Tag Archives: IK rudders

Seawave 2: Mk3 rudder (MYO)

Gumotex Seawave main page

See also

Rudder rationale discussed
Gumotex’s 2016 factory version
Making the Mk1 prototype rudder
Testing the Mk1
Mk2 rudder tested (gets to the point)
Mk3 rudder tested

Rather like sails where I Made My Own, lost interest, then returned with a proper WindPaddle, after five years I’ve come back to the idea of fitting a rudder to Seawave 2. Mostly, this was inspired by a much simpler pivoting footrest tube idea from fellow Seawaver Jules, replacing cumbersome and bulky foot pedals. A rudder ought to make the Seawave more useable in a slightly greater range of conditions, including sailing which I tried again recently.

Jules’ footrest pivot

I could have bought the Gumotex rudder kit for just £219, but as always it’s more fun to piss about for hours and days on the pretext of saving money and conjuring up small improvements. IKs sit higher than hardshell kayaks, so I coughed up 25 quid for the longest rudder mechanism I could find on ebay: 510mm. It weighs 550g.
The stern-mounted rudder plate started as a slab of was a chopping board, then became an aluminium plate additionally located with velcro pads, as Jules and Gumotex use. I found secure clamping of the rudder mounting plate to be important to stop it turning on its axis. There is perhaps more torque on the mount than might be expected when a rudder blade tries to turn a 4.5-m boat. As you’ll see I ended up making a Mk 3.1 rudder mount in a mixture of soft and hard chopping board, as well as a Mk 3.2 in aluminium. There’s a 20g weight difference.
Another bright idea idea Jules had was running the rudder lines out of the way under the deck velcro flap and inside thin tubing. That largely eliminates any exposed lines. I also liked his idea of controlling the rudder by pivoting a drainpipe footrest tube from the centre, eliminating the need for cumbersome foot pedals. Overall the whole mechanism: rudder, mount and clamp (220g), cords and tube (50g), adds up to less than a kilo and under £50 (some bits I had already). Eliminating foot pedals was the main saving in weight and bulk.

Mk3 Rudder for Seawave 2

Items needed:

  • Ebay rudder assembly from £20
  • Piece of HDPE chopping board, 3mm x 400mm x 60mm, aluminium bar, or similar
  • Stick-on velcro
  • Hand clamping knob and nut
  • 6 metres of PVC (or PTFE) pipe with 5mm internal diameter
  • 11 metres of 2mm Dyneema cord
  • 4-inch ø x 30cm plastic drainpipe footrest (if not used already)
  • 2 metres of 25mm strap
  • A few mini snaplinks, fish snaps or similar

You may also like:

  • Knob for rudder lift, cinch locks and clamcleats
Make 2 central slots, then attach the strap

I already use a drainpipe as a fixed footrest. At 25cm wide, another 5cm would still fit between the Seawave’s sidetubes and may give a bit more finesse and leverage to rudder steering. If this proves the case with mine, it’s an easy swap.
Drill and/or hot-knife in two adjacent slots in the middle and feed the strap through. You must fix the footrest to the strap so there’s no slippage. A big knot inside will do. Thread the strap’s loose ends through the stock footrest attachments buckles on the boat’s floor. You can now easily re-position the footrest tube forward or back for tandem or other sized paddlers. This is handy whether you use a rudder or not.
While fine in the straight line along the hull top, putting a bend in the soft PVC tubing down the insides of the hull caused too much drag on the lines. So to avoid wear on the grey Hypalon, I just chopped the PVC tube back and stuck on some tape. (As you can see I need to add another strip for the tandem position). It’s probable the harder PTFE tubing Jules used causes less stiction, but having the rudder line exposed near the footrest-pivot make adjusting clamcleats and cinch locks easier.

I stumbled on quite a fast and easy way to fine tune or readjust the footrest pedal tension: inline clam cleats (or cam cleats or rope locks) which I came across during my V-Sail experiments years ago. Feed the line through as shown below; centre both rudder and footrest, then cinch up and you should be good to go. Once you’ve established the right line length through the cleat for a certain fixed position, it can help to ‘memory mark‘ the cord (as I did in red). Though I bet once I get on the water and use the rudder a bit, they’ll go off alignment, so probably better to wait till then.

You need enough rudder line slack to slide the whole pedal-footrest forward about a foot when paddling two-up. Loose ends can be tidied away with cinch locks. Eleven metres of Dyneema cord is enough to do this job on a Seawave, including a single rudder lifting line. (To push and drop the rudder too you’ll need another 3m.)

