Lines for Spearfishing

Lines for spearfishing

First, let’s look at the different materials used to make lines for spearfishing.

Dyneema & Spectra

Dyneema and Spectra are both high-performance materials commonly used in a wide range of applications, including the marine industry, outdoor sports, sport fishing, and spearfishing.

Dyneema and Spectra are both registered trademarks for high-strength polyethylene, with Dyneema produced by the Dutch company DSM and Spectra by the American company Honeywell.

Chemically and structurally, they are very similar. For obvious reasons, Spectra is more popular in the United States, while Dyneema is more popular in Europe.

Both materials are extremely strong, lightweight, and highly durable. They have very high tensile strength, even greater than steel (Dyneema is 15 times stronger than steel at the same weight). They are also highly resilient and offer excellent resistance to abrasion, UV rays, and weathering.

A Dyneema line is made from high-strength polyethylene fiber (UHMWPE). This high-molecular-weight fiber offers extremely high tensile, cut, and abrasion resistance, as well as outstanding durability, flexibility, and buoyancy. The line may consist of individual unidirectional fibers or braided strands, depending on the application specifications and strength requirements.

There are various types of Dyneema fiber, for example: SK75, SK78, SK90, and SK99.

SK75 and SK78 are the most widely used Dyneema fibers thanks to their excellent value for money.

SK99 is the highest-grade Dyneema fiber and delivers unprecedented breaking loads with almost nonexistent elongation at break.

Polyester

Polyester lines are made primarily from polyester filaments braided together. Polyester is a synthetic material known for its resistance to weathering, sunlight, and saltwater corrosion.

Polyester lines are commonly used in a wide range of applications, including boating. However, compared to Dyneema, they have a low breaking load, greater stretch, and, above all, significantly lower abrasion resistance.

Polyester lines are the budget option for spearfishing lines.

Nylon

Nylon in braided line form is less suitable for spearfishing because this material tends to absorb moisture, can degrade more quickly under prolonged UV exposure, and is highly elastic.

By contrast, nylon in monofilament form is an excellent material, widely used in surface fishing, but also in spearfishing to connect the final passes of a speargun shooting line. In this format, however, nylon does not fall under the line category; you can find it in our section dedicated to speargun rigging.

Line properties

Choosing a spearfishing line is an important step in ensuring the success of your fishing trips. There are several factors to consider when choosing a spearfishing line, including: breaking load, abrasion resistance, and stiffness.

Breaking load

The breaking load of a line is a fundamental parameter that determines the maximum strength (in kilograms) the line can withstand before failing or breaking in an ideal environment. This parameter is very important in many applications, including marine use.

The breaking load of a line is a crucial parameter that affects the safety, reliability, service life, and versatility of the applications in which it is used. It is therefore essential to know this value, but contrary to what is commonly assumed, breaking load alone is not the primary indicator of a line’s strength.

In real-world conditions, lines are subjected to stress at various contact points. It is common for a line to come into contact with edges, corners, or potentially sharp objects while under tension. In 99% of cases, failures occur at these points, due to abrasion of the line under load.

There are lines that, despite having a theoretically lower breaking load, are much more resistant to breaking at contact points, thanks to the line’s construction characteristics.

The breaking load and abrasion resistance of a line are two factors that, regardless of construction type, increase as diameter increases. However, a larger diameter negatively affects a line’s hydrodynamics and bulk. On the other hand, thinner lines can offer better water penetration and greater sensitivity, but they may be less durable and break more easily.

Abrasion resistance

The abrasion resistance rating of a line is often given too little consideration. People tend to focus mainly on breaking load (because it is easy to measure), but this is a mistake because abrasion resistance is the most important characteristic of a line intended for spearfishing. In fact, only lines with high abrasion resistance can withstand breakage under tension in real-world conditions.

Certain materials and construction techniques provide superior resistance to abrasion and therefore to breakage at contact points, such as our high-performance Hi-Tech Lines.

Breaking load vs abrasion resistance

Ultimately, for spearfishing lines, is pure breaking load more important, or abrasion resistance? The answer is simple: abrasion resistance.

Stiffness

Line stiffness may be desirable or undesirable depending on the application. In spearfishing, for standard applications such as reel line, shooting line, or wishbone line, high stiffness is considered a quality feature.

How are high levels of stiffness achieved? Stiffness is given to the line by the type of construction or through “waxing,” meaning a polyurethane treatment that impregnates the line and gives it greater stiffness, or by a combination of waxing and construction.

Line construction

There are two basic construction types for spearfishing lines: braided construction and jacketed line. Let’s look at the differences between these two structures.

Braided line – without jacket

Braided construction involves intertwining the filaments that make up the line into a certain number of carriers. The carriers are the strands that form the braid.

Usually, lines intended for spearfishing range from 4 up to a maximum of 12 carriers. The higher the number of carriers, the smoother the surface of the braided line will be. In addition, lines with more carriers are easier to “splice” or “eye splice.”

With this type of construction (braid), using the same material and diameter, the highest breaking loads can be achieved, but abrasion resistance is lower than with jacketed lines.

Braided / unidirectional line – with jacket

The construction of this line is based on the filaments that make it up (braided or unidirectional) being protected by a protective “jacket” (or sheath). The protective jacket is simply another braid with a high number of carriers and a pitch designed to create a hollow space inside. This space accommodates the core, made up of a braid or a bundle of unidirectional filaments.

