How Climbing Ropes Are Made?

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How Climbing Ropes Are Made?

How Climbing Ropes Are Made? Mar. 14, 2023

How Climbing Ropes Are Made?

What are climbing ropes made of that allows them to take a beating and catch a full human mid-flight over and over? 

Well, we were wondering the same thing so we looked into the process of making climbing ropes, and it is actually pretty simple. 

Want to know how climbing ropes are made and what they are made of? 

You are about to find out! 

 

How Climbing Ropes Are Made

 

Without climbing ropes, the sport of rock climbing as it is today would be impossible. 

Even free soloing, no one just starts free soloing; they train with ropes first. 

Did you know that most brand new climbing ropes have a breaking strength over 2000 kilograms (more than most vehicles weigh)!?

That’s incredible, right? 

Basically, with the right system, you could haul your #vanlife camper vehicle extraordinaire up to Peanut Ledge with your poop-tube and some margaritas for a night of vertical comfort. 

Maybe not. But, climbing ropes are pretty darn strong. Which leads to the question, what makes them so strong? 

We were wondering that too. So we thought we would do a little digging and help answer these age-old questions: 

 

What Are Climbing Ropes Made Of? 

 

Climbing ropes are made of synthetic Polyamides. There are many different types of polyamides, both synthetic and non-synthetic. 

Naturally occurring polyamides include sheep’s wool and silk. 

The material used to make ropes—a synthetic polyamide—is most commonly known as Nylon. 

Nylon changed everything from clothing to rigging and was patented by DuPont in 1935. By the 1940’s people had started using nylon in climbing ropes. 

The Material

 

Polyamides can be made from a material called Caprolactam or from Oil. 

Nylon comes in many different types which are number coded—Nylon 10, Nylon 10.10, Nylon 6, etc.—but the type of nylon used for most climbing ropes is Nylon 6.6 or Nylon 6. 

If you are interested in geeking out on the chemistry, the chemical formula for Nylon 6 is: 

 

And looks like this: 

 

Due to its strength and stretch properties, while also being extremely light, nylon is an ideal material for making strong-dynamic climbing ropes. 

This material is made into tiny fibers that are spun into threads which are then spun into strings and so on. 

As we will discuss in more detail below, both the core and sheath of a rope are made of the same nylon. 

Depending on how nylon is woven together it will have different properties. 

Abrasion resistance and durability for example with a sheath material. Strength and stretch for a core material. 

More on this later. 

First, a momentary glance behind us. 

It Wasn’t Always This Way: A quick history of sketchy pre-nylon ropes

 

As mentioned above, DuPont first patented nylon in the mid-1930’s. Not long after, sometime in the 1940’s, nylon saw its first cliff face.

Before this era, ropes were generally made from plant-based materials braided into cords like this: 

 

In early times, ropes were made of woven grasses or vines.

Later the fiber of Hemp plants was used. Most ship ropes like the ones in Pirates of The Caribbean were made from hemp dipped in tar. 

As machine processes advanced hemp ropes became stronger due to better braiding techniques. 

Climbers soon started using braided hemp ropes during their ascents. 

In fact, even during the historic Everest summit of 1953 hemp ropes were used as fixed lines while the newer and better nylon ropes were used for all other purposes. 

While they weren’t all bad, fiber and hemp ropes had some critical draw-backs. 

Old Ropes Were Not The Best

 

First, they were heavy. 

For example, it was estimated that a single sailing ship in the 1800’s might have required over 50,000 Kilograms of hemp rope. 

Second, hemp ropes don’t have much stretch. 

Part of what gives modern ropes their strength is their ability to stretch.

This stretch distributes force, which in turn increases strength (more or less).

During climbs it was not at all uncommon for these heavy unforgiving ropes to break with a fall or when weighted over edges. 

Third, they were very annoying to handle. 

Because all ropes were braided they would coil dramatically and cause spin when suspended. 

So, as per usual, someone combined the past with new technologies to make something better. 

