Let's talk rudders

Roy

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Jun 2, 2007
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150
Location
West Vancouver
From Old Sailor - "There are only a few kayaks with hulls that need neither rudders nor skegs; and I'm lucky enough to own three of the models Mariner has made over the years"

I'm with you there. I've owned several Mariners, currently have a Mariner II. Great boats and they behave very well without rudders (or bulkheads, or hatches). OTOH I'm no longer evangelical about these "advantages" because everyone is different and has different needs. Regardless, practice is the key to becoming comfortable and competent with whatever you paddle.
 

mick_allen

Paddler & Moderator
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May 15, 2005
Messages
3,267
mick_allen wrote:
...under hull location(s) so always in water in waves etc, and underhull retraction so no windage...
Is there such an animal Mick?
I call such an animal the ‘slot rudder’. For us designers, the slot-rudder is the holy grail that has been continually searched for with many funny and wierd results - there are many fits and starts and half attempts and false attempts and goofy attempts and possible realizations.

Here are some of the steps by others along the way:


integrated rudders
So called as they supposedly integrate with the hull lines and when unused, do not add any extra drag to the hull other than the hull itself. Unfortunately the rudder is always exposed, the hull requires either zero rocker for the rudder to be effective in any way and as they are so ineffectual they tend to develop little extra blobs on the bottom or side. The less developed of these cases also expose the rudder horns, cables and fittings:
some examples:

mirage:

more info at
http://www.mirageseakayaks.com.au/product_rudder.html

epic kayaks 18x sport:



more info at
http://www.epickayaks.com/products/details.aspx?nid=663&cid=3371


illusional slot rudders

These are rudders that give the illusion of retracting into a slot in the hull – but only if viewed from a distance and directly from the side. Upon further inspection, one sees that there is in fact a large pie shaped or larger depression in the hull that the ‘rudder’ can ‘hide’ away in no matter what angle it is deployed at . And in this ‘retracted’ position, the rudder and its depression still are a depressing drag. And as with the
‘integrated’ rudder above, the less developed instances also expose (and immerse) cables and joints and fittings.

Some examples:
Extreme Interface:

more info at
http://www.lightspeedkayaks.com/about_rudder.html

another self design version from a guy down under, also with the obligatory large pie shaped bottom hole.
(editor: links and jpg lost)

Pietsch
Also has the usual big hole or depression in the bottom. And as the rudder ‘post’ itself has to move, likely a little more play has to come into effect than otherwise expected (this is a surmise). I doubt that the receiver can be in constant contact with the post – an extra failure mode or sideplay circumstance.

more info at
http://www.pietsch-hansen-kajaks.de/steueranlage.htm

delusional slot rudder

lettman – hard to really see in the pdf but something like a slotrudder is shown. Deploy lines hidden, I think - but don’t understand quite what’s going on – it seems incomplete. Doesn’t appear to be any realignment mechanism, so must be some kind of indicator if in alignment so then can retract. Either it or I am having delusions here.
info on the pdf file at
http://www.lettmann.de/archiv/service/LMKatalog2005K367.pdf
[ed. - link is lost, but here is the view]



goofy slot rudder

zolzer has a funny flex scoop rudder with exposed lines running down each side of the blade. The exposed line must make it quite draggy and as the ‘rudder’ probably curves to deploy, not very effective. This is one of those ideas that should have been worked on a little more in the sketchbook.



more info at:
the zolzer website

a possible real slot rudder:

Geof Turner at Kari-tek has come up with what might be the first real commercial slot rudder. Unfortunately, the resolution is extremely cumbersome with housings within housings – so one gets a wide slot with a bulky skeg box, multiple hydraulic lines and cylinders, and inside awkward moving parts on top of the skeg and at the footpeg. However, he undoubtedly has a solution to at least one fundamental part of the slot rudder conundrum – the auto realign retraction. There is not enough info that i/ve seen to assess how well other aspects of the slot rudder are achieved, but this approach seems is a major step in the right direction.

sideview:


parts view

more info at:
http://www.kari-tek.co.uk

..

