Annual Line Stretch Test (Updated 2016)

[Team9nine]

11 hours ago, fissure_man said:

 

Fair enough, good sir

 

Gaining insight into yielding behavior from a home experiment might especially be a “stretch”   Young’s modulus hinges on accurate line diameter measurements, and then kind of assumes that the diameter is constant throughout the sample – neither is likely very reliable.

 

BUT I’d think with a long-ish piece of line, it should at least be possible to get fairly precise measurements within the elastic range. It’d be nice, but it’s not necessary to have the whole curve.

 

The apparatus I’m picturing would be:

• 10-15 ft long stiff pipe (aluminum or steel), 1” diameter, held upright during test.
• Line is threaded through the pipe and attached to a cap on the top end, extending 6-18” out of the bottom end with a snap swivel to attach the basket. 
• A measuring tape/stick can be fixed to the bottom of the pipe, and the knot to the snap swivel is used as the measurement point.

With this setup, the initial length is fairly easily measured (pipe length + whatever sticks out at the bottom).  Running the line through the pipe prevents swinging, and holds the line close to the measuring tape for easy and accurate reading. 

 

In my mind, this setup could reasonably achieve 0.5 cm precision when measuring stretched length (<0.2% error for a 10 ft line).  If it takes greater precision than that to differentiate between lines, then that’s a conclusion in and of itself  

 

 

 

 

Kudos for doing the dirty work.  I hope my posts don't come off as critical, I like the tests and think it's spurred an interesting discussion.  Cheers

 

Yeah, I've done near 10' lengths off my garage door tracks with weights and a static ruler as well as 15' lengths along the floor with a force gauge and a taped in  place measuring device. Have also done 24 hour creep tests at 50% line rating. Used micrometer to measure all diameters to 4 decimals, plotted all points (stress vs strain) on a graph and compared multiple samples adjusting for diameter (tensile strength). All fun stuff. You get some nice graphs, but you can't pick out yield points from  the curves. Nylons tend to always stay in the elastic region (based on measuring permanent deformation after elongation testing and creep measurements) while fluorocarbon goes all over the map depending upon specific sample. It actually takes very little force in some cases to generate permanent deformation. Some low stretch  copolys do better than fluoros, and you end up with a mix of results. The real question to me seems more around our ability as anglers to actually be able to detect small differences in line elongation. Can you really tell the difference between a line with 16% "stretch" and a line with 13.5% "stretch" at a given force, or does knowing the data from your tests beforehand bias your perception otherwise? I'm personally not sold on "stretch" as a key metric for sensitivity unless taken to the extremes like comparing braids and super lines (2-6%) to monofilaments (20-35%+).

 

...and I too totally appreciate the tests like what FryDog did. I love the quest for data and answers, even if the ultimate outcome is somewhat limited or subjective. It's why I've spent so much time doing the same thing myself

[WRB]

Does anyone ever fish without using a rod?

Testing line for strecth is informative but worthless woithout also testing your rods lifting power becuase it's the rod and reel combo that applies pulling force onto the line.

What you will discover is the rod is the weak link, not the line. A 3 to 4 or MH power rod bottoms out around 3 to 4 lbs lifting or pulling force.  Dead lift test your rod-reel-line combo and you will discover line strecth occurs at a higher force than your rod can apply.

Tom

[fissure_man]

1 hour ago, WRB said:

Does anyone ever fish without using a rod?

Testing line for strecth is informative but worthless woithout also testing your rods lifting power becuase it's the rod and reel combo that applies pulling force onto the line.

What you will discover is the rod is the weak link, not the line. A 3 to 4 or MH power rod bottoms out around 3 to 4 lbs lifting or pulling force.  Dead lift test your rod-reel-line combo and you will discover line strecth occurs at a higher force than your rod can apply.

Tom

 

Not true.  

 

These tests by TackleTour used a 3 lb weight on lines ranging from 10-14 lb rated strength (0.30-0.32 mm diameter), and found results in the range of 10% elongation.  On a 50 ft cast, that’s 5 ft of stretch! 

 

http://www.tackletour.com/reviewfluorocarbon2.html

 

3 lb is still a lot, but do you think at 2 lb, 1 lb, 0.5 lb, the stretch would suddenly drop to zero?  Why?

