Can a rudder produce a strong turning force on a sea kayak; other wave-fighting recommendations?

Discussion in 'Boat Design' started by mitchgrunes, Jun 18, 2021.

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  1. mitchgrunes
    Joined: Jul 2020
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    mitchgrunes Senior Member

    Does a rudder only provide a slight turning force that helps a little, or can it provide a strong turning force comparable to the strongest control strokes, so that I can go back to two bladed paddling under difficult conditions without much lean?

    A few days ago I had a lot of trouble controlling my (Current Designs Caribou) sea kayak, which has no rudder or skeg, in mild shore break. It was a trip in Cayuga Lake (a glacial "finger lake" in upstate NY), which is normally quite benign - it's long and thin, in a valley, essentially no tides, no big ocean waves, with a long fetch in only one direction. As I started my paddle, a minor unpredicted storm (no lightning) blew in.

    BTW, I have relatively little experience paddling into shore break. It scares me, and I generally won't go out in it. But the waves were only about 1 foot (30 cm) high, though they eventually reached 2 - 3 feet (60-90 cm) high, so I thought it safe.

    I was paddling from shore, in shallow water, with fairly steep 45 degree angle wind waves, more or less shore break. The waves kept pushing me to turn, in the direction the waves were more or less breaking, sweeping me across the beach. The main force was definitely from the waves, not the wind. (Wind alone mostly doesn't tend to turn that boat with me in it. I set up my kayaks with neutral trim with respect to beam winds. I hate boats that weathercock significantly, but apparently this boat lee-cocks in waves of that height, which I think is even worse. I did not realize that the turning response to steep waves could be so different from the response to winds.)

    On other occasions in wind and waves, I have found it sufficient to tilt the boat towards the forced turn, and to hold the paddle off-center. Then I can fight the turn without much effort or otherwise altering my stroke. But on this occasion, that was completely insufficient.

    Draws on one side and sweep on the other also weren't sufficient to compensate.

    Forward/sweep paddling on the side it was turning to, and back paddling on the opposite side, was also insufficient, and of course made little headway.

    I'm out of practice, and forgot to apply the turning force strongest on top of the wave. Perhaps that would have helped a bit. But the fundamental problem was that the boat turned while the paddle was out of the water, while I switched paddling sides, and/or brought the paddle forwards.

    I recall reading somewhere that it is sometimes easier to let the waves turn you all the way around (nearly 360 degrees) instead of fighting a turn, but I have never practiced that, and it did not occur to me. I have not needed it before.

    Incidentally, I was using a lightweight Epic wing paddle, set unfeathered - interesting how much it blew around in the wind. I wonder if that is a generic characteristic of wing paddles? I had my Greenland paddle too, but by the time I realized the problem, the waves were too steep and the water still too shallow to comfortably switch. In any event, that wasn't the main problem.

    I was taught in whitewater a canoe-like technique that is sufficient to control a boat under difficult conditions (it helps that whitewater boats are easy to turn), because the paddle stays in the water, on the side you want to turn towards, and in control of the boat all the time. The technique is a strongly leaned on-side C-stroke, followed by a "feather" to cause the paddle to slice through the water, while you bring the paddle forward again on an outward arc through the water, essentially creating a circular stroke, which continually draws you towards that side. This stroke can often fight forced turns. But that is a highly asymmetric and inefficient use of the body, and would probably therefore make me sore during a long sea kayak paddle. Perhaps I could have experimented more with this stroke, but I was paddling solo, and curtailed my trip instead, out of safety concerns. (I've always been a coward.)

    (It just occurred to me: perhaps an offside lean, using an inverted C-stroke that was closest to the boat in the center rather than the ends, followed by an inward feathered return stroke, would work better in a displacement hull sea kayak? I haven't tried that. But I hate offside leans under difficult to control situations. And it would still be a highly asymmetric and inefficient use of the body.)

    The boat was designed for people bigger and heavier than me. On flat water, I lose a few feet of waterline at each end due to rocker and light weighting, though the waves were high enough on this occasion to turn the boat from the ends. As a result, as well as its relatively high volume ends, at that wave height, the boat pitch goes into resonance with the waves, and the bow bounces up and down, which hurts control and speed, a lot. That didn't help.

