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Equipment Notes

Introducing an occasional series of articles discussing various items of new equipment currently appearing on the caving market…

By ‘ Cam’

There is still silence from Jumar’s to give a date when we may expect their ascenders to re-appear. They are produced to what amounts a ‘cottage industry’, but last year were forced to re-build a large proportion of their ageing equipment.  While they were doing this it was proposed that they would do a re-design to produce a ‘super-Jumar’.  Last information was, however, that they were having second thoughts on the lines ‘we have a good product – why change it?’

They may have to think yet again with the introduction in this country of the American CMI (Colorado Mountain Industries) 5000 Ascender.  This is very much Jumar shape, but has an extruded and. machined, rather than a cast body.  There are double anchor points at the bottom for karabiner attachment, the safety catch is designed for ease of use wearing gloves and is hard wearing, impregnated nylon material.  The cam safety catch and return spring is removable for cleaning or replacement. Points of criticism seem to be the lack or a moulded handle, and the circlip fixing of the cam pin which seems a little flimsy.  They should retail cheaper in caving shops than climbing shops, but are around £30.00 a pair at the time of writing (March 1979).

Also now arriving in quantity from U.S.A. are spring-loaded Gibbs Rope walkers.  The standard Gibbs has been discontinued and they are now all fitted with quick release pins.  The old model (QR) is now the standard, and the sprung model is the same but with the body punched to form a lip on which the body is held back.  Both models can surprisingly be purchased at the same price, about £10 each.

Clam products of Littletown, Yorkshire, are preparing to market an ascender-descender system based on wire rather than ropes.  Details will remain secret until their patent comes through!

Another patented device soon to enter the scene is the Lewis descender.  This is a self braking device, with a ‘dead-man’s’ handle built onto the side.  It can be used on a single or double ropes, but is similarly to a certain well known Mendip ‘Buggery Box’ leads one to think that perhaps Glyn Bolt, of Goldlock fame may have one or two words to say about this patent!  The breaking bar itself is also reminiscent of the Petzl shunt.

Petzl are also said to be experimenting with a self-braker, but no details are known.  Bridon’s Kevlar cored ‘Viking Super Speleo’ rope is now commercially available.  The theory is that the Kelvar fibre, which is very strong and has negligible stretch, will provide a rigid SRT rope, but in the event of a fall it will break and the shock absorbed by the double nylon outer sheaths.  However, the core is said to have the strength of 1000kg, which will give the person on the end of the rope a nasty jolt!  That, together with the very dubious flexing quality of ‘Kelvar’ makes one hope that Andy Eaves, who helped design the rope really does know more bout it than most.  Cost, about £24 per hundred feet.  A thought worth bearing in mind is that a manufacturer of rope using nylon to construct a drive belt for a machine.  The nylon lasted (on average) 1000 hours.  They thought Kelvar would solve their problems, but a belt of this material lasted only three minutes!