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Hi,
All...
As I stated
before, to me the first draft is clear.
Jason... re.
the physiological action which can allow the rod to unload is
what the average caster feels to be a true STOP. So now we
need to look at what STOP is.
It can be
total, instantaneous cessation of movement. This isn't it with the fly
cast, because no human being can achieve that.
Can it be
sudden reversal of the direction of applied force ? Theoretically so, but
despite the caster's synaptic attempt to use his antagonist muscles to do that,
I doubt it has a significant effect.
Can it be the
act of ceasing to accelerate ? I think Server may be correct in that this
is the only thing really needed to have the rod unload.
If so, can
this be called "DECELERATION" ? ... or "NEGATIVE ACCELERATION" ?
.... I'm not qualified to say.
I believe it
was Walter who pointed out that the casting hand is necessary during rod unload
to provide a stable platform for the fly rod. This makes sense to
me.
His concept
of "launch point" also makes sense.
So as the
casting hand slows and holds (which some will call the "stop"), the very act of
doing this can, I think, provide stability for the rod and control of
trajectory.
To simply
state that "there is no such thing as a stop" or even that "the stop is of no
value" will be met with great resistance. Reasons
?
1.) Because
it is a simple fact of life that most instructors find that teaching the casting
student to STOP is effective in yielding more efficient
casts.
2.) In
the cited study, the elite casters had more efficient casts when they had
crisper stops. Was this because the rod unloaded differently or with more
energy ? Probably not.... rather that the STOP yielded better
control.
Just my 2
cents !
Gordy
Okay - here is what we have for a first draft. We
shall add you as a co-author on the next draft.
As I say it concentrates on just the idea that
you don't have to physically stop the rod for
it to unload
because I think that is going to be a difficult
concept for people to buy in to.
Where do I think that leads to? I think every
serious caster reaches a point where they see advanced
casters like yourself ending their backcast with
the rod nearly horizontal but the line still goes where
the caster wants it to. So they realize that the
basic principle of physically stopping the rod is being
violated but they don't understand the mechanics.
Some people will experiment and come up with
it on their own. Others will be unlucky enough to
be spotted by a casting instructor whose sworn
duty will be to get them making the "correct"
stops again. Others will be even unluckier and get a
casting lesson from Paul Arden and end up with a
torn rotator cuff :-P~~ :)
I think it's kind of like telling a beginner not
to use their wrist when casting. The hope is that they
will just bend it a little bit and someday when
they are ready for it they will be given the keys to the
magic kingdom of casting (right next to Epcot
center I believe) and told that rotation is necessary
for casting - it just has to be controlled. So we
will still teach beginners to physically stop the rod
because this is the easiest way for them to make
nice controlled loops. But when we see someone
who is trying to make the next step - smooth
transition to layback or drift - we will explain the
mechanics of unloading without a physical stop
and save them a lot of time and effort and possibly
physical injury.
This means that we would have to define stop in
terms of rod load/unload - which could mean a physical,
hard stop but could also mean just not applying
force.
The physiology/physics concept is a good one and
one I would certainly like to explore further.
Looking forward to the pics!
Thanks for taking the time on this.
Walter
----- Original Message -----
Sent: Friday, April 24, 2009 3:53
PM
Subject: Re: Want to pick your brain on
a few things... (PART2)
Walter--Okay, here's the "part 2"...
(In relation to our last, short emails and "hard stop")--I have been
viewing the idea of "hard stop" more and more from the view-point of getting
people to accelerate better (versus "soft stop"--and I'm not looking at 170
casts, here, foundation stuff), as well as an aiming device, not an energy
transfer device. And yes, what exactly is a "hard stop," really? Again, I
see the idea as related to what happens *before* unload--better accel, not
wishy washy rod movement. Okay, onto the original email...
Rod unload and all that:
I also
agree that once you reach the "rotational peak" so to speak, you can't do
much from there! Either that rod begins to unload, or we pull a "superman"
and re-load it again (that could get ugly, too!). I also see what I would
think are second-node stuff in some of my "stops" (s-wave in the rod)--will
you all be looking that too, since it seems to indicate very rapid slowing,
or even reversal of the butt very near RSP. I'll get you a pic or two
ASAP.
I know that
I can control the direction of the rod and line, and can control (at least
it seems to me) the point at which I reach peak accel, but beyond that, it
definitely seems to me, and the mo-cap, and the 500fps cam, that the rod is
doing its thing and we are only providing a minimal amount of
adjustment/additional rotation in that very short time period (thinking MAV
through MCF or so). This was shown (I thought) pretty well in The Rod and
the Cast paper, along with supporting video, so that may help support your
work, too.
I would
definitely be interested in what you all are doing, and perhaps being able
to be involved in some way (in fact, I was going to call Server anyway, and
I haven't yet. If you talk to him, let him know that I will). I think the
key issue here is going to the idea of what the stop is (both the
conventional idea of screeching the rod butt to a stop (actual reversal of
accel?) and the idea of the change in the rate of accel (transitioning
through constant to slowing), and how we initiate it physiologically.