    In short, several contributing factors made control difficult.

    I have another boat with lower volume that I have controlled much less trouble in 6' - 6.5' wind waves (though they mostly weren't breaking waves), but I cannot re-enter that boat while at sea without flooding it to some extent, because the deck is too low and the cockpit too small (it was designed as a competitive SOF Greenland rolling boat, totally impractical), so it is a roll-or-die boat - the only at-sea re-entry I can do in it is a re-enter and roll; I don't know if I could do that under difficult conditions, and it would take a long while to pump out. While that boat is faster and lighter, much more fun to paddle, and far easier to control, I feel the difficult re-entry makes it unsafe.

    I intend that my next boat will have lower volume ends and a full length waterline, a bit like Epic racing kayaks, but a bit more stable. I am in the early stages of experimenting with a home-made prototype, to try to understand what works for me, but haven't gotten very far yet. In any event, being a coward, I would not take a fragile prototype, built from PVC pipe, duct tape, and a tarp, into difficult conditions.

    In the meantime, I am trying to decide whether a rudder or skeg would help much in similar situations. I have never owned a boat with a rudder or skeg - partly because I have often seen ones that need repairs, and would worry that the rudder or skeg would fail under precisely the conditions where I needed it most, and be locked in a configuration that made control impossible, like the Bismarck. Besides, I love and need lightweight boats.

    Do any of you have experience that would help me decide whether a rudder or skeg can provide an amount of control comparable to and/or significantly augment strong control strokes?

    I once tried an Epic 18 surf ski with a rudder. The rudder turned it well. But that test was at very low speed in almost flat water, and I was fighting too hard for stability to try it at higher speed or in waves.

    BTW, any other ideas about how to handle conditions like those I encountered? E.g., other stroke techniques?
     
  2. cthippo
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    cthippo Senior Member

    I have never paddled a kayak that had a lot of rudder authority. Mostly the rudder is good for slight course corrections to maintain a heading and for large course corrections you heel the boat and paddle on one side. A long boat especially is just not going to change direction fast, no matter what. A skeg is nice, but in a following sea you are just going to ride the struggle bus all the way home. In those conditions I actually prefer a shorter (10' or so) boat for it's responsiveness over the straight-line speed of a long boat. My favorite dynamic water (including surf) boat is an 8' Pyrahna Everest which has a flat bottom and will not go in a straight line for anything, but will turn a full 360 on a single paddle stroke.

    My rule for dynamic water is 1. Stay upright 2. Everything else.
     
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  3. Kayakmarathon
    Joined: Sep 2014
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    Kayakmarathon Junior Member

    I've paddled Cayuga Lake, Epic paddle, and 17' sea kayak without a rudder.

    The swept up bow, bow overhang, and relatively flat aft deck definitely contribute to lee-cocking. The deck is like a sail with its center of area/effort well forward of midship AT ALL TIMES. As the boat pitches up, that sail area gets even bigger and farther forward. This is more lever than a sweep stroke can counter. At the crest of the wave both ends are out of the water, so an over the stern rudder will most likely not be very effective. The kayak was not designed for these conditions.

    A 14 or 15 foot kayak without a swept bow would handle better. It is difficult to find a touring kayak without a swept up bow since most manufacturers offer Greenland style. Epic Kayaks offers the "14X". I have a shorter Epic GPX that I have no problem handling in very rough conditions. Double gold sprint kayak medalist Greg Barton has blended the speed aspects that he learned from paddling Olympic kayaks with recreational/fitness kayaks for optimal hulls.
     
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  4. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    The short answer to your question is that a rudder can certainly address your wind and wave handling problems and is a much better solution than the the stressful strokes, edging, and overhangs of your current setup. I second the advice to get a smaller kayak with a similar waterline length and a smaller beam (since you are obviously comfortable with narrow boats like your roller). Your CD boat is a freighter unless you are very large and strong. To turn it you must get the ends out of the water, timing your stroke, side and position to the waves. This obviously is a waste of energy and forward thrust. I don't know what to make of your rudder reliability concern because I would not buy a kayak from a company that could not design a reliable kick-up rudder.

    The long answer is unflattering to your current setup and likely goes against what you were told and taught by a salesman/woman. As such I will withhold my "rant" unless you want to hear it.
     
