemed to work. It keeps out the splash and light rain, but because the leg muscles are inactive, sweatiness is barely apparent. Using a regular eVent hiking cag on top produced more mugginess, but nothing as bad as on the hill and easier to control with the front zip and adjustable cuff cinches. Unlike a hardshell, for an IK there’s no great benefit to buying a regular kayak cag with a waist seal as there’s no cockpit spray skirt to seal it against. If you really want to keep dry all over, just use a dry suit.
omnioOn one trip I found that the Swifts with knackered SealSkinz didn’t really work. ‘Waterproof’ SealSkinz only work for a while after which the clingfilm-like membrane goes and they become saggy sock-bags with insulation qualities no better than woollen socks. In fact, they may well chill damp feet. Wearing my slowly dilapidating Teva Omnium water shoes (left), I now think it’s better to seal dry trousers feet properly with latex socks. IMO latex is easier to repair than socks laboriously made from off-cuts of membrane fabric which, like all that kind of stuff, has a limited life span, especially under the grinding weight of a foot. Bizarrely, Kokatat don’t make pants with integrated latex socks, only membrane, but many others do, like Palm or Anfibio.

Gluing in latex boots
latexerFirst I trimmed the latex on the trousers and the boots to similar lengths. Getting a circumference match is important if there’s to be no leak-prone creasing once they’re joined.
You’d think gluing latex boots to latex trouser cuffs would be simple. Not so it seems. My first go using regular rubber glue didn’t take to the shiny outer surface of the pants’ latex.

I read of using two-part adhesive, even though ami-polythat refers to the tricky latex-to-dry suit fabric seal, not similar latex. So with the leg and the sock remounted on a piece of 5-inch plastic drain pipe (below), I tried again mixing up some PolyMarine Hypalon adhesive. This stuff sticks like a velcro electro-magnet
, but curing times are lengthy and there’s the whole faff of hoping you guess the 25:1 mix correctly.

latexer
latiiI folded back the sock about 3cm on the pipe end and nudged it against the exposed trouser leg cuff (top pic). When the adhesive had cured after 30 mins, it’s another coat (middle pic), wait 3 mins then just roll the sock over onto the leg and lay in with the roller then strap it up for a couple of hours.
There was one small leak, easily fixed.

When cooler weather requires them but you don’t want a full-on drysuit, the sealed pants have been great; you can wade right in without getting wet feet, and with socks underneath the feet are warm and comfy. A few years later one sock started leaking; a tiny hole, easily fixed with a dab of Aquaseal. They say latex is prone to UV so is best kept out of sunlight (which is why cuffs are often covered) and given the odd squirt of 303 UV protectorant.

rudd04

Seawave vs Gumotex 410C + skeg-rudder mod

Seawave main page
The new Solar 3

gumsee02I had a visit from former Olympic slalom trainer and canoeist Jim the other day. He bought a Solar 410C after browsing IK&P and declares it one of his favourite boats. I ran the previous version Sunny for years before I felt I’d squeezed all the potential from it and started changing IKs every year. The Sunny was a tough do-it-all boat and the 410 is the same, but 20cm longer. It was more space but also the greater rigidity of higher-pressure boats I was after.
qefWe were hoping to go out for splish-splosh but for the last few days a cold offshore F4-5 northerly has been spinning off a North Atlantic High and bearing down on the Summers so games are off. Right now the chilling drizzle is nearly horizontal as it blows past the window. Oh hold on, it’s gone sunny now. Is it autumn already?
gumsee03The 3-seat, 410cm Solar went for as little as £550 in the UK or up to £100 less from Boatpark in Czech when on special. Both do free delivery anywhere. The Seawave costs about half as much again.
The 410 is a foot shorter than my Seawave, an inch wider maybe, less slim and pointy at the ends and runs 0.2 bar/3 psi compared to my Seawave’s 0.25 (I run my Seawave sides at 0.33/4.8psi). The old style Nitrilon is thicker so the weight’s the same at 17kg, maybe less with one seat. The Seawave has a bit of a more pronounced keel rib along the middle too, but neither struggle to track without a skeg. It’s just that a skeg enables you to spend less time and effort correcting and so you can power on. Handy at sea, less essential in flowing rivers.
gumsee07gumsee05Jim showed me an interesting mod to make his skeg into a rudder to enable paddling into steady winds. By simply not fitting the back of the skeg into the sleeve, he’s able to pivot it off the front and modify the angle with a bit of string attached to the back of his seat (right). No probs with the skeg sliding out and if it does on a rock, chances are you’ll be close to shore and the boat won’t exactly become suddenly uncontrollable anyway.
gumsee08I usually deal with quartering – ’10 or 2 o’clock’ – headwinds by just pulling harder on one arm, leaning into the wind or repositioning the paddle in my hands longer on the leeward side. I rather lost faith in rudders on the Incept in Australia when it was maddeningly ineffective in controlling the boat in strong backwinds, although I fitted one on the Seawave in the end. But without all the foot control faffery this could be a simple, non-permanent mod to any Gumboat which runs the robust, slip-in black skeg. And unlike my Incept rudder, it won’t come out of the water and be ineffective on steep backwaves.
gumsee10He also showed me a way of simply rigging up his roof rack tie-downs into thin knee braces (left). Like me, Jim agrees they’re a great benefit to paddling efficiency in an otherwise unbraced IK. I have some Packrafting Store ones on the Seawave – a lot lighter than my old SoT braces.
And he also said he’s successfully tried an idea I though of in my Sunny days, but never tried: hull rigidity rods to make the long but low pressure boat flex less. Either two on the sides which requires gluing fixtures to work best, or as he’s found, simply putting a thick broom stick or whatever under the seat in the middle of the boat.


