Deciphering Braid Ratings: Diameter, Test , and PE Number

[jurelometer]

[Updated 12/4/23: corrected a couple mistakes: I left a zero off on the denier formula. I fixed the related math as well. Also downgraded the PE number usefulness, as the PE standard allows for a huge range]


Every time I read about braid diameter or breaking strength, I cringe a little,  knowing that these numbers are kind of made up.  I knew that PE rating was based on weight to length, but not the actual ratio. I did some research on what PE actually means, and thought to provide a primer on how to decipher what is printed on the side of a braided line spool.  Hope that y'all might find this useful.

-----

First of all, there are three numbers that we may see on a spool of braided PE (AKA Spectra/Dyneema) fishing line to identify the size.  Two of the three are mostly marketing junk, and the third has too large a margin of error.

  Diameter (junk)   In order for an object to have a diameter, it has to be round and solid enough to be objectively measured.  Braid is just a loose weave of fibers, so it has no diameter.  The line companies  simply "estimate" diameter.  An ethical estimate would be the "equivalent"  monofilament diameter (same number of yards to fill the same spool).  Diameter is easily measured for mono if you have some calipers. Anybody that tries to measure braid diameter is just fooling themselves.

Breaking Strength/Test (junk) or IGFA rating (semi-junk) .  This is the breaking strength of the line.  But not really.  For marketing reasons ("We have the strongest 20 lb test", or "We have the thinnest 20 lb test") the actual breaking strength can be anywhere from a bit below to much higher than the listed rating.

And to make things more confusing, we  have the inverse:  Lines that are made for tournament fishing will list an IGFA rating which "guarantees"  that the line is no stronger than the test number, but might be much weaker.

In general, fishing line strength rating for the US consumer market will be much greater (often 20% or more) than the IGFA rating, while lines headed for the Japanese consumer market will tend to list an estimate close to the IGFA number.

What would actually be useful but  is not provided is an accurate minimum to maximum breaking strength range using a standardized process. But not much of a chance of that happening


PE Number (semi-useful)   This is simply a number that corresponds to the denier of the line.  Denier is a weight to length measurement used in the textile industry for all types of woven fibers (yarns), and is calculated in grams per 9000 meters (just under 10,000 yards).

The JAFTMA (Japan Fishing Tackle Manufacturers Association) JAFS-D10111002  standard defines one PE as 200 denier.  In other words, 9000 meters of "PE 1"  line would weigh 200 grams, "PE 2" line would be 400 grams per 9000 meters, and so on. While it appears that most manufacturers stick reasonably close to the target denier, (according to google translate) the standard allows for a pretty huge range (basically no more or less than the adjacent PE sizes):
https://www.jaftma.or.jp/standard/pdf/pe.pdf


So how is this useful?  First two lines with the same PE rating will be about the same effective thickness when you are pulling them through the water. Second, it is the cumulative mass of the braid that determines how much line will fit on your spool.  If your spool can hold 10 grams of PE fibers it will hold 450 meters of PE 1 or 225 meters of PE 2 braid, and the difference between brands should be minimal.

Easy peasy.  So it is not hard to figure out to compare sizes and capacities of different braids if the PE  numbers are available, but we have to take any strength rating as sort of a ballpark number, and not mix up the US vs. Japanese market ballparks.  Not sure what happens in Europe. Pacific, etc...

-J 

[Update]  I had to shovel my way past a pile of internet "efluencer" fertilizer to find the above information, but just found a nice single source reference here from a reputable manufacturer:
https://www.varivas.fishing/japanese-fishing-line-size/


Varivas makes some good but expensive fishing products, mostly for the Japanese markets.  They make my favorite saltwater fly hooks for my go-to patterns.  They have some lines for the BFS crowd too.  Worth checking them out.

-J

[jurelometer]

A bit more on the Japanese standards - You may have the terms  "gou" or "gouw".  This is just the phonetic  spelling of the Japanese 号, which means "number" (as best as I can tell). 

The JAFTMA PE number is the "gou" for braided line.  There is also a JAFTMA standard number for monofilament lines which is based on actual diameter, since monofilament has a measurable diameter.   You can find   tables for both at the Varivas link referenced in my original post.

-J

[boon]

Unfortunately the specification that is usually sought after is the breaking strain of the line, which is bordering on pointless to try to estimate from any of the above, even the manufacturers stated breaking strain.

I try to find the thinnest line that will still satisfy the strength requirement. But working out in practical terms what that actually means tends to require field testing, which can be an expensive failure if you go too light. I tend to just go thinner and thinner until I start encountering breakages. With Ocea 8 braid I got to the point of "this braid is too thin" before I hit "this braid is too weak".

[Swami805]

That makes sense, thanks. Still a bit hard to wrap my head around when going by breaking strength for a lifetime. Be helpful if American companies would star using it

A bit more on the Japanese standards - You may have the terms  "gou" or "gouw".  This is just the phonetic  spelling of the Japanese 号, which means "number" (as best as I can tell). 

The JAFTMA PE number is the "gou" for braided line.  There is also a JAFTMA standard number for monofilament lines which is based on actual diameter, since monofilament has a measurable diameter.   You can find   tables for both at the Varivas link referenced in my original post.

-J

[Keta]

Most Spectra breaks well above the rating and with the exception of specialized uses,  like deep slow pitch, I ignore the ratings.  Most of my 30 to 60 pound reels have 60/65 pound, my 80-100 pound reels have 100 pound.  My heavy reels have 130 and 200 pound, 130 on top of 200.  I have a few tiny reels I use 30# on.

For deep slow pitch I go by the manufactures PE rating and what the rod was built for.

I set up a reel for BFT jigging at night with 65#, it consitantly breaks at slightly under 80#, for when the drift is bad. The drag is set at 24# at strike.  So far I have not had the opportunity to test it, but hopefuly I will in mid May 2024.

