It's a slow time of year here at camp, which leads to a lot of excessive thought lol I have spent more time online viewing line test videos and reading line test results, etc... than I care to admit. Something that has always caught my interest...

Has anyone ever conducted tests that measured the sink rate and stretch of mono lines after 30 minutes in water, 2 hours, 4 hours, etc?

It seems like most tests, if not all conducted that took into account saturation, left the mono in water for a full day, which isn't realistic for actual fishing conditions as obviously your line isn't always submerged. Each time the line is removed from the water and casts, does it shed enough to stop it from soaking up water? Once a line has soaked up water, how hard is it to get rid of it, does it ever "dry out"?

My thought process is that, if mono is soaking in water, that would impact sink rate, but the longer I have ever fished throughout a day using the same rod and mono line, it sure doesn't seem like it changes. So, throughout the course of a day of fishing, is mono actually soaking up much water and to what degree?

If in actual real World fishing conditions, mono doesn't soak up much water, if any, then these tests portraying the fact that as mono soaks up water, it stretches more would not be actually occurring throughout the day while fishing. Obviously if this is true, then without a doubt many copolymers or monofilaments in real World circumstances, stretch less than most fluorocarbon lines by quite a bit.

Really really wish I had access to a real lab with the proper stuff to test this, with fluoro and braid coming on the scene so much the last 20 years, mono really took a back seat in so many ways, but have been fishing it more and more with moving baits and really digging it the past year.

Any scientists on here with some logic that would bring any clarity to this?

I have several lines here that are all claimed to be the same diameter, of .010" (10 pound Sunline Super Natural, 10 pound Seaguar Tatsu, 10 pound Sunline FC Sniper)

I was thinking of attempting to test this once it warms up a bit this Spring and adding a couple more mono/copolys to the mix, like McCoys and Gamma, just because I have never tried them and would like to. Would be interesting to see.

If Yo-Zuri could just squeeze a tiny bit more limpness out of their 6 pound .010" line, would probably be the ultimate, but I just do not love that stuff on my spinning reels.

6 hours ago, Peninsular said:

Has anyone ever conducted tests that measured the sink rate and stretch of mono lines after 30 minutes in water, 2 hours, 4 hours, etc?

I'll take a stab - I've done a lot of testing and researching of the various line types...

It seems like most tests, if not all conducted that took into account saturation, left the mono in water for a full day, which isn't realistic for actual fishing conditions as obviously your line isn't always submerged. Each time the line is removed from the water and casts, does it shed enough to stop it from soaking up water? Once a line has soaked up water, how hard is it to get rid of it, does it ever "dry out"?

'Dry' mono absorbs water rather quickly, as much as 8-10% by weight. A test should probably use 2 hrs as a baseline soaking time before testing, as the majority of total absorption occurs within that time frame. 'Casting' would only shed excess water off the surface, but probably doesn't affect internally absorbed water. Once you stop fishing and store your gear, water evaporates back out of the line, especially in dry conditions or in sunlight, but it takes some time, which varies by conditions.

My thought process is that, if mono is soaking in water, that would impact sink rate, but the longer I have ever fished throughout a day using the same rod and mono line, it sure doesn't seem like it changes. So, throughout the course of a day of fishing, is mono actually soaking up much water and to what degree?

Mono (Nylon), put into water (set or casting), absorbs most of its water in the first 90-120 minutes. It's a fairly quick process as you've probably observed noticeable improvement in handling and casting when first starting a day of fishing, usually within the first 15-30 minutes of use. Differences in sink rate would likely be unnoticeable as the density of nylon is already slightly heavier than water, and soaking up more water should just bring it closer to the density of water itself, so closer to neutral buoyancy.

If in actual real World fishing conditions, mono doesn't soak up much water, if any, then these tests portraying the fact that as mono soaks up water, it stretches more would not be actually occurring throughout the day while fishing. Obviously if this is true, then without a doubt many copolymers or monofilaments in real World circumstances, stretch less than most fluorocarbon lines by quite a bit.

The characteristics of the line change quickly as the water is absorbed, and those include an increase in 'stretch', and a decrease in tensile strength and abrasion resistance, as much as 10-15%. Pure fluorocarbon doesn't absorb water, so as mono (nylon) does, in 'real world' circumstances, mono would end up stretching as much or more than fluoro due to this.

I never thought of cutting a shorter section and weighing it on a scale, that would tell you a lot.

Interesting stuff, seems like you have done your homework, I enjoyed you and the guy named Tom's posts here on the site "may he rest in peace" going through the archives, there is more seemingly "good" info on lines of this nature in the archives of this site than likely anywhere else.

Will be interesting to see if in the coming years with AI advancements if there is really any breakthroughs in line tech, most of the best lines on the market, mono, braid or fluoro have been around for many years.

I never found any of the YouTube tests to be very applicable for my needs, there is one test in particular on YouTube that claimed a certain fluorocarbon line to be the best in that test, so I bought a spool last year, Spro Gouken, holy moly, if you thought Invizx was a stretchy line, that Gouken stuff is like fishing with a banjo string, you can literally hear it stretching, just working a skirted jig and trailer you could feel the stretch lol Was awful... Couldn't get Shooter back on my reel fast enough.