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Question: Perfect Paddle Part Four :: Total Votes:16
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I prefer a large area "power" blade 4  [25.00%]
I like a smaller area "touring" blade 12  [75.00%]
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Topic: Perfect Paddle Part 4, Grips n' blades: hold onto yer hat!< Next Oldest | Next Newest >
Capn Jimbo Offline
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Posted: Aug. 13 2005,19:50

If you do nothing else (which is most of you) - VOTE - the results will be helpful.

In this section let's cover grips - no surprises here - and different blade areas - large vs small area blades - trust me you will be shocked at the findings!

To begin: quite simply there are three different types of grips: round, oval one side, and oval full length.

Broze feels, as we'd all agree, that oval paddles make it easier to know where your paddle is.  He believes round shafts are harder on the hands as they cause one to grip the paddle harder; also round shaft are more prone to accidentally spin out of control.  In contrast he felt oval paddles fit the hand better; for feathered paddles, oval paddles allow the pushing hand to push on the flat part.  Having the full length of the paddle oval also allows one to switch control hands when feathering.

I started out with an OK large diameter glass shaft 220 cm, right hand control.  I ran it unfeathered most of the time with the sole exception of paddling directly into high winds.  It was not until about 6 or 8 months ago I began using a full bladed, assymetrical carbon glass paddle, ovalized right side only.  I found this advantageous for knowing paddle position and was very effective when feathered.  Since I feather for right hand control only (and never left) I like having only the right side ovalized - particularly since I padded unfeathered perhaps 90% or more of the time.  

I now use a smaller-area, right-ovalized carbon 210 wing.

Ok, no surprises yet.  But blade area is a very different matter.  Let me quote Broze:

Quote
The most surprising result of my subjective tests was that large differences in blade area made little differences in performance.


What!?  Let me repeat that:  large differences in blade area made LITTLE difference in performance!  Now how could that possibly be?  Let's first see what the marketing boys are saying:

Aquabound promotes their larger area (7.25 x 18) Seaquel "...has plenty of power...to keep even shorter, wider kayaks moving along".  Their smaller area (6.25 x 18) Seaclude "...is smaller than the Seaquel... offers a smooth comfortable stroke... for those not requiring the full size blade of the Seaquel".

Whaddya think?  I used to believe that hype - the truth:  It's hogwash.  Quoting Broze:

Quote
I didn't notice ANY difference with one blade more than 20% larger than the other.


That is amazing.  Common knowledge is that, all things being equal, resistance should be directly proportional to the area of the blade.  But Broze theorizes that beyond some minimum blade area that did not slip, extra area would have no significant effect.  He also theorized that since resistance is proportional to the square of speed, that the smaller blade's speed - by moving faster through the water - compensated for the smaller area.  He gave an impressive example:

Many of us know of Chris Cunningham, an editor at Sea Kayak, and expert kayaker, instructor and builder of skin-on-frame kayaks.  Turns out that Cunningham won a race with a paddle that Broze lent him.  In the rush Broze had lent him a test paddle that had one paddle that was 25% larger in area than the other!   Cunningham caught and passed everyone, won the race.  Afterwards, Broze asked Chris what he thought of the paddle.

Cunningham replied "Why? Is there something wrong with it?"   It was only then Cunningham realized one paddle was much larger than the other.  He had noticed nothing during the race.  Broze speculated that Chris may have unconsciously adjusted his grip, but the point is made.  The difference, if any, was subtle.

In closing Broze makes clear that relatively small changes in paddle length can make as much difference as large differences in blade area and further, that major differences in blade shape can go unnoticed.  He noted that in one area large area blades DO make a difference...

In air.  Large area blades catch a lot more wind slowing you down and risking loss of paddle and/or control in high winds.  

Bottom line:  Small-area blades have the advantage. In strong winds they are much more efficient in the air while suffering little or no disadvantage in the water.

:capn:

Next:  blade shape and other matters...


Edited by Capn Jimbo on Aug. 14 2005,20:10

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Tight lines,
Capn Jimbo

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Flatdog Offline
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Posted: Aug. 14 2005,18:25

Captain:

What about blade shape; which shape enters the water more cleanly?

(Capn's Note:  comin up in Part Five)


Edited by Capn Jimbo on Aug. 14 2005,20:13
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Scupper Pro Frank Offline
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Posted: Aug. 14 2005,19:51

JIM-ONLY ONE OF OUR 6 PADDLES HAS GRIPS

All -ALL! -the others don't!  What do I do about the rest of them?  

And the grips on the only one we DO have grips on are round cross-sectionally, and longitudinally bent -and they will be round, for whatever shaft I put them on, untill I put them on the shaft, at which point they will assume the both the cross- and longitudinla section of the shaft upon which they are placed.

