Goto Chockstone Home

  Guide
  Gallery
  Tech Tips
  Articles
  Reviews
  Dictionary
  Links
  Forum
  Search
  About

      Sponsored By
      ROCK
   HARDWARE

  Shop
Chockstone Photography
Australian Landscape Photography by Michael Boniwell
Australian Landscape Prints





Chockstone Forum - Gear Lust / Lost & Found

Rave About Your Rack Please do not post retail SPAM.

Topic Date User
Solo Top Rope with Mini-Traxion. 26-Aug-2007 At 10:55:10 PM JBM
Message
I'd like to rekindle this debate.

I recently became acquainted with a shunt as an abseil backup during some alpine climbing and have begun using it to self belay on top rope on projects that are still a couple grades beyond me.

Clipping the shunt directly to my belay loop on a 10mm rope seems to work a treat. I weight the bottom of the rope about 1m of the ground to take into account rope stretch and the shunt slides smoothly up the rope with no dramas. I took about 20 "slumps" onto the device today with no obvious rope damage (caused by the shunt, at least) and I lowered off easily with prussic and abseil device.

Is there a better a self belay system out there? If so, I'd like to know about it. Has something better been developed since this debate in 2005?

As an aside: I understand that Dave Macleod used a shunt to work the moves on his E11 Rhapsody.

Let's hear it.

On 22/06/2005 The good Dr wrote:
>There seems to be at times a misunderstanding of what various devices actually
>do, and how they operate.
>
>In terms of the shunt the device is designed to absorb energy by sliding
>a small way down the rope when shock loaded. Some informal tests have been
>conducted on the shunt and other devices (eg ascenders) in terms of their
>shock load absorbtion capabilities. Ascenders do tear sheaths and will
>sever ropes due to the aggressive teath. The shunt does not. One particular
>area where a shunt will fail is if during the slide (up to 60cm) it encounters
>a knot. This transfers the energy back into the casing and may cause it
>to fail. Read the technical information from Petzl to get a clear picture
>of the shunts capabilities. Each of the ascender manufacturers also have
>technical information and they usually say that the device is not to be
>used as a fall arrest device (I have yet to see an ascender which states
>that it conforms to the Australina Standards as a fall arrest device).
>
>The following is also incorrect.
>
>>Even at best industrial shock absorbers are designed to minimise the
>chance
>>of death in a fall, not act like a dynamic rope, ie soften the fall,
>the
>>amount of force needed to deploy one is enough to make you one sick puppy
>>for awhile!
>
>The forces generated in a fall are greater than you think and the body
>absorbs quite large amounts of energy. An industrial shock absorbing lanyard
>is designed to reduce the force transmitted to the body to a maximum of
>6kN. They are designed for a maximum free fall of 5.75m. Smaller falls
>will give partial deployment of the shock absorber. The initial limit of
>deployment for the shock absorber is up to the manufacturer but must still
>be within the scope of the Australian Standards (AS/NZS 1891.1). In combination
>with a fall arrest harness that is correctly fitted the forces transmitted
>to the body are not excessive, though if you do take the full 5.75m fall
>you are sure to have one or two tender spots.
>
>Heresay is not great when it comes to equipment, as each has its design
>purpose and usage restrictions. A lot of industrial equipment failure is
>caused by incorrect usage, not poor design.

There are 40 replies to this topic.

 

Home | Guide | Gallery | Tech Tips | Articles | Reviews | Dictionary | Forum | Links | About | Search
Chockstone Photography | Landscape Photography Australia | Australian Landscape Photography | Landscape Photos Australia

Please read the full disclaimer before using any information contained on these pages.



Australian Panoramic | Australian Coast | Australian Mountains | Australian Countryside | Australian Waterfalls | Australian Lakes | Australian Cities | Australian Macro | Australian Wildlife
Landscape Photo | Landscape Photography | Landscape Photography Australia | Fine Art Photography | Wilderness Photography | Nature Photo | Australian Landscape Photo | Stock Photography Australia | Landscape Photos | Panoramic Photos | Panoramic Photography Australia | Australian Landscape Photography | High Country Mountain Huts | Mothers Day Gifts | Gifts for Mothers Day | Mothers Day Gift Ideas | Ideas for Mothers Day | Wedding Gift Ideas | Christmas Gift Ideas | Fathers Day Gifts | Gifts for Fathers Day | Fathers Day Gift Ideas | Ideas for Fathers Day | Landscape Prints | Landscape Poster | Limited Edition Prints | Panoramic Photo | Buy Posters | Poster Prints