In other news, I’ve been persuaded to cough up 25 quid a year to dump the automated ads on IK&P. I never see them as I’m always logged in, but they sure are tacky.

noadnoad

Packraft Group Test ~ Introduction

pakGTbanner

Supai Matkat • MRS Microraft  • Aire BAKraft • Nortik Trekraft • Alpacka Yak • Summary
2018: things have moved on. See also:
Anfibio Alpha XC ultralight
Longshore International EX280 double
MRS Nomad S1 kayakraft

The range of packrafts has slowly expanded since I bought my first Alpacka Llama in 2010 and Alpacka rafts themselves have changed a lot in that time. But here in the UK people are still slow to see the benefits of these lightweight portable boats. As far as I know there are only two outlets selling packrafts in the UK and I’d guess about the same in most other European countries.
Much of this reticence must be due to the price of these niche-interest boats which, at a glance look not much different from what I call Slackrafts: disposably cheap PVC pool toys. Another reason might be that packrafts appeal more to outdoorsy types looking for a new way to enjoy the wilderness or countryside, but with no interest in acquiring the technical skills plus storage and transport issues of hardshells. They won’t come across these boats very often but as this test clearly proved, anyone can hop into a packraft, set off down river in a straight line and tackle an Environmental Agency Grade III canoe chute. The testers all ‘got it’ and by the end some were already cooking up packrafting adventures.
5botsHere we’re comparing a prototype Aire BAKraft as well as the new Supai Matkat, both from the US; the Russian-made, German-branded Nortik Trekraft, and the Micro Rafting System (MRS) Microraft from China. The unusual Aire calls itself a hybrid IK-packraft, the Supai is an ultralight ‘crossraft’ intended for flatwater use. The other two more closely resemble Alpackas in current or former iterations. My current 2014 Yak made a fifth boat on our test, one which I at least could compare against the others.
These four boats were lent to us by the Packrafting Store in Germany which sells, rents and makes the biggest range of packrafting_store_logopackrafts and packrafting gear in Europe. Sven at the Packrafting Store helped clarify or correct technical aspects in this review but the opinions, observations and most measurements are our own. Some of the more exciting photos are also from the Packrafting Store. We asked NRS to participate but they didn’t answer. Feathercraft’s packrafts are another option, but  they aren’t sold in the UK, and according to Feathercraft’s front page in early 2016, FC’s range of boats is now reduced to folding kayaks only.

pgt-lowboarts


gpt-medwaymapFor this group test it would have been great to set off across the hills of Wales or Scotland, deploy the boats and then follow a river, hop out, walk some more, set up camp and swap notes.
The reality of combining good weather and four other people with the free time to help do all this was slim. So we settled on an eight-mile day trip down the Medway River in Kent (above): me and four testers who’d all paddled (some with trousers rolled up) but had never packrafted. At each lock and chute we swapped boats, so everyone tried each raft at least once.

pgt-meMe – Height 1.83m; weight 91kg
Experience: Into IKs and packrafts for day trips and touring. On my third Alpacka.

pgt-bobBob – 1.78m; 85kg
Lilo incident, Margate 1965. Lea River canoe lessons, Harlow 1980. 

pgt-hanHannah – 1.75m; 75kg
Much canoeing, some kayaking, love touring. Don’t understand eddies, yet.

pgt-loLois – 1.62; 63kg
Dicking about on the Thames in Gumotex IKs and a Dagger. Rely on enthusiasm rather than skill.

pgt-robRobin – 1.78m; 85kg
Scouts canoeing, NZ white water, Colorado kayaking, various inflatable trips, usually with tides.

