Shunt vs Grigri

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Pros and cons of each for self protected top roping (shunting)? 

I know petzl don't recommend either. I have used a shunt previously. The transition from climbing to abseiling appears less bother using a gri gri. What am I missing? Does the rope run OK through gregory when climbing? 

 Offwidth 09 Jul 2019
In reply to Presley Whippet:

I know plenty of people who've used a shunt on its own (Petzl recommend a backup as well). I've never heard a grigri can be safely used on its own in that way.

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 jimtitt 09 Jul 2019
In reply to Presley Whippet:

I sometimes use a Grigri alone but normally a Shunt on one strand as the primary and a trailing Grigri on the other for getting back down. The Grigri doesn't run as well until maybe 10m up or needs more weight. Mine's modified as well, with a standard one it's fairly rubbish.

 wbo 09 Jul 2019
In reply to Presley Whippet:. Basically the answer is no, it doesn't run so easily through the GriGri.  You'll have to manually pull it through

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 agent_smith 10 Jul 2019
In reply to Presley Whippet:

There's a few issues to consider... this topic has been done to death in many forums and there is no singular magic bullet answer.

Some assumptions here...
1. that you are climbing alone - (rope solo) - no one else around
2. that you are a recreational climber (not 'industrial' rope access - purely for adventure + fun)
3. that when you say 'top roping' - it is assumed that you have setup a fixed rope that is securely anchored at the top of the cliff/route and fully extends to the ground or to the base of the route.
4. that you are using a single (ie one) fixed rope - not two (2) fixed ropes (like rope access).

You can muck about with all sorts of devices and/or try to use devices/systems in a way that violates the product user instructions.... or
You could just spend a few bucks and purchase a proper 'guided type fall-arrest device' that conforms to an appropriate standard - eg EN 353-2 / EN 12841

One such 'guided' type device that shouldn't break your bank  balance is the ISC 'Rocker'
Link: https://www.iscwales.com/Products/Showcase/RP500-Rocker-Ropegrab/0/

The 'Rocker' will automatically travel up and down a fixed rope 'hands-free'.
However, it isn't an abseil descending device - so you would need to change-over if you wished to abseil.

Of interest, IRATA (a British rope access organisation) no longer recommends the Petzl Shunt as a backup fall-arrest device. And neither does Petzl. That should set the alarm bells ringing in your head.
An issue that is a threat to your safety is the instinctive reaction to 'panic grab' the device when you fall. If you 'panic grab' a Shunt, you will ride with it to the ground and go SPLAT. Rope access dudes have long understood this risk - and they install a 'rats tail' short towing string to the Shunt. The theory being that if you are towing the device by the string, and you suddenly fall - a panic grab reflex should save you because you cant grab hold of the string properly. But, this is not foolproof - and so IRATA and Petzl have finally come to their senses and no longer recommend the Shunt as a fall-arrest device.
A Petzl GriGri doesn't travel up a rope hands-free - so this is obviously a major draw-back (you have to continuously draw the rope through the device - which can be strenuous/fatiguing).

With the ISC Rocker, if you get tired - you can just stop and sit back and the Rocker will hold you in position. While hanging, it is relatively simple to change-over to a descent system. You don't need a 4 year degree from a university to change-over to abseil descent while hanging from a 'Rocker'.
You would need to carry an abseil descent device (unless you just want to descend on a Munter / Italian hitch (#206).

I've also seen a few climbers use a Petzl 'ASAP' for this type of 'rope solo' fixed rope climbing. The ASAP is the ultimate hands-free device but it is expensive. However, the ASAP wont immediately lock if you just sit back and try to rest - it works rather like a seat belt in a car. Rope access guys who also climb recreationally have used it for rope solo (fixed rope) climbing... They already own it as their prime backup fall-arrest device.

The ISC Rocker can be obtained fairly cheaply - and it is fit for its intended purpose.
And these are the key words... "Fit for its intended purpose".

Post edited at 10:47
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 MischaHY 10 Jul 2019
In reply to Presley Whippet:

Just use a shunt extended from the belay loop to a chest harness with a quickdraw dogbone. This makes a fall minimally dynamic and means the device feeds better. Use a decently fat single strand and tie backup knots below you (overhand on a bite or similar) so that if the device didn't grab you'd just ride it down to the knot where it would block. If you're worried about the carabiner failing you can trail a maillon below the shunt on a short length of rope which will not interfere with the device but will act as a rope block in the event of the shunt somehow failing. 

I happily used this system for a few years without issues when I was climbing in the UK and never once had the shunt slip. 

 TobyA 10 Jul 2019
In reply to agent_smith:

It's funny (peculiar) how much this changed over the years. When I first bought a shunt in the mid 90s I'm pretty certain the box had instructions on how to use it for self belaying on a top rope, and I get the impression that Dave Macleod for example has prepared for most of his big routes by shunting routes!

I haven't used mine for self belaying for years, but I guess I won't ever again if Petzl now say don't.

