Monday 29 April 2013

Half the System - Thinking about Lines

(I have updated this post to reflect the development of new lines since the original)

As the third generation of salmon anglers in my family, I have never been short of wisdom handed down by my father and grandfather.  In his youth before World War I my grandfather fished the Ure in Wensleydale; and in his latter years the Exe and Torridge in Devon, accompanied by my father.  As Yorkshiremen they were not short of opinions or the readiness to express them.  One of their enduring aphorisms was "buy the best line you can possibly afford".  I have always followed that advice and it has stood me in good stead.  Skimping on the line really is a false economy and carries a high risk of deep disappointment.  I watched three of my friends fall into that trap and pay the penalties in degraded casting performance, frustration and fatigue, followed by buying a good line at a sensible price.

Since my forebears' time rod and line technology and performance have advanced almost beyond recognition.  Plastic lines arrived in my grandfather's seventies along with glassfibre rods.  If anything the rate of advance has accelerated in the past decade, but one of the consequences is that novices are confronted with a bewildering array of choices, names, brands, descriptions and jargon.  The purpose of this post is to offer a few simple signposts through the confusion.  Again, I won't be saying Brand A is better than B, because I haven't tried them all; I only know what I use (Rio); and I have no desire to be verbally savaged by the fanatical adherents of Brand C.  But I will let you into a secret: there aren't many companies out there making salmon lines for double handed rods.  A small group of manufacturers make lines for all sorts of brands, but are bound by confidentiality agreements to say nothing.  At the top end of the market the quality is uniformly high because the specifications and manufacturing processes are very similar, so there is little risk attached to your choice.

For simplicity let's consider Spey casting from first principles.  In the back cast the line forms the D loop.  The top part of the D loop comprises the mass, which when accelerated by the forward movement of the rod, creates the force that transfers to the rod as loading and bending.  The bottom part of the D loop, primarily the fly and leader, provides the anchor that prevents their acceleration and thus permits the formation of the forward loop.  At the stop in the forward cast, the energy stored in the bending of the rod is then transferred to the line, giving it the kinetic energy to carry the fly and leader payload to the salmon.  Line design is therefore a product of 3 factors:
  1. The 'back cast' space available for creating the D loop, bending force and subsequent energy transfer
  2. The mass and wind resistance of the payload
  3. And the distance required
This simple scaled picture shows an angler with a 14 foot rod with 3 different line types.

D Loop Sizes

The mass of all 3 lines is broadly similar: in this illustration I have used #9 rated 36gm/28' Skagit; a 34gm/38' Scandi; and a 37gm/55' Spey.  For simplicity I have excluded tips and leaders.  The Spey line is somewhat heavier owing to its more uniform weight distribution through nearly double the length, but presents the same loading to the rod.  The differing back cast spaces are clearly visible.

As an aside, I inserted the 2 coloured arrows to underline the essential physics of the Spey cast based on Newton's Laws.  As the rod tip accelerates forwards, the bottom half of the D loop is trying to move the other way, restrained by the anchor (which is why it flips out backwards and catches the grass if it's inadequate!).  The rod will continue to load and bend until the stop.  At this point applying further acceleration force is unnecessary, because the rod will do the rest of the job of converting its stored energy into the line's kinetic energy. Put simply, if a little paradoxically, it's the stop that makes it go.

Returning to the issue of line mass, this picture shows the relative thicknesses (and hence weights) of the 3 different lines.  The shadows create an illusion of additional thickness in the Skandi: in fact the Skagit has about 30% greater diameter.  Both are about double the dimension of the Spey.

The first point to note is that all 3 lines are profiled to have the majority of their mass embodied in the part of the head that forms the top portion of the D loop.  You don't need a lot of weight for the anchor, and the less mass you have on or near the water's surface the better.

The second is that the boundaries between the types are not clear cut.  For example, the Vision Ace Scandi shooting head has a short front taper and a profile quite close to the Skagit: as a result it is an excellent payload shifter at some compromise of presentation.  In comparison the Rio AFS shooting head has a long front taper (a bit like the Spey) that gives a lovely presentation of lighter flies and smaller tubes, but is less good at shifting heavy objects.  Its 2014 successor, the Rio Scandi, has greater weight shifting power at some compromise in presentation, although it remains markedly different to the Skagit.

In fact, ever since Rio introduced the first Windcutter to the UK in the late 1990s, most anglers have migrated towards designs that have shooting heads as their primary feature to some degree.  As a result, agreeing a definition of a 'Spey' line is becoming increasingly difficult.  Because this blog is not aimed at heroic casters, I have not considered the 'full' or 'power' spey lines with head lengths of 70' and more (and anyway, I've never used one since giving up on the inherited Aircel double taper in 2002).

The flow chart attempts to bring some simplicity to a very complicated area of decision making.  As a result it's necessarily rough and approximate.

I define heavy throw weight as big metal tubes, very fast sink tips and their combinations.  Light is normal doubles (up #6) with floating or intermediate tips; and medium everything else in between.

The flow chart emphasises the point that nothing shifts weight from a tight back-cast space like the Skagit. It isn't pretty and it can arrive with an awful crash, so don't use it in quiet or clear water.  But there are circumstances when nothing else will do.  It's the only fly line you can cast with smile on your face in a Force 6: it goes out like a javelin; and as a sustained anchor device it's very safe in tough conditions.  As a result I always have one in my pocket.

You will see that the Scandi is extremely versatile.  In the last 2 seasons it's become my line of first choice over the trusty Windcutter (which gave 10 years' excellent service until it died in an accident).  Once you get the hang of handling all the running line you can cast a good way with minimum effort and a light rod.  For many novices it's a good learning line with which to establish the basics. But it has some disadvantages: managing the running line is a skill of its own; and stripping it in can be a real time-consuming bore if you are fishing a wide flow at a consistent line length.

The next option is the weight forward 'short' Spey line with a head length in the range 45-50 feet.  It's a sound option, especially if you have a 15 foot rod.  It's very flexible and can perform all of the major cast choices.  It's less good for novices with shorter rods, for which the Scandi remains my recommendation.

Beyond that I won't state any brand preferences - they all have their loyal devotees - but at risk of boring you, do please buy the best you can afford.

Finally, two money saving tips:
  • Do not be seduced by the attractions of the very expensive multi-tip packaged lines.  I was in 2008 when I bought my new 14' rod, and I've regretted it ever since.  With experience I've found that a pocketful of Polyleaders and a couple of T11/14 tips is much cheaper and more flexible.
  • Don't invest in a sinking line or shooting head until you've mastered the floater.  By their nature sinking lines are harder work and demand very good technique.
In a future post I'll look at choosing a reel, but it will be short one.  As a small boy and fishing fanatic I was captivated by the beautiful engineering and craftsmanship in good reels.  I saved avidly to match my dreams until paternal wisdom intervened: "put your money into the line; if the reel goes round it'll do".  It's tough being a dreamer in a Yorkshire family, so I'll just put on my cap and pop out for the Hovis.

1 comment:

  1. I, like your grandfather, fish the smaller tree-lined rivers of the West Country (&Wales).

    I think he would have loved the new Scandi lines, especially the Rio Short Scandi Versitip on a single hander or short double hander, not to mention a Switch rod!

    This line has completely reformed my will cast anywhere, no matter how close or low the trees and has exceptional presentation. I fish places now where a few years ago spinning was the only option as a fly cast was nigh impossible!

    Great blogs Michael!