DRIVING/TOWING - RECOVERY TECHNIQUES
A hand winch can be used for vehicle recovery from virtually any stranding and using the right technique can reduce the required physical effort.
“Give me a firm place to stand and I will move the Earth,” said Archimedes after fiddling around with some levers. The sweat he must have worked up led him to a cool bath and his most famous pronunciation: “Eureka!”
Nothing’s changed since 270BC: if you operate a lever for long enough you’ll need a bath.
Hand winches are like bicycles in that respect: independent of fuel other than muscle power, but tiring for the uninitiated to operate. Nonetheless, a hand winch is a very useful backup to a power winch and essential kit for solo-vehicle, off the beaten track travellers.
The most popular hand winches are similar in design and employ Archimedes’ leverage principles, in conjunction with some clever wire rope work. A lever provides the horsepower and direction, while cams and jaws provide a friction grip on the wire cable that runs through the winch housing.
Most hand winches feature two levers and two sets of jaws. When pulling, the front jaws clamp on the cable and the forward lever action drags a few centimetres of cable inside the winch. As the lever is moved backward for the next stroke the rear jaws lock onto the cable, freeing the front jaws for another grip. The action is like using your hands in sequence to pull in a rope. When winching out, the rear lever is used and the jaw sequence is reversed, so the cable direction is also reversed. Jaw action is controlled by a safety catch that prevents a loaded cable being accidentally unclamped.
Hand winches vary in size from 800kg to 3.2 tonnes capacity, but the most popular size for vehicle recovery is 1.6-tonnes line-pull capacity. This is light-on for hauling loaded wagons up steep slopes, but a hand winch is almost always used in conjunction with a snatch block that provides a theoretical 2:1 mechanical advantage, thus doubling capacity to around three tonnes.
A 1.6 tonnes capacity hand winch and telescopic handle weighs 13-16kg, plus the 13kg weight of 20 metres of wire cable, and measures about a half-metre in length, so stowage isn’t a major problem. The 3.2 tonnes capacity models are half as long again and weigh twice as much.
Manufacturers’ literature is full of images of happy people hauling and dragging heavy objects, but real life is seldom like that. We evaluated three hand winches to see how much fun we could have dragging a loaded ute up a metre-high, 45-degree-slope rock shelf.
The single-line-pull test
For this exercise we used a couple of hand winches: Tirfor’s T516D and Mean Green’s RGHW16. The Tirfor was rated at 1.6 tonnes line pull, but the Mean Green claimed 1.6 tonnes capacity for lifting and 2.5 tonnes capacity for winching.
We tossed around several ideas for measuring the operator effort needed to work these winches, but settled on the good old ‘puff factor’ as the most realistic assessment method.
We tried each one twice and in different order, so fatigue wouldn’t cloud our judgement. Noye that this test was done using only a single line – no snatch block.
The ute was positioned in exactly the same spot for each winching exercise and we used the same snatch block and tree sling for all attempts.
There is a theory that attaching the winch to the vehicle gives better control, but we don’t agree with that. If you’re hand winching the safest point is near the anchor point, not in a position that means you have to move with the vehicle. Archimedes suggested firm ground on which to stand and we
agree with him.
Our very fit tester couldn’t detect any lever load difference when working the Tirfor and the Mean Green. Both winches hauled the big ute up over the shelf, but considerable effort was necessary. The average off-roader would have spent an estimated 15 minutes – including rest stops – to get the 2.5-tonnes-weight vehicle up this shelf.
It was obvious as the sweat trickled and the water bottle drained that single-line hand winching isn’t a job for the faint-hearted.
The high-lift jack as a hand winch
High-lift jacks are less popular than they used to be; mainly because many modern 4WDs aren’t high-lift-jack compatible.
However, some travellers – ourselves included – still find them very useful, because as well as being excellent vehicle lifters high-lifts can be vehicle pullers.
The effort needed is greater than with a proper hand winch, even with a snatch block between the anchor point and the front of the vehicle.
To rig up a high-lift as an emergency hand winch you need a length of chain fitted with a fixed hook on one end and a grab-hook on the other. You shackle the chain to the vehicle and to lifting lug on the high-lift jack and shackle a winch extension strap to the top end of the rack.
Then as you work the lifting lever back and forth the lifting lug will travel along the rack, pulling the vehicle with it. When the lug has travelled the full length of the rack you have to chock the vehicle, run the lug back to the bottom of the rack, shorten the chain, using the grab hook and start again. It’s slow, but it works.
If you want to use a snatch block you’ll need synthetic winch cable instead of a winch extension strap, unless you can find a snatch block that’s compatible with webbing material.
The snatch block winch test
For this test we used a Mean Green hand winch (kindly supplied by Opposite Lock) and the same 2.5-tonne ute load. In place of a rock shelf we blocked the front wheels with a log on one side and a large rock on the other.
Everyone knows that a snatch block virtually halves the work load on a winch – plus some frictional losses – but not so well known is that hand winch wire isn’t compatible with the commonly used , small-diameter snatch blocks. thick, hand-winch wire doesn’t like to bend around pulleys.
Our solution is to employ a length of synthetic winch cable that is much more pliable than any wire cable and hook that to the hand winch wire cable. The hand winch cable does a striaght pull, as it’s designed to do, while the synthetic cable runs through the snatch block.
For this test we rigged up the hand winch in accordance with the accompanying sketch and found that the effort needed was comparatively light.
Any reasonably active person could work the winch handle and, while the operation took twice as long to move the vehicle the same distance, the winching person could keep at the job for three times as long.
For extreme hand-winching work we’d introduce a second snatch block into the linkage. Check out our video of the test: