Stainless Steel Rope Thimble 4–20 mm – Metal Eye for Protecting Rope Loops

A stainless steel thimble (a.k.a. rope eye) is an indispensable piece of rigging hardware when you want to create a strong and durable loop at the end of a rope. By inserting a thimble into a rope eye, the attachment point (be it a shackle, hook, carabiner, or even a dock cleat) gets a metal reinforcement that takes the abrasion and load instead of the rope itself. This significantly extends the life of the rope and allows the eye to handle greater stress without deforming or cutting through.

Our thimbles are made from marine-grade AISI 316 stainless steel, which makes them suitable for use in saltwater environments – you won’t get rust stains on your deck, and they won’t corrode even after years of service. The surfaces are smooth and polished to avoid any sharp edges. The U-shaped profile of the thimble matches the curvature of the rope, and its two ends are close enough to hold the rope in place during use (with the correct size thimble for the rope diameter, the rope will “sit” snugly in the thimble’s groove).

Sizes & Selection: We offer a full range of sizes – from 4 mm up to 20 mm, which typically correspond to the approximate rope diameter they fit. For example:

• 4 mm thimble: for ~4–5 mm ropes (very thin cords, e.g., flag halyards, small paracords)
• 6 mm thimble: for ~6–7 mm ropes (common on small dinghies, flag poles, light painter lines)
• 8 mm thimble: for ~8–9 mm ropes (sailboat sheets, light anchor lines, general utility)
• 10 mm thimble: for ~10–11 mm ropes (standard anchor and dock lines on midsize boats ~6–8 m)
• 12 mm thimble: for ~12–13 mm ropes (heavier lines on yachts ~9–10 m, tow lines for small boats)
• 14 mm thimble: for ~14–15 mm ropes (dock lines for boats ~10–12 m, heavier anchor rodes)
• 16 mm thimble: for ~16–17 mm ropes (for yachts 12–14+ m, high-load lines, some industrial uses)
• 18 mm thimble: for ~18–19 mm ropes (for very large yachts, industrial slings)
• 20 mm thimble: for ~20 mm ropes (largest – used with extremely thick ropes, often in commercial marine or superyachts)

When selecting a thimble, it’s important that the rope fills the groove as much as possible – that way it won’t wobble or get pinched. If your rope is between sizes, it’s usually better to go with the larger thimble. All our thimbles meet standard size criteria and can also be used with wire rope (steel cable) if needed, though in such cases specific standards (like DIN 6899) apply; but here we’re focusing on soft (fiber) ropes.

Installation: Installing a thimble in a rope eye is usually done by splicing the rope’s end around it. For instance, with three-strand rope, you’d unlay the end and weave it back around the thimble – creating a secure eye splice. In DIY or lower-load scenarios, one might also use a strong knot (like a doubled overhand or figure-eight) or special rope clamps (especially with wire rope) to hold the thimble in place. The thimble should fit snugly – when the rope loop is made, the thimble stays in the eye, and the rope tightly encircles it. Once installed, when you attach a shackle or hook through the thimble, all the force will bear on the metal, while the rope is protected in the thimble’s cradle.

Applications: This product is used any time you have a rope that ends in a loop which will be frequently used or under substantial load. A few examples:

• Anchor ropes: At the end of an anchor line that connects to a chain or directly to an anchor – a (stainless) thimble provides a reliable spot for the shackle to the chain.
• Mooring lines: Splice a loop with a thimble for quick attachment to cleats or bollards – no wear on the rope even against rough hardware.
• Towing bridles and lines: When towing another boat or in watersports towropes – thimbles protect the rope at the hitch point from wearing through.
• Rigging: In guy-lines, tackle systems, running backstays – anywhere a rope loop attaches to a hard fitting and needs reinforcement.
• Industrial slings: If making lifting slings out of synthetic rope, thimbles are mandatory at the ends where the hooks attach.
• Others: In the garden or playground – for swings, hammocks (the metal eye at the ends prevents the rope from chafing on hooks), flagpole halyards, and so on.

By choosing our stainless thimbles, you ensure that when you put in the effort to splice an eye, it will be as durable and reliable as possible. In combination with suitable shackles, hooks, and carabiners (also stainless), you get a fully corrosion-proof system that won’t let you down at sea or on land. Trust this time-tested accessory – the rope thimble has been part of marine hardware for centuries, and our stainless versions enhance that tradition with modern materials and precision manufacturing.