Fly Casting- The Anchor does Not load the rod.


when talking about rolls or Spey casts how many times have you heard that it does or that we load the rod against the anchor ?
probably many, many, many but all those manys are wrong because the anchor can not load the rod, it’s as simple as that. let’s see why this beastie doesn’t have any magical properties, its real role and why we use it.

because slomo videos don’t lie and have the wonderful habit of debunking myths here are two eye-opening videos from Aitor Coteron with a few words first to guide you along.
– firstly, take note of the equipment and location used for this demonstration. the rod is an Echo MicroPracticeRod with its synthetic rope and yarn line and the hallway’s floor is like most hallway floors; super-slick.
in other words, the rope/yarn/floor combination offers so little grip that it’s almost irrelevant to bring up any notion of a ‘real’ anchor. i’m a dummy when it comes to physics but the only conceivable ‘anchor’ i can think of in this particular case would be gravity’s effect on the yarn and considering its mass that can’t amount to much.
i can’t put any figures to this but let’s just say that an equivalent anchor on water and its subsequent surface tension gripping qualities would be hundreds or maybe thousands of times more than this kit on this floor yet the cast works perfectly.

– as noted in the video, we’ll easily see that the anchor doesn’t move until the rod is already fully loaded and if it isn’t moving it’s because there’s no tension on it: it’s not being pulled.
if we where loading the rod against the tension of the anchor, line tension would need to start and continually increase before the rod could start to bend.
line tension is gained and the fly leg only seriously starts to move backwards in the direction of the D-loop once the cast is completed.

now that that’s done and over with and hopefully the notion that the anchor loads the rod is wiped from the slate for good, let’s consider what the anchor actually does when we’re on the water and why we need it.

the anchor’s functions are twofold and interrelate. it prevents the line end/leader/fly combo from swinging back behind the caster where it might snag something or someone while simultaneously allowing a more efficient cast because there’s a loss of line energy efficiency if part of that energy is going in the opposite direction of the intended cast. in other words, we’re pulling the line in one direction (forward) but part of that line needs to go in the opposite direction (backward) before it can turn around and go towards our target and that’s no good.
when performed on water, even if there’s a very slight reversal of the line end going backwards towards the D-loop it’s negligible compared to a slick surface. (we see this on slomo video analysis, it’s not impossible but not so hard to see this slight reversal on water with the naked eye if we look carefully)

just to give another perspective to the smooth-floor casts here’s another sample filmed from the side.

ok, with that said we’re left with the obvious question: what am i loading the rod against if it isn’t the anchor ?
well, that’s easy. it’s exactly the same principle as when we’re doing aerial casts, we’re loading the rod against the combination of the rod itself (its actual physical weight and swing weight ) and the weight of the line outside of the rod tip except for one difference, with rolls and Speys the effective line weight we’ll be using isn’t all of the line outside the rod tip but only the rod leg- A and B through C. the fly leg- C to D doesn’t contribute significantly to the loading process.
here’s further clarification on this last point from Aitor:
“Just another common misunderstanding is that the anchor + fly leg of the D loop don’t load the rod because there is very little mass in that part. That isn’t the reason. The fly leg doesn’t load the rod because it isn’t accelerated by our stroke: no acceleration = no force; no action on the fly leg = no reaction from it on the rod.”
from the second video above Side View “See how the anchor starts sliding when the stroke is almost finished. And this even on a polished floor and with a very short line between loop apex and “fly”. If the anchor doesn’t move is because nothing is pulling it.”Spey D-Loop & Anchor
the anchor D to E is disregarded which goes to explain why we don’t take into account the weight of sink tips when we’re figuring out line weights for Skagit or other shooting head line systems.
having most of the weight near the rod tip A to C also explains the typical profile of just about every Spey line there is.

