"
A few questions.
1. What knot did you use?
2. Why test stretch at line strength without using 75%* of line strength? 8 lb @ 6 lb load?
3. Did you measure the line? What with?
* it's impossible to apply 8 lbs load with tackle used to fish 8 lb line, 6 lbs is high enough to yield 8 lb line.
The lines should be grouped by diameter, 8 lbs label line with .009-.0095 only. Any line larger diamter like Yo-Zuri @ .011-.0115 should be at 12 lb test or 75% = 9 lb load.....apples. To apples. Yo-Zuri 4 lb test is .009, use that in your 8 lb category for example. Sunline and others 12 lb line is .011-.0115, use those to compare line in the .011 diamter class.
Your stretch test shows how honest line mfr's are, good post!
Tom "
Tom, I'll try to answer most of your questions best I can:
1) I used a double Palomar knot. Where lines broke, it was up the line above the weight...the knots held.
2) I think there are a number of ways to do this test and I may do more. The reason I picked an 8 pound weight was to use the maximum so as to accentuate the difference between the various lines. Although a lesser weight might be closer to the real world, some of the results might be closer together and harder to see differences. We're all looking for subtle differences in the products we choose, and I wanted to try to make those differences as obvious as possible. If I get time, I may do another round of tests at 4 pounds on a cross section of these lines.
3) I measured the lines with - what else would a fisherman use - a Hawg trough... Ha! Of course I'm Kidding, I used a tape measured and tried to get down to 1/8 inch.
4) Yes, I do think that line diameter can make a difference in stretch - that's why I did the second breakout with just those that were .009 inches in diameter and throw out the Yo-Zuri's and XT's that were thicker. There were 9 lines (half of the lines tested) that fit the .009 criteria. But in terms of the 3 different line categories, fluorocarbon still stretched the most. P-line CX co-polymer and several of the fluorocarbons were the same diameter but CX stretched less - and maybe most importantly, didn't break.