 

[Montanaro]

Id like to see sunline shooter tested.  Its suppose to be the true low stretch fluoro

[WRB]

1 hour ago, fissure_man said:

 

Not true.  

 

These tests by TackleTour used a 3 lb weight on lines ranging from 10-14 lb rated strength (0.30-0.32 mm diameter), and found results in the range of 10% elongation.  On a 50 ft cast, that’s 5 ft of stretch! 

 

http://www.tackletour.com/reviewfluorocarbon2.html

 

3 lb is still a lot, but do you think at 2 lb, 1 lb, 0.5 lb, the stretch would suddenly drop to zero?  Why?

 

The TT stretch test used a constant 3 lb load, what they fail to disclose is the time factor or rate of applied force, very important with any plastic. For example a rate of load of 1second verse 1minute or 1 hour significantly changes the data. The strecth is linear however doesn't occur until the line reaches it's yield strength, if that is below 3 lbs the movement is minimal as indicated Sunline Shooter in this test.

By the way this test was FC, the line that has less strecth than mono proved that statement as being not true.

Try hanging a 3 pound weight on you rod tip held at 45 degree angle using the 10-14 mono or FC line and measure the line line stretch.

Tom

 

[Team9nine]

I think we're back to a semantics/definition hurdle  Dead weight lifting with typical rods is certainly to the low end  in most cases as Tom suggests, but elongation of line occurs at very low forces. Easy to test and prove to yourself, but this elongation is part of the elastic phase where the line returns to normal. If Tom is referring to "stretch" as exceeding the yield point of the line, moving into the plastic deformation phase of elongation, then he is likely correct, at least with most nylons that tend to be highly elastic. Testing has shown fluorocarbons to reach yield points with rather low levels of force. So I think we're discussing around a difference in definitions. The other point I'd mention is hook setting is often more of a shock force for lack of a better term, and again, testing has shown that at least at pitching distances, you can generate double the amount of force that a rod might struggle to deadweight. @Catt  has posted about testing stretch on the water with hook sets at distance and while it was minimal (<24") it still existed.

 

-T9

[WRB]

Just trying to keep the stretch test practical so we can understand what is happening while fishing. FC line is marketed as having low stretch and it does feel like it has less stretch then equal lb test mono line when fishing with it. Testing clearly shows mono and FC are nearly indenticle regarding actual % of stretch under equal loads...why?

What we feel as stretch is actually bow or slack in the line being tightened as we apply pressure. Nylon mono line has a higher coeffient of drag going through water, FC and braid has lower drag, cuts through the water with less force, creates less bow slack in the line. It doesn't take much force to reduce slack line, but we feel the movement as stretching. Add to the feel of line movement to your rod bending and it seems the mono line is elastic.

Very fast shock loading in milliseconds would be called impact strength in the plastic testing. Nylon has high impact strength, the reason it has excellent knot strength.

Tom

[Team9nine]

6 minutes ago, WRB said:

 

Very fast shock loading in milliseconds would be called impact strength in the plastic testing. Nylon has high impact strength, the reason it has excellent knot strength.

Tom

 

No qualms here with that explanation, but would you then agree that one of the reasons for nylons high impact strength is it's high degree of elasticity (elongation/stretch) which acts as a shock absorber?

[WRB]

To some degree your rod is a good shock absorber. Impact is usually tested by dropping a specific weight round steel ball from a controlled height and the deformation recorded.

Some very high impact Nylons are reinforced with glass fibers that lower the elongation %.

In terms of the TT test, if the 3 lb weight was dropped 1 foot with slack line all the lines tested would break if tied to an infinite mass and more than likely pass if tied to your rod.

Tom

 

[fissure_man]

59 minutes ago, WRB said:

The TT stretch test used a constant 3 lb load, what they fail to disclose is the time factor or rate of applied force, very important with any plastic. For example a rate of load of 1second verse 1minute or 1 hour significantly changes the data. The strecth is linear however doesn't occur until the line reaches it's yield strength, if that is below 3 lbs the movement is minimal as indicated Sunline Shooter in this test.

By the way this test was FC, the line that has less strecth than mono proved that statement as being not true.

Try hanging a 3 pound weight on you rod tip held at 45 degree angle using the 10-14 mono or FC line and measure the line line stretch.

Tom

 

 

The loading rate would be important in extremes, but I imagine it was relatively quick.  Why would TT bother gradually loading over an hour?  Or running a dynamic ‘impact’ test without mentioning it in the review? 