[Cor]

Nice explanation of mostly marketing information.
Thanks.
 

[Robert Janssen]

Yeah... I just got back from Japan, and had to figure this out on the spot.

As it happens, one of the things I bought just happens to be Veritas leader line, quite clearly marked as 80 gou and diameter 1.48 mm.
When I got home and measured it, it turned out to have a diameter of 1.57mm, which as we now know is more like 90 gou.
The line itself is very nice and looks and feels like high quality stuff.
So I can only imagine that human error was responsible... that whoever was at the factory that day drew 50 meters off a bulk spool and accidentally popped it into the wrong bag.
( I don't mind at all. A bit of extra strength is totally okay. Great price too. )
I also bought 50m of 80 gou fluorocarbon, which was quite accurately 1.48mm in diameter.

Braided line is of course harder to measure. But, in the case of hollow core, its thickness can be measured by inserting something of known diameter and measuring that. In this case, a 1.2mm monofilament in the hollow core gives an OD of 1.6mm. Thusly, it can be deduced that the hollow core has a wall thickness of 0.2mm. However, that says nothing at all about the quality or density of braiding or anything else, really.
This happens to be 200lb Diamond Braid, labeled as 0.80mm diameter.

[jurelometer]

When trying to figure out how much a spool fill adds to the weight of the reel, I realized that I must have made a math mistake (shocking, I know ).  I left out a zero on the denier formula, which of course equates to an order of magnitude.  Doesn't really change the point of the post, but I did update it, so that it will be correct.

I also got another nagging thought:  I didn't see the range of denier that was allowable for the PE standard anywhere.  Better look that up, too: 

I ran the standard (https://www.jaftma.or.jp/standard/pdf/pe.pdf) through Google translate and got this for range:

4 The allowable range of PE yarn is that the denier at the upper and lower limits does not overtake the standard value of the front and rear patterns. Shall be. /i]

The PE standard lists a discrete set of PE sizes, so I interpret the above to say that the denier of a product labeled at a given PE size has to be between the denier of the size above and the size below.  A pretty huge range!

I have only done a few fills of spools based on PE size, but from what I have seen on the interwebs so far, the Japanese manufacturers tend to keep close enough to the target denier to make the PE number useful (same as they do for breaking strength). Checking PE accuracy is easy enough if you have an accurate line counter and a scale.  Just spool up some line, weighing the spool before and after. Divide the weight by 200 and the will give you the PE.

There is an incentive to cheat a bit as a company could theoretically make a 250 denier line and advertise as a stronger PE 1 than the competition.

Changes in the original post are in blue.  Sorry for any confusion.

-J

[jurelometer]

Yeah... I just got back from Japan, and had to figure this out on the spot.

As it happens, one of the things I bought just happens to be Veritas leader line, quite clearly marked as 80 gou and diameter 1.48 mm.
When I got home and measured it, it turned out to have a diameter of 1.57mm, which as we now know is more like 90 gou.
The line itself is very nice and looks and feels like high quality stuff.
So I can only imagine that human error was responsible... that whoever was at the factory that day drew 50 meters off a bulk spool and accidentally popped it into the wrong bag.
( I don't mind at all. A bit of extra strength is totally okay. Great price too. )
I also bought 50m of 80 gou fluorocarbon, which was quite accurately 1.48mm in diameter.

Braided line is of course harder to measure. But, in the case of hollow core, its thickness can be measured by inserting something of known diameter and measuring that. In this case, a 1.2mm monofilament in the hollow core gives an OD of 1.6mm. Thusly, it can be deduced that the hollow core has a wall thickness of 0.2mm. However, that says nothing at all about the quality or density of braiding or anything else, really.
This happens to be 200lb Diamond Braid, labeled as 0.80mm diameter.

Ahh, nothing better than real world data:

First of all- I agree. As much as we want to have a braid "diameter", it is just not a meaningful measurement for braid. Sort of like asking what the diameter is for a quart of molasses

 I also think that you probably have a mislabeled coil.  Easy  enough accident to happen at a tackle shop.

As per actual mono diameter:

It is important to measure in more than one direction, as extruded line will not be perfectly round (I run into this in 3D printing all the time - it changes the volume per mm of filament, which can screw up a print). 

I just measured some 60 lb Ande nylon leader listed as 0.80, and it went from .78 to .82 mm as I twirled it around.  so right at .80 if you average it out


Just tried some other leader material of various brands (no JAFTMA numbers) that I have lying around, and they were all pretty close to the stated diameter if you average the measurements.


Here is the JAFTMA standard for solid (monofilament) lines:
https://www.jaftma.or.jp/standard/pdf/nylon.pdf

1 The standard thickness standard for nylon yarn, fluorocarbon yarn, and polyester yarn is set to Appendix 1 as the standard diameter.

2 The allowable range of nylon yarn, fluorocarbon yarn, and polyester yarn is that the upper and lower diameters are It shall not exceed the standard diameter of the pattern. However, the actual diameter shall be as close as possible to the standard diameter.

3. Strength, etc., shall be left to the discretion of each company.

4 The standard diameter measurement method is the average value measured from three directions at one point of the product.

The Google translation is not quite clear, but does not fall into "My hovercraft is full of eels" territory, so still useful.  I interpret this to mean that all measurements should be under the specified diameter, and that the line should be reasonably round.  And they get to make up whatever test strength that they want

-J

[gstours]

  Thanks      "My hovercraft is full of eels"                                       

[gstours]

Many of us have a hard time understanding the difference of the language interpreter.
  Let alone the scientific explanations in all the variations of braid lines.
     Your information here is helpful.   We are on a learning curve.

[MexicanGulf]

Interesting, I read the whole thing in one go.