Kernmantel: The holy grail of rope making

 

In 1935 DuPont unleashed nylon unto the world.

By the 40s nylon was being used in all kinds of ropes. And, in 1953 Edelrid developed the first ‘Kernmantel’ rope which revolutionized ropes for use in falls. 

The Kernmantel Rope

 

Today, Edelrid still makes some of the best climbing ropes out there. Tommy Caldwell is an Edelrid ambassador and uses their ropes.

Edelrid is a German company and ‘Kernmantel’ is a German word. 

‘Kern’ means core and ‘Mantel’ means sheath. 

With the use of nylon Edelrid was able to create a strong core surrounded by an abrasion-resistant sheath. 

When combined in this way Kernmantel ropes were much more dynamic and durable, making them both stronger and safer. 

The Kernmantel was released to the public in 1964. Edelrid continued innovating and by 1966 they had released the first dry rope.

Today, practically every single climbing rope out there is a kernmantel rope. 

How Are Climbing Ropes Made? 

 

Ok, now we know what climbing ropes are made of and where they came from. Let’s get into the cool stuff! 

We are going to go in-depth about how exactly climbing ropes are made step by step:

 

 

For a visual lesson, watch Adam Ondra take you on an informative tour of the Tendon rope factory:

 

 

 

Nylon

 

As mentioned previously, all ropes start out as tiny nylon fibers. 

These fibers are spun up together into yarns. Next, multiple yarns are spun together to form larger strands.

Every part of the process is done under tension. As such, the strands are spun under tension onto large spools called ‘packages.’ 

These strands will become the core of the rope. 

 

Source image: Tendon Ropes

 

Heat

 

Next, the nylon needs to be heat treated. 

The packages are un-spooled into loose ‘skeins’ (basically neat piles).

By un-spooling the strands the heat is able to penetrate the fibers more evenly and effectively. 

In most manufacturing this part of the process is done in a giant autoclave that looks like this: 

 

 

Beal uses its own method for this step. Putting the loose strands through a pressurized heat process that accomplishes the same thing in 2 minutes versus the usual 2 hours. 

 

 

Heat process @ 2:30 min.

 

During this process, the structure of the fibers is altered as they shrink into themselves. 

Heating of the nylon is what gives it the necessary stretch and recoil that is critical for rock climbing ropes.

Impermeability Or Dry Treatment

 

Nylon in its natural state is hydrophilic, meaning it likes to absorb water. 

Studies show that a wet rope can lose anywhere from 20-50% of its strength or more. So, keeping your rope dry is important. Keeping the core, the most critical part of your rope dry is essential. 

Watch a wet rope being fall tested in the video below: 

 

 

 

The wet rope breaks much easier than a dry rope. This is why ‘dry’ ropes are generally considered higher quality. 

After being heat-treated the strands that will become the core are run through an impermeability or impregnation bath where they are treated with chemicals to help repel moisture and dirt (the sheath is treated later in the process). 

Anyone heading out for a mountain or alpine route should be using a dry rope if they want a higher degree of safety. 

The Core

 

The majority of the force exerted on a rope is absorbed by its core. It is estimated that the core accounts for ~80% of a rope’s strength.

After being heat-treated, nylon strands are spun into thicker strands. 

Multiple thicker strands are then spun together followed by their spinning with other thick strands. 

Spinning

 

Much of a rope’s strength is determined by how its strands are spun together. 

Rope fibers are spun tighter or looser or in one direction or both. 

All of this is taken into account when designing a rope for a specific use. 

For most dynamic climbing ropes the core consists of multiple thick strands each spun in different directions. 

 

Image source: Wikipedia

 

Spinning in different directions helps prevent the rope from twisting, especially when weighted or hanging. 

When you fall or hang on a well-made rope you don’t spin is space. Instead, the tension is neutral and your weight hangs evenly. 

This is a direct effect of how the core is put together. 

The Sheath

 

That colorful outer shell that takes a beating is made of the same nylon as the core.

