Seawave – Oh Rudder, How Art Thou?

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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.

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