How the packrafts were weighed and measured
Weighing was done using the classic Salter 1004 SSDR digital kitchen scales. They come with a classy brushed steel finish and still rate at 4 stars on amazon. They were checked and registered 500ml of water as weighing 500g.
gptmeazEach boat was weighed exactly as it came out of the box, and then weighed again as it was actually paddled, without air bags, repair kits or straps (where included). It was then weighed again before going back in the box. All dimensions were also taken twice, the second time using stakes to get the external measurements at the widest points (above). Internal dimensions were taken at the shortest point, usually halfway up the curved tube side. Measurements from other sources may vary; there’s a table at the bottom of each review’s page and the summary for quick comparison.
* Our exterior measurements for the Matkat were 3- to 5cm less than the Store, but 4cm longer and 1.6cm slimmer than Supai states. Unnoticed leaks during the measuring stage may have stopped us pumping the boat up to actual size. 


Construction
All these packrafts are made from pliable fabrics which form airtight vessels when inflated by human power alone. That’s about 0.03 bar or 0.4psi according to the Packrafting Store’s tests and probably too low for a regular manometer to measure accurately. The BAKraft uses an in-line ‘squeeze pump’ to potentially attain 0.17bar or 2.5psi – firmer than most recreational IKs. All the models used here except the Supai were pressure tested to an impressive 0.5 bar (7.25psi) by the Store without exploding into a blaze of harmless TPU shards. As a comparison, my old Grabner ran 0.3.bar as was as stiff as a gangplank.

Hardshell-like rigidity is an inflatable boat’s goal, and while design and shape might come into it, some rafts become more rigid than others and so perform better. The best rafts use a fabric (or construction design) which becomes stiff when inflated but is pliable when folded (especially at low temperatures) as well as being durable against sharp impacts and abrasion. Among other things you could add resistance to UV rays, ready supply and ease of assembly in the factory, repairability on the trail, and a range of fabulous customer-friendly colours.
gpt-MRSsewBroadly speaking the hulls of the Alpacka and MRS use ten panels of urethane (TPU) coated nylon fabric which are sewn together. Tape is then heat welded over the seams. The Alpacka fabric is only coated on the outside (pgtYAK15below right); the Nortik (below left, also ten hull panels) uses a similar double-coated fabric to the MRS (left; green, but not our Trekraft), but the Nortik’s seams are heat-welded with thicker tape (no sewing). 
gpt-trekseamDouble-coating adds weight and other technical aspects of proprietary coated fabrics vary greatly; they’re often specifically formulated for a raft manufacturer. The benefits of an inside coating are a second barrier to punctures when a light scratch to the exterior reaches down to the fabric core but doesn’t actually cut through it.
gpt-underbotsThe floors on the Yak, Nortik and MRS are glued on then taped over (Nortik on the inside, the other two outside). They’re typically two or three times the denier rating (thread weight) of the hull fabric.
The Alpacka uses something called ballistic nylon which sounds cool but I’ve found is far from bulletproof. No part of an inflatable raft weighing just three kilos can be expected to be. Occasional repairs are all part of ownership, like a bicycle’s tyres. So is rinsing any grit out the boat before it works its way into the nooks and crannies. On the right click the extra large picture to have a close look under the boats and compare workmanship.
pgtMAT07The superlight Matkat is in a class all of it’s own, entirely made from 75-denier ripstop polyester with a single urethane coating on the inside, the same weight (and sealing method) as an MSR water bag. The red picture below right is of another Supai we tried which you’ll see had a diamond pattern on the surface. su-msrfabThe black Matkat we used here had a plain surface like an MSR bag. On both boats the four panels (floor, inside, top and bottom hull) are then heat-welded together.
 It’s possible to repair these seams with a hot iron (or glue).
pgtBAK30The Aire BAKraft prototype we tested used a thin and slightly stretchy urethane  film ‘inner tube’ or collar supporting the hull, and a much thicker and stretch-free urethane-coated yellow nylon fabric for the I-beam floor (left). These bladders or ‘AIREcells’ as Aire calls them, are contained inside a sewn-up shell of fabric which need not be air- or watertight. If I interpreted the owner’s manual correctly then the BAKraft’s green exterior shell is made of Spectra and the grey interior of lighter-weight Dyneema fabric. You may know stretch-free Dyneema guy lines found on better tents. 

