Comprehensive University Tippet Study

Comprehensive University Tippet Study

What Material Is Between You and the Fish?

The following tippet study took place at the MSU and WCU materials labs back in 1996. I was fortunate to have access to the materials lab when I taught the fly fishing programs at Western Carolina University. The comprehensive university tippet study began with some simple assumptions about the gear we use in the stream. We wanted to learn some new things about mono and prove some hunches along the way.

This seemed of utmost importance at the time since fly fishing is serious business! The below information includes data from the studies. Many of the attributes for testing would be similar if I was to do them all over today! Huge thanks to all of the product manufacturers you see on the pages below that were so very graciously donated for this cause.

The study was conducted because all brands of mono are far from being created equal. I had my suspicions for decades as to why some were a waste of valuable money. The tippet is the weakest link between you and the fish. This was because on the stream I had seen certain monofilament fail consistently from multiple clients. Certain other brands would remain much higher quality. It really boils down to quality control of what many companies decide for market-ready leader material. One material that I use often on the water is Stroft mono. It was not included in 1995 because I did not have it available. All of the brands were sent from the manufacturers (2 samples each).

Knot Breaking Claims

Many knot books claim certain breaking strengths for particular knots. I had my suspicions about that as a teenager because various elasticities and surface finishes are bound to have radically different breaking strengths. For example, many inferior monofilaments break far away from the knot. Does that imply the knot is 100%-far from it? You have to have a clean section of mono during the extrusion process to even begin a knot study. The findings are listed below.

The tippet study was designed to test varying brands of material for levels of force required to break the tippet material with different knots, the specific gravity of the material (how well it floats), elasticity (amount of stretch), the diameter of the material (micrometer tests for size), and surface finish. The tippet used for the study was 4X (.007″ inch). The test results were all performed as a blind study by having the various brands rolled onto a separate dispenser and assigned a number ­(including the fluorocarbon materials).

Match the Mono to the Situation

The determination as to which brands to purchase will depend on the examples that you encounter. For most trout fishing examples, abrasion resistance is a minor concern compared to knot breaking strength, size, and the elasticity (stretch ratio). The advantages of increased abrasion resistance may influence your decision if you encounter sharp rocks or coral reefs. Nymphs and wet fly anglers may prefer fluorocarbon because it sinks.

Another attribute of fluorocarbon is that it stretches but does not recover to its original length over heavy loads such as in landing larger fish. It is well worth taking a second and tying a new knot after playing larger fish. Regular monofilament (co-polymer nylon) stretches and recovers more than fluorocarbon and actually holds knots better overall. It is my first choice when dry fly fishing.



The elasticity test was conducted by attaching 20 cm of material into gripping jaws and stretching the material at a rate of 50 grams\per\second until failure. The supple materials attain a greater stretch ratio before breaking. The hard mono achieved a lower stretch ratio (includes fluorocarbon materials). In general, the harder materials achieve greater abrasion resistance at the expense of also breaking easier.



The diameter results of the various tippets were performed with a Welch Scientific Company micrometer. The tippet sample readings were taken at six locations and averaged. All of the tippets claim to be .007″ inch (or .0178 cm). Maxima claimed 4x has the largest diameter-it actually measured 2x (.009″). It tests well when compared with the other brands, but keep in mind that if we tested a leading tippet from another manufacturer of the same size the results would vary.

Actual Breaking Strength


The figures were calculated by pulling the material apart at a rate of 50 grains\per\second. A spring scale by Enrich Inc.­ was used to measure the resistance where the material failed. Make sure that you view the knot data before basing your decision to purchase. This is because the brands will all hold certain breaking strengths at varying percentages. For example, you may have one material that tests a high breaking strength, yet it holds knots with a decreased percentage over other brands.


This illustrated graph shows the percentage difference of actual versus claimed break strength. There is presently no standard of compliance for these types of claims.

Specific Gravity


The lower the number indicates that the material will float higher or longer on the water’s surface. The higher the number above one is indicative of a material that will sink quickly when placed in water-­typical of fluorocarbons.

Wind Knot


The “actual” breaking strengths varied from “claimed” breaking strengths. The average wind knot breaking strengths for all of the materials lumped together is 80.33% (graph below).


Perfection Loop


The average perfection loop breaking strengths for all of the materials lumped together is 95.45%.


Triple Surgeon’s Knot


A triple surgeon’s knot is common for joining sections of leader. The average triple surgeon’s knot breaking strengths for all of the materials lumped together is 87.13%.

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Surface Finish

A clean mirror-like surface finish will aid in maintaining a higher breaking strength for all knots (pic top of the page). It also helps to reduce the rate of the nylon absorbing water. The picture (Scientific Anglers) is magnified about 350 courtesy of Ramsey Greene, MSU materials lab.


The crater-like surface finish will reduce the overall breaking strength of the material. Especially when there are lacerations across the cross-section of the material. It also increases the rate of the nylon absorbing water­ (causes it to weaken). The picture (Cortland) is magnified about 350 times actual size courtesy of Ramsey Greene, MSU materials lab.

Mono Picture Is “Worth A Thousand Words”

Often you will read that a knot holds a certain percentage of the knot strength. They are all different! The extrusion process may vary the surface finish depending on temperature, air pressure, and many other factors. Look for the brand that holds the highest breaking strength when judging the different knots.

In general, the tippets that have a lower breaking strength for the supple nylons will also fail early when used on the water. This is because the surface finish looks similar to a picture of craters on the moon’s surface. When nylon becomes wet, the lacerations (crater appearance) in the material soak up water. This process further reduces the strength of the material by as much as 30%. A material will fail even quicker when saturated with water. The surface finish may be a good indicator for judging quality when used in addition to breaking tests from a machine.

Conclusions with Types of Mono

The fluorocarbons typically offer a higher specific gravity (sinks quickly), lower breaking strength for all knots and better abrasion resistance ­may be important if you have many obstacles in the water. It also offers a slightly lower refractive index when compared to regular nylon (does not reflect light well). Many claims that fluorocarbon is invisible to fish­ (not a chance IMHO). It also costs around three times the amount of regular mono.

The regular mono typically has a lower specific gravity (floats higher), higher overall breaking strength for all knots, and a slightly higher refractive index (slightly easier to see it). Regular mono comes in hard and soft nylons. Use the elasticity chart above to make this decision when choosing your material. They both offer advantages for certain types of waters.