When a link needs to be made between elements in the recovery operation, in most cases a shackle is the most suitable and reliable way to do it. Using the incorrect type of shackle can result in damage to the strap or a failure under stress. When selecting shackles for your recovery tackle don’t be tempted to go the cheap route. There are some Chinese shackles which are a direct copy of some excellent English products but are not as strong.
Working load markings
Quality shackles are marked with indelible information such as the safe working load, the maker’s name and sometimes 45° marks. If there are no markings on the shackle it is probably inferior and cannot be trusted. The safe working load is the important bit of information. Decent sized bow-shackles are 4 3/4 tons. This means that the shackle’s breaking load is 5,4 times that much. In the case of a 4 3/4 ton shackle the breaking load is 25,65 tons.
Important rules when using shackles:
· When using a shackle for recovery operations, tighten the bolt and then loosen it by a quarter of a turn. This prevents damage to the thread and makes releasing the bolt easier.
· When using a shackle for a long-distance tow, hand-tighten the shackle bolt firmly.
· Good quality shackles rarely fail - they simply distort so that they are difficult to undo. It is normally the chain or tuggum that fails first.
· Shackles designed to snap closed are unsuitable for vehicle recovery as they are not strong enough and can fail even in light duty operations.
· NEVER use two shackles to join two tuggum straps together. If one strap should break the attached shackles become a deadly missile. Joining two tuggums together is illustrated later in this chapter.
D-shackles are used in the following ways:
· Joining sections of chain or attaching a chain to a vehicle.
· Attaching a snatch block to a vehicle.
· Attaching a chain to anchor/tree strap bow-shackle.
Bow-shackles are used whenever straps need to be connected. The extra width of a bow-shackle prevents the strap from being crushed during maximum stress.
Bow-shackles are used in the following ways:
· Attaching tuggum straps to chains and anchor straps.
· Attaching snatch-blocks to tree straps.
· Attaching tuggum-straps to vehicles.
Always place the strap over the bow section and the chain or snatch block over the bolt.
Towing rings and eyes
Off-road vehicles should have towing eyes at both front and rear for use during vehicle recovery operations. Do not attach towing lines to a bush bar or to any part of the vehicle body or steering mechanism. If there are no towing eyes, attach lines to suspension components such as spring shackles, but beware of sharp edges damaging the rope or cable.
Snatch blocks
A snatch block is a hook or eye attached to a large pulley wheel through which the winch cable runs. A snatch block effectively gears down the pulling power - it doubles the pulling force at half the speed and is used in conditions where the winch power is insufficient for the task.
The following uses and advantaged are associated with using snatch blocks:
· Doubles pulling power.
· Winching from difficult angles.
· Overheating of electric winches reduced.
· Current draw is reduced and are therefore kinder to batteries.
Rings and eyes
All off-road vehicles should be fitted with numerous easily accessible towing eyes for vehicle recovery and winching. Factory fitted towing eyes are suitable for light and medium duty towing operations. They are not designed for use with tuggum straps. Therefore when a tuggum strap is used, both towing eyes must be used. This is illustrated in a later chapter on vehicle recovery. The correct alternative is to fit heavy-duty towing attachments.
Familiarise yourself with the location of your vehicle’s towing eyes before venturing off-road. When a vehicle is stuck in deep mud, it can be difficult to reach towing eyes that are located far beneath the vehicle or low to the ground.
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