[Irvine Ross]

OK, I'm taking this to extremes, so shoot me down when you spot the flaws.

If you had a long enough length of a very elastic line, and assuming you could make the back cast somehow, it is possible you could complete the full forward cast and only have partly stretched the line so that the point of the line would not have started moving forward at all.

Once you had completed the forward cast, the tension on the line would be released but the biggest mass of the line would be behind you. At this juncture the elastic would contract and the main mass of the line would pull the loop backwards.

Therefore if you want to transfer the acceleration of the rod tip to the main mass of the line, which is 30' -60' behind you, you are better off with little or no stretch in the line.

So much for the theory. Bring on the tablets of stone Magnus  

Irvine

[Mike Barrio]

Lots of great replies folks

Best wishes
Mike

[Magnus Angus]

Yes silk is a non-stretch material.

There's no evidence that we can load and unload the line. Thing about a fly line its a very distributed weight - unlike a weight on the end of a braid. The maths is frightening but essentially I agree with Rob about the response to a low load and the damping effect of water.

When casting, despite what it feels like at the grip, we apply a relatively small force on the line - that force grows larger in the early part of the stoke but is still not frightfully big at it's maximum - it peaks just just after the moment when the rod is at maximum bend and is ridiculously small in the moments before the line overtakes the rod tip and forms the loop - when the force on the line falls to zero. The period from maximum bend to the rod coming straight is what casters call 'the stop', it's during that time as the rod straightens that we may benefit from a small amount of energy stored in the rod as Spring PE - the vast majority of the energy in the moving line comes from leverage applied directly to the line by the rod. (I suspect is you stretch a fly line and let it go the time it takes to 'recover' would mean it has no effect in casting - but the real point would be that when we cast there is no large weight on the fly end. The tension in the fly line is highest near the rod tip and drops to near zero at the fly end of the line when we're casting.)

Tournament casters are the guys who have really worked on this subject because they use some extremely heavy, relatively short shooting heads, so if any fly casters should see a difference they should - and they don't.

However - what we do know is fly lines are made of a strong core with a coating wrapped around. The coating provides the density (floating sinking etc) the core provides tensile strength. The core and coating are radically different materials so the composite can cause problems. For instance, if a coating is less elastic than the core and or is very difficult to bond to the coating then the core will in the worst cases break off in chunks in most it will eventually start to crack. Unsurprisingly, the company who started to make a fuss about fly line core and stretch use a coating which while great in some ways did not stick to the core very well - so they had problems with conventional core materials which have a certain amount of give.

On feeling takes - imho we usually see a take long before we feel anything. So called smash-takes are in my opinion evidence that we are tightening into a fish which has taken the fly has hooked itself and is already moving at speed before we feel anything - and they 'smash' because we either don't respond quickly enough or because the rod is pointing down the line we apply the greatest possible tug on the line. If the same happens when the rod is at an angle - no smash! That's why top class river anglers fish deep nymphs with a slightly raised rod and a curve in the line.

[Iain Goolager]

That's why top class river anglers fish deep nymphs with a slightly raised rod and a curve in the line.

Even some 'lower class' river anglers do this Magnus 

[Rob Brownfield]

Even some 'lower class' river anglers do this Magnus 

And even some "scum" class do to! ..but not often enough! 

[Mike Cleaves]

I have been using various non-stretch fly lines for the last 6 years on lakes and rivers. I have experimented by comparing standard stretchy fly lines with my homemade non-stretch fly lines and feel that I catch more fish with the non-stretch lines, whether it be full sinking, sink tip, or floating. Playing a fish with a non-stretch line on a lake seems to me that there is more feedback as to the direction the fish takes and the ability to turn sea trout on rivers when it heads back downstream is an advantage when the angler cannot follow due to obstacles. My homemade lines have absolutely no memory, a big advantage when fishing a 'static' dry fly or emerger on a lake when the surface drift is towards the angler. My lines are constructed from various UHMWPE floating braids with different diameters and lengths of sinking dacron.  In my opinion, take detection is much improved when fishing with a sink tip or sinking fly line. Proper scientific testing to validate my subjective experience can be really difficult to achieve, and probably impossible, but trends could be noticed leading to a fairly accurate conclusion.

[Mike Barrio]

Hi Mike - welcome to the forum 

Wow, that's an old topic to resurrect 

My thoughts remain much the same - and these things are probably mostly about personal confidence.

The point that Magnus made about the core and coating combination is the key.

Cheers
Mike

[Mike Cleaves]

My lines have no coating hence no memory or coiling. They absorb a certain amount of water which makes it harder to calculate the correct wet AFTM. This topic might be an old thread, however, I am only now seeing it. My lines would be difficult to mass-produce efficiently but they give me pleasure to use.  All the best!

[Mike Barrio]

Great stuff Mike, anything that gives you enjoyment is good, that's what fishing is all about 

It's also the beauty of a forum when compared with social media, you can actually find a 12 year old topic 

What are you doing with the braid, are you furling it? Sounds like fun.

Cheers
Mike

[Mike Cleaves]

As an example, the sink tip is constructed as follows. starting at the tip I have 3' of 1mm dia red & white dacron which is spliced to 8' of 1.3mm dacron which is spliced to 20' of floating red UHMWPE [Dyneema] which is then spliced to 0.8mm floating red dyneema running/shooting line. This is my 'go-to' line for nymphing on lakes. The wet weight of the head is 13.6gms which equates to an AFTM8. The free sinking rate of the dacron was approximately 6 seconds per foot before attachment to the floating belly. The tip is blobbed with a lighter flame to which is attached  20lbs bs clear mono with a 4 turn uni knot and looped to accommodate the leader. The only disadvantage of this setup is during the winter when my fingers get cold handling the wet line.

[Mike Barrio]

Looks like fun Mike - hope you enjoy a good season 

[Mike Cleaves]

Tight lines!   

[Mike Cleaves]

Interesting topic 

I can see advantages of low/non stretch in sinking lines (in particular) and whilst I suspect that a low/non stretch line could have an advantage for casting it would be minimal at best. A very small percentage in improvement with no real clear advantage over 'conventional' technology lines.
I suppose the only fair test would be to make up two fly lines of exactly the same profile and exactly the same weight cast them on the same rod and see which went further..... but even then the chances are that the next person to pick up the rod and cast both lines after each other might get a different result...... hmmmmm.
Lets' face it, if there were a huge advantage for distance then everyone but everyone going for distance competition casting would use one now wouldn't they As far as I'm aware they don't.
Do we look for low-stretch in sinking lines Well, I do as it happens. Trouble is I have a strong distaste for most products from a certain brand well known for being at the forefront of this 'technology', I tend to see most of their advertising material as quality bullshit of the highest order.
I remain to be convinced.

Hamish       

I prefer non-stretch fly lines which I construct myself. An example of one of my lines is :-  A sink tip is constructed as follows. starting at the tip I have 3' of 1mm dia red & white dacron which is spliced to 8' of 1.3mm dacron which is spliced to 20' of floating red UHMWPE [Dyneema] which is then spliced to 0.8mm floating red Dyneema running/shooting line. This is my 'go-to' line for nymphing on lakes. The wet weight of the head is 13.6gms which equates to an AFTM8. The free sinking rate of the dacron was approximately 6 seconds per foot before attachment to the floating belly. The tip is blobbed with a lighter flame to which is attached  20lbs bs clear mono with a 4-turn uni knot and looped to accommodate the leader. The only disadvantage of this setup is during the winter when my fingers get cold handling the wet line. Full sinkers are made from dacron at different diameters. Lines are spliced together in different combinations. I have had sea trout smash my 12lb leader when using a stretchy line, this has not happened to me using a non-stretch line with the same B.S.  nylon leader. If a sea trout gets up a head of steam swimming downstream after taking a fly and the take is not detected early enough then I can see why it is possible for a break to occur. With a non-stretch fly line I find that I can set the hook earlier before the fish can accelerate downstream which lessens the load on the leader. My lines have no memory as there is no coating to contend with. The dry weight is lighter than a standard AFTM number, but the lines will absorb some water thus increasing the weight for casting.