 

If significant plastic creep was induced, then the % rebound would be reduced.  Most FC’s did show some non-reversible deformation, but Shooter didn’t, and the control mono (Trilene XL) didn’t either (they still stretched, though).  This shows that the measured strains for at least those two samples were fully elastic; the others were “mostly elastic.”  For a static test, where behaviour is elastic, results shouldn’t be sensitive to loading rate at all, right?

 

6.3% stretch for Sunline Shooter is better than the others, but hardly “minimal.”  That’s 2.5 ft on a 40 ft line.

 

40 minutes ago, WRB said:

Just trying to keep the stretch test practical so we can understand what is happening while fishing. FC line is marketed as having low stretch and it does feel like it has less stretch then equal lb test mono line when fishing with it. Testing clearly shows mono and FC are nearly indenticle regarding actual % of stretch under equal loads...why?

What we feel as stretch is actually bow or slack in the line being tightened as we apply pressure. Nylon mono line has a higher coeffient of drag going through water, FC and braid has lower drag, cuts through the water with less force, creates less bow slack in the line. It doesn't take much force to reduce slack line, but we feel the movement as stretching. Add to the feel of line movement to your rod bending and it seems the mono line is elastic.

Very fast shock loading in milliseconds would be called impact strength in the plastic testing. Nylon has high impact strength, the reason it has excellent knot strength.

Tom

 

Sure, drag in the water is real, and affects how a line “feels” in use.  But that’s in addition to stretch.  Anyone who’s fished on a short line in shallow water with mono vs. braid can still feel the difference in stretch.  In 2 ft of water it’s not a result of water resistance.  Looking at it another way: in typical bass fishing conditions, what will feel more "stretchy," 4 lb mono, or 50 lb braid?  The mono should have less drag in the water, right?

[WRB]

When testing materials the rate of load is controlled by a standard method and test procedure, TT made up thier own test methods and procedures.

 A load rate of .25 inch/second is common to determine elongation, no idea what TT did?

Creep would increase the elongation %; time over force. Example; hang the 3 lb weight over a 24 hour period at ambient temps, the stretch numbers would be higher.

coeffient of drag has to do with the material not just diameter, more surface area increases drag for all materials.

To "feel" line drag going through water simply run 30 yards behind a moving boat without anything tied on the end about 5 mph, make slow turn and straightened out. Notice the line follows the boat wake. With 6 to 8 lb test mono the force applied to increases as you turn, decreases as you run straight; about 1 lb of drag. Repeat the same test using FC line equal dia and the drag drops about 50% and the line tries to run straight to one side of the wake.

I do this nearly every day when untwisting my spinning out line and was one of the first indications how mono and FC differ.

Tom

[Team9nine]

44 minutes ago, WRB said:

To some degree your rod is a good shock absorber. Impact is usually tested by dropping a specific weight round steel ball from a controlled height and the deformation recorded.

Some very high impact Nylons are reinforced with glass fibers that lower the elongation %.

In terms of the TT test, if the 3 lb weight was dropped 1 foot with slack line all the lines tested would break if tied to an infinite mass and more than likely pass if tied to your rod.

Tom

 

 

And therein lies part of the problem of teasing out an answer under real world applications. Since we don't fish with broomsticks, the rod will certainly accept a portion of the shock, and hence reduce overall elongation of the line. This is where the TT test fails to go (and it probably wasn't meant to go there). However, it also seems a bit naive to assume the rod will absorb 100% of the shock, and that some portion will ultimately be absorbed by the elasticity of the nylon. 

 

28 minutes ago, fissure_man said:

 

Sure, drag in the water is real, and affects how a line “feels” in use.  But that’s in addition to stretch.  Anyone who’s fished on a short line in shallow water with mono vs. braid can still feel the difference in stretch.  In 2 ft of water it’s not a result of water resistance.  Looking at it another way: in typical bass fishing conditions, what will feel more "stretchy," 4 lb mono, or 50 lb braid?  The mono should have less drag in the water, right?

 

Similar to my above comment, the answer is probably variable and dependent upon length of cast. In short scenarios such as you mention, drag and slope would hardly come into play, and it would all be rod flex and line elongation. However, on a 90' cast into 18' of water with a worm or jig, those variables Tom mentions should have a much more important role in the equation.