pgtBAK31The urethane bladder can be accessed for repair via long zips (left); the nylon floor can be pulled out for repair from each end. On packing or refitting care must be taken not to twist the bladders. I’ve never been a fan of it (for reasons explained later) but this AIRECell system has been used by Aire on their PVC whitewater rafts and IKs for many, many years. With minimal seams compared to a traditional packraft hull, air retention is excellent.
On all the boats seatsbackrests and decks (where present) are typically made from urethane-coated nylon with seams or joins heat-welded and maybe taped.

pgtMRS11Inflation/deflation
If you’re combining walking with navigating bodies of water – packing + rafting – you want a boat which inflates and deploys without any faffing about. In this respect the Microraft was the best of the bunch. It used the proven screw-in inflation bag (see video below) and, being a small volume boat, took about ten ‘scoops’ to fill up. The main valve cap is attached with a short plastic ring tab – no fiddly bits of string. Top off the air pressure by blowing all you got into the twist-lock valve and with practice you’re good to go in three minutes.

In the video below, from arriving at the beach to paddling away
takes about 8 minutes. Speeded up 15x. A jet passes overhead.

yak-airbooMy Yak followed exactly the same inflation procedure, but being a higher volume boat (a little bigger than the one in the video above) took twice as many ‘air-grabs’ to fill up before topping off with lung power. Every time I do this I wonder whether my super-thin airbag will split or unravel at the seams if I scrunch too hard. I can feel the air leaking through the sides.
pgtTRK08Like the MRS, the Trekraft’s airbag is also made from a reassuringly thick fabric, but is spoiled by a push-in plug, even though there’s obviously a thread pgtTRK03in the boat’s port. Compress too hard or if it’s wet and the bag plug might pop out, so inflate gently. Instead of using a twist-lock to top-off, the pgtTRK02Trekraft has a one-way spring valve with a cap (which came adrift and eventually got lost). This valve (above right) is dead easy to use and avoids the risk of over-tightening a cheap plastic twist-lock valve (as on older Alpackas). But when airing down, with the spring valve you can’t suck and seal the remaining air out unless you jam something in the valve as you suck. Packraft or IK, this ability to suck your boat down is handy for compact packing.
Next comes the Matkat. No airbag supplied even though the Supai website states: ‘We are working on developing an inflation sack to work with our valves hopefully we will have it released in mid-2014.’ When we tried the smaller red Supai Canyon Flatwater II in late 2013 we found it took about fifty breaths to fill, plus topping off. The higher volume Matkat takes about eighty breaths. I like breathing but that’s not something I’d want to do more than a couple of times day to save the 100 grams of an airbag.
pgtMAT08Unlike the Alpacka, Nortik or MRS, the Supais use a male threaded dump valve which protrudes from the boat and onto which screws a cap with a thin tube and the twist lock valve on the end (right, red boat) – a neat and simple system that’s just about accessible for on-board top-ups.
supaivalveAlpacka use an identical threaded valve port but on their air bags; it’s a regular American plumbing ¾-inch size. If I had a Supai packraft I’d get an Alpacka airbag for $20 and then either find a female-to-female plastic connection, or jam on a short section of clear plastic tube to join them together. That way I can save the hyperventilating for Glastonbury.
pgtBAK23That leaves the BAKraft. Even before I received the boat I had my doubts after seeing pictures of the convoluted inflation system which Aire suggest.
The BAKraft uses Halkey Roberts (or very similar) valves, as found on proper IKs and whitewater rafts: one in the floor and one for the urethane bladder that fills both sides of the hull, or what what they call the ‘collar’. These valves work like car tyre valves (or the Nortik top-up) – a spurt of high pressure opens the seal and a spring seals it shut – except that you can lock them open by pushing and twisting beg02the valve stem. This is necessary to deflate a boat easily, or to loosely pre-inflate it without having to push against the valve spring. These valves are really designed to be used with pumps not flimsy air-catching inflation bags, far less lung power. A simple and compact push-fit pump like a K-Pump will work. A high-pressure stirrup pump with a ‘Summit’ bayonet connector on the end will be even quicker, but is way too bulky to travel with.