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  5. mitchgrunes
    Joined: Jul 2020
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    mitchgrunes Senior Member

    I fully accept that neither of my boats, designed for people of different size and weight than me, are ideal for me. I've had a fair number of kayaks over the years. Each has had good features and bad. I don't blame sales people - I made my own decisions, and I bought the current ones used from private parties. I seem to end up having to learn from mistakes. The sea kayak I had before was worse - it had very high bow and stern, that blew around in the wind all the time. And for a while I tried to use a 1970's era whitewater slalom boat (Phoenix Cascade) as a sea kayak, that rocked enough to make me seasick under the wrong conditions, and that was fairly slow.

    An 8' boat would not meet my needs. I don't seek out serious surfing spots, of the sort that surfboards or surf boats play in, unless you count low level whitewater, for which I have another boat. Most of the time, I struggle to keep up with stronger paddlers at 3-4 knots or so, so I need something with relatively little resistance at those speeds. But I don't race either, so Greg Barton's boats, and similar, aren't really what I am looking for.- I need a compromise. And I need a boat I can lift, which I is why I am exploring the custom SOF option.

    Part of the issue with Lake Cayuga, and the area around Ithaca, is that weather is unpredictable. E.g., I went out when sunny weather was predicted all over Cayuga, but by the time I unloaded my boat, a storm had blown in. After I loaded my boat on my car again, it got sunny again, but I'd had enough, and had a schedule to meet. Mark Rust has songs about Ithaca weather - he says that if you don't like the weather, wait 5 minutes. :)

    I need something to handle all plausible sea kayak conditions that I might meet, not a special purpose boat that will only work well for part of a trip.

    I'm puzzled that one of the respondents says that rudders only do a little, and the other says they do a lot. :) Perhaps different types of rudder have different effectiveness? If I do design my own SOF toy, maybe I need to understand that better.
     
  6. upchurchmr
    Joined: Feb 2011
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    upchurchmr Senior Member

    If a rudder only does a little, it is entirely possible to upsize the rudder blade to get more control.
    Also a little bit more drag, but you probably couldn't tell how much.
    When adding sails to a kayak or canoe the rudder gets much bigger.
    Check out the CLC Sail Rig kit.
     
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  7. KJL38
    Joined: Jun 2008
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    KJL38 Junior Member

    Am I understanding correctly that you were paddling into the waves at a 45 degree angle? If this is the case the wave reaches the front half of the kayak first and pushes it sideways which makes it sit along the trough of the wave. A rudder will help by allowing you to turn into the wave as it hits but whether it is enough depends on a number of things, especially your speed. An alternative approach is to paddle directly into the waves for a while and then turn 90 degrees and go across, on the return paddling with the waves at 45 degrees is easier as the waves reach you less frequently and you may be able to surf them.
     
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  8. Skyak
    Joined: Jul 2012
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    Skyak Senior Member

    A rudder is definitely the answer to cross wind and wave tracking problems. If it doesn't work it's not in the water, you aren't moving, or it is way too small. You will not turn as quickly with a rudder as you can with a good edge and sweep stroke, but that is because you still have the full length of the boat in the water. With the rudder you have a continuous moment setting your track and your entire body free to paddle efficiently. With the sweep stroke you are loosing the efficiency of the double paddle and wearing out one side of your body.
    Your wing paddle makes no sense without a rudder. The gain from the profile is lost on the tail of your kayak pushing side to side.
    For 4 knots easy you need a 14ft waterline, a rudder, and as narrow a beam as you are comfortable with. If you sit low 18 or 19" waterline beam is comfortable. How wide is your roller?

    Who said a rudder doesn't work? Cthippo said he prefers shorter whitewater boats for rougher conditions. That's play, not travel to a destination.
     
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  9. Squidly-Diddly
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    Squidly-Diddly Senior Member

    IMO kayak rudders are a bit too big and offer more than enough extra control, but I don't go out in rough stuff and only play around with SOT.

    But, yeah, adding a typical rudder should make a world of diff in tracking and quite a bit of roll damping. Will be a bit distracting trying to keep it straight for vigious paddling and unless you are shooting rapids or playing in big wave rock gardens a rudder will offer LOTS of turning, far more than needed.