Rudder mount plate
The 10mm red chopping board I bought was actually quite bendy (LDPE, not HDPE?) compared to other bits I realised I had all along. The less play in the rudder system the more responsive it will be; an IK’s stern mounting is mushy enough.
This time round I copied Gumotex’s idea of using small velcro pads to stop the rudder twisting on it’s pivot-clamp axis. Initially lacking stick-on velcro, I glued plain velcro, using the PU glue from the Gumotex repair kit. For one-part glue, it seemed to fix the velcro pretty well but if not, some sticky-back came in the post.

I knew from last time I made a rudder the under-plate shape helps eliminate pivoting of the mount, but you can draw out the truncated triangle by simply tracing the converging top seams at the stern, then make the under-plate from whatever you got. I used a bit of plywood: jam it in snugly, mark the point under the stock drain hole, remove and drill. I glued and taped a nut to the back of the ply and added a bit of string to help pull the under-plate out.

I would have rather made the rudder top mount plate from ally but with little more than a hacksaw and a kitchen stool, lacked the tools to do a neat job. Then, while waiting for parts to arrive, I realised it was possible to buy ‘aluminium bar off cuts’ on ebay (right). Using the word ‘bar’ was the key. This place, or others like it, sell various sizes, including 3mm x 400 x 60mm for 7 quid.

I’m pretty sure most kayak rudders come with a 48-mm pivot pin of 9mm ø. Or was it originally 3/8″s, which is 9.5mm? The pin slips into a 10mm gudgeon swivel sleeve/tube. Some hardshells have this tube moulded in the stern; on an IK it must be built into the rudder mount plate.
Above left, you can see Jules (as well as Gumotex) integrate a gudgeon swivel tube into the end of the mount plate; a tricky thing to do accurately with a just a hand drill, though Jules’ thick plate makes it a bit easier. On my Mark 3.1 white HDPE mount, I glued layers of the old red LDPE into a block of plastic, then drilled a 10mm hole which works OK.

When it comes to an ally rudder mount, online you’ll find stainless steel kayak rudder pivot ‘C’ brackets for a fiver. They weigh 57g and are usually screwed to the vertical stern of a hardshell, replicating the gudgeon tube. Even though they’re only a fiver, it seems impossible to buy these from anywhere else but the Far East, and it would be more than a fiver’s work to fabricate that shape from hard stainless steel.
I bought a pair anyway; they arrived in a fortnight, but hole diameters (not stated in the advert) were 11mm, meaning 2mm of play with my rudder pin which feels too much. Oh China, your poor manufacturing tolerances let me down! So I glued on some 10mm washers to eliminate the slack. I’d have been better off making something after all.
It had occurred to me I could have bent my 400-mm piece of 3mm ally into a full ‘C’, either curved round a pole, or bent on an edge at two right angles, as up above left in cardboard. Tweak the alignment and precisely drill two 10mm holes and the rudder swivel mount and plate are all one piece. In fact, that 3mm alloy plate I bought was pretty stiff, so I settled on a simple L bend (and without a vice, even that wasn’t perfect), then glued and bolted on the Chinese ‘C’ bracket.

Rudder pulley
Rudder blades have a hole in the back so the pulley can lift and lower the rudder near a shore. For the moment I’ve decided to keep things simple and only use a single lift line, not a doubled-up line (another 3m of cord needed; 14m total) to lower the rudder as well. I intend to use the paddle to reach back and flip the rudder into the water. If that is a poor idea, I can easily add a two-way rudder line.
On packing up I realised this line needs to be in two sections if the rudder and plate are to be easily removable when rolling up the boat. The join can be at the back near the plate. As you can see I ran out of Dyneema and used an orange shoelace.

I fitted the lift line along the sides, using the deck support rib tabs and running through spare bits of tubing to avoid wear and aid smooth running. I fitted a tension-adjustable knob at the hand end of the lift line on the left, though anything will do. Pull forward six inches to lift the rudder. Flip the rudder back down with the paddle blade.

Does that flat, 4mm front edge of the rudder blade need chamfering to cut through the water, or am I other-thinking it? Who knows but watever you do, keep the skeg handy in case the rudder plays up.

Next job – see if it ruddy well works!

