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From: John Gibbs <johngibbs_at_charter.net>
subject: [Paddlewise] Paddle flutter
Date: Thu, 29 Nov 2001 15:36:07 -0500
Greetings from a new PaddleWise member, and a new paddler, in Roswell, GA, 1/4
mile from the Chattahoochee River.





After a couple weeks' paddling my new Zoar Sport kayak with the flat-blade
Carlisle I bought as a spare, I received shipment of a Eddyline MidSwift
paddle. It's nice and light, and I like the blade size, but I notice a fairly
pronounced flutter, as it gyrates a bit on its axis a couple cycles per
stroke. I'm deciding whether to return it and order a Lightning paddle or
something else.





Is this flutter a paddler issue I can correct without implementing a death
grip? I'm trying to form the practice of holding the paddle lightly to protect
my 48-year-old wrists that get enough abuse from the mouse and the keyboard.
If it's an unavoidabler feature of this paddle, should I consider it a
substantial performance or ergonomic liability?









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From: Steve Holtzman <sh_at_actglobal.net>
subject: RE: [Paddlewise] Paddle flutter
Date: Thu, 29 Nov 2001 14:02:55 -0800
Ah The Chattahoochee--I remember well my alma mater
"Far above the Chattahoochee,
Near the......

Stands our loyal alma mater Benning School For Boys".

As far as the paddles go, I use a MidSwift as my normal paddle, my spare is
a SeaSwift (also used in large seas), my wife uses a MidSwift, and many of
my friends also use Swift paddles. Nobody to my knowledge has ever had blade
flutter. I would suggest getting in touch with Eddyline and asking them
about it.

The reason my wife has a MidSwift now is because one day she tried mine in
stead of her all carbon paddle. She fell in love with it and had to have one
because it is easier to use than her other paddle. The only way someone will
get mine is if they pry my cold dead fingers off of it. ;-)

Steve Holtzman

> -----Original Message-----
> From: owner-paddlewise_at_paddlewise.net
> [mailto:owner-paddlewise_at_paddlewise.net]On Behalf Of John Gibbs
> Sent: November 29, 2001 12:36 PM
> To: PaddleWise_at_paddlewise.net
> Subject: [Paddlewise] Paddle flutter
>
>
> Greetings from a new PaddleWise member, and a new paddler, in
> Roswell, GA, 1/4
> mile from the Chattahoochee River.
>
>
>
>
>
> After a couple weeks' paddling my new Zoar Sport kayak with the flat-blade
> Carlisle I bought as a spare, I received shipment of a Eddyline MidSwift
> paddle. It's nice and light, and I like the blade size, but I
> notice a fairly
> pronounced flutter, as it gyrates a bit on its axis a couple cycles per
> stroke. I'm deciding whether to return it and order a Lightning paddle or
> something else.
>
>
>
>
>
> Is this flutter a paddler issue I can correct without implementing a death
> grip? I'm trying to form the practice of holding the paddle
> lightly to protect
> my 48-year-old wrists that get enough abuse from the mouse and
> the keyboard.
> If it's an unavoidabler feature of this paddle, should I consider it a
> substantial performance or ergonomic liability?
>
>
>
>
>
>
>
>
>
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>

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From: Leonhardt, William J <wjleonhardt_at_bnl.gov>
subject: RE: [Paddlewise] Paddle flutter
Date: Thu, 29 Nov 2001 17:16:01 -0500
  John Gibbs said:

>After a couple weeks' paddling my new Zoar Sport kayak with the flat-blade
>Carlisle I bought as a spare, I received shipment of a Eddyline MidSwift
>paddle. It's nice and light, and I like the blade size, but I notice a fairly
>pronounced flutter, as it gyrates a bit on its axis a couple cycles per
>stroke. I'm deciding whether to return it and order a Lightning paddle or
>something else.


Then Steve Holtzman said:

>As far as the paddles go, I use a MidSwift as my normal paddle, my spare is
>a SeaSwift (also used in large seas), my wife uses a MidSwift, and many of
>my friends also use Swift paddles. Nobody to my knowledge has ever had blade
>flutter. I would suggest getting in touch with Eddyline and asking them
>about it.


Hi John and Steve, et.al.,

After paddling  a few years with a variety of  "clubs", I bought a 
Lightning Standard Tour.  When I first used it (graduating from the clubs), 
it felt like it fluttered a little.  This worried me but I decided to stick 
with it.  In a very short time, the fluttering went away.  In reality, I 
think the paddle trained me.

I've never tried a MidSwift.  I love my Lightning and, if I lost it 
tomorrow, I'd go out and get another one ASAP.

I guess the bottom line here is: "Give the new paddle some 
time."  Naturally, we'd (at least me) would like you to report back to see 
if the paddle trains you.

Good luck,

Bill Leonhardt
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From: Michael Daly <michaeldaly_at_rogers.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Thu, 29 Nov 2001 17:12:59 -0500
From: "John Gibbs" <johngibbs_at_charter.net>

> [...] Eddyline MidSwift paddle. It's nice and light, and I like the blade size, 
> but I notice a fairly pronounced flutter, as it gyrates a bit on its axis a 
> couple cycles per stroke.
> 
> Is this flutter a paddler issue I can correct without implementing a death
> grip?

All paddles will flutter, but you should be able to control it without a death
grip.  I'd say if you can't control it with a reasonable grip, it's a defective 
design.  Most good paddles only exhibit flutter when gripped _very_ lightly.

> I'm deciding whether to return it and order a Lightning paddle or
> something else.

Not a bad plan.  The paddle is as important as the kayak.  Get a good one.
If you're worried about your joints, try a bent shaft and see if you prefer it.
You might also try different feather angles before putting the money down.

Mike

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From: Steve Scherrer <Flatpick_at_teleport.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Thu, 29 Nov 2001 14:35:21 -0800
Try tilting the top edge of the paddle forward just a hair off vertical.
This will put a bit of a load tension on the blade and may stop it from
cavitating.  You can actually tilt it forward a bunch, a trick I learned
with a Greenland paddle, for a whole different, and IMHO, effecient stroke.

Light paddles are quite noticable when they flutter, especially with a death
grip.

Lightnings can flutter as well.

steve
aldercreek.com


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From: Nick Schade <schade_at_guillemot-kayaks.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Fri, 30 Nov 2001 09:46:19 -0500
Paddle flutter is rarely a defect of the paddle. It is vortex 
shedding off the blade, any paddle pulled straight and square will 
shed whirl pools off one edge then the other causing it to flutter. 
The solution is to tilt the top edge of the blade forward slightly. 
This will force the vortex to be on the bottom edge of the blade 
only. The result is a paddle that produces some lift and is thus more 
efficient, plus it doesn't flutter.
Nick

>Greetings from a new PaddleWise member, and a new paddler, in Roswell, GA, 1/4
>mile from the Chattahoochee River.
>
>
>
>
>
>After a couple weeks' paddling my new Zoar Sport kayak with the flat-blade
>Carlisle I bought as a spare, I received shipment of a Eddyline MidSwift
>paddle. It's nice and light, and I like the blade size, but I notice a fairly
>pronounced flutter, as it gyrates a bit on its axis a couple cycles per
>stroke. I'm deciding whether to return it and order a Lightning paddle or
>something else.
>
>
>
>
>
>Is this flutter a paddler issue I can correct without implementing a death
>grip? I'm trying to form the practice of holding the paddle lightly to protect
>my 48-year-old wrists that get enough abuse from the mouse and the keyboard.
>If it's an unavoidabler feature of this paddle, should I consider it a
>substantial performance or ergonomic liability?
-- 
Nick Schade
Guillemot Kayaks
824 Thompson St
Glastonbury, CT 06033
(860) 659-8847
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From: Joe Pylka <pylka_at_castle.net>
subject: Re: [Paddlewise] Paddle flutter
Date: Fri, 30 Nov 2001 13:58:42 -0500
> The people I've talked to who had problems with paddle
> flutter usually report it goes away seemingly of its own accord.
> Since it is unlikely the paddle got better, it is more likely they
> adjusted their technique without knowing it.
>
        Around here paddlers have noted that some canoe paddles are more
prone to flutter than others.  This seems to be directly related to how
large a bulge is produced where the shaft forms into the blade.  My
Mitchells, with very little bulge, flutter far less than the Sawyers, which
carry the shaft body much further down the blade area...


