Nylon vs Polyester vs Dyneema: Which Rope Is Which?

There is a lot of rope in the world. Most of it looks the same when it is coiled in a heap. But the fibre inside changes everything. It decides if a rope stretches, floats, melts or holds a fall.

I work with retired climbing rope every day, so I get asked this a lot. Is it nylon? Is it polyester? Is it that Dyneema stuff? Short answer: three fibres, three very different jobs. Here is the plain version.

Nylon: the stretchy one

Climbing rope is nylon. Nylon stretches, and that stretch is the point. When you fall, the rope gives a bit and soaks up the shock. Without it, a fall would feel like hitting a wall.

Nylon is also tough and grippy. It takes a knot well. The downside is that it drinks water, and a wet nylon rope is weaker and heavier. It also takes hundreds of years to break down, which is why I am so keen to keep it out of landfill.

Polyester: the steady one

Polyester barely stretches. It shrugs off water and sunlight much better than nylon. So you see it on boats, on tree work and anywhere a rope has to stay put and sit outside all year.

It is a poor choice for catching a falling climber, because there is no give. Great for hauling. Not great for falling.

Dyneema: the strong, slippery one

Dyneema is a brand name for a very strong plastic fibre. Weight for weight it is stronger than steel. It is thin, light and it floats.

But it is slippery, it hates heat, and it has almost no stretch. That is why it turns up in slings and light kit, not in the rope that catches your fall.

Which fibre ends up in my belts?

Nylon. Every time. The ropes I get from climbing walls are retired dynamic ropes, so they are nylon inside and out. That is why they sew well, take a bend and hold colour. It is also why a recycled climbing rope belt feels so tough. It was built to catch people.

Want something smaller? A rope keychain is a fiver. Or grab a set of climbing rope coasters. Not sure what they like? Try gifts for climbers.

So next time you see a heap of rope, check the fibre. It tells you the whole story of what that rope was made to do.

Stay classy and remember,
Make Waste Useful.

George