But I must admit -I have yet to see an oval paddle -or a round one, for that matter...  Now, you must agree that either round OR oval, they'd be pretty dang inefficient, doncha think!  I mean, where thje heck could you get a hold of one of them things?  Unless they were small -the equvalents' size-wise, of a hand-held GP.

Me?  I prefer mine more or less kinda old-fashioned dumbell-shaped in profile, sort of sticks with blades on the end, right?  Know what I mean -right?   I bet you do too -hey, Cap'n, I've seen your paddles, and that's what they sure look like to me!  And that sticks-and-blades shape seems to more or less the norm for kayak paddles.

Now here it gets interesting -see, the shafts can be either round or oval!  Well, I suppose they could also be square, or dodecehedral for all I know, but oval and round seem to be more or less the norm for shafts.

Now we have a mixture of paddles at our place, and two are POS Caviness Al & plastic flat-bladed double-ended "oars"  that don't count and that I keep around only because they're backups and if we somehow get the whole fleet on the water at one time and we need to match a paddle for every boat theres something for everyone.  That, and I'm too cheap to buy better paddles for an unlikely event...

And of those, two are round-shafted, and tow are oval-shafted.  Sally's big Canon spoon and her Bending BRanches crank are round; my old Aquabound Seaclude and my Werner Mid-Tour are oval-shafted.

I've been paddling RH feathered for quite a while now, and the ovals are OK.  No problem with the left hand.  But I'm intrigued by the idea of the LH section being round, tho', and I wonder how common, or un, that approach is...?

Now Sally doesn't feather, and might be better off with an oval shaft on her Canon spoon.  But round is definitely the way to go for her Bending Branches crank, as there's no question of hand position, and round falls on the palm quite comfortably there.  Hers is the only paddle we have that has grips -and they're qute comfortable soft short -10" perhaps? -sections of what appears to be neoprene.  It really does make a difference -I should see about finding some grips for for most of our paddles.

One good thing I in particluar gain from grips that I don't from a bare shaft is equidistant placement of my hands along the length of the shaft.  For some reason, I'll gradually shift the paddle in my grip and I'll find myself paddling assymetrically somewhere down along the line...  Strange, but what can I say?  It happens, and happens consistently.  I've taken duct tape and bult up small raised grips that are not for comfort but to let me know by feel where my hands should be on my big 240 cm Aquabound Seaclude.

So that's the story on grips vs. shafts.

And now that you know, get a grip -on your shaft, and MAYBE a grip on a grip that's ON your shaft -whether round, oval, or both, with blades straight, or feathered, and


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PALADIN Offline
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Posted: Aug. 15 2005,04:34

If your looking for good paddle grips Yakpads make some good ones...

Yak Grips


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               Mike
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Posted: Aug. 20 2005,15:12

I have a few questions about this discussion.  

I think we all agree that the paddle works by creating resistance against the water.  With the water being more difficult to move than the kayak, the kayak moves forward.  Simple enough.

I think we can also agree that the more paddle strokes over a period of time--be that a second, a minute or a day--the faster and, therefore, the farther you will go.

I think we should also be able to see that the larger the surface area of the paddle, the more resistance it will have against the water.  As a matter of fact it is exactly the square of the surface area of the paddle.  That's high school physics.

Sooooo....the larger the surface area of the paddle, the faster and farther you will go.  ALL OTHER THINGS BEING EQUAL.

And that last qualification is important.  If you can't move a large paddle face as quickly and as efficiently through the water as you can a smaller faced paddle then the differences will even out as you move the larger paddle more slowly.

But, if Broze can theorize about speed he needs to also theorize about surface area.  What evidence does he offer to support his theory that surface area's affect has some kind of arbitrary limit?  That after a certain point it stops working. His only evidence is that one paddler didn't notice that one blade was larger than the other.  I wouldn't try to build a Phd. thesis on one example.  We may have had other factors working here which we will never know.  Did the paddler unconsciously grip the shaft off-center to adjust for the different resistence?  Was there a quartering wind during the paddle that favored the blade arrangement and led it to be unfelt?  Was there a significant difference in the blade shape to affect the results?  We don't know.

We do know that resistance is directly proportional to square of the surface area and if it works for wind it works for water.  Can't have it both ways.  There is no place in physics for Broze to arbitrarily decide the effect ends because he thinks it does.  

If you can paddle a larger blade as efficiently as you can paddle a smaller blade you will go faster.  Paddling has to suffer with the same laws of physics as rocket scientists whether they like it or not.