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 danm 10 Jul 2019
In reply to TobyA:

The other problem with the Shunt is it has a fairly weak folded metal construction, held together with a small reinforcement tab. If it hits a knot in the rope at speed, it will generally explode open and detach from the rope. It is very kind to the rope though!

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 Phil79 10 Jul 2019
In reply to agent_smith:

That ISC Rocker looks like a good bit of kit - do you have one and have you tried it in practice? 

In many respects I like the Shunt, easy to use and moves up and down rope well, but also worry about the 'panic grab'. Also mine sometimes makes a slight creaking noise when loaded, which doesn't inspire confidence!

 Iamgregp 10 Jul 2019
In reply to Presley Whippet:

Has anyone used a mini traxion for top rope soloing?  I know you'd have to use something else to come back down once you're up, but it sounds less faff when you're actually climbing?

 Coel Hellier 10 Jul 2019
In reply to Iamgregp:

> Has anyone used a mini traxion for top rope soloing?

I've used a micro-traxion, and it's fine. 

 Iamgregp 10 Jul 2019
In reply to Coel Hellier:

good to hear, looks like a good little device to me...

In reply to Presley Whippet:

Have you seen the instructions that Petzl recommend?

https://www.petzl.com/US/en/Sport/Installation-on-one-single-rope-with-two-...

They don’t recommend using a shunt:

https://www.petzl.com/US/en/Sport/Appendix-1--Petzl-dœs-not-recommend...

As danm said “The other problem with the Shunt is it has a fairly weak folded metal construction, held together with a small reinforcement tab. If it hits a knot in the rope at speed, it will generally explode open and detach from the rope. It is very kind to the rope though!” If you got to Outside in Hathersage they have a couple of shunts that failed in such circumstances!

Post edited at 16:35
 pec 10 Jul 2019
In reply to agent_smith:

> You can muck about with all sorts of devices and/or try to use devices/systems in a way that violates the product user instructions.... or

> You could just spend a few bucks and purchase a proper 'guided type fall-arrest device' that conforms to an appropriate standard - eg EN 353-2 / EN 12841

> One such 'guided' type device that shouldn't break your bank  balance is the ISC 'Rocker'

Earlier this year I was looking at buying a fall arest device for top rope soloing and came accross the Rocker which initially seemed ideal but whilst researching found some examples of failure with it. As an example the following thread mentions a few failures from posters on this caving forum, who probably rely on such devices more than climbers.

https://ukcaving.com/board/index.php?topic=19405.0

Its a bit sobering to find that the "ideal" device can still fail with serious consequences. My take is that there is no such thing as a totally reliable device but that the shunt which has been widely used by climbers for many years, if used with knowledge of its likely failure mode but backed up with a reserve device may well be as safe as anything. But who knows?

Post edited at 20:57
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In reply to Presley Whippet:

Had a play with the shunt tonight, worked fine. Previously, 90s, I had used it on a doubled rope, which was a faff switching to abseil. This time I used a doubled rope, 1 strand for shunt, other for abseil. Much easier. 

Could use 2nd strand to back up with gregory, a knot, other device or even a 2nd shunt I guess. 

I didn't try gregory as I couldn't see how the rope would pass through smoothly. 

Thanks all. 

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 simondgee 10 Jul 2019
In reply to pec:

My preference is redundancy and having 2 ropes (1 rope halved) and independently tied off in the middle at the belay to give 2 strands ...then  chest croll on 1 side and a gri gri on the other rope. the croll moves effortlessly the gri moves without intervention but is a bit more sluggish. I weight each strand with half my rack. Abbing back down is obviously easy being already pre rigged. Any 'falls' are slumps onto the rope so the toothed croll isn't really an issue. I don't bother with backup knots given the redundancy.

 RR 10 Jul 2019
In reply to agent_smith and all:

The Petzl Microcender takes rope diameters from 9 millimetre and up (what is more or less today’s standard.)

The ICS starts at 10,5 millimetre and up what is quite thick. Is it just like with the Silent Partner that a smaller rope runs better/easier, but is not recommended? I should like to know. Very interested as an alternative for the Shunt.

With the Shunt I train a lot. Works fine on a normal 9,8 Mammut rope. Use a double rope from the top. Only if I am just above a bolt and if I fall the lever of the Shunt will hit the bolt and release the Shunt (I can imagine in theory). Never tried it.

Sometimes I use, on for me challenging rock with lot of rests etc, a Micro traxion and a Mini traxion with a semi static rope. The sound of the traxions is reassuring. Lot of doing though. 

 agent_smith 10 Jul 2019
In reply to pec:

> Earlier this year I was looking at buying a fall arrest device for top rope soloing and came accross the Rocker which initially seemed ideal but whilst researching found some examples of failure with it. As an example the following thread mentions a few failures from posters on this caving forum, who probably rely on such devices more than climbers.

