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Materials used for Ropes:
Nylon (polyamide)

Nylon is a generic designation for a family of synthetic polymers known generically as polyamides

Widely used for many products, it can be spun, moulded and machined.

Nylon Physical Properties

Nylon Chemical Properties and Rot Resistance

Nylon Rope Strength and Weight

Diameter of Rope(Minimum) Breaking Strength Weight of Rope
(in) (mm)(lbf)(kN)(lbm/ft)(kg/m)
1/4 6 1805 7.61 0.016 .024
5/16 8 2730 7.61 0.025 0.038
3/8 10 3795 10.8 0.036 0.055
7/16 11 5380 14.0 0.048 0.073
1/2 12 7510 16.8 0.063 0.096
5/8 16 11210 24.8 0.099 0.151
3/4 18 14350 34.0 0.143 0.219
7/8 22 23470 46.0 0.195 0.298
1 24 32065 57.0 0.253 0.387

The safe loading of a nylon rope is a 1/10 to 1/12 of its breaking strength. Remember that knots weaken a rope as does age, wear, chemical attack etc.

Nylon Degradation

Nylon is sensitive to high temperatures and will degrade releasing toxic materials including cyanide.

It it however resistant to UV light.

Because it absorbs water it is liable to stain. This is not necessarily harmful but can be unsightly.

Nylon rope Uses

Nylon rope is usually made from long extruded mono-filament. I have not seen it being chopped and re-spun, maybe for specialty items? Nylon rope comes either braided or twisted.

It can be made from thicker or thinner strands which will affect its feel, stiffness and appearance. It can be very soft and easy to handle, or quite harsh to the touch.

Nylon can be dyed and is available in many colours. Some people who have traditional boats have dyed their nylon dock and anchor lines a browny colour to make them look more authentic. Avoid strong bases and acids if you want to try this. Do a test first.

Some nylon rope is available with water repelling coating which reduce water absorption and loss of strength.

Nylon mono-filament has been the mainstay of fishing line for many years. It is still available as monofilament:KastKing Premium Monofilament Fishing Line Various Color--- 300M / 328 Yards (White, 35LB(15.9KG)0.50mm) (it is often used by crafters as a bead stringing line or as a clear sewing thread) or as braided line: Woodstock Line NC-50-12-B No. 12 Braided Nylon Line, Black, 50-Yard

Most boat docking lines are made from nylon and are available in many sizes and colours.SeaSense Double Braid Nylon Dockline, 1/2-Inch X 15-Foot, Blue

Anchor lines for small yachts are often nylon. The natural stretch of the lines helps to cushion the boat. Both twisted: Attwood Nylon Twisted Anchor Line with Thimble (3/8-Inchx150-Feet) and braided nylon anchor lines are available Norestar Braided Nylon Anchor Rope, 200-Feet x 1/2-Inch . The twisted lines have more stretch in them but are easier to snag and damage. They are also less expensive.

General purpose towing straps are often made of nylon: Truck Car Two Metal Hook Nylon Braided Strap Towing Rope Yellow 4.5M

Advantages and Disadvantages of Nylon Rope



It's confusing that what many people call "nylon rope", a common light floating line that quickly degrades in UV light is really polypropelene. It's often yellow and very bristly to the hand.

I try to be accurate and check my figures, but mistakes happen. Check the suitability of any material against the technical information provided by the manufacturer.

email me if you find mistakes, I'll fix them and we'll all benefit: Christine [HOME]