pgtBAK06gpt-BAKair1With the BAKraft you’re supposed to use the backrest/cargo bag as an inflation bag and scrunch air into the boat via a tube fitted with a bayonet connector (left). But the backrest bag’s weight, odd shape and relatively small volume makes this task awkward, even past an opened intake valve which is still a restricted airway. I gave it a go  but soon saw that, while I’d get there in the end, it was going to take ages. gpt-BAKair2
Once the boat has ‘shape’ you’re then supposed to quickly close the boat valve then splice in a low-volume/high-pressure hand-squeeze pump into the ISC bag. The squeeze pump has another one-way spring valve in it: charge it with air from the backrest then squirt air by hand past the closed valve until the boat is firm.
This squeeze pump is quite a clever idea but at about 150cc a go will take a while to do the job. Sorry to say I wasn’t even curious to find out how long – I’d guess at least 15-minutes for the whole inflation, same as it took to pump up my 4.5-metre kayak the other day with the one-litre K-Pump Mini. So instead I reached for my Bravo stirrup pump – it Bagpipertook two minutes – and on test day I brought my compact K-Pump which took about twice as long.
I see now that I’ve actually RTFM I used an alternative method. The image above right suggests you don’t use the backrest bag to charge the squeeze pump, but just blow then squeeze the hand pump directly using an oral tube, like a silent bag pipe. If I’d thought of that I might have tried it as it’s a much less clumsy way of topping off the BAKraft.
pakv1All the other packrafts here run at an air pressure that’s governed by the lung power you can exert through the top-off twist valve (left). But with a one-way valve you can pump more air into a raft (that goes for the Trekraft’s top-off valve too, now I think of it). The BAKraft is made to run an IK-like 2.5psi although you’re warned not to over-pressurise or allow it to happen. That can be easily done of you get carried away with a stirrup pump or leave the raft out in the hot sun.
It may have seemed clever to give the necessary backrest multiple uses, but it works only a little better for filling the boat with air than it does as a backrest (see review). I’d recommend getting a $20 Feathercraft inflation bag which comes with the ‘Summit’ bayonet fitting from their BayLee packrafts (they also use Halkey-like valves). And if you don’t get on with the oral/hand pump system, then get a 600-g K-Pump Mini too. I’d guess using both these devices will more than halve the inflation time.


gpt-groupieFrom the four corners of southern England the throng gathered at Tonbridge Town Lock, the boats got pumped up, cooled off in the water then topped up some more. Then after a quick groupie, we set off down the easy first chute. I took it upon myself to get in the Matkat while I was still feeling fresh.

 Supai Matkat • MRS Microraft  • Aire BAKraft • Nortik Trekraft • Alpacka Yak • Summary

Drop-stitch IKs: Razorlite, KXone, Yakkair, etc

Updated summer 2020

• Read also Decathlon X500 and Gumotex Thaya and Rush
• … and this illuminating post
Slider discussion on French forum

As predicted in IK Construction a few years ago, before long someone was going to find a way of making a decent IK entirely from drop-stitch panels.

It seems Sea Eagle in the US and KXone and Airkajak of Germany and Bic Yakkair in France were among the first to do just that, with three-chamber DS IKs made entirely from Selytech DS PVC developed by Woosung in South Korea. Woosung is the world’s biggest manufacturer of IKs and sell their own boats as Zebec Pro (Z-Pro and KXone). The boats are actually manufactured just over the Yellow Sea in Shandong, China. 

There are now several full D/S IKs to be found on eBay under various brands you’ve never heard of. The Bluewave Glider left is an 18-kilo 4.7m footer that’s 76cm wide and goes for just £659 for the full kit, or 3.9-m singles from £550.

Below, Allroundmarin out of Austria is another importer bringing in the same Chinese-made DS IKs re-branded under their name and adapted with their own colours and features such as a footrest strap and what looks like a drain hole through which you can clamp an electric motor. The 4.7m FD/SIK goes for around the same price.

A fully drop-stitch (DS) IK is made of three flat panels which each run at least three times the pressure of a regular tubed IK. This gives the boat the rigidity (if not the streamlined form) of a hardshell, while retaining an IK’s light weight and roll-up portability. Full description of DS here or keep reading. In a way, DS IKs resemble a simple, self-assembled three-board canoe, as shown left.

DS IKs started with easy-to-make drop-stitch floors (derived from iSUP boards) but retaining regular round side tubes. Some floors were a removable option (Advanced Elements), on others the floor is integrated (Sea Eagle 385; Gumotex Thaya and Rush). The boats on this page are the first generation to be made entirely of DS panels. See image below for the three types of IK: tubed; DS floor; fully DS.

