Walter & Group....
From Peter Lami :
Gordy,
I have a lot
of fun amusing myself when I’m giving a fly casting lesson in Piedmont Park
doing these kinds of pickups on the grass ... Truthfully, I’m just showing off
but I don’t say anything to my student. Unless, the student is a Master
Candidate. What strikes me about this threaded message is how you have
changed the context from a “Change of Direction Cast” to a “Pickup”. I
think I could find it in my heart to forgive a candidate if this seems
confusing. Which is it, change of direction or
pickup?
Peter
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Peter: No problem. ITS BOTH !
In the case of the change of direction made by pointing your rod at the new target and making your back cast from it and then your forward cast to it, you are making the change of direction on the back cast pick-up.
Different from the "Wye cast" where you pick-up from the first target, make your back cast directly 180 degrees from it, then turn and make your forward cast to the new target. Here it is a change of direction made on the forward cast.... not from the initial pick-up. (Actually the change of direction is begun just prior to the forward cast during pause time.)
Gordy
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From Gary Davison.... a fresh look at pick-ups from a Spey casting standpoint :
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Hi Gordy
With regards to pick up's I like to think of these for the purpose
intended. In Spey Casting we break these down into two
categories. These are made based on the intent of the cast being
made.
Airborne pick ups: This is where the
line is picked up off the waters surface and suspended in
the air to make the cast.
Examples: Straight line, Snake Roll, Single Spey, Switch Cast,
Spiral, Belgium, to name a few.
Generally speaking most of these casts will require constant
tension on the line to be preformed. Usually the line is suspended in
the air throughout the cast, or you have what we call a splash and go type
of effect where line hits the water for a very brief time, and then
sent to the intended target. Great thing about these pickup's and
casts are that they create very little disturbance on the
water when making the cast. Very good pickup's and casts, when
you are working fish that tend to have spooky natures.
Get's the line off the water in the air fast to make the cast, plus allows
great change of direction when needed. Of course based on the
variety of casts available to us. We can create any combination needed to
address the fishing conditions. Meaning introducing slack
line or other elements when and where needed during the casting
sequence. That is why it is important to know the cause and affects
of the essentials to met the challenges we face. Important thing to remember as an instructor is
to never stop learning, it is a continuous process for all of
us!
Waterborne pick ups: This is where the lines
are pulled to, or picked up, for placement in the water to
make the cast.
Examples: Roll cast, Double Spey, Snap T or Z, Skagit Circle
Spey, Skagit Double Spey, and Perry Poke to name a few.
Generally speaking most of these cast will require the line to be
moved into position on the waters surface in order to make the
cast. The pickup is made to position the line in the
correct location by the caster who is either in the water or on the
bank. Water tension acting on the line is usually the
means of loading the rod in order to make the cast. Also
these type of pickup's and cast's, do create more disturbance on the
waters surface. So we usually do not use these when around those
fish that are spooky in nature. However this will depend on the
fishing conditions. I would add that an exception on the list, would
probably be a roll cast, being as the line is pulled into
position slowly and the cast is made with a minimum amount
of water disturbance. However this will basically depend on the
amount of line staged on the waters surface when make the
cast.
All the best
Gary Davison
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Gary... I like to look at
pick-ups from a stand point of intended purpose, even with single handed
"straight line" casting. The basic purpose there being to pick up the line
for an efficient back cast without diminishing available stroke length and
rod arc as the caster gets the end of the line
moving.
Secondary purposes include the avoidence
of line catching or being resisted by tall grass (dancing line pickup) or
lilly pads (wiggle pickup), etc., etc. Some other purposes include
picking up line which has sunk (multiple roll pickup) or line which is out
there with lots of slack ( C-pickup, etc.).
Gordy
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MORE ON DRAG INDUCED LIFT
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Al Crise sent us this from Caroll Hall of
his Group :
Howdy Gordy and Bruce
This is from Carroll one of my CCI Candidates that also happens to
enjoy the Engineering standpoint of the fly Cast.
ol Al
---------- Forwarded message ----------
From: Carroll Hall <carrayhall@xxxxxxx> Date: Sun, May 10, 2009 at 12:35 PM Subject: the missing force To: allen crise <oldflysoup@xxxxxxxxx> Al (and please forward to Bruce
Richards for comment)
I finally figured out what was missing in my understanding of the
forces acting on a good cast to retard its fall. In our previous
communications, we had identified all the forces necessary except a
vertical force acting on the fly leg to counter gravity.
