Learn how to splice!

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Up until today, you’ve observed with respect and wonder this elegant assembly of rope strands that constitutes a splice... Well, that’s normal: it wasn’t you who made them. However, it is very useful to know how to make them. A splice has many advantages over a simple knot. First of all, we can't undo it anymore. This avoids any malicious acts. Secondly, the rope retains its full strength, while a knot can cause a loss of 30 to 50% of the breaking load; and there’s no chafing, thanks to the thimble. Another advantage: a neatly-tapered splice will easily slide through your bow-roller, where a knot might get stuck... and come loose again. We’re thinking here about the chain/rope join for the anchor rode. A specific splice exists for this, and we’ll be covering that in a future article, which is even better adapted to passing through the bow roller, but the rope and chain become an integral unit, without the possibility of quick disassembly. There are a few points to note before buying rope: For a small multihull of 5 to 6.50 m (15 - 20’) or for a tender, use 10 mm (⅜” diameter) rope and 6 mm (¼”) chain. From 6.50 to 9 m (20 – 30’), switch to 14 mm (”) line with 8 mm (“) chain. From 9 meters (30’), we opt for 18 mm (¾”) and 10 mm (⅜”) chain. Your rope can be made of polyester or polyamide. The former is more flexible and a little more expensive, but less resistant than the latter. For a diameter of 14 mm (”), for example, polyester breaks at 3.12 t compared to 4 for polyamide. Splicing can also be done without a thimble. This then allows a "tailor-made" adjustment for your docklines. Your multihull is quicker to moor up, and the cleats are less loaded.

Polyester or polyamide? Even when new, you can recognize the second one, as it’s already stiffer. And it doesn't get any better with time. Splicing is easier to achieve with polyester. But polyamide retains two significant points in its favor: it is 30% stronger and much cheaper: € 2 to 3 per meter in 14 mm as opposed to € 3 to 4 for polyester.

Plastic or stainless?  

Plastic or stainless? The first is cheaper, but it is more sensitive to shocks. After a violent gust of wind, it is not uncommon to find a "marked" thimble. For exposed anchorages, opt for stainless steel, which is much more resistant.


Using a fid or a pair of scissors - if you have chosen polyamide, separate the three strands and make sure that their ends are clean and smooth. Fix the desired length with tape.


With the fid, pass under the strand with the line closest to you, level with the tip of the thimble, so as to prepare for passing the first strand, the one above will fit. Insert it into the splice, then pull the tool out and tension this first strand. 


Do this again with the second strand, turning a quarter turn, in the same direction as the first. The fid is again used to open up the space for passing the strand. Be careful not to put it through under the same place, but under the second ...

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