To Pull or Snatch?

In Articles, Technical by Glyn Demmer9 Comments

Urban legends abound when off-roading, one hears of the military type kinetic rope with magical elastic properties that simply recovers stuck vehicles all day without ever needing to rest! At the same time the debate rages around the use of kinetic straps or ropes as opposed to the use of the humble pull strap.

Well, simply put the pull strap is your first line of defence and after the spade one of the first items you buy when starting up, an invaluable item of equipment when putting a recovery kit together .Made of low elongation, high tenacity polyester with limited stretch, it is used to pull or tow stuck vehicles through or over obstacles where a degree of control is required.. After securely attaching the strap to both vehicles one should take up the slack, the recovering vehicle then moves off at a moderate pace to start the recovery. Used as the first line of defence, movement should be gentle with as few jerks as possible. Pull straps can also be used to extend a winch cable and as a tree trunk protector in an absolute emergency.

Your last line of defence will be your kinetic strap or rope. Made of high elongation, high tenacity polyamide, most kinetic straps stretch 20—25% of their length, converting potential energy into kinetic energy. This short sharp elastic rebound is used to recover an extremely bogged down vehicle from sand or mud. After pulling off sufficient practice will allow a good driver to stop before the strap stops him, thereby allowing full utilisation of the kinetic capability and not straining the strap or recovery points on the vehicles.

The kinetic energy recovery rope is used in a similar fashion to recover severely stuck vehicles from sand or mud, possibly after a kinetic strap. The rope is an ultra-high elongation, high tenacity, plaited polyamide rope and can elongate 30-40% of its length. Once used it should be loosely piled to recover its kinetic capability and not immediately packed away.

One often sees multiple use of a Kinetic strap or rope. A good rule of thumb is that, after one rigorous snatch, the kinetic capability has been utilised and the strap requires eight hours for every 10% of stretch to ‘creep back’ or be restored to its original length and kinetic capability, thus, to recover from 30% extension would require 24 hours of rest.

However, what influences the kinetic capability?

• The mass of the two vehicles.
• How badly ‘stuck’ the vehicle to be recovered is. The rope or strap utilised should be rated according to the mass of the stuck vehicle.
• Traction available to the recovering vehicle — in other words, the road surface. A speed of +- 18 Km/ph is suggested in the case of two vehicles of similar mass.
• The distance between vehicles and the speed at which the recovery vehicle moves.

As safety is paramount and one does not want to spoil a trip by injuring someone or damaging vehicles you should then look at the latest safety items and add them to your kit.

• A recovery link for joining straps
• Recovery safety lanyards
• A recovery bridle
• A recovery safety blanket

A strap from a reputable manufacturer should have a label stitched in, detailing compliance to SANS 94 and full technical details of the product, its specs and application.

Remember to assess the situation, if time is against you, say in the case of an incoming tide it’s best to either attempt to winch a stuck vehicle out before resorting to a kinetic strap or rope. However careful planning and safe utilisation of the basic equipment will more than likely be all that is required.

In closing, using an unlabeled strap or rope is dangerous and you put yourself, vehicles and others at risk. Go out and enjoy the great outdoors but be safe and responsible. Not only in a recovery situation but with everything that you do! Remember all SecureTech straps have a free lifetime repair warranty

For further information contact, michael@liftlash.co.za

About the Author

Glyn Demmer

My first 4x4 was a Nissan Hardbody thereafter I started travelling all over the country. In 1992 we held a big 4x4 day with hundreds of Nissan families, and then the 4x4 bug really bit. A friend Monty Brett and I started running 4x4 courses at the Hennops Off-road Trail just outside of Johannesburg. At first we offered day-and-a-half courses that started on Friday afternoon and finished on Saturday afternoon. Hannes Grobler the Rally Ace regularly assisted, and we reached a nice balance between our two styles and our skills.

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