[Irvine Ross]

See Rio's lines on their website, the THE TOTAL WEIGHT OF OF THE HEADOF A LONG BELLY WILL BE MORE THAN THE TOTAL WEIGHT OF HEAD FOR A SHORT BELLY THAT WILL WORK THE SAME ROD!  Think about it Rob.......

Cheers
Ben

Ben

I don't get this either. Tell me where I am wrong.

A rod rated for a #10 line is designed to feel loaded with 30' of "standard" fly line outside the rod tip when overhead casting. However when you are Spey casting and form a D loop, half the weight of the head is lying on the water so it is only the half of the head nearer the running line that is loading the rod. Therefore a 60' Spey head could be double the weight of the "standard" 30' head and the rod will still be loaded as we are only casting half the head. I'm ignoring compound tapers hear for the sake of simplicity.

So, with a Powerspey with the whole head out we are effectively casting 425 grains (half of the full head weight of 850) and the rod feels loaded. With an AFS with the whole head out we are effectively casting 320 grains (half of the full head weight of 640). This is only 75% of the weight of the Powerspey so how can the rod feel equally loaded?

The only explanation I can figure out for myself is that the tapers are radically different and the AFS has 425 grains in the lower part of the head and only 215 grains in the first half of the head.

 

Irvine

[Loxiafan]

However when you are Spey casting and form a D loop, half the weight of the head is lying on the water so it is only the half of the head nearer the running line that is loading the rod.

My knowledge of casting is mince so forgive me if I am way off but is the "pick up" from the water not the first loading move on the rod tip, therefore the weight of the anchored line and it's relative drag on the water that would still have a loading effect ?

All very interesting so looking to be enlightened !

Lindsay

[Ben Dixon]

Ok, because I am presuming that to cast, the whole head needs to be out the tip ring...so a longer, heavier head will load a rod more than a shorter, lighter line, when all the head is out, because it is in the air, not laying on the water.

If you are talking about only the first 30 feet, then yes, I can see how it would work.

Hi Rob,

The AFTMA number refers only to the first 30' of a line and gives no description of what happens after that point.  We will have to accept here that there is no rod rating system, rod manufacturers will make a rod and it will be assigned a line rating based upon what they think it casts well for the application in which they intend it to be used. 

Forget Spey casts for a minute and think about a DT7 single handed line and overhead cast where the length of line concerned is aerialised and straightened out behind the rod as it would be if we had just made a back cast, we are not shooting line to reach our target or hauling.

So, we have 30' of DT7 line weighing 185 grains in the air behind the rod which we will deliver to our target say a trout on a still water.  Fish doesn't take the fly, it has moved 10' further out, this time we aerialise 40' of line.  The total weight of line in the air has increased, it has to as we have increased the length of line. Does it still work your #7 rated rod that casts nicely with exactly 185 grains at 30'?  I'd expect so.  The rod will bend a little more as we're accelerating it against a little more mass but that's fine, we just increase the stroke length and arc a bit during the cast.

What would happen if we decided that the rod needed 185 grains period and would not cast anything else but we still needed to aerialise 40' of line? To accomplish this we would have to put on a DT5.  Fish has moved another 10' from us so we'd need to put on approx DT3.5 to be casting approx 185 grains.  185 grains stretched over 50' is going to feel very very light, it will feel a lot lighter than 185 grains at 30' and we are going to have to move the rod very quickly to get the same bend in the rod.
If we were consistently fishing with 50' out of the tip we may go down a line size to a DT6 but 50' of line weighing 185 grains

Then look at it the other way, we aerialise 10' of line that weighs 185 grains, that's about a 15wt line.  How do you think that would feel as we increased it at 10' increments longer than that?  Again, if consistently fishing at less than 30' we could possibly go up a line size or two but we would not always want to keep the mass of line to 185 grains regardless of length.

Does that make more sense?

Cheers

Ben

[Rob Brownfield]

Hi Ben,
Many thanks for the reply.

I think we are now talking about two different things  .

The question came about because you stated that the Elixor was a shorter line than the Barrio Switch, and therefore lighter. I can understand that after your first ecplaination, but then somehow we got onto OH casting and it appeared you were suggesting that the same principle applied as you started to talk about the SA line and head length etc. Perhaps I picked that up wrong?

I fully understand your latest post, those principles have never been in doubt in my mind and I have used lighter DT lines on heavier rods in the past to get extra distance. (Before WF lines were that popular or indeed really understood..lol)

Anyway, useful information for everyone, many thanks.