Sea Eagle’s tandem 473RL RazorLite, the two larger Kxone Sliders (below) and the Yakkair Full HP are a slick and lean group of full DS IKs. And setting aside the fun element of speed, a fast IK is an efficient and safe IK on which you can range further or retreat quicker if conditions change.

I don’t claim to have any experience of these new boats yet: it’s all the usual online speculation IK&P is so well known for. I did try to buy one direct from China as this guy did, but got no reply. Sea Eagle and KXone make some hugely wide bladder tubed ‘American’ IKs – recreational boats which are great for standing up and fishing from while your dog scratches its ear, but are less suited to all-day IK touring which is the niche activity we like here at IK&P.

Sea Eagle’s 473RL RazorLite double is 4.73m (15.5′) long and just 76cm (30″) wide. Weight is claimed at just over 17kg (38lbs). The DS panels run at 10psi (0.67bar) and are 10cm thick, giving a massive claimed payload of 340kg.

slides

KXone’s two similar boats (right) are designed in Germany but made at the same Chinese factory in Weihai for Woosung in Korea and are rated at 8psi (0.55 bar):
Slider 445 (14′ 7”) • 85cm (33.5”) wide • 17kg • 225kg
Slider 485 (16′) • 85cm (33.5”) wide • 20kg • 250kg

BIC Yakkair Full HP 2  4.1m (left; 13.5′) • 85cm (33.5”) wide • 15.5kg • 210kg • 8 psi • Video below: barely a millimetre of sag!

Air Kajak’s 10psi Airtrek 465 is 79cm wide and weighs 20kg + seats.

kzostand

You notice the two Sliders and BIC are 10cm wider than the Sea Eagle RL. This may be because the 2017 models at least, are pitched as SUP IKs, in that you can stand in the boat and work those core muscles! With the popularity of iSUP boarding, this is quite a clever sales gimmick and an activity which is easier to do with a wider floor, although sit-down paddling performance will suffer.

Lined up against my latest IK compassion table (below), all those dimensions are very much in the ballpark, with the slim Razorlite getting a very high L/W Index of 6.22. The RazorLite 473 is over 20cms longer and a couple of cm narrower than my old Seawave (among the faster touring IKs). The longer but wider 485 Slider has an LWI of 5.7 – same as my Seawave. The shorter BIC comes in at 4.82 – not so good and a bit more than a ‘hybrid’ Thaya.

These DS IKs are simply three flat slabs of DS fabric. Conventional tubed IKs like old Gumotex can vary the diametre each chamber (floor and two sides) to help give a curved hull in both axes, particularly each end of the floor. Somehow, even with the formed hull and stern pieces, the plank-like floors of a DS IK (right and left) have zero rocker, suggesting these boats will track very well, but may be hard to turn.

One French Kxone owner admits that after a year of use… son défaut c’est qu’il est hyper directeur, même sans dérive … [‘It always wants to go straight, even without the skeg’] and he’s thinking of installing a rudder. Another reviewer from the US says:
‘The 393 RL tracks very well, almost too well. I trimmed 3″ off the skeg for better clearance in shallow water and it still tracks straight and true. It’s easier to turn now as well, another nice improvement.’ Here’s another short review from the UK.

This is because these boats effectively have a frontal keel or a very well defined bow (right: Sea Eagle Fast Track). I can’t help thinking that having to fit a skeg to the front of a boat is an admission that the flat hull will not track well, even with a conventional skeg at the back. A frontal keel or skeg-form bow will make a boat track very well but make it very hard to turn, especially when it’s over 4.5-m long.

And the flat floor and box profile (right) may make edging – leaning on one edge as you turn or counterbalance on waves – trickier; the secondary stability (leaning right over) may be on a knife-edge. You’d need thigh straps to manage that, but anyway, it’s all speculation – the proof is in the paddling.

For the full story on drop stitch (DS) click the link. Short version: the mass of non-stretch ‘space yarn’ stitched between the two woven fabric surfaces of a hull panel (above right) enable much higher pressures while crucially constraining the panel from ballooning out. We’re talking up to 10psi (0.67 bar) which is more than double what even the better regular tubed IKs can run. Pressure has long been the weak link with traditional ‘lilo’ IK floors which need I-beams (above right; a similar idea to DS), to retain a flat shape. I-beams are expensive to make and – without PRVs – vulnerable to damage or rupture when over-pressurised through neglect or when left in the sun.