I now think that in addition to "drag induced lift" on the loop
front, another "drag induced lift" acts along the entire length of line
identifiable at any particular moment in the cast as the fly leg.
For this theory to be the case, the fly leg would have to fall off
from the loop front at a slight angle below horizontal (or the plane of
the cast if not horizontal.) An equilibrium between lift and gravity
would be created at each point along the fly leg.
* When the angle of a line segment
containing a particular point is too small, gravity would adjust
downward.
* If the angle were to fall off too much
below the horizontal, lift would adjust upward.
This stable angular configuration of the line would set up as a wave
rapidly propagating down the fly leg starting near the loop front.
This configuration also depends on the upward vertical force exerted
on a very small portion of the fly leg at the loop front.
There is of course no drag induced lift on the rod leg since it has
no velocity. As previously discussed, the rod leg depends on
horizontal tension and vertical support from the rod tip on one end and
drag induced lift at the loop front on the other end.
It seems to me that the rate of fall for all the line in a back or
forward cast would be about the same and primarily determined by the rate
of fall of the loop front. This conclusion is due to both fly leg
and rod leg depending on vertical forces originating from the "drag
induced lift" in the loop front. The fall of the loop front could be
determined by subtracting the lift from the gravitational pull.
Regarding a different but now relatable subject: After thinking about
the preceding, it also occurred to me that "drag induced lift" acts on the
entire fly line during the time interval between the initial pick-up and
the creation of the fly leg. Immediately after initial pick up, the
fly line extends downward from the rod tip at a rather steep angle from
horizontal. This steep angle contributes substantially to "drag
induced lift" as the line velocity increases. For a good cast, it
doesn't seem to take much time for the line to become nearly horizontal.
This may be fairly difficult for one to observe in their own cast
but easy to imply as one observes a horizontal fly leg appearing in their
backcast. The earlier description of fly leg lift is to some degree
a continuation of a lifting process that began immediately after the
pick-up. The main difference occurs in the transition from the rod
tip to the loop front as a source of vertical support.
Thanks for your time entertaining my comments. This discussion
of "drag induced lift" has added considerably to my understanding of fly
line behavior during a cast.
Carroll
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Comment:
Interesting thoughts by Carroll
! Question is whether or not enough drag induced lift could be
produced along the fly leg to be significant in keeping the line
aloft.
My thoughts:
1.) Carroll has wisely applied this
to a simple cast where no line is shot, therefore we can ignore the effect
on the rod leg because it has no velocity. (She pointed this
out.)
2.) The forward travel of
the fly leg of the loop is in the direction of its own vector. Thus it
would seem to me that very little air resistance would be encountered
compared with that of the leading edge of the loop. However, it can
"ride on the air" and thus remain aloft longer than it would if moving at
the same velocity out in space with no atmosphere.
3.) Its downward velocity
(due mainly to the effect of gravity) has been calculated in
terms of its rate of fall by Noel Perkins. It is so small as to
likely engender very little atmospheric resistance leaving open to
discovery the amount of drag let alone drag induced lift. This
especially in light of the calculations showing that the drag induced lift
is directly related to the square of the velocity.
4.) Her point about the
continuation of lift force from shortly after pick-up
compared with the transfer of lift force after loop formation is thought
provoking. I hadn't considered drag induced lift applying prior to
loop formation.
Gordy
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From Bruce
Richards:
Thanks Al, Carroll is pretty much right on. The top leg is travelling quite fast. Much like holding a length of fly line outside a fast moving car, the force if the air on the underside of the line as it tries to fall will hold it at an "equilibrium angle". The higher the line speed, the more perpendicular that will be with the direction in which gravity is pulling. Bruce Scientific Anglers/3M ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
From Bob Tabbert: Hi Gordy, it seems that the discussion of 'lift' on a fly line has a life of its own. Take a look at the bottom of page 34 of the May/June 2009 issue of American Angler. Bruce Richard is quoted: 'And as the fly line tries to push itself down, form drag tries to force it back up. Thus the major forces acting on a line are both back and up. We call that lift' Off to the Gulf Coast Council's Conclave in Lake Cahrlesm, LA this weekend, will be working as a casting coach, Bob
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