Why Rudders?

Do you have a rudder?

Yes
65
36%
Yes, but I have a pedal boat
16
9%
No
100
55%
 
Total votes: 181

Skipjack
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Why Rudders?

Post by Skipjack »

I have never understood the concept of putting rudders on Paddled Kayaks. In the case of pedal boats it makes perfect sense because you have no way to steer the boat otherwise. But why a Paddled Kayak? You can control the direction with your paddle stroke? What are the benefits? I've also added a poll to see how many people use them.

Here are my questions / concerns..
If you consider the drag of the rudder, is it worth it?

Here is the equation to calculate Viscous Drag.
Image

I've done the math for you guys. AND I have made some very wild assumptions. Which we all know can't be possible. But it makes the math easy.

1) I assume you can keep the rudder exactly straight at an angle of 0º to the direction of travel
2) Laminar flow across the rudder

What I find is that you lose an efficiency of 12% when you dip that rudder in the water. The efficiency seriously goes way down when you turn the rudder at an angle of just 5 degrees. Then the math gets really complicated. Basically, you can lose up to 1 mph or more when you adjust that angle.
Image

Image
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freespool
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Re: Why Rudders?

Post by freespool »

Quick answer (for me):

You can control your drift while fishing. No paddle needed, so your hands can cast a rod. If you want to, raise the rudder when paddling.
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Re: Why Rudders?

Post by mojosoul »

who's racin' in yaks while out fishin'. The math is not needed. These are not rocket ships...
I use it to HELP keep me in line with a head wind. Instead of a bunch of corrective strokes to one side of da boat. :?
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Re: Why Rudders?

Post by Skipjack »

freespool wrote:Quick answer (for me):

You can control your drift while fishing. No paddle needed, so your hands can cast a rod. If you want to, raise the rudder when paddling.
Yeah, I figured if you have the option to raise the rudder. Do it while paddling. If you are using it to control a drift that sounds reasonable.

Anyone else?
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Re: Why Rudders?

Post by fish dirty »

Do all the math u want,heres mine 20+mph wind - 1 rudder=CRAPPY DAY.Seriously it makes it a hell of alot easier to stay on track.You dont even realize its back there until u need it.
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Re: Why Rudders?

Post by Moonstomper »

Wow. That's the exact calculation I did before I installed the rudder on my X-13. :roll:



Actually the only time I really appreciate having a rudder is when I drift. I use it when paddling sometimes and other times I forget it's down.

Is it worth it?
IDK, but I prefer to have one.
Too each his own.
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Re: Why Rudders?

Post by toefu »

for windy days (when is it NOT a windy day?) it's nice to not have to do 2 strokes on the left then 1 stroke on the right. It's just a lot more natural to paddle left-right-left-right.
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Re: Why Rudders?

Post by redneckmorton »

I had a Trident 15, and with the longer kayak it made it easier to turn the boat around and make sharp turns. With out it I would have to do a lot more strokes when trying to turn then with it. I never noticed it to slow me down any. It just helps you to make faster turns in tight areas. Can't say it would help much out BTB though. But in the back waters it sure did.
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Re: Why Rudders?

Post by eweberdc »

1. Easier turns while paddling
2. Easy drifts with the current
3. Less corrective strokes when paddling cross-current
4. Less corrective strokes for those guys (like me) with a poor paddling technique :lol:
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Re: Why Rudders?

Post by Skipjack »

So the general consensus here is that the benefits outweigh the loss in speed or loss in efficiency.

In some cases where the users have poor technique it may actually be a benefit! The net direction and speed is greater with a rudder than without! HA!

Thanks fellas for the comments.

I plan to do some experiments to evaluate these claims. Every time I drift with the rudder down it seems I always travel the same direction. But, I'll try it again to see if there are any differences.

In the cases where you have the long boats that are meant for tracking and speed, the rudder comes in handy for turning sharply. I can see the benefits there. Personally I haven't had the need to turn sharply much. But, for those boats like the tarpon 160 or trident 15 I can see the benefits in those cases.