[Ben Dixon]

Hi Rob,

What I hoped you'd get from the above is that for a given rod, a longer line for that rod needs to have more weight to feel "right" when casting (to a point) than a medium length of line on the same rod or a short line on the same rod.  Therefore, it should follow that, in the case of WF lines (or shooting heads) where we are casting generally the whole head, that a short head for a given rod must weigh less than a long head for the same rod.  This explains the difference in weights between the Elixir and the Barrio switch lines.

Whether we are talking about Spey casting here is really irrelevant.  We are still casting a length of line with a flexible lever, the same principles generally hold for Spey or overhead casts, it's just easier to visualise a straght length of line behind the tip rather than a D loop.  How much mass is effectively levered by the rod during the stroke will change slightly for a Spey cast but that is really a different topic.

Cheers

Ben

[Marc Fauvet]

Whether we are talking about Spey casting here is really irrelevant.  We are still casting a length of line with a flexible lever, the same principles generally hold for Spey or overhead casts, it's just easier to visualise a straght length of line behind the tip rather than a D loop. 

 

[Marc Fauvet]

My knowledge of casting is mince so forgive me if I am way off but is the "pick up" from the water not the first loading move on the rod tip, therefore the weight of the anchored line and it's relative drag on the water that would still have a loading effect ?

Lindsay

hey Lindsay,
that's a very common misconception (but don't worry, it's the kind of thing that's repeated ad nauseum all over the place even though it's false)

A to B, (the D loop) is the weight we are applying force against (combined with the caster's movement and rod weight)  to bend/load the rod for the forward roll. we don't load against the anchor, it's just there to keep the line tip/leader to swing backwards during the forward stroke.
the best and most simple test to have a once and for all confirmed view of this is to do a roll cast on a smooth dry surface. there  is no real anchor because there isn't water tension to hold the line but the rod is perfectly loaded and the cast still works. (it's not ideal but it's to prove a point)
watch this
http://vimeo.com/aitorc/anchor-and-loading
cheers,
marc

[Loxiafan]

Thanks Marc, totally get it there with a Spey/Roll, but that wouldn't be the case in a conventional 'pick-up' where we are actually plucking/lifting the leader and line from the water as in a side or overhead cast would it ? Or would it ! 

Cheers,

Lindsay

[Marc Fauvet]

Thanks Marc, totally get it there with a Spey/Roll, but that wouldn't be the case in a conventional 'pick-up' where we are actually plucking/lifting the leader and line from the water as in a side or overhead cast would it ? Or would it !  

Cheers,

Lindsay

hi Lindsay,
that's the 'lift', this is how a lot of us like to consider this part.
from the SexyLoops Fly Casting Model - Core definitions http://www.sexyloops.com/flycasting/definitions2.shtml

Lift: An upward Sweep.
The primary purpose of Lift is to begin to clear line from the water prior to a further line positioning movement or Casting Stroke.

as such, it's not included in the casting stroke (or what some refer to as 'the loading move')
sure, the rod is bending but only a little. definitely not what we can consider 'loaded' and definitely not enough to cast the line past the rod tip and form a loop.

have a good look at the link above and don't hesitate if some things aren't clear.
hope this helps,
marc

[Ben Dixon]

Hi Marc,

IMO, the diagram you posted only really holds for short heads and even then I'm dubious about the position of point B.  If you look at high speed stills of a Spey with a long belly, the rod has often hit RSP1 (straightened at the end of the forward cast) and the leader has not moved.  I would say point B is, in many cases, closer to the apex of the D loop although I am fully prepared to be convinced otherwise.

Agree 100% about the anchor, it is simply there to provide tension and hold the front end of the line in place until it is picked up by the back end of the head and carried into the top leg of the forward loop.
Having no anchor is in effect just like making an over head forward cast before the back cast has fully straightend.

Cheers

Ben

[Marc Fauvet]

hey Ben !
yup, by looking at the rod/line proportions it's already quite obvious that it's a very, very short line 
(that's from Rio's spey chart btw)
sure, there's too many variables: kit, caster abilities, conditions etc, etc to establish absolutes but my point was to simply show the part of the line we're using to 'load the rod' and to differentiate it from the anchor. yes, it's a rough drawing but for that purpose the drawing works well.

cheers,
marc

[Loxiafan]

Cheers Marc, will check that out 

Lindsay

[Ben Dixon]

(that's from Rio's spey chart btw)

Yup, I know 

Away to make my own!

[Marc Fauvet]

here's another one i just found that looks a little better.

[Marc Fauvet]

ooops.... that's me trying out some of Steve (Cookshills) fresh seal's fur... 

here's the D-Loop/Anchor  diagram