 

It all makes for fascinating discussion in my book 

 

Thanks @fissure_man @WRB !

[fissure_man]

41 minutes ago, WRB said:

When testing materials the rate of load is controlled by a standard method and test procedure, TT made up thier own test methods and procedures.

 A load rate of .25 inch/second is common to determine elongation, no idea what TT did?

 

Yes, but my point is that in this case, using proper procedures wouldn’t change the results so significantly that the conclusions would change.  Or at least “the conclusions as they apply to this discussion” wouldn’t change.  Stretch occurs in these materials, and it begins at very low force (well within the range that is reasonably applied while fishing).

 

42 minutes ago, WRB said:

To "feel" line drag going through water simply run 30 yards behind a moving boat without anything tied on the end about 5 mph, make slow turn and straightened out. Notice the line follows the boat wake. With 6 to 8 lb test mono the force applied to increases as you turn, decreases as you run straight; about 1 lb of drag. Repeat the same test using FC line equal dia and the drag drops about 50% and the line tries to run straight to one side of the wake.

I do this nearly every day when untwisting my spinning out line and was one of the first indications how mono and FC differ.

Tom

 

This is very interesting.  What’s the cause, if the diameters are the same?  Chemical characteristics of the different materials, ie: how they interact with water on a molecular level?  Texturally I imagine they’re the same on a macro-scale…  Do they drag at different depths, surface vs underwater?  Could a difference in stiffness cause a flutter effect, turbulence around the line?  Just spit-ballin   50% is a dramatic difference

 

I do the same thing, but all my spinning reels are loaded with braid.

 

42 minutes ago, Team9nine said:

 

And therein lies part of the problem of teasing out an answer under real world applications. Since we don't fish with broomsticks, the rod will certainly accept a portion of the shock, and hence reduce overall elongation of the line. This is where the TT test fails to go (and it probably wasn't meant to go there). However, it also seems a bit naive to assume the rod will absorb 100% of the shock, and that some portion will ultimately be absorbed by the elasticity of the nylon. 

 

 

Similar to my above comment, the answer is probably variable and dependent upon length of cast. In short scenarios such as you mention, drag and slope would hardly come into play, and it would all be rod flex and line elongation. However, on a 90' cast into 18' of water with a worm or jig, those variables Tom mentions should have a much more important role in the equation.

 

It all makes for fascinating discussion in my book 

 

Thanks @fissure_man @WRB !

 

Agreed.  It all still passes the ‘gut test’ I think.  On a sharp hook set with a soft rod, the rod bends dramatically, absorbing your energy input and limiting the peak force you can generate, resulting in minimal line stretch.  With a stiff rod and the same hook set, something’s gotta give.  The rod doesn’t ‘give’ as much, leading to greater force applied to the line for the same ‘swing arc,’ and more line stretch.  With either rod, a static test (dead weight or a steady-pulling fish) would result in the same amount of line stretch, because the force on the line is the same.

[MIbassyaker]

This thread deserves a sticky.

[WRB]

The bubba hard hook set moves the hook very little at 30+ yards unless you first recover slack line. Years ago I demonstrated this at a seminar by holding a jig between my finger tips and let a bass angler perform his best hook set...the jig didn't pull out of my finger tips.

When you reel up the slack line quickly, the rod sweep into snag line you can't hold onto the jig, in fact you better be careful because that jig moving Fast.

Setting into controlled slack line using a snap set when the line is about 30' away will also drive the hook point home.

I use 10lb to 12 lb mono and FC jig and worm fishing for decades and get good hook sets at over 40 yards, my rod are 6'10" heavy 5 & 6 power fast action bait casting rods. I am talking about DD size big bass hooked through the upper jaw with jigs! I use the eel and rod sweep hook set very effectively. Line stretch is way over thought by bass anglers.

See my 19.3 lb avatar bass, caught in 18 feet of water over 100 feet away from the boat when it bite, 12 lb Big Game mono line on a jig with 5/0 hook!

Tom

[fissure_man]

12 hours ago, WRB said:

The bubba hard hook set moves the hook very little at 30+ yards unless you first recover slack line. Years ago I demonstrated this at a seminar by holding a jig between my finger tips and let a bass angler perform his best hook set...the jig didn't pull out of my finger tips.

