Friday, 9 December 2011


The Petzl Shunt is arguably one of the best solo fall-arrest devices on the market,if you can figure out how to rig it properly that is!?
It can be a confusing piece of kit as it was originally designed as a kind of prusik-brake for abseiling(something its not very good at!).Then it was touted as a fall-arrest device(many IRATA instructors still swear by it),and allso as a mechanical-prusik for rope ascents.

The Petzl Shunt.

 Its no small wonder therefore that climbers either love it,or hate it! I fall into the former category.
If you Google up "roped soloing" you will find loads of climbers on Youtube using it in strange and mysterious ways to climb fixed-rope routes on crags all over the planet.Allso if you Google up "Shunt Fall-Tests" you will likewise find some great corporate videos of it being tested to destruction.There are lots of these so i wont bother linking any.But its a great idea to check them out if you realy want to know how tough the Shunt realy is!?
Getting it to run hands-free for solo-mountaineering is not easy,but once understood it gives you a simple,versatile device for self-belay on both "Single and Double" rope systems.No other device available on the climbers market today does this!

Picture (1)-Solo Rope Drag.

I chose to present this technique using the "Solo Rope Drag" (as against carrying the ropes) and incorporating a shoulder-harness configuration to show its dynamics and versatility to best effect.It can be far more simply used with a bungee neck-sling or a "Baudrier" chest harness setup on a single-rope or rope-loop system.I hope that the pics will help you formulate your own innovations in using this device solo,and hands-free.
Like all the other self-belay inovations i present in these blogs,the Shunt has a smooth friction-cam,rather than teeth that can cause damage to a rope in a fall.The most damage you will incur to your rope in a factor-2 on Shunt is a little welding or scorching to the mantle on one side! The Shunt is unique in that it allso takes Double as well as Single rope systems from 8mm to 11mm diameter.
You can allso feed the Shunt from a sack or shoulder-slung rope bag,or have the climbing rope trailing over the shoulder to the ground or hanging as in "Big wall aid-climbing",should you wish to climb without an encumbering rope-coil on your body.
Picture(1)-Shows double ropes trailing in Solo Rope Drag fashion on an Alpine style ascent.I am not a big fan of this due to potential snagging or rope damage,but it is a good workable technique to cut down body weight on long alpine soloes.

Rope-Drag body rig(Right side).
(Thats not my belly!Its Paramo-Torres.)

Note that the trailing ropes run through Krabs on the back of the harness to minimise leg tangles.

Pic(2)-Full chest rig.

Picture(2)-Shows the full chest rig.The secret to keeping the Shunt running freely,is to mount it on a fixed plastic backing plate that tilts the tongue of the device away from the chest by about 2-inches(any closer and it will lock onto the ropes or cause tiresome friction drag on the climber).When i first figured this out i used a "Costa-Coffee" cup lid with a hole punched through it to get the right angle!(see pic).Ive since made a great workable locking-plate out of tough plastic pipe and will put it up in a later blog!Note the rope-ends clove-hitched to a harness belay-krab!?

Starfish Anchor system.
(My new design-More on this later!)

This keeps both ropes in perfect position to instantly attach to a Starfish Multi-directional Anchor system.One can use fast "Locked Clove Hitches" for this which is far less time consuming and complicated that Figure-8s,and they are equally secure.(If you cant find them in the Knot-Books?Gimme an email!)

Learn the "One handed Clove Hitch",and practice!

The Clove Hitch is the "most" useful knot in climbing,and every climber should be able to do them in their sleep! It takes very little time to learn and leaves you with your other three limbs as "three points of contact" for maximum balance and safety!

Clipping protection.

Picture(3)-Shows clipping protection on ascent after anchor has been placed,and is exactly the same as for the Troll-Rocker(see blog archive).I am happy to clarify points of detail or answer sensible questions on this rig.Feel free to comment(like a human being that is?!) or email,or even phone if your good looking? But right now i need a large Cognac and my feet up on the cat for a few minutes! :-)

Good climbing,



  1. Hi Rob. I use a Rocker as per your other blog for ascending, work positioning (with a 5m lanyard) and back-up. I see in details of the rocker that it can be used as a belay brake. Do you know if this means it can be used as a descent device as well? Any info much appreciated!
    Cheers, Pedroski

  2. Rob, I didn't realised you were so local to me!

  3. I have not used it as a descent device.But see no reason why it cannot be used to descend a rope in tandem with a Prusik or Bachman.If you live local drop me an email,allways happy to talk technique.Best,Rob


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