ropes for camping, winches and towing

see also:

• essential knots for campers
• going off-road / 4WD
• guy ropes

• there are many types of ropes, each have their purposes, pros and cons for a specific use case

• cotton rope - mainly used for crafts
• cotton twine
• sash cords

• a long, soft, shiny bast fiber that can be spun into coarse, strong threads and creates a firmly constructed twine that can be easily twisted into a rope that holds up against tremendous weight and friction
• primary source of the fiber is Corchorus olitorius, but it is considered inferior to Corchorus capsularis

• made from fibers obtained from the leaves of the Abaca plant (Musa textilis)
• the strongest of the natural fibers and results in hard-wearing, low stretch, general-purpose ropes which are superior to sisal in their resistance to weathering, fungal attack, and moisture
• stronger and softer feel than sisal
• good abrasion resistance
• low stretch
• 6mm has breaking strain of 260kg
• 10mm has breaking strain of 635kg
• 12mm has breaking strain of 955kg
• 20mm has breaking strain of 2845kg
• 24mm has breaking strain of 4065kg
• 48mm has breaking strain of 14800kg

• natural fibre rope made from the fiber of the Agave plant
• rough feel and often used in visual merchandising, as battling rope (eg. tug of war) and for other aesthetic uses such as a child's swing and landscaping
• 6mm has breaking strain of 230kg
• 12mm has breaking strain of 840kg
• 24mm has breaking strain of 3590kg
• elongates by 9% at break
• sensitive to mineral acids, weak or strong paints, detergents, chemical salts, fats, weathering and sunlight
• generally resistant to volatile petroleum solvents, batching oils, alkalis

• inexpensive synthetic
• harsh on your hands
• degrades quickly when exposed to sunlight for prolonged periods
• very strong and holds up well in marine conditions

• nylon kernmantle rope used for parachutes
• 30% elongation
• the yarns of the core (“the guts”) can be removed when finer string is needed, for instance as sewing thread to repair gear, or to be used as fishing line in a survival situation.
• can remove the yarn in the core and use the nylon sheath alone to make shoe laces
• ends of the cord can be melted and/or crimped to prevent fraying
• type I = 43kg breaking strain, 1 core, 16:1 sheath
• type IA = 45kg breaking strain, no core, 16:1 sheath
• type II = 180kg breaking strain, 4-7 core, 32:1 or 36:1 sheath
• type IIA = 102kg breaking strain, no core, 32:1 or 36:1 sheath
• type III aka “550” = 250kg (550lbs) breaking strain, 7-9 core, 32:1 or 36:1 sheath
• type IV = 340kg breaking strain, 11 core, 32:1 or 36:1 or 44:1 sheath

• melts at 255degC
• elongates by 20% at break
• specific gravity 1.4
• 8mm has breaking strain of 960kg
• 12mm has breaking strain of 2300kg
• 16mm has breaking strain of 3700kg
• 20mm has breaking strain of 5200kg
• polyester:
  • sensitive to alkalis, sulphuric acid
  • resistant to most organic & mineral acids, organic solvents, bleaches and oxidising agents.
• nylon:
  • sensitive to strong acids & oxidising agents, soluble in formic, sulphuric acids & phenolic compounds
  • resistant to alkalis, alcohols, esters, hydrocarbons & most bleaches

• melts at 255degC
• elongates by 20-35% at break
• specific gravity 1.38
• has very good UV and chafe resistance
• very soft to touch and will hold up will in marine conditions
• 8mm has breaking strain of 1400-1750kg and is 45g/m
• 12mm has breaking strain of 3200-3400kg and is 97g/m
• 16mm has breaking strain of 4700-5400kg and is 163g/m
• 20mm has breaking strain of 6800kg and is 260g/m
• sensitive to alkalis, sulphuric acid, phenolics
• resistant to most organic & mineral acids, organic solvents, bleaches and oxidising agents.

• marketed as Spectra for yachting / marine use
• melts at 147degC
• elongates by 3% at break
• SG 0.97 core and 1.38 jacket
• 8mm has breaking strain of 3310kg
• 12mm has breaking strain of 6000kg
• sensitive to strong oxidising agents, chlorosulfuric and nitric acids at high temperatures
• resistant to most acids and alkalis, cold alcohols, esters, ketones, bleaches.