Sheath strands are treated and dyed to have a rougher feel. 

Strands are then woven into long loosely knitted tubes.

Those tubes are then heat-treated, un-sewn, and put onto spools under tension. 

Sheath Proportion

 

Your sheath accounts for ~20% of the rope’s strength and is a key factor in protecting the all-important core. 

Depending on the type of rope you have and it’s intended use, the percentage of the rope made up of sheath will vary. 

This is called the ‘sheath proportion’ or ‘percentage of sheath’ and will be referred to in the manufacturers’ specifications on most ropes. 

For example, lighter-thinner double ropes might have a lower sheath proportion while single ropes intended for long big walls would have a much higher sheath proportion. 

In most cases, higher sheath proportion will also mean a thicker-heavier rope. 

Putting It All Together

 

Next, the core strands and sheath strands are again set under tension as they are woven together in the desired configuration. 

The entire rope is then run through another impermeability bath to treat the sheath for water repellency. 

Safety

 

Once the rope is complete a section is sent for standardized safety testing with the UIAA.

The standard testing process (for a single rope) consists of tying off a 9-foot section of rope to an 80 kg (176 lbs.) weight which is then dropped straight down from 15 feet above the rope. 

Drops continue until the rope breaks. 

Both drops endured, and impact force, are recorded. 

To pass the test a rope rated for single use must:

 

  • Hold at least 5 drops without breakage
  • Have a dynamic elongation less than 40%
  • Reach a peak impact force less than 12 kN

 

The forces exerted in a testing lab are generally much higher than would occur in an actual climbing situation. 

To learn more about fall force read here.

Remember, the number of falls listed on ropes label does not necessarily correlate with strength (i.e. more falls before rope breakage doesn’t imply a stronger rope).

After receiving a passing mark and their fall rating a rope is then ready to be cut to the desired length, labeled, and packaged. 

Summary

 

To summarize, modern climbing ropes are made of nylon in a Kernmantel formation invented by Edelrid mid-20th century. 

Nylon is stretchy and strong. 

Fibers are spun into strands which are spun into ropes. 

Ropes stretch and strength depend on how the strands are heated and wound during the manufacturing process. 

The core accounts for ~80% of rope strength. 

Sheaths are the strong outer shell. They can vary in thickness and density. 

Nylon ropes lose a considerable amount of strength when wet so dry treated ropes are best. 

Testing is standard on each rope length before being released for sale. 

Ropes are amazing.  

 

Well, this has been another installment of Now You Know!

If anyone ever asks, “Hey, what do you think climbing ropes are made of?” You will be ready with an in-depth answer because now you know. 

So get out there, rope up, and take some whippers! 

What is Climbing Rope Made Out of?

The rope is one of the most important safety aspects of rock climbing, a good rope can save your life on a fall. Have you ever wondered what makes it strong enough to catch your fall? Have you ever played with the rope and looked and the ends and the sheath and wondered what was inside?

 

Climbing rope is made from nylon fibers that are braided and wound tightly together. This makes up the core, which is the part you can’t see, but it makes the rope strong.  The colored outer portion is also made up of woven nylon, but a flatter and smoother type, and is called the sheath. The core is what makes the rope strong and stretchy, and the sheath protects the core.

Nylon is used because of its strong abrasion resistance, durability, strength, and its elasticity. Many companies make rope and all must pass safety tests. How is climbing rope made? Where is climbing rope made, and who makes it? Why is it safe? Read on for answers to these questions about one of the greatest sport’s main piece of equipment!

 

 

Types of Climbing Rope

 

Remember that there are 2 types of rope: Static vs Dynamic. Static ropes don’t really stretch because they are designed to carry a load, not to softly catch a fall. Static ropes are generally used for caving, canyoneering, rappelling, and also work well with ascenders. Dynamic ropes are able to stretch, they have a little bit of give to provide a cushion to a falling climber to soften the impact. This provides protection for the climber and doesn’t compromise the rope’s integrity.  Read our post here about the types of rope and the different diameters of climbing rope.