That last part, is, I think, the key to getting people to both understand
and perhaps accept some of this (and seeing a 170 cast made with no "stop",
yet the loop is aimed precisely and not into the ground). I have very
clearly seen the caster and rod in action in short, medium and long casts at
all sorts of frame rates, just like you and Server. And I think we can all
speak to each other in ways that can make sense as a result of some of that,
but others may have some trouble thinking through what's happening
physically.
To play
devil's advocate, I'd first ask how physiological actions enact rod
unload--the rod doesn't move our hand through the loading portion of the
stroke (although I think we could have some pretty interesting discussions
about the unload portion and forces from the rod, but that's another idea).
We move the rod, and we direct it, otherwise we'd never be able to alter its
aim or path or have any say at all over loop dimensions (And yeah, we can
also adjust loop size post-cast with swoop/bounce-through, lift, pull-back,
etc., but I am talking about the physiological picture inside the
stroke proper (all the way through through MCF). Do you get what I mean
there? We may not typically be able to apply force in a reverse direction
during unload (the "hard stop" as it were), but at some point our bodies
either reach a point at which they can't sustain accel of the rod butt any
longer (something I've been thinking a lot about with range-of-motion, by
the way), or we have to "tell" our body to move a certain way so that the
line will be directed toward a certain spot . That requires the rod to begin
the unload process to send the line in the desired direction, so we need to
be able to link the physiological to the physics (and perhaps Grunde can
also help here, too).
All that
said, getting rid of the term "stop" could be an uphill battle that would
not be pretty in the least (and probably counterproductive, since it "makes
sense" to so many students). If the goal is to at least intro "alternate
terms," what are they?
So...I'm
interested in seeing what you guys are up to, and finding out what the
thought-process is, and how it can "jive" with current terminology (or
not).
Hit
me.
Jason
On Apr 15, 2009, at 12:13 PM, Walter Simbirski wrote:
Jason,
Server, Gordy Hill, and I are working
together to try and capture Server's ideas for a paper
on casting mechanics. Initially the paper
will be presented to Gordy's study group but
who knows where it will go from there. I know
a couple of people who will probably be using
it in place of toilet paper :)
The gist of what we want to talk about is the
concept that it is necessary to stop the rod
in order to unload it and to get efficient
transfer of energy to the line. The quicker the stop
the better the energy transfer would be
"conventional" wisdom.
Server has pointed out that stopping the rod
has nothing to do with unloading the rod and,
therefore, has nothing to do with efficient
energy transfer. The reality is that once the rod
is loaded there is virtually nothing you can
do to prevent the rod from unloading (assuming
a "normal" casting stroke). Also there is no
reason why the rod has to be physically stopped
in order to unload. As long as we are
applying force to accelerate the rod it will bend. Once
we are no longer accelerating the rod it will
unload.
The thing to remember here is that no
acceleration does not mean no velocity or no movement of the
rod. Once the rod tip reaches 100 miles per
hour it can continue at 100 miles per hour and the amount
of force required to keep it moving at 100
miles per hour is just the amount of force to balance air
resistance
which is minimal. What this means is that at
this point there is nothing we can do to prevent the
rod from unloading (unless we have some near
super human ability to start accelerating it again).
It's going to unload whether we continue it
moving at 100 miles per hour or we come to a dead stop.
The amount of energy the rod transfers to the
line during the unloading phase has nothing to do with
whether we continue on at 100 miles per hour
or come to a dead stop. The things we can do at this
point are to provide a firm base for the rod
to unload against (by keeping a firm grip and with muscle
tension) and to control the path of the rod
tip so that as the rod unloads the tip pulls the line in the
same
direction it has been pulling up to that
point and then gets out of the way so a loop can form.
A couple of years ago I was fortunate enough
to be in one of your classes at the conclave. During your
description and demonstration of the stop you
asked us to look for the stop in your back cast. There
was no discernable stop until the rod came to
rest at a near horizontal position. In the mean time the
rod had obviously unloaded in the
classic 1 o'clock position. If I recall properly you explained
by
saying that the stop was there it was just
that advanced casters are able to stop, causing the rod to
unload, and then follow through so quickly
and smoothly that it was almost impossible to see. Based on
the discussion in the previous paragraph I
think it is more likely that you took actions to cause a
quick
and efficient rod unload (this would mean
firming your grip and transitioning from high acceleration to
constant velocity (zero acceleration)) and
then following through from there without a momentary stop.
The other reason I think about you in this
discussion is that the work you did together with Grunde
Lovoll
would support the idea of a stop being a stoppage of acceleration only
rather than a hard physical stop.
So this brings up a couple of
questions:
Does the idea that a hard physical stop is
not required make sense to you?
Would you be opposed to our using some of the
information from the paper you and Grunde did?
Would you want to be involved in what we are
doing at some level?
And more importantly - Are we going to have a
chance to fish together this summer? Some place in Washington
state or Oregon? I prefer not BC because I
don't want to mortgage my house for a daily non-resident
licence.
I just saw your question about capturing
video from the videolyzer on your web site - this could be a
good
place/time to do that. We are still undecided
about the conclave this year so that probably isn't a
possibility.
Any way...
Cheers!
Walter
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