• Aramid outer braided Kevlar tactical cord:
  • double the strength of regular tactical paracord and heat resistant to 480°C; UV resistant; rot resistant; fire resistant; low stretch;
  • 1.18mm cord has breaking strain of 145kg; ~1g/m;
    • eg. https://www.survivalsuppliesaustralia.com.au/Atwood-Micro-Kevlar-Cord-1.18mm-x-38M-Yellow
  • 2.38mm cord has breaking strain of 238kg; 4.5g/m;
    • eg. https://www.survivalsuppliesaustralia.com.au/Atwood-Tactical-Kevlar-2.38mm-30M-Yellow

• elasticised polyester cord
• hiking tents have 8-9.5mm diameter poles which are kept together as one unit by elasticised shock cord which is usually 2.5-3.5mm diameter (need 1-2' longer than the poles)
• larger tents and awning poles may use 4mm diameter shock cord
• luggage nets, tie downs often use 5mm shock cord
• 7-16mm are used for bungee cords
• rubber core shock cords
  • over time, these lose elasticity and fail needing replacement
• silicone-core shock cord
  • outlasts natural rubber and remains elastic to -40 F/C but is more expensive

• an appropriate sized winch should generally be rated to be able to pull at least 1.5x your vehicle's gross weight - depending on vehicle that usually means at least 4000kg rating
• the legal distance between 2 vehicles being towed in Australia is usually no more than 4m, but towing this way by the inexperienced should be a last resort as it is very dangerous

• Dyneema (aka ultra-high molecular weight polyethylene or UHMWPE) is one of the strongest synthetic fibres for weight, it is 1/8th the weight of steel for same strength and 20% stronger than steel of same diameter
• NB. the polyurethane coating on Chinese made Dyneema winch ropes is not as a good a quality as Dutch made
• it is UV resistant and chemical resistant
  • the larger the diameter, the more UV resistant:
    • after 12 months exposure to UV, 8mm will be at 80% strength, 6mm at 60%, 3mm at 45%, 0.5mm at 35% ¹⁾
    • after 10yrs exposure to UV, 8mm will be at 40% strength, 6mm at 25%, 3mm at 15%, 0.5mm at 8%
    • thus use additional polyurethane UV protective coating if expect extensive UV exposure times
      • this will also increases colour depth, grip and abrasion/cut resistance whilst reducing dirt ingress and staining and UV discolouration
• it is relatively non-stretch and thus will have much less recoil if it snaps
  • long periods of static loads will cause “creep” (lengthening):
    • at 16degC, 200kN load, 650gsm, SK75 will creep 2.3%/yr over 7yrs, SK78 will creep 0.5%/yr over 15yrs, DM20 will never creep.²⁾
• it is buoyant in water (SG 0.97) and relatively abrasion resistant
• melts at 152degC
• it does not kink
• for maximum strength, avoid knots as these will reduce strength by 60%
  • Instead, opt for splices as a professional splice should only lose 10% of initial strength
• most winch ropes come with a flat mounting lug with eyelet at one end to pass into the winch (eg. for a 12mm rope, 8mm flat mounting lug, for 10mm, a 6mm flat mounting lug) and a stainless steel loop eye at the other end (often 40x25mm internal) +/- snap hook
• winch extension or tow ropes may just have a soft loop at each end
  • eg. https://www.george4x4.com.au/collections/extension-rope
• fibres are graded as follows:
  • SK75
    • 6mm will usually have 3300kg breaking strain and weighs 23g/m
    • 8mm will usually have 5800kg breaking strain and weighs 38g/m
    • 9mm will usually have 8000kg breaking strain
    • 10mm will usually have 11050kg breaking strain and weighs 61g/m
    • 12mm will usually have 12000kg breaking strain and weighs 93g/m
    • 13mm will usually have 14000kg breaking strain
    • 14mm will usually have 18000kg breaking strain
    • 16mm will usually have 24000kg breaking strain
    • 20mm will usually have 34000kg breaking strain
  • SK78
    • has lower creep than SK75 making it the preferred choice for long term static applications
    • 10mm SK78 will usually have 11050kg breaking strain
    • 11mm SK78 will usually have 12800kg breaking strain
    • 12mm SK78 will usually have 14800kg breaking strain

• these are used for snatch recovery techniques
• do not use a kinetic rope on a winch or as a winch cable extension
• do not use towing balls as the recovery point they may fly off and be a lethal missile

• nylon webbing strap
• can stretch 10%-20% under load
• the kinetic energy straps store when stretched is used to pull vehicles out of sand or mud
• do not use if signs of fraying or tear
• always clean after use

• rope elongation is up to 30%
  • do not exceed over 20% elongation of the rope when pulling. Make a mark on the ground for reference if possible.
• heavy duty, but light and small enough to easily stow
• generally much stronger and more durable than the common snatch strap
• ALWAYS keep the rope clean and free from sand
• avoid tying knots when connecting rope
• avoid slack in the rope
• give it a break after 3 times pulling in a short time to recover its elasticity