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From: John Gibbs <johngibbs_at_charter.net>
subject: Re: [Paddlewise] Paddle flutter
Date: Fri, 30 Nov 2001 14:06:10 -0500
Thanks to all for the hydrodynamic and ergonomic insights and tips. What a
helpful and knowledgeable group!

I'll try various techniques this weekend and report back.
1. Vary power of stroke.
2. Vary rotational angle.
3. Straighten entry into water (although with about 1" of longitudinal curve
in the blades, I might not be able to completely avoid trapping air.)

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From: Mike McNally <mmcnally3_at_prodigy.net>
subject: Re: [Paddlewise] Paddle flutter
Date: Fri, 30 Nov 2001 21:24:07 -0600
I have a werner carbon fiber and I found I could use little or no grip
on the push hand (to stretch fingers at the end of a long days paddle),
and a lite grip on the pulling hand.  This did cause some flutter, but
putting a real tiny twist on the blade made it acceptable for one handed
grip paddling.  Putting a couple degrees or so of angle off of the norm
created a weird feel and I thought was inefficient.  

I here wing paddles
are a design that is optimized for putting pressure down on the water.
It would seem a mistake to pull up with a paddle as that would lenghten
the waterline and effective mass of the boat.  You'd be expending energy
which would work against you by both increasing effective mass and
wetted surface area.  The wing paddle would do the opposite.

But I'm no expert.
-- 

Mike McNally		mmcnally3_at_prodigy.net

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From: Michael Daly <michaeldaly_at_rogers.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Fri, 30 Nov 2001 18:05:46 -0500
From: "Nick Schade" <schade_at_guillemot-kayaks.com>

> At 12:56 PM -0500 11/30/01, Michael Daly wrote:
> >Snip>
> >Tilting the blade enough will eliminate the symmetry and reduce the problem,
> >as some have suggested.  This, however, sounds like the wrong approach
> >IMHO.  Good paddles don't have objectionable flutter even if drawn straight
> >through the water.
> 
> There is a good explanation of the benefit of angling the blade 
> slightly at: http://courses.washington.edu/phys208/notes/lect19.html
> 

That's a good article.  I had to check the author, as his insistence on the
unsuitability of conventional Bernoulli explanations matched those of a 
physics prof I used to know.

I'm not saying that there are no benefits to generating lift.  I'm saying that the
paddle John bought shouldn't exhibit high flutter under any conditions.  When
I play with paddles so as to force flutter, none of the decent paddles I've used
generates excessive flutter.  Since moderate flutter is the current state of the
art for kayaking paddles, the Eddyline should be similar*.  I don't know why the
Eddyline isn't similar, but it should be Eddyline's problem, not John's.  I've only
once used a Carlisle, which he also used without problem, but it's a dog in my
opinion and is suitable only for a spare (assuming, of course, it's the same flat 
design with no distinction between power and non-power faces).  If he's not 
having a problem with that one, I'd expect the Eddyline to be better, not worse.  
Why it isn't, I don't know - but I'm not prepared to advocate changing technique 
until it can be demonstrated that the problem is in John and not the paddle.  
Hence, he should try several paddles and see what prevails.

With regard to the Eddyline paddle - does it have a smaller diameter shaft than
most paddles?  Is it particularly flexible?  And John, how far apart are your hands
when you hold the paddle?

Mike

*I'll change my tune for paddles designed specifically for recreational paddlers
using high lift which have poor flutter characteristics when used in "drag mode".  
I'm not aware of such paddles at this time.

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From: Nick Schade <schade_at_guillemot-kayaks.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 10:36:10 -0500
At 6:05 PM -0500 11/30/01, Michael Daly wrote:
>I'm not saying that there are no benefits to generating lift.  I'm 
>saying that the
>paddle John bought shouldn't exhibit high flutter under any conditions.  When
>I play with paddles so as to force flutter, none of the decent 
>paddles I've used
>generates excessive flutter.  Since moderate flutter is the current 
>state of the
>art for kayaking paddles, the Eddyline should be similar*.  I don't 
>know why the
>Eddyline isn't similar, but it should be Eddyline's problem, not 
>John's.  I've only
>once used a Carlisle, which he also used without problem, but it's a dog in my
>opinion and is suitable only for a spare (assuming, of course, it's 
>the same flat
>design with no distinction between power and non-power faces).  If he's not
>having a problem with that one, I'd expect the Eddyline to be 
>better, not worse. 
>Why it isn't, I don't know - but I'm not prepared to advocate 
>changing technique
>until it can be demonstrated that the problem is in John and not the paddle. 
>Hence, he should try several paddles and see what prevails.
>
>With regard to the Eddyline paddle - does it have a smaller diameter 
>shaft than
>most paddles?  Is it particularly flexible?  And John, how far apart 
>are your hands
>when you hold the paddle?

