A Brummel splice is a strong and reliable way to create a loop in Dyneema rope, commonly used in high-performance sailing applications. In this guide, we’ll show you how to make a Brummel splice using 4mm Dyneema (TY4112) and attach it to a 2mm Tii-Shackle (A20120), which will then be used to secure a Dynamic 20 Tii-On Double Block (A2022Tii).
The A2022Tii— a dynamic 20mm tii-on block—is designed for soft attachment with thinner lines, up to 3mm is best. While a 4mm line can pass around the block, it can be difficult to rig due to the size of the opening. Instead, using a 2mm soft shackle simplifies the installation and provides a secure attachment point for the Brummel-spliced loop.
Another advantage of using a Tii-Shackle is that it helps maintain the block’s structural integrity under load. Thicker lines can exert outward pressure on the block’s body, increasing the risk of the top opening up under shock loads. A crossed Tii-Shackle ensures the load pulls inward, reducing this risk and allowing the block to operate at its designed working loads.
At Allen, we sell all the tools and components you need to complete this splice, including the rope, block, and splicing tools. Follow along with our step-by-step video and use this written guide below for reference.
You may have recently found yourself searching for replacement parts after a well-known manufacturer of marine hardware ceased trading. Whether you’re looking to restock essential fittings or replace worn-out components, Allen has you covered.
As a UK-based manufacturer with decades of experience in high-performance sailing hardware, we’ve been producing innovative and reliable products that sailors trust. Many of our existing products serve as direct replacements for those you may have sourced elsewhere, but with improved designs and materials to ensure better performance and durability.
To help you find the right solution, we’ve highlighted some of our key products below. These items offer the same functionality as those that have recently disappeared from the market but with enhancements to ensure long-lasting quality.
If you need a dependable replacement, take a look below to discover just some of the items Allen can help with to keep your boats and business running smoothly.
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