Climbing ropes are dynamic ropes. These ropes are constructed in what is called a kernmantle rope involving 2 parts: the core and the sheath. The sheath is the colored outer part of the rope, and the core is the inside white portion that makes it strong.

 

 

Climbing ropes used to be made from hemp and other materials and then the answer to a stronger, more durable rope material was found in a very different sport… sailing! The ropes used on yachts and sailing boats were found useful in climbing and other rope sports for their durability and strength. Today climbing ropes are made to be a lot stronger than materials used in the past for better protection and better ability at doing tougher climbs.

The Inside of a Climbing Kernmantle Rope: 

The core is made up of 10-15 nylon fibers that are tightly wound together. These make up most of the rope, the thick white inner portion. You can slightly imagine what this looks like if you look at the end of the rope. The twisted nature of the core allows it to stretch and catch a climber’s fall without giving us whiplash.

 

The sheath is the colored portion on the outside of the rope that you can see which forms the protective layer around the core. It is made of smoother, colored nylon that allows the rope to have some stretch. Kernmantle ropes can stretch quite a bit, even up to the maximum 40% elongation.

 

 

What is Nylon?

Climbing ropes are made out of nylon, so what is nylon? Nylon is a plastic, silky-like material that can be processed into thin fibers. Nylon has good elasticity, resiliency, and can protect against a good amount of friction. These properties make it great for climbing ropes!

It can also withstand hot temperatures, and protects against mildew. Insects, heat, and water could potentially do damage to nylon climbing ropes, if not well taken care of. I have never heard of insects hurting someone’s climbing rope, but all the same you should care for, and store, your rope carefully. As for water, nylon can absorb water which increases its elasticity.

 

How are Climbing Ropes Made?

Machines do all the work in making climbing ropes, making the process fairly quick and efficient. Thousands of nylon fibers that are thinner, but stronger, than human hair are used. First, these white nylon strands are twisted and then woven together to create a thicker yarn. About 10-15 of these pieces are wound together to create the core of the rope. The core is created first.

 

Machines coat the strands with a protective coating and hold the nylon fibers at an appropriate tension for each individual fiber while being wound together. Next, for the sheath, dozens of colored nylon strands are braided around the white core. The ropes are checked for flexibility and strength and then find their way to rock climbers!

Who Makes Rock Climbing Rope? Where is Climbing Rope Made? 

The major manufacturers of climbing rope include companies you may have heard of such as PMI, Mammut, Sterling, Beal, Maxim, Edelweiss, Petzl, Millet, and Black Diamond. These companies make their ropes in the USA, Switzerland, France, Germany, Spain etc. Not all ropes are available from online retailers, so you might want to try your local specialty retailer if you are looking for a good rope. And vice versa! The US doesn’t sell all of the quality rope that Europe has to offer, and you may find some of these by looking online.

 

How Heavy are Climbing Ropes?

You might be interested in knowing the weight of a rock climbing rope, especially if you have to carry it for a longer hike to the crag. The weight of a climbing rope is largely determined by the diameter and length. A skinnier rope is lighter than a thicker rope, but could be heavier depending on the core. The standard for rope weight is to be listed as grams per meter, so you can check when you are buying rope. If it says 59 grams/meter then you know that a 60 meter rope will be 3540 grams, or almost 8 pounds.

 

Climbing Rope Breaking Strength

Many companies make rock climbing rope and all must pass safety tests and be certified by the International Climbing and Mountaineering Federation (UIAA). This tests involves repeatedly dropping a weight on the rope until it breaks. Ropes are rated to withstand at least 5 test falls (usually more severe than regular climbers would take) before they break. There are also safety ratings regarding other aspects of the rope such as elongation.

 

All rock climbing ropes must pass the safety tests and meet certain standards set by the UIAA including weight and number of falls held. Test conditions are designed to simulate a hard fall. The strength of the rope is tested by the number of falls a rope can hold before breaking.