BTW, it is a hypothesis until it can be supported by statistically significant evidence.  THEN it is a theory and recognized as fact until evidence can be found to undo it.  That's how science works.  When people say "I have a theory about that!" they really mean they have a hypothesis yet to be tested.
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Capn Jimbo Offline
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Posted: Aug. 22 2005,18:25

Quote
Don - "I think we should also be able to see that the larger the surface area of the paddle, the more resistance it will have against the water.  As a matter of fact it is exactly the square of the surface area of the paddle.  That's high school physics".


No Don.  It is SPEED that is the square (double the speed, QUADRUPLE the resistance).  Paddle area is only directly proportional to resistance (double the area, only double the resistance/power).  Broze's point was that a relatively small increase in the speed of the stroke and/or the length of the paddle had as much effect as a large increase in blade area.

Let's put some numbers on this.  A mere 3% increase in paddle speed would equal a 10% increase in blade area.  Paddle 4.5% faster - that would take a 20% increase in paddle area.  And a 5.4% increase in paddle speed - you'd need a 30% increase in paddle area!  Hope you see a trend here...

Increasing paddle area is NOT the way to gain performance.  Not to mention you'd now be stuck with a much larger, heavier, clunkier and wind-catching sail, er blade.  Not to mention a higher and more debilitating swing weight.

Not me.

And I do hope you didn't misunderstand the Chris Cunningham example. This was just an fascinating tidbit; Broze's conclusions were based on years of experimentation and personal testing.  He made numerous changes in paddle shape and area, carefully isolating such factors as shape, perimeter, area, curvature and the like.  His primary test intrument was himself and a handful of other very experienced and respected author/kayakers.  

Quote
Don - "We do know that resistance is directly proportional to square of the surface area and if it works for wind it works for water.  Can't have it both ways".


At least this time you've got the relationship right.

But sure you can have it both ways and Broze explains why.  In water you can achieve the same force with a smaller blade via a relatively small increase in length and/or paddle speed.  And as you swing the paddle through the air - all other things being equal - the smaller blade will catch much less wind than a blade that is 30% larger (this is an often cited advantage of Greenland paddles).  For now let's ignore the obvious differences between water - a dense, heavy and incompressible medium in which we plant our paddle and push against - and air - a very, very thin, almost weightless and compressible medium that we certainly cannot push against, but can certainly move our paddle.

Let's forget misrecalled high school physics and the lesson on scientific method.  Let's concentrate on learning from a legitimate expert in the art of kayaking who took painstaking time and effort to learn and share his valuable lessons with us.

:capn:


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Capn Jimbo

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randrums Offline
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Posted: Mar. 02 2006,19:13

The difference I notice between smaller and larger blades is in acceleration, braking, and maneuvering. But at "cruising speed", I like the smaller blade. The Epic relaxed tour model is the stick I'm in love with. Still haven't tried a wing, though.
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PALADIN Offline
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Posted: Mar. 03 2006,16:42

Paddle hype is gearhead heaven. If people were more concerned with Kayak design and technique then all this exotic paddle junk would be a mute point.
The Inuit and Aluet proved this over and over. Their Qajaq or Kayak was exquisite in design and the bases for all good design today. I confidently say none of us could ever compare to their prowess and skill.... and yet they used a paddle carved from driftwood. Many people today have gone back to the GP for many reasons, most importantly relating to less joint stress and better bracing.

Having said that, there is nothing wrong with the Euro paddle, but it blows my mind how many non-olympic paddlers feel they need to pay enormous amounts of cash to paddle... well as they say "a fool and his/her money"

:cool:


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               Mike
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Kiyu Offline
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Posted: Mar. 04 2006,12:03

Lets see, He is saying that if you take a smaller paddle and paddle faster ie, speed through the  water, it will move a kayak as fast as a paddle thats not over 20% larger paddling slower. Well that sounds logical, but I have no idea why you would would want to do that, since if you paddled the lager paddle at the same speed, you will be going faster, sounds easer to me. ???
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Capn Jimbo Offline
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Posted: Mar. 04 2006,16:47

Kiyu, you've almost got it, but you are comparing blade speed rather than force.  Broze's observation is (properly) based on the notion that we as paddlers are trying to achieve a certain (comfortable) force that we can maintain over time.

His point is that a smaller blade can achieve the same force as a much larger blade with only a very minor increase in paddle speed.  This increase in speed is so minor that we hardly even notice it, yet we are achieving the same force as the larger blade.

So far so good - both the larger and smaller paddle are now creating the same force.  It's a wash.  But the smaller blade has a significant advantage in that it has significantly less wind resistance.  The smaller is also significant lighter in swing weight, which really adds up over thousands of strokes.

Bottom line:

Same force, less wind resistance, less swing weight.  Game, set and match to the smaller blade.

:capn:


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Capn Jimbo

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