4 x 4 Australia - - Techniques -

THE need for mul­ti­ple line pulls should be ap­par­ent, but the ac­tual me­chan­ics of it are rather im­pres­sive. In­stead of hook­ing your winch line di­rectly to the tree trunk pro­tec­tor, as you would in a nor­mal re­cov­ery, you run the line out through a pul­ley block at­tached to the tree trunk pro­tec­tor and then back to your four-wheel drive’s re­cov­ery point with a damper over both lines. This halves re­cov­ery speed and dou­bles the pulling power of the winch, giv­ing a 12,000lb winch 24,000lb of pulling force – that’s close to 11 met­ric tonnes.

Next, add an ad­di­tional pul­ley block to the ve­hi­cle’s re­cov­ery point, run the winch line to a sec­ond tree with a tree trunk pro­tec­tor, and add an­other winch damper, to triple the pulling power of the winch.

This pro­vides a pulling force of

36,000lb, al­though it will also cut the speed of the re­cov­ery by one third.

It’s im­por­tant to note a winch’s pulling power is rated with just one layer of rope on the drum. It loses roughly 12 per cent pulling power for each ad­di­tional layer of rope on the drum. Per­form­ing a dou­ble, or even triple, line pull can help get more rope off the drum and give you more chance of get­ting free.

By run­ning the winch line back to the ve­hi­cle through a pul­ley block, we’re halv­ing the ef­fec­tive speed of the winch and dou­bling its pulling power.

Due to the en­ergy stored in the rope and ca­ble, a damper (or winch blan­ket) is re­quired for each in­di­vid­ual line. Heavy cloth­ing or car seat cov­ers can work in a pinch.

Pul­ley blocks don’t re­quire a 180-de­gree turn and can be used to winch around cor­ners, or even to re­cover a ve­hi­cle be­hind you if you’re un­able to turn around.

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