More and more hard falls make a rope weaker, and ropes are usually safe if they are retired after about 5-8 hard falls, depending on the rope. Ropes have to hold at least 5 hard falls before breaking (test falls are way more intense than any real-world fall). Ropes that can sustain more than 9 falls before breaking are labeled as a “multifall” rope.

In real-world climbing, ropes rarely break due to a fall, usually rope failure happens in situations where a rope has been cut or damaged from abrasion and sharp rocky edges. Avoid situations where a climber is resting their weight on the rope while moving over a sharp edge, making the rope vulnerable to abrasion while it is weighted.

 

How Much Weight Can a Climbing Rope Hold? 

Climbing ropes can easily hold hundreds, if not thousands (according to my knowledge…) of pounds. Heavy loads don’t ever seem to be the cause if a rope breaks. Impact force and sharp rock edges are the most to blame for any broken ropes.

Tests are usually performed using 80kg weights (used to represent the weight of an “average” climber), which is about 176 pounds, to see when the rope breaks. So should you be worried of the rope breaking during a fall if you weigh more than that? Not necessarily. The overall impact force, called the fall factor is the important part.

 

Hard falls are calculated by the distance you fall and divided by how much rope is out, this is called the fall factor. Most falls should be lower than a factor of one. Most ropes can survive many small falls, but the bigger falls with the higher fall factor could cause the rope to lose the ability to absorb the force of falls.

When to Retire a Climbing Rope

Each fall weakens the rope and serious hard falls can affect the strength of the rope, without you even knowing. Falls don’t create obvious outward signs of wear on the rope. A hard fall is a definition of a fall that is about 10-15 meters or more. Manufacturers often recommend that ropes be retired after an extremely hard fall.

Ropes are usually rated up to a certain amount of falls, such as 5-9 or even more. Climbers need to keep track of any falls a rope has sustained and retire the rope after about 5 falls, depending on how hard of a fall and the condition of the rope.

 

What is the Lifespan of a Climbing Rope? 

You need to take into consideration many different factors in order to know when it is best to retire a climbing rope. This includes age of the rope, abrasion and wear on the rope, number of falls taken, etc.

Ropes typically last about 3 years with casual use, less with more use, and more with less use. If you never use your rope, it will probably last about 10 years, but if you use if often it might last less than a year. This is based on the material strength and if it lessens with age.

How to Inspect a Climbing Rope

Before use, test ropes for stiffness, flat spots, and places where the core is shot. Stiff ropes have lost their elasticity. Flat spots mean there is something abnormal and deformed with the core.  When the core is shot it means that the sheath is starting to be rubbed through so you can see the white core of the rope. This makes the rope less safe to use.

 

Be smart, It’s best to be careful and not use a climbing rope that is old, fraying, and weak. Invest in some new ropes every so often because this is your life you are dangling from that cliff!

 

What are Climbing Ropes Made of? • Climbing Blogger

Three things are certain in life: death, taxes, and the thrill of rock climbing. If you’ve ever climbed, you know that nothing beats the thrill of scaling an imposing rock wall. But have you ever stopped and thought about what makes it all possible?

In this guide, I’ll examine exactly what it is that your climbing rope is made of. You may be surprised to learn that your rope consists of different parts—with different compositions. In general, it’s important to understand the different parts of your rope and their unique structures.

Let’s take a look at these parts one by one so that you can gain a better understanding of your rope.

 

Rope Parts

 

To begin with, let’s take a look at how climbing ropes are constructed. For this piece, we’ll discuss dynamic ropes, as these are the ropes climbers use for lead climbing purposes.

What are the two different parts to a dynamic rope? First, you have the core. The core constitutes your rope’s strong foundation. It serves as the backbone of your rope and gives it the strength and elasticity you need to climb.

Second, your rope has a sheath. The sheath serves as the colorful, outer layer of your rope. Furthermore, it functions as a protective layer, guarding the core of your rope from damage.