Easy-to-make round side tubes can handle high pressures fine, but take up a lot of space which makes for a wide and tall but also a cramped IK – one of their biggest failings. DS panels get round some of this. High pressure is also desirable in an IK to reduce longitudinal sagging under a single paddler’s weight (above). Some manufacturers use metal frames to minimise this, but in my experience it’s a clumsy solution.

Using DS technology these kayaks can easily attain hardshell sea-kayak-like lengths (and so, speed) because the high-pressure DS hull makes a rigid box-like structure; the boat won’t ‘taco’ or fold up between waves as most long 0.2 bar/3psi IKs like a Gumotex Solar 3 will do.

dspreswarn

It’s notable that there are no PRVs on these boats, presumably because the very high density of evenly spread space-yarn and the can handle over-pressurisation when a boat is left in the hot sun. Some do have clear warnings at the valve not to exceed recommended pressures and which must be calculated within an over pressurisation safety margin. You’d think the pressure increase in smaller volume D/S floors will be less extreme than fatter I-beam floors. These boats’ smaller volumes also mean they’re a bit quicker to inflate than a comparable regular IK, despite the effort in reaching 10psi which will require a hard-bodied barrel pump.


Some claim D/S floors won’t last as long as I-beams with PRVs. That may be true and much will depend on the quality of the original manufacture/assembly, running the correct pressure and where possible, leaving the boat in the water on hot days so the large water contact area keeps things cool.

The Sea Eagle features two drain valves in the floor – I’m not sure why unless it is genuinely self-bailing? To drain an open IK, you simply flip it over. Drain valves seem another thing to go wrong, as RazorLite owners have already found (see below). It’s not like these are truly self-bailing boats – open the valve and you’ll be sitting in water. Kzone and Airkajak now have the drain plug right in the stern (left) which makes much more sense. stand it up and let it drain. As for the red Kxone graphic above; I’m not sure I fully understand it but there appears to be a water-collecting cavity between the floor and the sides which requires draining one deflated.

Selytech-DS-Fabric-Construction_2-yellow-1024x569

Both brands are cagey about the actual Selytech fabric. There seems to be a word missing and that missing word is of course ‘PVC‘ – poly vinyl chloride: the Devil’s Fabric! But not all PVC need be nasty slackraft material, as this page explains.
It may not be considered very green, but the PVC is applied as an air- and watertight coating over a polyester fabric base, just as with ‘rubber’ hypalon.

sai13

These boats also feature rigid moulded ends in the one-piece body to help slice the boat through water. This element of streamlining is typically a weak point on ‘broad-nosed’ IKs (left) where a sharp bow and stern are difficult to fabricate purely from inflatable tubes. The grey Incept on the left (based on the old Semperit) does a pretty good job and was a fast boat. The bulk of these rigid fixtures, as well as the dense DS panels, may make the DS kayaks less easy to pack compactly than regular synthetic rubber IKs.

Not for the first time I see an IK manufacturer use ideas I’ve tried on my own IKs. In Sea Eagle’s and Airkajak’s case it’s a simple footrest tube with an adjustable strap which I came up with a years ago. It’s so much simpler, versatile and more effective than some of the mushy ideas I’ve seen used on IKs. Kxone use a padded strap; less good IMO.
In any kayak, a solid footrest helps you connect with the boat and pull in powerful strokes. And as an IK doesn’t have the benefit of a hardshell deck to brace knees off, a footrest is all the more useful. Even then, I’d say both these DS IKs would benefit from thigh straps, especially the slimmer Sea Eagle. Both boats are spacious inside, with little chance of feeling nicely wedged in,like a packraft.

The KXones are pictured with a removable deck for single or double paddlers. Once you realise this boat is as rigid as a sea kayak but with no deck, adding one (or at least some sort of deflector at the front) may be a good idea for managing waves more than a metre high. A regular IK will bend with waves a little – a stiff DS IK will cut in and swamp, especially if loaded.

Over in Canada IK World ran a comparison between her old style DS-floored Sea Eagle FastTrack and the 393 solo Razorlite, as well as giving a fuller recreational review of the 393.