I am not ready to concede that a "good" paddle design will never 
flutter, however others have used the same model paddle and had no 
problem. So, either the manufacturer has changed the paddle, the 
individual paddle is defective, or the paddler is doing something 
different.

It is certainly not out of the question that the manufacturer made 
changes, but it would have to be fairly dramatic changes such as 
changing the shape which usually would be labeled as a different 
model. Any physical defects in the paddle itself should be evident to 
inspection, i.e. the blade is loosely glued to the shaft or something 
else that effects the flex of the paddle. More likely the paddler is 
doing something different. The subtleties of paddling technique leave 
a lot of room for variation, some of which will make flutter more 
likely. All it takes is a slight change in blade angle to completely 
eliminate the flutter. Just a degree or so will often do the trick. 
This will have virtually no effect on the drag of the paddle when 
drawn straight back if that is your preferred technique.

However, a simple straight back stroke will take a single mass of 
water and accelerate it until you end the stroke. You can increase 
you efficiency slightly if the blade is always pushing against almost 
still water. This is part of the principle behind the efficiency of a 
wing paddle where the stroke angles out to the side slightly.
-- 
Nick Schade
Guillemot Kayaks
824 Thompson St
Glastonbury, CT 06033
(860) 659-8847
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From: Michael Daly <michaeldaly_at_rogers.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 11:17:09 -0500
From: "Nick Schade" <schade_at_guillemot-kayaks.com>

> I am not ready to concede that a "good" paddle design will never 
> flutter, 

I'm not asking you or anyone else to do that.  I said that all paddles
flutter to some extent and that moderate flutter is the norm.

>however others have used the same model paddle and had no 
> problem. So, either the manufacturer has changed the paddle, the 
> individual paddle is defective, or the paddler is doing something 
> different.

I agree.  That's why I suggested that John try other paddles and attempt
to resolve the issue rather than stick with the paddle and change his
technique.  Once he identifies the problem, he can look to a solution.

Mike

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From: Steve Scherrer <Flatpick_at_teleport.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 08:43:51 -0800
Mike writes:

>>I play with paddles so as to force flutter, none of the decent
>paddles I've used
>generates excessive flutter.

 and then Nick writes:

>>. More likely the paddler is
doing something different. The subtleties of paddling technique leave
a lot of room for variation, some of which will make flutter more
likely. All it takes is a slight change in blade angle to completely
eliminate the flutter.

My response:

I don't know what *decent paddles* Mike plays with but, in this cowboys
opinion, with proper paddle play one can get any paddle to flutter
excessively. I agree with Nick, it's something the paddler does or in Mike's
case doesn't do.  Flutter could be described as a very fast sculling stroke
in the vertical plane.  The leading edge of the paddle blade changes
direction rapidly.  I can make an A/T, Lightning, Big Spoon, Superior
Greenland,  Betsie Bay Greenland, Werner, and yes the Swift by Eddyline,
etc. etc. paddle flutter.  I adjust the blade angle, shaft angle, pivot
point, thrust/ power, and grip of every stroke I take.  If I have serious
control of all these aspects of blade articulation I can eliminate or
generate flutter, lift, support, motivation, etc.

It's what we all do:  PADDLE!

Steve
aldercreek.com


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From: Michael Daly <michaeldaly_at_rogers.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 12:55:41 -0500
From: "Steve Scherrer" <Flatpick_at_teleport.com>

> Flutter could be described as a very fast sculling stroke
> in the vertical plane.  The leading edge of the paddle blade changes
> direction rapidly.  

If you choose to define flutter your own way, it can mean anything you want.
You're taking any form of instability to be flutter.  If you can't agree on a standard
terminology, there's no point is discussing anything.  Flutter as I've been discussing
it is caused by Karman vortex shedding.  Leading edge directional instability can 
be caused by other factors.  Most people I know will accept flutter to be a form
of instability when the power face is drawn through the water, normal to the 
face.  The change in direction of the power face cycles rapidly about the initial, 
nominally symmetric position.

