Boat Rope
The vast U.S. cordage market allows us to have several competitive options including; Robline, New England, Samson, Yale, and Marlow Ropes, just to name a few. Each of these manufacturers provides various rope constructions utilizing different materials to allow the consumer to achieve different functions based on application. All of the jargon like Spectra, Dyneema, Vectran, Kevlar, Technora, Dacron, Double Braid, Single Braid, and Three Strand, can be quite confusing sometimes. Let’s see if we can’t help explain some of the basic differences.
Rope Fibers:
Polyester, often called Dacron, is a durable choice for many sheets and control lines. It has good UV resistance and more elastic stretch than high-modulus fibers. Finished rope performance also depends on construction and diameter.
Aramids include Technora and Kevlar. They are different fibers, not interchangeable names or a simple old-and-new replacement. Selection depends on heat, flex fatigue, abrasion, UV exposure and the construction specified for the job.
HMPE fibers are sold in different grades under names including Dyneema and Spectra. They offer high strength for their weight, very low elastic stretch and little water absorption. Heat and sustained loading matter: creep is permanent elongation under load, and its behavior varies by fiber grade and conditions.
Vectran is a liquid-crystal polymer fiber, a different material from HMPE and aramid. It is used where low stretch and low creep are useful. Check the rope maker’s guidance on cover protection, bending and UV exposure.
Rope Construction:
Double Braid, the most common type of rope construction in today’s sailboat market, is a two-part braided line, one part cover and one part core. Double braid line usually will have a polyester cover and a core made from either Dacron, Spectra, Vectran, Technora, or some sort of blend thereof. It is also possible to find blended and exotic covers.
A single braid has no separate braided cover over a core; 12-strand is one common construction. This construction can typically be found in the core of a double braided line. Single braids can be coated to add U.V stabilization if necessary. Typically single braids are not good to put your hands on because they have a small diameter relative to their load capacity and can be slippery.
Lastly, Three Strand ropes are the more traditional looking right-hand-laid or twisted ropes that we will hardly use anymore in modern applications, unless it is for dock lines at which point Nylon becomes the preferred material due to its elasticity, strength, chafe resistance and appropriate strength and energy absorption.
The way a rope is constructed, not just its material, plays a big part in how a rope performs, parallel fibers typically stretch the least, braided fibers usually provide some stretch or elasticity, and three strand line usually ends up being very stretchy and has a very elastic effect.
Hopefully this clears up at least a little of the technical jargon associated with rope. To find out what is the best product for your application needs please see your local rigger. You can read more about rope selection and maintenance here.
Leave us a comment below, we’d love to hear from you.
Click on a picture to link to manufacturers’ websites for more info.
Compare current TRC rope options such as Sta-Set polyester double braid and Endura Braid. Choose the diameter and construction for the actual loads, sheaves, clutches and handling requirements.
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Dear Sirs
I have been searching internet for information on how the rope is changed by different kinds of mantel braiding, and unfortunately I have not found any information. So I should like you to reference some information about that. Or perhaps make somebody write about it. I know of this:
The braid can be (I hope this translation from Danish is correct):
cross braid
round braid
spiral braid
There can typically be from 6 to 32 strands in each braid. The strands may be having one, two or three parallel strands side by side. The strands can be Z-laid or S-laid.
The braid can be made loose or hard.
What do all these constructions details do to the rope behavior?
Such as flexibility, strength, hand grip, bending diameter.
Thanks for asking all good questions, but I am afraid this is better suited for a rope manufacturer. Because I am also interested in the differences I have submitted your comment to the experts at New England Ropes/ Teufelberger. Let’s see what they say…
Cheers,
T.R.C.
Thanks for you reply. I look forward to an expert answer.
I did found a little more information. I think the English names of the main three used mantel braiding kinds are:
plain braid
twill braid
solid braid
And I got this reference to Handbook of Fibre Rope Technology
https://books.google.dk/books?id=B_iiAgAAQBAJ
But even this Handbook do not explain if plain braid or twill braid makes any difference to a rope.
I would find an accurate description and discussion of rope CONSTRUCTION, including a definitive description of non-cored, PLAIT (8 strand or other plaits) to be a helpful supplement to your note above. I tried to describe (without diagrams) to a ‘mate the combines use of Z and S laid strands in plaited constructions, and their relative merits for specific uses (such as docking and mooring) – but he remained somewhat unconvinced. Illustrations or diagrams would be useful too! Thanks advance… Wesley
Thanks for the comment. It sounds like you need to be a guest blogger! I’d love to hear your thoughts. Please feel free to write some of this down and send it this way. I feel like I need to learn more about different rope construction and it’s preferred uses.