Sail twine is a specialized heavy-duty cordage used primarily for repairing sails, whipping rope ends to prevent fraying, and general rigging tasks. While both waxed and unwaxed versions are available, waxed polyester is generally the industry standard for marine environments due to its superior durability and ease of use in heavy fabrics.
Sail twine sizes are often denoted by thickness in mm or by manufacturer-specific “numbers”.
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Waxed vs. Unwaxed Sail Twine
| Feature | Waxed Sail Twine | Unwaxed Sail Twine |
| Primary Advantage | Lubrication: Glides easily through thick sailcloth and rope strands without snagging. | Flexibility: More fluid movement; better for decorative knotting or crafts like macramé. |
| Durability | High: Wax protects fibers from salt, UV, and internal friction, extending life by up to 40%. | Lower: More prone to fraying and environmental degradation over time. |
| Knot Security | Excellent: Wax creates “tackiness” that helps knots and whippings stay tight. | Moderate: Can be slippery or prone to unraveling, especially with synthetic fibers. |
| Handling | Tends to tangle less as fibers stay held together; stiffer feel. | Can fray or “fuzz” during use, making threading needles more difficult. |
| Sealing | Wax helps seal the holes made by the needle, adding a degree of water resistance. | Leaves needle holes open, which can lead to moisture seepage in heavy rain or spray. |
Summary of Pros and Cons