>  I agree with Nick, it's something the paddler does or in Mike's case doesn't do. 

If you take a paddle and tie a string round the shaft and draw it straight through 
the water, power face forward, it will flutter.  When testing a paddle, I simulate 
that with an open lower hand - no grip at all - and push the non-power side of 
the shaft.  There isn't anything I am or am not doing to change the flutter.  
Moderate flutter can be controlled easily by a good grip, a stiff paddle shaft 
and/or good join between paddle and blade etc.  Just increasing shaft diameter 
can decrease the apparent degree of flutter by enabling the paddler to control 
with less force.  But the basic blade shape will determine the susceptibility of the 
paddle to flutter.  

As Nick and I have both said, the problem in this case could be a defective paddle, 
bad technique or other factors.  What I'm saying is that John needs to know the 
problem before he can devise a solution.  That's why trying different paddles may
help, and why I asked a few questions in my second to last post.

A long paddle with a slender shaft held with a close hand position (say, shoulder
width apart) will exhibit more flutter than the same paddle with a shorter shaft
held with hands far apart.  Is John using a long paddle as in the first case while
the others without the problem use a shorter paddle as in the second?  I don't
know - but if this is true, the problem could be that the paddle is a poor fit to
what John wants without either his technique needing to be changed nor the
paddle being defective (though I would suggest widening his hand position.)
 
We also haven't objectively determined what John's perception of excessive
flutter is - testing other paddles will help there as well.  But his experience with
the Carlisle suggests that isn't the problem.

Mike

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From: Alder Creek Kayak & Canoe <aldercreek_at_qwest.net>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 11:31:20 -0800
> If you choose to define flutter your own way, it can mean anything you
want.
> You're taking any form of instability to be flutter.  If you can't agree
on a standard
> terminology, there's no point is discussing anything.

The Webster's II dictionary I have actually defines flutter: "to flap or
wave rapidly *and* irregularly."

I would say that any form of paddle instability that causes rapid and
irregular waving or flapping could be called flutter.

Seems what we're discussing here is more of a regular wave with a defined
wave shape and length.  Maybe even a pulsed wave, caused by Karmen vortex
shedding.

>Most people I know will accept flutter to be a form
> of instability when the power face is drawn through the water, normal to
the
> face.  The change in direction of the power face cycles rapidly about the
initial,
> nominally symmetric position.


I'd say a super fast sculling stroke done vertically is an interesting way
to look at what we're discussing. I could demonstrate a very slow, drawn out
vertical sculling forward stroke that looks just like the pulsing wave
stroke we are discussing.

I also agree that all aspects of anyone's technique should be considered
when an irregularity like this comes up.  We sell a tons of paddles and have
yet to see one that was so far out of line that *flutter* was a problem.

Steve _at_ work
Alder Creek Kayak & Canoe    N   45º 39' 47"
250 NE Tomahawk Isle Dr.     W 122º 36' 16"
Portland, OR  97217          Web: www.aldercreek.com
Phone: 503.285.0464        Email: aldercreek_at_qwest.net


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From: Erik Sprenne <sprenne_at_netnitco.net>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 13:53:55 -0600
> From: "Steve Scherrer" <Flatpick_at_teleport.com>
>
> > Flutter could be described as a very fast sculling
stroke
> > in the vertical plane.  The leading edge of the paddle
blade changes
> > direction rapidly.
>
From: "Michael Daly" <michaeldaly_at_rogers.com>
> If you choose to define flutter your own way, it can mean
anything you want.
> You're taking any form of instability to be flutter.  If
you can't agree on a standard
> terminology, there's no point is discussing anything.
Flutter as I've been discussing
> it is caused by Karman vortex shedding.
>
Easy, Mike!
As I understand it, both of you are saying the same thing.


> But the basic blade shape will determine the
susceptibility of the
> paddle to flutter.
>
I agree - but also think that any standardized way of
measuring flutter will also influence the results in some
way.  Of course, one could then devise a test method biased
toward the desired results :-)

This discussion has been enlightening in that ways of
dealing with flutter have been discussed, and I sus pect
that Bill Leonhardt's advice of giving the paddler some time
to let the paddle 'train him' may be the best advice.