    SO....given options during setup, go for min amount of rudder turning per max amount of foot motion. You don't want a twitchy rudder.

    Prob with rudders is they create bit of drag, enough that you'd want to rise them if not needed, then the raised rudder seems to catch slightest breezes and push you off course.
     
  10. BlueBell
    Joined: May 2017
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    BlueBell . . . . .

    What do you mean?
    Beam?
     
  11. mitchgrunes
    Joined: Jul 2020
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    mitchgrunes Senior Member

    With the style of paddle control I use (0 hand control - i.e., control the path of the paddle, let hydrodynamics orient the paddle), I normally notice no difference in efficiency or rollability between wing, euro, and greenland paddles, nor does feather angle matter much, unless it is extreme. only weight matters.

    My lightest paddle happens to be a an adjustable feather Epic wing paddle. So it's what I normally use - except that mine isn't long enough to do offside bow draws, unless I extend it a lot. My Greenland is a little longer. Of course that may be partly because none of my current sea kayak paddles were originally sized for me - when Alison Segithy upgraded to a future year's models, I bought 4 of hers - 1 wing, 1 Euro, 1 offset; she has somewhat narrower shoulders than me. :)

    But in the higher winds, the wing paddle tended to blow all over the place. Perhaps it would have helped if I set it to non-zero feather...
     
  12. Kayakmarathon
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    Kayakmarathon Junior Member

    Using a cross draw stroke is asking for trouble. It is a precariously unstable position that requires quite a bit of flexibility. You can capsize or really hurt your shoulder/back. Use a sweep stroke on the other side instead.
     
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  13. mitchgrunes
    Joined: Jul 2020
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    mitchgrunes Senior Member

    The 0-hand control technique (my term) makes it less extreme, because you don't have to roll the arm in the shoulder joint to adjust the paddle angle. I don't understand why 0-hand control isn't common. It allows full length strokes; it seems much easier on the body, because it helps the shoulder stay low and the arm doesn't have to roll out of the socket to take more extreme paddle positions; it simplifies rolls (especially with scooped paddles, and extra-specially wing paddles), and it allows full length stroke boat stabilization and control, when the paddle is far ahead of or somewhat behind you. I can't figure out why single or double hand control would have much benefit.

    But for me, even with 0-hand control, a cross draw is indeed always at the limits of my flexibility. I sometimes do it in flatwater, to stretch my muscles, but would hesitate to use it in significant waves or currents, or at full speed, because it pulls pretty hard on my shoulder.

    I often wish I had that kind of flexibility - though I realize people with extreme flexibility have other potential problems.

    Cross draws seem to be a somewhat common canoe technique - perhaps the higher position makes it easier or safer? Are they common on SUPs too?

    Of course, on very short whitewater craft - and perhaps on super short surf boats too?? - it seems now somewhat common to start draws slightly crossed, and continue the stroke in front of the boat into an onside sweep. I guess that is one of the cool features of boats that are only marginally longer than inner tubes. :) Unfortunately, I wouldn't be able to keep up with strong sea kayakers in an inner tube.

    But I wasn't talking about a cross draw - just an onside bow draw with an offside lean. As I'm sure you know, the usual specification is that you start with an onside sweep, and switch to the other side for an offside draw, which turns much more effectively than offside sweeps alone.

    I've thought about what you said about the bow of the boat acting like a sail if it bounces too high. That makes a lot of sense, though I still think it is mostly water pressure from the waves that created the problem. I suppose extremely low volume ends have a different problem - I used to have an early Wavesport XXX which went unintentionally vertical even when I just wanted to paddle through a hole. I haven't had that problem in sea kayaks - perhaps because I have avoided the high wave conditions that cause pitch poling - but the high volume ends of every sea kayak I've had but the roller are clearly problematic even at modest waveheights. I think Epic got that part right, even for non-racers. (I haven't had much chance to try other brand racing kayaks, other than a rounded hull boat that was nearly as unstable as a log.)

    Perhaps high ends help keep sea spray and splash - and jellyfish with them - out of the eyes, and overhang makes it easier on the boat to land it, especially on fragile SOFs, but I don't see either as worth the loss of control and extra weight they entail.
     
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