Understanding the different parts to your rope can help you keep better rope maintenance, so let’s take a look at what these two rope parts are made up of.

 

Core Construction

 

What is the core of your rope made up of?

Specifically, most dynamics ropes contain between ten to fifteen nylon strands that are woven together to form a durable elastic rope foundation. Generally speaking, the core of your rope will be white, though you likely won’t see too much of this core unless your rope is damaged (in which case, it’s time to upgrade your rope).

So the core of your rope consists of around fifteen nylon strands. Pretty simple, right?

Not exactly. As it turns out, a lot goes into the making of this woven nylon. First, one nylon string consists of thousands of nylon fibers being twisted together. Rope makers braid three of these strings together. The result of this braid is just one of the fifteen nylon strands that are used in the construction of your rope’s core.

What does this mean?

Simply put, it means that your rope is pretty durable. Though it may not appear to be much on the surface, the core of your rope consists of thousands upon thousands of nylon fibers that give it the strength to keep you climbing for years.

 

Sheath Construction

 

You may be wondering, “Is my rope’s sheath made the same way?”

The answer is “No.” As it turns out, your rope’s sheath consists of a much simpler composition. Specifically, because the sheath of your rope functions as an elastic, protective layer for your rope’s core, it requires a different composition.

To begin with, dynamic rope sheaths are typically woven around the core of your rope. Rope makers weave nylon strings around the core of your rope to build the sheath. In general, these nylon strings are much flatter than the ones found in the core of your rope because they aren’t twisted together.

These flatter nylon strands allow your rope to have greater elasticity. In fact, according to some measures, they can enable your rope to stretch up to forty percent.

 

Why Nylon?

 

Now that you know the general composition of your climbing rope, let’s tackle an important question: why nylon?

Specifically, there are several advantages in using nylon to manufacture climbing ropes. For starters, nylon resists friction and wear and tear much better than other rope-making materials. It also allows for greater elasticity and resiliency while climbing.

How resilient is nylon, exactly? To put it mildly, nylon fibers can retain their efficiency for up to ten years if left dormant. This means that you could feasibly use a climbing rope up to ten years old if it’s left packaged.

That’s pretty impressive for a material that’s naturally thinner than human hair.

For these reasons, nylon is the predominant material in dynamic climbing ropes. It’s helpful to envision nylon as a stretchy, plastic-like substance (even if that’s not how your rope feels).

As you might expect, climbing ropes are machine-made and heavily tested before being packaged and shipped. Remember to check your rope’s packaging upon purchase to see just how long your rope’s lifespan is. Often, you can check this information as well as specific composition details when you purchase your rope.

 

Climbing Rope Weight

 

Knowing this, how heavy is a climbing rope?

If you’ve never climbed before, you may be wondering just how heavy those woven nylon fibers are. After all, we’re talking thousands of fibers—and that’s got to be a lot of weight, right?

Actually, wrong. Despite the fact that your rope consists of countless fibers, strands, and strings, most climbing ropes average less than ten pounds (about 4,5kg). This means that you can comfortably carry them across your crag and enjoy your climbing trip.

 

The Bottom Line

 

In closing, your climbing rope may be more than meets the eye.

What may appear simple on the outside actually results from an intricate process that links together thousands of tiny nylon fibers into an efficient product that can suspend hundreds of pounds.

To recap, your dynamic climbing rope consists of two different parts: the core and the sheath. While both of these parts are formed from woven nylon strands, the process for making each differs significantly.

In the manufacturing process, these two parts come together to form a product that is durable and can keep you climbing for years.

So don’t worry! Whether you are new to rock climbing or are an experienced climber, you can be sure of one thing: your climbing rope is truly something special.

That means it’s time to go on your next climbing adventure! So go out, and put that nylon to the test!

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    Linda Hu: ropemaker@sdbaron.cn

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    liu yingying: luckyrope@sdbaron.cn

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