Hopefully John will try some of the suggested anti-flutter
techniques (and maybe even a few different sticks), and
report back what did and didn't work.

Regards,
Erik Sprenne


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From: Michael Daly <michaeldaly_at_rogers.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 18:08:28 -0500
From: "Alder Creek Kayak & Canoe" <aldercreek_at_qwest.net>

>> If you choose to define flutter your own way, it can mean anything you want.
>> You're taking any form of instability to be flutter.  If you can't agree on a standard
>> terminology, there's no point is discussing anything.
>
> The Webster's II dictionary I have actually defines flutter: "to flap or
> wave rapidly *and* irregularly."

> I would say that any form of paddle instability that causes rapid and
> irregular waving or flapping could be called flutter.

Except that Webster's isn't a standard reference in the realm of hydrodynamics.
My Webster's New World Dictionary (1976) defines oxygen as the most plentiful
substance in the universe - which it clearly isn't.  The English language often fails 
science and law - that's why scientists, engineers and lawyers can't be understood
by anyone else and why life scientists stick with Latin in many cases.  For science,
etc, the language can't be general, it must be specific.  That's my point wrt flutter.  
There are lots of forms of instability, but when most paddlers talk about flutter, they 
seem to mean the same thing.  We can dig up names for the other kinds of 
instability, if we need to discuss them.

> Seems what we're discussing here is more of a regular wave with a defined
> wave shape and length.  Maybe even a pulsed wave, caused by Karmen vortex
> shedding.

Calling it a wave is iffy, except in the context of having a regular frequency.  If you call
it a wave, that would influence the thinking of paddlers that are looking for it.  It's only
a wave in the sense that the sweep second hand of a watch can be described as a 
wave.  And yes, it would be pulsed as in +on, off, -on, off, +on, off -on, off..., though
the exact shape of "on" I could only guess.

Vortices peel off the edges of the paddle on alternating sides, first one side, then the 
other.  This tugs the paddle around, first one way then the other (as I said in another 
post, I can't see these; they seem to be swamped by the vortices that are caused by 
broken flow around the edge of the paddle, where vortices are visible at all).  In a 
steady state environment, this frequency can be predicted -hence, wave like.

Paddling isn't steady state, but there's a point in a draw-type stroke that will allow 
several oscillations, seemingly regular, to occur.  Most of us have felt this at some 
time.  Loosely holding almost any paddle and drawing it straight back will usually do it.

BTW, several folks have suggested that angling the paddle reduces flutter by 
generating lift.  I believe that they can angle the paddle enough to break the 
symmetry that can give way Karman vortex shedding without actually generating
much lift.  This intermediate point's existence would depend on the angle of 
attack at which stall would occur (I think).   (Intermediate, of course, meaning 
between high drag and high lift states - sort of "relatively high drag without much 
lift but we got rid of vortex shedding")  This set of complications is one thing that 
affects my lack of acceptance of "conventional" thinking on lift, wing paddles, 
Greenland paddles etc.  But that's another story...

> I also agree that all aspects of anyone's technique should be considered
> when an irregularity like this comes up.  We sell a tons of paddles and have
> yet to see one that was so far out of line that *flutter* was a problem.

Well, when one paddle works for John and another doesn't, I won't jump to
the conclusion that technique is to blame.  There are so many good paddles
on the market, I don't see the point in sticking with one that doesn't work for
him - whether or not it's his or the paddle's "fault".  The paddles I've tried that
flutter badly have been off the market for a while.  As I stated in another post,
I can see a case where the paddle is inappropriate for _him_ even though
it's fine for others.  If we can isolate the paddle as not part of the problem,
then certainly, let's critique technique.

I guess that I react when I see people go into "solution mode" when "analysis
mode" hasn't finished.  None of us has seen John or the paddle - I would
prefer to give him the benefit of the doubt and have him try other paddles.
If the problem is frequent with other paddles, we've narrowed it down.  As 
you and I have said, in different ways, the majority of paddles sold today 
are good.

Mike

PS - I can't help but notice that the vendors on this list tend to recommend 
changing the paddler rather than the gear - or is that my imagination :-)

PPS - I do get my back up when misquoted.  A couple of times in this thread
folks have suggested I said that paddles shouldn't flutter.  In fact I have repeated
that all paddles flutter, but some are better than others.  I apologize if I have
offended anyone with the apparent sharpness of my responses.