Incept K40: a windy weekend

Incept K40 Index Page

Normally on a decent weekend up here (as pictured left) there’ll be half a dozen vans with their distinctive kayak racks parked down at the beach. This weekend they’d all clearly read the forecast, but keen to get some hours in for an upcoming plan, kayaking chum Jon took a chance on the long drive up.
The good thing with the lie of the land hereabouts is there’s usually somewhere sheltered to go wherever the wind’s coming from. Except perhaps during a northwesterly as predicted for Saturday and which bowls straight up the skirts of the prevailing lochs and valleys.

With it all laid out on my doorstep, Saturday afternoon we put in at sheltered Old Dornie harbour (left) and tried to head out round the adjacent isles, but I lost my nerve at the sight of the oncoming swell and increasing wind. Eager though we were, we reverted to Plan A, turned round as if on a tight rope and settled for a couple of hours solo re-entry practice, something I’d yet to try in my Incept K40.

Being a hardsheller, Jon works on his roll from time to time, but hasn’t quite got it nailed yet. He’s got a good alternative though, re-entry and roll, they call it – getting himself into the semi-submerged kayak on its side and then once in and braced, doing the hip flick and paddle float lift to get himself upright, at which point he pumps out the hatch compartment.

Me, I tried lunging onto the deck from the water, as I would on my former Sunny or my packraft. But the K40 bobs quite high when empty, so I was surprised I managed it, perhaps aided by the added buoyancy of my dry suit.

The problem is, once slumped belly down over the hatch (above), what next? You fall back in, that’s what next, because trying to turn onto your back tips you off long before you get your legs securely down the hatch. Perhaps with a bit more practice and finesse it could be done, but this was pretty calm water so realistically, just as on a hardshell sea kayak, it’s usually too tricky to pull off unaided. I then tried with my new paddle float as an outrigger. Would you believe it, re-entry was much easier and also pulls less water in as the boat remains more upright. Hook a leg over the floating paddle shaft and scuttle aboard. From this position I found it was fairly easy to flip round and drop bum first into the hatch and then stuff the legs in. 

On that day I was carrying my two Watershed dry bags full of camping gear to see how it handled, so they helped reduce the boat’s possible swamped water volume, but even then any deckless IK conveniently self-drains when flipped back over – no awkward, X-rescue hauling over another kayak’s glossy fibreglass deck to drain. Once in the K40, there were only a few inches of water to bilge out, certainly not enough to cause sloshing instability (the true reason why you need to drain a kayak fast following a deepwater re-entry – not because you’ll get your pants wet).
One thing I noticed was a rope knife attached to my pfd got caught on the hatch coaming, and also all this grovelling around over my wet kayak’s deck pulled the bite valve off my new CamelBak/pfd set up which then drained away. That will be £4.99 please. Now I know to reposition one and tuck in the other to avoid any snags.
Spraydeck newsflash! The massively oversize cheapo spray deck I bought and modified (left) still required a lot of scrunching. But having actually used it, my feeling is the K40 sits so high it’s not going to be needed unless it gets cold or I’m heading for river rapids. At other times it’s just more clobber to carry around, wash and dry. Maybe I’ll get to see the value of it as my experience in the Incept extends. On a much lower sea kayak like Jon’s P&H, a deck is pretty essential.

The other way to get back into an Incept from deep water would be to simply unzip the decks and haul yourself on. No paddle float needed, although it occurred to me yet another use of the Watershed bags, particularly the smaller yellow Chattooga, could be as a paddle float (left). Any dry bag will do, but you know the Watershed’s won’t so much as seep a drop like a roll-top will after a few minutes, and the Chattooga even has some clips which can be used to secure a paddle blade.

If not using any type of outrigger float, a bit more water will swill into the K40 as you pull over the side to get back in. Ideally you then want to crawl up through the unzipped hatch hole as you got aboard, ease around and take your seat. But now you have the fairly tricky manoeuvre of trying to zip up the decks, all while hanging onto your paddle and not tipping back in. As I found first time out, without the support of another boat or a float, reaching the fully opened zip pulls on the Tasman is quite an unstable stretch from the seat, even with the grab loops I’ve tied to them. Longer loops might get in the way so some sort of a hook stick is needed if no one is around to do it for you. Regarding the K40’s zippy deck, as long as I wear a dry suit I can see even less need for it at sea in the conditions I’m every likely to go out in. Only on a WW 2 or 3 river would it be handy (with the spray deck) to save the boat swamping and the need to find a bank to drain it.
If you’re paddling undecked, getting in from deep water all so much simpler, just like an SoT, and if not there’s a good section on the informative Kayarchy website illustrating all sorts of deep-water rescues.