and here, the very significant contribution by Grunde Lovoll.
“in another discussion on Aitors wall I was challenged to elaborate on
this statement:
“The main benefit of the anchor is preventing the fly leg from going
“backwards”. _That_ effect actually lowers rod load, since greater
velocity difference in fly- and rod-leg would result in more line
The statement above has two claims about anchors in
roll-/spey-casting (from now on spey-casting).
1) The main benefit of the anchor is that it “stops” the fly-leg from
going backwards (i.e. in the opposite direction of the cast being
2) In roll casting a slipping anchor will in fact give higher line
tension in the loop than a static anchor, and thus more rod loading.
Before I explain these two claims I would like take a step back and
talk about line tension and rod loading. Frankly I think that the
focus on rod load is causing a lot of confusion and it is anchored
(pun intended) on the “false believe” that the main driver in casting
is the rod giving back potential energy when it unloads. This may
explain why people think the anchor is responsible for rod load; a
slipping-, crashed-, skew-, misplaced-, whatever-anchor is indeed bad
for your cast; therefore the conclusion is that it also is crucial for
rod loading (which we all know is complete and utter bullshit, yeah
English is also my second language).
Now we also know that what’s loading the rod is line tension. This is
off course also correct (ignoring self loading, air resistance and
gravity), but what isn’t correct is that the tension is the same along
the whole line. This is only correct in some static cases, if the line
(or parts of the line) is accelerated the load is not the same along
the line. In the D loop of a spey-cast the tension is highest at the
rod tip and decreases as we move (along the rod leg) towards the loop
(because the line pulls on less and less accelerated mass). The
tension in the loop itself is caused by the moving rod leg, and it is
given by the momentum change in the loop. Change in momentum as the
line is accelerated from fly- to rod-leg. It can be shown that the
tension in the loop is proportional to the velocity difference of the
fly and rod leg. So as the speed of the rod leg increases the tension
in the loop also increases. This tension from the loop then pulls on
the fly-leg, and the higher tension from the loop, the higher will the
acceleration of the fly leg be.
Now we can discuss the initial two claims.
1) The purpose of the forward stroke is to get enough inertia/energy
into the rod leg so that it is able to lift the fly-leg up and forward
and still have enough energy to unroll the line and get it nice and
straight. Any line mass moving in the opposite direction is therefore
bad for the cast as it takes energy out of the cast.
2) This statement is in essence explained above. The tension in the
loop is proportional to the speed difference between the fly- and
rod-leg. A slipping anchor gives higher speed (in the opposite
direction) of the fly leg. Thus higher tension in the loop and higher
tension in the rod leg. Now; this effect is probably very small, since
the tension in the loop is small, and any benefit on rod loading is
canceled by the backwards moving fly-leg.
All in all the tension in the fly-leg is quite small in all
spey-casting, and focusing on it and how it affects rod loading is
therefore quite a diversion for understanding what actually goes on in
spey casting. Also; Aitor has brilliantly demonstrated exactly this
in many of his casting videos, so nothing new here… “

and that’s about it !  if you’re still sceptical about the anchor thing go out and try this slick floor experiment for yourself with your standard rod and line, it’s a no-brainer.
to add to that you could always consider that although not exclusively, many of the International Federation of Fly Fishers casting instructor exams are performed on grass and the roll and Spey tasks may be done there as well. i and many of my colleagues have done both the basic instructor and master level exam without water and have performed spot-on rolls and Speys without a ‘proper’ anchor. why so many have passed their exams on grass and continue to ascertain that the anchor loads the rod is beyond me… but that’s another story i guess.

33 thoughts on “Fly Casting- The Anchor does Not load the rod.

  1. Hi Marc,

    Looking at the diagram. Only part of the line from C to D can actually load the rod: that part being accelerated during the stroke. The rest does nothing in that regard.

    • hi ! and thanks for you input. i understand that C to D is accelerated but don’t understand that A to C isn’t (if that’s what you’re saying)
      could you explain that please ?

      • Only the section of line being accelerated contributes to rod loading: A to C and the part of C to D which we move during the stroke.

        This could also be of interest:

        • ok, thanks a lot ! i was under the impression that the fly leg of the D-loop had a lesser contribution (for lack of a better word) in helping to load the rod than the rod leg because its generally lighter/has a lower mass.
          thanks again for all your eye-opening videos. they’ve gone a looooooong way in explaining how all this works and i’m looking forward to more. 😎

  2. the role of the anchor is to add friction. Will not load. Only the hanging mass will load the rod. The roll of the mass/line is to deliver the energy in cast. We have two energy’s combined, one from loading mass and one received from caster. 🙂
    The anchor have a role in cast but not to load the rod

  3. Hi Marc, like always I love your site and info that you share ! I hate staying in office but in couple of months I will return in Romania and I will have time for fishing and casting 🙂 I miss them a lot 🙂

  4. thanks Aerto ! 😆
    since i’m not a member the forum won’t let me read the last pages so i’m missing out on something that must apparently be grand ?
    two observations:
    – that forum (and not just the casting section) is just….. i don’t know what or rather, would prefer not to say it in public.
    – hopefully someone will put that Darren guy out of his misery soon. 😎

      • i did a while back Lasse. the more i read and commented, the more my butt cheeks started being tense so i promptly left ! 😆
        but seriously, it’s a miserable place like just about every single fly fishing forum now. we have a certain amount of experience in varied fly fishing domains and can sift through the interesting or not interesting or downright crap but i feel really sorry for the novice who wants to learn something and goes there for help. as Aitor wrote above, these places can be of interest for studying human nature (bad human nature) and nothing more. no thanks.

  5. […] last weekend was spent in the Basque region of Navarra, Spain with friend, casting instructor colleague and someone i could consider to be my mentor in these fly casting shenanigans, Carlos Azpilicueta. this fronton, apart from being indoors protecting us from all the weathery crap had two distinctive features that made it all the more special and productive and they where both on the floor. first, the surface was incredibly slick (not slippery as in sliding and falling over when moving about but in the sense that the fly line had much less grip than field or artificial grass might give). this made for a perfect manner to study, observe and demonstrate the effects of the anchor for roll casts and Speys by effectively removing the anchor from the equation while still getting good casts. not only that but it was yet another perfect way to demonstrate and disprove the too often common notion, that the anchor loads the rod. (it doesn’t because it can’t. more on that HERE) […]

leave a reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s