For me, ‘slot rudders’ should meet the following criteria:

  • - completely internal rudder assembly with only a slot in the bottom of the hull
    - absolutely no extra required hull or keel protruberances so hull can be as rockered or smooth or shaped as desired for any other reasons than the rudder.
    - absolutely no exposed lines or cables or rods or attachment points either below or on top of the yak to catch or cut or interfere or tangle.
    - not necessary, but say can deploy to as much as 45deg ea side
    - slim slot flush to bottom of hull, only as wide as the rudder blade (clearance added only if desired for anticipated sand/gravel jamming conditions – I would choose minimal clearance and possibly mount rudder 1- 2” off keelside- be interesting to test)
    - an automatic self aligning mechanism for the rudder blade to automatically and instantly insert into the slim hull slot. Will auto align and deflect if hit by moderate sea obstructions or by the user quickly panic ramming the rudder up with no thought to how the rudder is deployed when initiating . This is a complex mechanism and I would accept that big impacts or side impacts will cause the same damage as if a skeg.
    -as this alignment mechanism is so fundamental – say some redundancy to ensure realignment on retract.
    - the internal rudder steering mechanism should be in constant engagement for minimized sideplay, minimized jamming, and minimized failure.
    - the internal mechanism not much bulkier or heavier than a typical skegbox with an additional steering yoke and lines or cables or rods.
    - design refinements to minimize weed contamination of the rudder axis in the deployed mode. (but no protruberance on retract)
    - options of typical fully articulated rudders or the more stronger true skeg rudders (where the trailing edge of the skeg articulates – like the rudder of an airplane). Both operate and retract similarly. (these are not necessarily interchangeable options)
    - options for high or low aspect depending on the duty expected. (these are not necessarily interchangeable options)
    - apply to most hulls by just cutting slot and gluing in the box .
    - allow typical skeg deploy knob with any type of rudder pedals or foot deploy, retract and steering - self adjust.
    -the potential for making very small, light (and likely fragile unless exotics mat’ls) for racing application.

We are in the times in which the above specifications are beginning to be realized - the holy grail is almost at hand and is certainly within reach.


-mick
 

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SheilaP

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Jun 6, 2007
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Victoria, BC
WOW! Mick the rudder pro. Thanks for the pictures and information! :shock:

So I must be chicken and old :p :p :p - I use my rudder a lot. Yes, I practice without, but I don't enjoy a paddle the same way when I am constantly correcting. Besides it makes my old back hurt after a few hours. And, like Kasey, I find I ram into people when I chat without it. I tend to be yakky sometimes: just ask Elmo. :wink:

I do have the Nimbus Telkwa HV; it doesn't track that well IMHO. It is big and prone to the wind and the rocker leaves little boat in the water. But I like this boat because it is fast, nimble and it holds 410 litres of gear! (And paddles better full.)

I do long paddles most of the time. I hate getting onto the water for anything less than four hours and tend to do multi-day trips. I have ordered the spare parts kit for my boat which includes all the rudder cables. If my rudder fails, the seas are that snarky and my skills fail me, I can always hitch a tow to help keep me in line. 8) 8)

Now if I had gone with the GT Solstice I may be saying something entirely different in this forum! :wink:
 

elmo

Paddler
Joined
Dec 28, 2007
Messages
650
Location
Victoria BC
Great information Mick :)

You obviously put a lot of thought into your answer and I appreciate that.

I'm going to mull this around for awhile and then I'll post any thoughts and questions that I have. Would really be interested in pursuing this subject.

Do you happen to have any favourite links to a website that introduces the layman to hydro/fluid dynamics. I assume these are the proper terms? I've a friend who is quite an aviation buff. He might be able to give me some help as I assume fluids behave as fluids whether water or air. The aviation industry seems to be a forerunner in these technologies, I guess 'big money' drives research.

Things are starting to come together and make sense to me now :)

Really interesting stuff...

daniel
 

nootka

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Joined
May 26, 2007
Messages
1,592
Location
Campbell River
Mick's post causes this page to have a horizontal scrollbar, which is a nuisance. Here is how to post a URL such that you see a label and not the url:

(1) type or paste in the url ie http://www3.telus.net/adunham/sitka3.jpg
(2) highlight the whole url
(3) click the URL button (above upload picture)
(4) change the right bracket in to an = (5) insert ]SITKA before the ... (where SITKA is your desired label)
(6) you end up with {url=http://www3.telus.net/adunham/sitka3.jpg}SITKA{/url} ... except the curly brackets will be square brackets
(7) test it with preview

SITKA
 

Dan_Millsip

Paddler
Joined
Mar 8, 2005
Messages
9,325
Location
Beautiful BC
nootka said:
Mick's post causes this page to have a horizontal scrollbar, which is a nuisance.
Sounds like you need a bigger monitor. :wink:

I've corrected Mick's post -- thanks though, for the info about posting linked text -- you're right, it is annoying to have to scroll sideways. 20 lashes for Mick.

Back to rudders...

