Natural anchors
Natural anchors are anything that you find suitable to attach a cable to - trees, rocks and signposts (signposts on gravel roads are unreliable and pull out of the ground very easily) If you are going to use a tree as an anchor, protect the tree by using a tree-strap to prevent the steel cable from cutting into the bark as this can kill a healthy tree. Attach the strap as close to the ground as possible.
The strength of an anchor depends on how badly the vehicle is bogged and how much preparation is made before winching begins. Assess the strength of the anchor first - if it appears weak, then pre-preparation to the vehicle will need to be extensive. If the anchor is fool-proof, little or no preparation may be needed, and if winching fails nothing is lost and some digging and clearing can be done.
Have someone monitor the condition of an anchor during recovery. If it appears to be loosened by the winching, then halt the process before it is weakened further because even a weak anchor is better than no anchor at all. To put less stress on the anchor more clearing around the wheels and jacking must be done before further winching.
Man-made anchors
If there is no anchor to which a winch cable can be attached, a man-made anchor can be created. No made-made anchor of any reliability can be made without a lot of effort. Consider the alternatives - what is the effort and time likely to amount to, to create an anchor, dig a bit and then use the winch; or, dig a lot and maybe use a jack and then drive out. In very difficult situations all of these will be required.
Anchor construction tools:
· Heavy hammer
· Iron standard/s or purpose designed stakes
· Danforth boat anchor/Pull-Pal anchor
· Chain, shackles and anchor strap
If the vehicle is bogged down where there are no good anchor points, an anchor can be created.
Here’s how:
· Drive steel stakes into the ground at 45° and about one metre apart and then attach the cable to the stakes as close to the ground as possible. Create ‘Vs’ between the top and bottom of each stake. See photograph on page 194.
· Danforth-type boat anchors also work well if the ground is soft. This is because the harder the pull, the deeper they drive into the mud - in theory. The angle of pull must be as close to the ground as possible. Pull-Pal from Orvas (011 646 9708) is an effective anchor in soft ground. Both the Danforth and Pull-Pal are bulky and overly heavy for expedition use.
· A long length of chain run along the ground secured with ten or more long tent pegs. The more difficult the winching operation, the more tent pegs will be required. This man-made anchor takes little effort and if the vehicle is not deeply bogged it is a quick and effective way of creating a light-duty anchor.
· As a last resort a spare wheel can be buried either horizontally or vertically which is the more conventional but less effective way. The winch cable is passed through the middle of the wheel and attached to a steel bar (use a power bar or a heavy wheel spanner). After burying the spare wheel, dig out from under the vehicle making sure that no soil is supporting the vehicle’s weight. This is a last resort because burying the wheel is hard work and despite perserverance it is often a waste of time.
Remember: the harder the effort put into an anchor, the better its effectiveness. Before using your man-made anchor - which under most conditions will be suitable only for a light-weight pull - dig out channels in front of all four wheels to allow easier forward movement. Do not be in too much of a hurry when preparing the anchor or digging out soil from under the vehicle. If you try to winch before you are absolutely ready, you may fail - and have to go through the entire process again. Once you are ready to begin winching, aid the process by having everyone not directly involved with the winching pushing the vehicle. Engage low range second and apply as little throttle as possible. Do not permit the wheels to spin.
Winching in deep cloying mud
Mud can sometimes be the most difficult stuff. When it is particularly thick it creates a vacuum under a vehicle and no matter how much winching and heaving, the vehicle just won’t move. When this occurs the vehicle’s progress is halted as much by the lack of traction as by the vacuum. Here a combination of high-lift jack and winch is required.
This is the way to go about it:
Place the jack about a metre in front of the bogged vehicle and lift up the jacking step to shoulder height. Run the winch cable over the jacking step to the anchor. Tilt the jack away from the vehicle and take up the tension. Now, with someone supporting the jack, begin winching in. As the cable is retrieved the jack is pulled upright, simultaneously pulling the vehicle forward and up, releasing the vacuum. Repeat this as many times as required.
The use of hub capstan winches
These simple devices allow the spinning wheels of a bogged vehicle to act as a winch. Hub capstans are attached directly to the wheel rim and a rope or cable is guided through a groove in the steel and secured with a knot or buckle. The rope should then be wound around the capstan at least five times, crossing over itself. The direction of wind and the gear selected (forward or reverse) will determine the direction of pull. Hub capstans on both wheels on the same axle must be used simultaneously as the axle differential will not allow winching on a single hub. Because rear half-shafts and differentials are generally stronger than those in front, it is recommended that the rear wheels are used for pulling. The vehicle must be engaged in four-wheel drive, hubs must be engaged and for those operating permanent four-wheel drive vehicles, the centre differential must be locked. Using hub capstans can damage the vehicle if the cables are allowed to get too short when the wheels are pulled together by the narrowing angles between the two lines.
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