You may like to scroll down and read some of the reader’s comments about issues and returns they’re having with early Razorlites. She mentioned the new DS boat was less stable, but to me the ‘stability’ of the yard-wide FastTrack is beyond the pale. About 76-cm on the 473 is still 30-inches and I felt quite safe in my 69-cm wide K40 right up to the point when it was coming in over the sides (thigh braces helped greatly, I admit). Both boats appear wide but the sides actually taper inwards towards the floor, so they’re narrower than they look. And both come with an easily fitted slip-in skeg that’s pretty tall so will drag in the shallows. Perhaps that pancake-flat floor needs a big skeg to keep it on track.

iu

I’ve never been a great fan of Sea Eagles’s regular, PVC watersofas (exemplified by that thing on the right), but good on them and KXone for upping the game with the full DS IKs. It’s a big step in making IKs less ‘bloat’ and more boat. Many people are already mistaking them for hardshells.

Modifications to my Gumotex Seawave

Seawave main page

yaldingGrappling to get the boat out of the muddy Medway river at Yalding the other day put a light scrape on the hull. It reminded me that, along with the PRVs, another winter job was to fit a protective strake under the bow where most scraping occurs. Better to get the protection in early while the boat is newish.
Upstream the Medway had been high and even had a noticeable current. Two-up we were flying along at a good 5mph+ at times. Some of the chutes I was looking forward to were closed even though they look merely ‘sporty’, but then weir by weir, lock by lock the level started dropping so that never before seen eddies, whorls and rocks appeared. The super-sporty chute at Sluice Weir Lock was high and dry (clambering out onto the nearby jetty was a real effort) and by the time we got to Yalding near the end there was a 6-foot drop with muddy banks to either side on which you sank up to your knees.
medclosedSoon covered in muck, we managed to clamber out over the mossy weir wall and haul the boat up. Had I been less cavalier about my preparations I’d have read what was going on right here. Looks like the Medway chutes will be out of action till March (right). Knowing that would have saved half the next morning hosing myself and all the gear down.
strakerBack to the strake. A 70 x 15cm Hypalon off-cut (close enough to Nitrilon) was 14 quid on ebay and once trimmed left enough for another strake or two. I had some Polymarine two-part adhesive (below) and glued the strip to the boat’s curved form with the floor inflated, ami-polyeven if that meant working the roller to press it all together was less effective. I then slathered some Seam Seal around the nose of the strake to protect it from unpeeling (less runny Aquaseal would have been better but a Seam Seal tube was open. More on glues here).
footerWhile the boat was filling the hallway and causing a hazard to domestic navigation I also bodged up a better system for the all-important footrest. A bit of inner tube now counter-tensions the footrest from the bow to keep it in position. It means the thing is now fully adjustable across a wide range ofsw-cantilastic positions, can easily be fine tuned from the water, removes in seconds for boat cleaning/drying and needed no extra fittings glued to the boat. Once great thing about the Seawave is the multitude of attachment points on the floor and sides.
While on the river my aged Mk1 Alpacka U-seat base went flat, split right in the U. This seat is part of a lighter and comfier system I brought over from my Amigo – an improvement on the one-piece Seawave seats. It’s currently unfixed to the boat and the thin nylon must have ripped while yanking it into position on the river after getting back in. Again, I’m trying to avoid gluing extra D-rings to the hull – they’d limit seat base adjustment options anyway.
sw12Better then to attach the seat base to the base of the backrest (right) with a couple of zip ties. The whole backrest/seat base can then slide forward and back off the backrest side straps and it all unclips from the boat in less than 3.7 seconds. alpacka-seatI glued up the punctured U-seat but it won’t last, so I’ve ordered MkII Alpacka seats (left) from Packrafting Store: €70 delivered for a pair. From Alpacka US the seats cost $25 but their auto-calculated international postage is nuts, let alone tax and VAT issues. These seats have the U filled in like a webbed foot: stronger and less floppy for just ~12g extra weight.
Since then I decided not to fit the seat base to the backrest, but simply attach it to the floor between a similar the same adjustable strap and elastic tension system used on the footrest. So far so good. Will add a photo next time the boat’s out.
SOTstrapI’ve also ditched my old my SoT thigh straps (right). Nanfistrapsicely padded and effective though they were, the brass spring connectors and padding made them feel heavy and bulky at ~720g.
Instead I got some non-padded Anfibio packrafting straps from the Packrafting Store (without their biners or D-ring patches). With my biners they come in at 270g. The delta-straps dangling off the sides are a clever idea, designed to give a fpy165more direct pull when rolling a packraft for example. Can’t see myself doing that in any of my boats, but if there happens to be a handy attachment point on the Seawave’s hull I may give them a go (normally you’d have to glue on the D-ring patches supplied). Whether you’re rolling or just paddling, in rough water the more direct connection with the boat the better. I’m a big fan of these light but effective straps now. No need for paddling