When you reel up the slack line quickly, the rod sweep into snag line you can't hold onto the jig, in fact you better be careful because that jig moving Fast.

Setting into controlled slack line using a snap set when the line is about 30' away will also drive the hook point home.

I use 10lb to 12 lb mono and FC jig and worm fishing for decades and get good hook sets at over 40 yards, my rod are 6'10" heavy 5 & 6 power fast action bait casting rods. I am talking about DD size big bass hooked through the upper jaw with jigs! I use the eel and rod sweep hook set very effectively. Line stretch is way over thought by bass anglers.

See my 19.3 lb avatar bass, caught in 18 feet of water over 100 feet away from the boat when it bite, 12 lb Big Game mono line on a jig with 5/0 hook!

Tom

 

One could say you’ve “mastered” the skill of managing slack during hooksets (and overcoming stretch). 

 

For those less practised, who occasionally still whiff on a hookset, wouldn’t less stretch sometimes be an advantage?  If someone neglects to fully reel up the slack before setting the hook, having a stretchy line makes it even less likely they’ll achieve a firm hook set.  On a long distance hookset like you describe there is certainly line stretch involved that reduces the force delivered at the hook, even if you are adept at overcoming it.

 

I assume your preference for 5-6 power fast action rods is because they are relatively 'stiff.'  As discussed above, the effect of rod stiffness is very similar to the effect of line stretch.  Your hook-setting efficiency would be compromised by too soft a rod, just as it would be by a line that's too stretchy.  Within reason, the impact of either scenario could be offset with good technique, but why not stack the odds in your favor?  Or at least factor it into the pros/cons list when choosing a line type. 

 

It’s not just hook setting, stretch can affect how lures work too – jerkbaits on long casts, ripping through weeds, walking the dog.  Any technique can be done on any line, but the feel changes, and people will have preferences.  As T9 pointed out, minor variation in stretch between different monofilaments is probably insignificant, but the jump to braid is noticeable IMO, whether good or bad.

 

Everything on this site is over-analysed, why not stretch?  It’s no worse than debating 6’10” vs 7’ rods, or preferring 24.19432 IPT for deep cranks

 

--------------------

Other random points:

 

Do you think the density of flouro lines tends to reduce the amount of slack line in play for baits like jigs/worms by giving a straighter connection to the lure (less bow), which also contributes to the apparently increased sensitivity?

 

As in my last post, any thoughts on ‘why’ fluoro would have less drag in the water vs. mono of the same diameter in your boat-dragging example?

[WRB]

Every bass angler needs to develop and master hook setting techniques if they want to advance in catching bass with all types of lures. The rod plays a critical roll in casting lures, retreiving lures and controlling bass after the hook set. I will say this one more time "mono line stretch"  is exaggerated in the minds of most bass anglers due to marketing of FC line.

Braid stretches less is true, mono and FC as leaders used for shock absorbing is a another myth, line breaks before the line can strecth enough to prevent knot failure, the rod is your primary shock absorber coupled with reel drag slipping.

Tom

[TX-Deluxe]

On 3/23/2016 at 6:00 PM, Team9nine said:

That experiment has been done. Since you are barely generating over a pound of hook-setting force at that distance, and taking into consideration the bend of the rod, the mass of the fish, your stated depth of water and the drag effect on your line in water (and the non straight-line nature of the line in these circumstances), I believe the answer to actual line stretch is very likely less than 2' at that distance.

-T9

So if you use a 7" rod over a 6' would that take up 1' of the stretch on the hookset?

[Maxximus Redneckus]

Still before a hookset rod ,drag ,then when the hook does make contact the rod the drag then the line comes into play...normally unless you have a locked down drag and a xxxh rod the line will   come into play before the reel and rod

[Team9nine]

11 hours ago, TX-Deluxe said:

So if you use a 7" rod over a 6' would that take up 1' of the stretch on the hookset?

 

It would take up more than 1' since the rod tip moves in an arc and not a straight line, but it wouldn't necessarily come from the stretch. In fact, ironically, it's possible the stretch could be worse (marginally) because you might actually apply more pressure to the hook. (via the line), though even there some (older) studies have shown no difference in hook setting force based on rod length. There are a lot of variables in play making it hard to make any absolute statements.

[Ski]

 

 

I realize in the last 5 years there have been advancements in lines however I found this interesting.