*****
 

lance_randy

Paddler
Joined
May 17, 2006
Messages
571
Location
Victoria
I don't know so much about rudders, but I find I use the skeg in my Nordkapp LV a fair bit when doing crossings. I find that without the skeg, it tends to weathercock in even light wind, and it's a pain in the butt (literaly) to paddle with the boat on edge for anything more than a minute or so.
With my Greenlander Pro however, I rarely reach for the skeg.
I used to avoid using the skeg at all costs, but now, I don't see the point in being a hero. I use it to trim the boat, and that's about it. I'm curious how other people use their skegs, do you avoid them, feel guilty using them, or embrace them?
 

andreas

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Joined
Jul 1, 2005
Messages
1,163
Location
Victoria BC
As you said, sometimes it's just easier to drop it and you don't have to worry about using correcting strokes. BTW, I don't care if it looks cool or not and what other people think about it, if dropping the skeg makes my paddle more enjoyable, I do it.
 

SpaceCowboy

Paddler
Joined
Apr 5, 2007
Messages
90
I bought a looksha IV last year. I chose a rudder, because I planned to use it for expedition length trips, and thought that the little extra flexibility it gives vs. a skeg would be appreciated when the time came.

As it happens, from the factory, the rudder cables are about 14" too long, when the peddles are fully extended there is about 8" of spare wire slopping about. So, over more than a dozen day-trips, I have never even unstrapped the rudder. I do notice a bit of windcocking, and until this thread, didn't dawn on me that having a rudder up would exacerbate that (duh!) any rate. as I have never used it on this boat, I will shorten the cables this week,and let you know what (if anything) I notice next weekend.

Cheers.

G.
 

mikec

Paddler
Joined
Aug 3, 2006
Messages
601
Location
Sept-Îles, QC
i don't use my skeg at all, in fact, on my new Romany I actually ordered it skeg-less. i just use paddle strokes and weight shifts to keep my boat going where i want it to go. all depends on your boat though.
 

mikec

Paddler
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Aug 3, 2006
Messages
601
Location
Sept-Îles, QC
caveat - i don't mind doing a little extra work now, though talk to me again in 20 years and perhaps i will have changed my school of thought on that!
 

Jurfie

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Joined
May 6, 2007
Messages
843
Location
Semiahmoo, South Surrey, BC
The more I paddle (I started only last year), the more I think I'd prefer a skeg boat. I have nothing against rudders (whatever makes your experience more enjoyable, go for it), but I find that moving my feet back and forth causes them to fall asleep. I have long legs, so it's a tight squeeze for me anyways...the past couple of times I've gone out, I've ended up putting the rudder up and used strokes to keep straight/turn.

In my (limited, granted) experience, and in rental boats, at least, I've found the footpeg straps get sloppy when the rudder is deployed. Locked with the rudder up and the boat is more comfortable.
 

blondie

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Joined
May 29, 2005
Messages
269
Location
Nanaimo
I do like rudders (and similarly skegs) for their ability to help with tracking. Some boats and conditions will need more or less help. Sometimes I will use a rudder to be able to better keep up with faster paddlers.

The boats we rented in New Zealand were absolute barges, and loaded they were quite sluggish at reacting to corrective strokes. I tried for some time to manage without deploying the rudder. It wasn't impossible, but it slowed me down quite a bit. :( So I put the rudder down, and a few minutes later 'ping' the bolt attaching the cable to the rudder is making its way to the bottom of the sea. :shock: Okay, fine, the loss of the rudder I can deal with. The loss of the use of the foot petal, not so much. Suddenly not being able to brace, or really even edge was definitely an issue.

Granted, once ashore, we fixed it up with a zip tie (which snapped an hour later) and then a carabiner. Not so happy with rudders that day.

So as I see it, rudders and their associated 'sloppy' pedals aren't really so hot for bracing and edging.
 

Mark_Schilling

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Mar 8, 2005
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"Home by the Sea" - Nanaimo, BC
blondie said:
Not so happy with rudders...

So as I see it, rudders and their associated 'sloppy' pedals aren't really so hot for bracing and edging.
Does that mean we've succeeded in converting you to skeg boats? :lol:

Paddling the 'barge' (a New Zealand made Puffin), I was having similar problems keeping the foot pedals where I wanted them (although I did have better luck with my cables - one was badly frayed but managed to remain intact for the duration of our 3-day voyage). The boat was weathercocking badly, despite being loaded heavy in the stern, so I 'gave up' and deployed the rudder. :shock: I then realized that, after paddling for a few years now, I've never actually used a rudder in a single kayak. :eek: I have to admit, it actually worked quite well! But keeping it straight meant that attempting to turn the boat the 'normal' way (ie edging and strokes) was much less effective, so I had to use the rudder to assist in turning the boat. So, while it did work well and allowed me to keep up with Blondie, I can easily see how it could really slow ones progress on the road to becoming a more skilled paddler.

