An Introduction to Jiggers

Written By: Lance Piatt

The following information is meant only as an informational introduction to the loveable jigger system.

An Introduction to Jiggers

Generally, these beauties are considered pre-rigged pulley systems used mainly for hauling, but can be very important in lowering heavy loads as well. The advantage of these systems is in their rapid deployment, and straightforward operation without advanced levels of training or expertise. They are low maintenance and high yield work horses and have been around for many a year.

Rock Exotica AZTEK Elite Kit

The AZTEK system is used in rigging programs around the world. These, configured as “set-of-fours” (double blocks) will enable the rescue practitioner greater versatility in a personal mechanical advantage (PMA) for rescue and general rigging. The swivel Omni pulleys (blocks) are hewn from a solid block of high strength aluminum and are engineered with great pride to withstand over 8,000 lbs (36kN) of tensile force end to end.

From old (and new) time mariners, to arborists, to rescuers, to the backyard working guy (or gal), jiggers have much to offer. An obvious application in industrial height safety, is lifting the weight of a fallen worker so that he can be transferred to a lowering rope. Arborists use many a jigger (fiddle blocks) for raising and pre-tensioning heavy loads. General riggers can apply these gems in hundreds of other manners (from pulling to maintaining).

Most of the time, double pulleys are teamed together to form a 4:1 mechanical advantage (depending on the line of pull, a 5:1 can also be accomplished). Efficiency is determined by the friction — or lack thereof — in the system (more on this in future newsletters).

There is another very important factor to consider. All rescue pulley systems (and for that matter most non working pulley systems) must have a system which allows the rope to be pulled in while not allowing it to be released. This is called a progress capture or clutch system. Either prusiks or camming units can be applied. Your capture device will vary with circumstances and system, so choose wisely, because all systems are not created equal.

Petzl Jag Rescue Kit

Ready-to-use reversible rescue kit designed to easily pick off and lower a victim. It contains a JAG SYSTEM haul kit, a RING OPEN gated ring, an I’D S descender, a CONNEXION FIXE 150 cm anchor strap, a BUCKET bag and an AXIS 11 mm rope with two sewn terminations. Available in three lengths: 30, 60 and 120 m. Hauling with the JAG SYSTEM haul kit whose 4:1 mechanical advantage and excellent sheave efficiency allow the user effort to be divided by four when raising a victim in order to release him. Evacuation with the I’D S descender, whose ergonomic handle allows the user to easily control the rope’s running speed during evacuation.

Peace on your days!



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