In the case of a windy day, well.....yes, tis true. The slower you go the less drag that will be noticed by the rudder. It may not even be significant at a speed of say 0.5 miles per hour. If it helps that much then by all means keep using that rudder to help keep you straight in the wind.

Reason I am asking all this is because I am trying to decide whether or not to put a rudder on my wife's kayak. Plus, I am just a little looney when it comes to explaining things on earth. Always have a scientific perspective.
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Re: Why Rudders?

Post by pdt818 »

Some models actually benefit from the addition of a rudder. Take the trident lineup. The Trident 11 tracks the truest without a rudder, but I highly recommend a rudder on the 13 and 15. The boat has a high profile and will catch a lot of wind. Also the boats will pull into the wind, which is the main reason why I had a rudder on my 13. They are just more efficient boats with them added. Some models can do without, but once you start getting into the longer models a rudder is a great option to add. I do agree that some of the points that people make as being the reason they need it can be corrected with proper paddling technique. I also liked having it for setting up drifts in wind or current.

Now offshore the use for a rudder is almost non existent unless you are drifting or trolling. A rudder won't do anything for you though if you are just sitting still. They are also useless for launching and re-entering the surf zone.
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Re: Why Rudders?

Post by DSmithla »

Skipjack wrote:So the general consensus here is that the benefits outweigh the loss in speed or loss in efficiency.

In some cases where the users have poor technique it may actually be a benefit! The net direction and speed is greater with a rudder than without! HA!

Exactly. You're dead bang on. That's why so many hard core ocean paddlers (in sea kayaks, not on SOTs) have skegs. To compensate for their poor technique. :roll:
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Re: Why Rudders?

Post by Rod Pod »

I have a Trident 11 and it SUCKS when it's windy. Last week, while paddling back, I took 4 strokes on the left, and on on the right.... I really wish I had a rudder... I am ordering one as soon as I collect the finances.
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Re: Why Rudders?

Post by pdt818 »

All of the trident series is this way. The 11 just does it the least. Crazy huh :!:
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Re: Why Rudders?

Post by Harold Ray »

In my opinion, having a rudder makes it a lot easier to make a kayak, paddled, peddled, or sailed, go where you want it to go. I'm just an Aggie Veterinarian :roll: and don't know much about the ways of the world, but that's what I thought rudder were for! :D

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Re: Why Rudders?

Post by Harold Ray »

Do you have a rudder?

Yes
Yes, but I have a pedal boat
No

You may select 1 option
I posted, but this dude wouldn't let me vote! I am broken hearted!
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Re: Why Rudders?

Post by Coastal Country »

DebiB's response to the question of "Why do I need a Rudder???" Is

"Its like power steering, you can drive a pick-up without it but do you REALLY want too???"

Your last graph doesn't really show me a loss in hull speed to make me lose sleep over putting that "Anchor" :wink: :lol: :lol: of a rudder down.

Now if you told me I was losing 10mph I'd go out to the truck right now and cut it off :lol:
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Re: Why Rudders?

Post by Lance »

Maybe I'm beating a dead horse, but I'll chime in anyhow.

I own kayaks with and without rudders. Rarely do I ever paddle from A to B with the rudder down. I use mine for control when drifting in order to keep my hands free for fishing. I like the power steering analogy for those windy days.
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Re: Why Rudders?

Post by Mythman »

Well your poll didn't work for me.

No one need a rudder on a paddle kayak..............just like no one needs a cruise control on a vehicle........but they both sure are convenient to have! :roll:

When I paddle a kayak with a rudder in the wind, I never lose an even paddle stroke as I do not need to paddle more on one side to the other to keep the kayak straight. The direction is controlled by my feet and therefore I never miss a beat with a continuous, even paddle.

Pretty nice in the wind.........but not necessary.
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Re: Why Rudders?

Post by Crazy Yak »

Quit overthinking the rudder dilemma :roll:! Put a rudder on that sucker and take her fishing!
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Re: Why Rudders?

Post by Harold Ray »

Quit overthinking the rudder dilemma ! Put a rudder on that sucker and take her fishing!
I like Crazy's answer; sometimes we just analyze tooooooooooooooo much! :D
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Re: Why Rudders?

Post by fishnv »

Would you buy a car without power streeing?
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Re: Why Rudders?

Post by Skipjack »

Javelina Russ wrote:DebiB's response to the question of "Why do I need a Rudder???" Is

"Its like power steering, you can drive a pick-up without it but do you REALLY want too???"
Its not like power steering.......unless power steering involves you adding a 12% drag to your car because of utilizing it.
Javelina Russ wrote: Your last graph doesn't really show me a loss in hull speed to make me lose sleep over putting that "Anchor" :wink: :lol: :lol: of a rudder down.

Now if you told me I was losing 10mph I'd go out to the truck right now and cut it off :lol:
Keep in mind, that is not a loss in hull speed. Its a graph displaying viscous drag in pounds. Hull Speed is entirely different, however they are related. Hull speed is a useless figure because I seriously doubt anyone travels in kayaks at the hull speed unless you have muscles like the Hulk and prefer to Kayak to your fishing spot as fast as you can. Our speed always varies and therefore its best to calculate viscous drag and minimize this figure as best as possible. Get the biggest bang for your buck.

The calculations above represent the BEST CASE scenario. You can't think of it in terms of only a mere 12% Loss. You can't maintain perfect rudder control while paddling and therefore the efficiency loss is even worse than the calculated 12%. If you paddle with your rudder up then you are one step ahead of the game and these calculations are simply justification for your purposes of paddling with the rudder up.

I've got pros and cons to having a rudder.

It seems that having a rudder is more advantageous than otherwise. You can pull it up and paddle around without the rudder down to get that extra glide and travel and extra 12%(OR MORE) with each paddle stroke. If you are traveling long distances with little wind this is a good option. Yet, if you need the rudder, just put it down in the water and make your turns or drift or battle with the wind. Its a good "There when you need it" type of option. Like the Boy Scouts say "Be Prepared"
fishnv wrote:Would you buy a car without power steering?
It depends? For the same model would I improve my gas mileage by 12% if I bought a car that didn't have power steering? Is most of my travel in one direction without turns? If these answers are yes, Then yes, I would buy a car without power steering because the benefits outweigh the negative.
Harold Ray wrote:
Quit overthinking the rudder dilemma ! Put a rudder on that sucker and take her fishing!
I like Crazy's answer; sometimes we just analyze tooooooooooooooo much! :D
Its only overthinking when the effort and time spent thinking causes me to be in-decisive and not make a decision based upon findings. When in fact I have made my decision based upon my findings.

So.......I think I am in the clear. Oh wait...am I overthinking the definition of overthinking? LOL
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Re: Why Rudders?

Post by Skipjack »

Mythman wrote:Well your poll didn't work for me.

No one need a rudder on a paddle kayak..............just like no one needs a cruise control on a vehicle........but they both sure are convenient to have! :roll:
You said it best. Its convenient.

As for the poll??? It didn't work for me either. Must be a problem with the Forum.
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Re: Why Rudders?

Post by DSmithla »

Skipjack wrote:
It seems that having a rudder is more advantageous than otherwise. You can pull it up and paddle around without the rudder down to get that extra glide and travel and extra 12%(OR MORE) with each paddle stroke. If you are traveling long distances with little wind this is a good option. Yet, if you need the rudder, just put it down in the water and make your turns or drift or battle with the wind. Its a good "There when you need it" type of option. Like the Boy Scouts say "Be Prepared"

Personally I prefer an adjustable skeg, but those are pretty rare on fishing kayaks. :cry:
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