Paddling the boat empty the next day, and using the spare paddle to help secure the rudder to the rear deck (without allowing it to flop around), I found that even though the boat was far from responsive, it actually handled quite well and let me play around in rocky areas with some degree of confidence. So long as I wasn't in a hurry to do anything.

It'll be a treat to get back in the Explorer again - as much as I enjoyed the Puffin, I'm not trading in the Explorer any time soon. I should also note that the only kayak I saw that wasn't a cheap NZ-make plastic rental boat was an Explorer, pulled up on the beach on Stewart Island. I was tempted to take it for a spin... but we had Kiwis to search for on the Raikura Track, a brutal 3-day tramping (backpacking) excursion. It, too, made me appreciate sea kayaking that much more. :oops:
 

Astoriadave

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May 31, 2005
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Astoria, Oregon, USA
Sounds to me like the outfitter needs to do some maintenance on those Puffins, you two! Been paddling my Wind Dancer for 15 seasons, all involving heavy rudder use, and replaced cables 10 years ago just because I did not know how fast they wear. The cables I pulled looked good as new with a little wear, so the ones in there now should last another 5 years.

I do not understand how cable failures can vary so much.
 

Greg

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Apr 17, 2006
Messages
113
I have a CD Sirocco (17' x 23") that has a skeg and I feel like I have to use it all the time or else my boat is swishing left and right if I don't use it. I've had my boat for a year and so far have only used it for day paddles so it has never been loaded down with much weight except for me.

I know all boats are different but do you guys think that your boats track better when they are loaded or when they are empty? I'm thinking my boat would probably track better loaded since it would be farther down in the water and the keel would have more tracking effectiveness and also would be less susceptible to weather cocking.

I'm thinking of trying some loaded boat paddles to see if it makes a difference since I'm planning a river trip next fall and the boat will be loaded to the brim on that trip.

I thought I would just get some input from the tripping experts around here first :)

Thanks,
Greg
 

Astoriadave

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May 31, 2005
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Astoria, Oregon, USA
Greg, each design has an optimal waterline position (in theory), such that handling does change with load. Usually, the manufacturer gives you a hint at that when they tell you the wieght of paddler the boat is designed for.

The change in performance has more to do with the change in hull shape underwater than the depth of the keel, but I'm not the guy to pontificate on stuff like this. Some of the more sophisticated folks here can give you a better answer.

In the end, however, it is all trial and error, once you own the boat. I know my main hardshell is a skittish colt with just my 220 lbs in it, but loaded for a week, it is a solid, graceful performer ... sort of a "hippo in the Nile" critter, I guess. :lol:

Cleopatra would have loved my boat. Marc Antony, maybe not so much. :wink: :twisted:
 

mick_allen

Paddler & Moderator
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May 15, 2005
Messages
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boats won't become better trackers if they are more loaded than not - it depends on where they are loaded as well as the underwater shape as mentioned by astoria.

the only thing that does change is that the boat turns slower when loaded, but the change is harder to over come if you want.

for example, on the 1st afternoon of one trip, i realized that my yak was way front heavy - i had to be a little more on my toes to keep it from spinning when under way.

but if your yak will twist from side to side as you paddle - this is a good thing for you to practise with. Try high stokes and wide strokes and paddling close to the side of the yak and farther away - see how your strokes change how the yak moves thru the water. Especially with your yak, do not put the rudder down as it seems as if it will be a great yak to learn from.

rudders and their associated 'sloppy' pedals
well, rudders should not be associated or connected to sloppy pedals. there are many better choices that use the 'gas' pedal approach to deploying a rudder so that you do NOT put pressure on the cables and associated bits and you can still (foot) brace strongly and firmly.

these were just crap yaks with crap rudder setups. not good examples of the rudder system at it's best.
 

Doug_Lloyd

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Feb 29, 2008
Messages
526
lance_randy said:
So, you finally picked up that used Nordy LV. If you tire of it I'll buy it from you no problem. Looking for a used one to chop up for redeployment.

Skegs on a kayak. I thought that was why a paddler bought a boat with a skeg - so they could play with their skeg all day. :D

Doug L
 
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