This type of construction therefore combines two elements (two lines): the core and its sleeve.

Core and sleeve can be made of filaments of the same material or different materials. In spearfishing line, Dyneema and polyester are the materials used most often.

In sleeved lines, with the same material and diameter, breaking loads are slightly lower, but abrasion resistance (and break resistance) is significantly higher than in lines without a sleeve.

Types of spearfishing lines

We can divide spearfishing lines into 4 basic groups: polyester lines, Dyneema lines, Dyneema lines with a polyester sleeve, and Dyneema lines with a Dyneema sleeve.

Polyester lines

Polyester lines are the most economical choice for spearfishing. Polyester does not have the abrasion resistance or breaking load of Dyneema, but for most applications these lines can still meet the minimum requirements of spearfishing and are successfully used by many spearfishers in all situations where high strength is not required. Their construction is usually a single braid without a sheath, although in some cases lines with a sheath are available.

Dyneema lines

Their construction is a single braid in 100% Dyneema. These lines are strictly sheathless and can be made from different types of Dyneema filaments. They are definitely a premium choice.

In most cases, you will have a mid- to high-priced line made from Dyneema SK75 or SK78 microfilaments. Alternatively, there are extra-high-end braids built with the highest grade of this fiber, Dyneema SK99, where the breaking load reaches maximum levels. Depending on their construction, 100% Dyneema braids can allow connections to be made by splicing.

Dyneema lines + polyester sleeve

The classic Dyneema line with a polyester sleeve is one of the most popular options among spearfishers.

Usually, the core consists of a Dyneema braid covered by a high-carrier-count polyester sheath, very commonly with a contrasting tracer color (for example, a white line with a black tracer).

The combination of these two materials creates a line that offers good performance in terms of breaking load and abrasion resistance, while keeping costs down. It is suitable for most applications.

Dyneema lines + Dyneema sheath

These lines represent the ultimate in abrasion resistance.

Even though their breaking load may be lower than the declared value of some 100% Dyneema braids, in the field, these lines do not break and last longer than any other type of line. They are the most durable lines currently on the market.

This is achieved by combining a 100% Dyneema braid (or a bundle of unidirectional Dyneema fibers) with a sheath that is also 100% Dyneema.

Dyneema is the cut-resistant material par excellence, and when used to form the sheath it provides an ultra-abrasion-resistant jacket combined with a core that ensures high breaking loads.

This is therefore a high-end product, perfect for almost all applications, including textile wishbones, reel spooling, and shooting line wraps (instead of monofilament).

They are the top choice whenever maximum performance and strength are required.

Our Hi-Tech Dyneema lines represent the best the market can demand in terms of technical features, outperforming any other line on the market for stiffness and breaking strength.

Uses of line in spearfishing

Now let’s look at where line is used in spearfishing.

Line for the reel

One of the most common uses for line is spooling a speargun reel.

Any of the 4 types can be used to spool the reel.

Obviously, polyester lines will be the lowest-performing when the line is put under load, followed by Dyneema lines with a polyester sheath, then 100% Dyneema braids, and finally Dyneema lines with a Dyneema sheath, the highest-performing option for loading your reel.

Line for the shooting line

The wraps of a speargun shooting line are usually made with nylon monofilament, thanks to its stiffness, elasticity, and memory. However, there are cases where monofilament is less suitable than a textile line.

Line is preferred over monofilament whenever greater strength is required for the same diameter.

In this application, however, lines have the disadvantage of being softer than monofilament, so they tend to create more “bird’s nests” or tangles with the bands during the shot, and they are less practical when arranging the wraps between the line release and the muzzle line guide.

For these reasons, we recommend a high-performance line such as Hi-Tech Dyneema, which, thanks to its rigidity and unmatched abrasion resistance, is the best choice whenever it may come into contact with sharp surfaces, rubbing, abrasion, or large fish.

Line for making textile wishbones

Making textile wishbones for a band speargun requires the use of certain types of lines.

Many people commonly use inexpensive polyester lines or Dyneema lines with a polyester sheath, but at DEEP BLUE we believe this is a mistake.

Keep in mind that only a few centimeters of line are needed to make a textile wishbone, so the cost of the line becomes negligible. This allows you to choose highly technical lines that will ensure maximum quality and strength for the textile wishbone.

Below are the best types of line for making a textile wishbone in the various steps:

Band tying

100% Dyneema braids with diameters between 1.0 and 1.4 mm.

Loop construction

Hi-Tech Dyneema Lines with diameters between 1.4 and 1.7 mm.

Wishbone bridle construction

2.0 mm diameter Hi-Tech Dyneema Lines.

The low-diameter 100% Dyneema braid is perfect for tying the bands; it does not cut and ensures hold under any load, provided the tying is done correctly.

Hi-Tech line represents the top choice for making both the loops and the wishbone bridle. A wishbone bridle made this way will withstand the tension and continuous friction it is subjected to when we load the speargun by hooking it onto the shaft fin.

Other lines used for this application wear out sooner and must be replaced frequently, otherwise the wishbone may break during a spearfishing session. With Hi-Tech Dyneema, this possibility is virtually eliminated.

In conclusion

In spearfishing, the line is an essential accessory; choosing the right, high-quality line can make the difference between landing the fish of a lifetime or losing it.

We hope this guide has helped you learn more about the world of lines for spearfishing. If you need a free consultation, please don’t hesitate to contact our customer service team.