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From: Nick Schade <schade_at_guillemot-kayaks.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Mon, 3 Dec 2001 10:15:52 -0500
At 6:08 PM -0500 12/2/01, Michael Daly wrote:
>
>PS - I can't help but notice that the vendors on this list tend to recommend
>changing the paddler rather than the gear - or is that my imagination :-)


Sounds like a bad business practice if that's the case. It is easier 
to sell more product if you convince people that all they need is 
another "better" paddle. I suggested learning to deal with the paddle 
in hand because it was the paddle in hand and it seems a waste to go 
out and buy a different paddle when the one in hand will probably 
serve just fine with a small change in technique.

Someone suggested offline that I think highly of the the Eddyline 
paddle. I have no opinion about the paddle, I've never laid eyes on 
one. It is just my experience that people learn to accommodate the 
apparent  tendency of their paddle to flutter rather quickly, and 
they shouldn't throw the baby out with the bath water.

>PPS - I do get my back up when misquoted.  A couple of times in this thread
>folks have suggested I said that paddles shouldn't flutter.  In fact 
>I have repeated
>that all paddles flutter, but some are better than others.  I 
>apologize if I have
>offended anyone with the apparent sharpness of my responses.

I will plead guilty to not always completely reading the meaning of 
peoples posts and responding to what I thought they were saying 
instead of what they really were saying.
-- 
Nick Schade
Guillemot Kayaks
824 Thompson St
Glastonbury, CT 06033
(860) 659-8847
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From: Michael Daly <michaeldaly_at_rogers.com>
subject: Re: [Paddlewise] Paddle flutter
Date: Sun, 2 Dec 2001 19:13:20 -0500
From: "Erik Sprenne" <sprenne_at_netnitco.net>


> > But the basic blade shape will determine the susceptibility of the
> > paddle to flutter.
> >
> I agree - but also think that any standardized way of
> measuring flutter will also influence the results in some
> way.  Of course, one could then devise a test method biased
> toward the desired results :-)

This is a perennial problem.  Without a standard test, we're nowhere.  With one,
we tend to influence things, sometimes the wrong way.  For example, years ago,
benchmarking computers resulted in computer designers coming up with computers
that excelled at the benchmarks to the exclusion of other things.

Someone (intermittently on this list lately) at a club meeting this past spring predicted   
that in a few years all touring paddlers will be using variations of wing paddles (this
after we agreed that most paddling "standards" are essentially the current fad and prone
to change over time).  In that context, a bias against flutter may be inappropriate, since 
the behavior may be irrelevant in future touring wing paddle design.  

The engineer in me still prefers a standard (terminology or measurements) so we have 
at least some baseline for comparison.   The people just have to learn how to interpret 
the results without "getting religion".  

Mike



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From: John Gibbs <johngibbs_at_charter.net>
subject: Re: [Paddlewise] Paddle flutter
Date: Mon, 3 Dec 2001 16:50:51 -0500
Thanks again to all for the analysis of flutter. It looks like I'm stuck
with this beautiful, light, fluttery Swift paddle, as I took the word of the
Pacific Wave sales rep over the phone regarding returns, but have now
learned of their unposted policy of no tested equipment being returnable. So
I'll follow the lines of counsel here pertaining to the paddler, continue to
play with technique consciously and un, and report back if this paddle
stablizes. If the flutter isn't resolvable in my hands, perhaps I'll find
someone who's dying to swap.

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From: Alder Creek Kayak & Canoe <aldercreek_at_qwest.net>
subject: Re: [Paddlewise] Paddle flutter
Date: Mon, 3 Dec 2001 14:34:39 -0800
word of the
> Pacific Wave sales rep over the phone regarding returns, but have now
> learned of their unposted policy of no tested equipment being returnable.


Yikes.  If you really don't like the paddle, tested or not, they should take
it back.  We would.  In fact, if it's in new condition, I''ll trade you for
sumthin' we have in stock.   We sell Swift so it's a win/win. where are you
at?

Steve
Alder Creek Kayak & Canoe    N   45º 39' 47"
250 NE Tomahawk Isle Dr.     W 122º 36' 16"
Portland, OR  97217          Web: www.aldercreek.com
Phone: 503.285.0464        Email: aldercreek_at_qwest.net



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