Next day we set off to try and actually paddle somewhere, but off the beach it still looked horrible (left and right); 15-20mph winds but now from the SW. We paddled towards the Isles anyway, but after 15 minutes I didn’t like what I’d guess you’d call a boat-stalling ‘short chop’ which would only get worse further out. While hacking away warily, it occurred to me that focussed as you are in such conditions, it takes some effort to think of others or even keep track of them, and should they flip while you’re barely coping yourself, it can all go horribly Pete Tong. After all, no one usually capsizes is calm, wind-free conditions. That’s why we wanted to get some practice time together out here. The plan had been to go as far as camp the previous night, but the miserable weather and a fully fitted house just a mile away nixed that idea.

It wasn’t actually that gnarly, just not much fun and possibly about to get less so. As we did a U-ey I was encouraged to observe my Incept that morning felt less intimidating to turn than Jon’s slinky P&H. Again, no great surprise; his boat is floating stick insect with the turning circle of a stretched limo. The K40 is wide, has a rudder and – now that I’ve seen pics of me in it – the ends sit out of the water even with my weight and a 10-15 kilo load aboard. Is that a lot of ‘rocker’  or a little, I forget, but it turns easily with rudder + paddle strokes, and with the rudder up can spin on its axis with a lot fewer paddle strokes than Jon’s Scorpio. And with fewer edgy moments too. I was getting the feel for the Incept in rougher water.

So we sailed ourselves back to the beach, fighting to steer with the tailwind. Once there we settled for messing about closer to the shore, practising more turns out on the swell or paddling parallel to waves to gauge tippiness, secure in the fact that we were constantly getting blown inshore.

I was open deck that day, but noticed where the Sunny would have flexed and swamped over the rounded sides where I sat, the more rigid and higher-sided K40 stayed mostly dry. I was also conscious that even though they are also more clobber and something to catch your foot on, the thigh straps I’m waiting to glue in would surely help control in rough water. Either that or I see them as the only possible explanation for my lame kayaking skills! With the deck off we also tried paddling the Incept two-up – me sitting in the back facing backwards. That’s a total weight of at least 180kg in our gear, 20kg over what the Tasman is rated for. Jon reported the boat was tippier like this and had it been a serious requirement, I could have laid down to improve stability.
One thing I noticed open deck is that there’s less back support from the low seat – a common problem with IKs using inflatable seats, and one reason I went for a Aire Cheetah seat on my Sunny. Clearly with the deck on the flexible coaming helps as a back rest and by the end of that day I felt the tops of my legs straining a bit in a bid to maintain upright. The problem is there is nothing solid to brace the feet against either, but I imagine this is another benefit of fitting thigh straps.

Having mastered many new skills, we had a quick scoot in the packraft (above); fun and very stable in the conditions, but also so slow you’d run out of puff before getting anywhere. The initial instinct in the chop was to try and jump it like a BMX bike; it sure would be fun to try surfing it on bigger waves one time.

Suddenly a glassy calm befell the bay, just as a private weather station near Ullapool recorded accurately in the graph on the right. Great we thought, let’s make a dash to the Tanera Mor about a mile and a half away, so we can say we got off the mainland – an ‘open water’ crossing! In this way many foolhardy newbs sail off to their doom, I suspect, because little did we know it was just the wind clearing its throat and refilling its lungs before coming back from new direction and harder than ever. But not before we’d managed to cross over and nudge the island’s sandstone cliffs (left) with our bows.

The previous day and that morning I’d been put off in similar- or even easier conditions but now, after a few hours playing around we were more tuned into our boats and even headed back diagonally across the stiff back wind and swell to make it a bit more difficult. Me of course with the aid of my rudder; without it I’d be correcting all over the place and need to stern-rudder, as Jon occasionally did. With backwind ruddering, I noticed it’s not a simple matter of holding the rudder at a certain angle because the tracking continually goes off, presumably as a quartering wave rises and drops behind you. A constant pedalling of the rudder controls was required to keep on the track. Don’t know if that’s normal, but I’d hate to wear out my rudder lines prematurely.
So not a totally wasted weekend. Now we know we can get back into our boats alone one way or another, and can actually handle F4 conditions within sight of the shore, even if next time we go out, initially we may not feel that way.