> Its a bit sobering to find that the "ideal" device can still fail with serious consequences. My take is that there is no such thing as a totally reliable device but that the shunt which has been widely used by climbers for many years, if used with knowledge of its likely failure mode but backed up with a reserve device may well be as safe as anything. But who knows?

pec:
I am unclear what your level of expertise is with regard to rope access work and/or 'guided type fall-arrest devices'?
I can confirm that many 'guided type fall-arrest devices have vulnerabilities if they are used on a heavily pre-tensioned fixed rope. Note the term 'heavily pre-tensioned' fixed rope. In other words, to induce this failure mode - you would need to heavily pre-tension your fixed rope.
In the world of rope access, this could occur during a 'rescue from below' scenario where a heavily laden rescuer attempts to ascend on the victims backup safety rope (the same rope that the 'fall-arrester device' is attached to).
This type of scenario will not occur in recreational climbing. Also, the nominal weight acting on the device is one person (not 2 persons).
Here is a link from ISC: https://www.iscwales.com/Blog/RP500-Rocker-suitable-for-2-person-load/
And some more links which are interesting:
http://itrsonline.org/wordpress/wp-content/uploads/2015/02/013.Reed_.2014.p... 

What some commentators fail to identify is that in recreational climbing applications, you ideally want to use a device that works hands-free!
There are people that will muck about with all sorts of gadgets and give advice on how to use various systems for rope solo activities. Almost without exception, these people fail to point out that their system doesn't work hands-free (in both up and down mobility).
The ultimate hands-free gadget is the Petzl ASAP but, its not cheap and you cant gently sit back and rest on it (it needs a velocity increment to lock - about 2.0m per second).
The 'Rocker' and other guided type fall-arrest devices such as the Camp 'Goblin' will lock if you sit back and take a rest.

In the world of outdoor recreation, it seems that $ cost (ie expense) is a key driving factor in affect the mindset of the climber. Climbers generally will seek out the lowest cost solution to their needs - and in doing so, potentially cut corners, use products outside of their design specifications or generally take unnecessary (ie preventable) risks. All to save a few dollars...

There are some who well sing their tune of; "I've always used [inset your favourite system here] and never had a problem".

In my view, this is a false positive - and ignores the underlying risks.

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 simondgee 11 Jul 2019
In reply to agent_smith:

Just curious why you have posted 2 long replies based around devices and systems of work/operation typical of IRATA/rope access type 2 rope systems and but based your assumptions on a single rope? when for pretty much all protected ascent would want to conclude with an abseil. The ISC Rocker, along with a list of other devices are not designed for what we want to do for self protected top roping so yes folks will understand and use systems that are in effect field tested and proven in the minds of the user...so its far from a false positive and inherently assumes the risk of using equipment that hasnt been designed and tested for climbing use (this context).

Post edited at 00:39
 agent_smith 11 Jul 2019
In reply to simondgee:

Happy to engage with you at an intellectual and respectful manner.

The underlying assumption is to seek a device (or system) that will catch/arrest a fall hands-free and without the deliberate intervention of the climber.

The other assumption is that gravity is universal in its effect - it does not change when crossing national boundaries or continents.

Backup fall-arrest devices are (obviously) designed with the intent of arresting a free-fall. That is is their stated purpose. That is what they are designed to do.
Now, whether the user is wearing long pants, long sleeve shirt and steel cap boots or is wearing typical recreational clothing is irrelevant. The device is designed to lock on the rope regardless of location on the Earth's surface or user demographic.

So whether you are a male, a female, a recreational climber or a rope access worker makes no difference. A guided type fall-arrester is built to arrest a free-fall - that is its stated and intended purpose.
Many guided type fall-arrest devices are in fact designed and rated for a 2 person free-fall arrest. The ISC 'Rocker' is one such device (there are several that are rated as such).

Logically, a guided type fall-arrest device that is also capable of arresting a 2 person payload is qualified to arrest a 1 person payload. In recreational rope solo climbing, we are (of course) applying a 1 person payload. So the 'Rocker' has a good margin of safety built-in.

Using a guided type fall-arrester that works 'hands-free' is a desirable quality. If you have to constantly manipulate a device/system in order to make progress - that is undesirable.
Also, if a device/system can be defeated by a 'panic grab' reaction, that is exposing the user to a certain level of risk. The instinctive reaction to 'grab' when suddenly free-falling is strong in humans. It would take a disciplined person who is well conditioned mentally to counter-act this innate instinct to reach out and 'panic grab'. This was one of the driving reasons for banning the Petzl Shunt as a guided type fall-arrest device.
 

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 simondgee 11 Jul 2019
In reply to agent_smith:
Thanks however the question was why you assumed a single rope (no redundancy and no ready means of change over for descent). As a climber ( i assume you are?) what is your set up for self protected top roping?

Also what is the difference between the ISC Rocker and SAR Rocker...from my recollection SAR products was set up by the designer of the Rocker?

 agent_smith 11 Jul 2019
In reply to simondgee:

So there are a few things embedded here that must be pointed out and made 100% clear:

1. Your point re using a single rope is not a sustainable argument.
Consider the typical sport climber who leads on a single EN892 dynamic rope. If that rope fails (for any reason) - the outcome would be catastrophic.
In order to get around the risk of lead climbing on a single rope - you could lead with 2 ropes (ie two 'half' ropes).
However, you would have to find a means to enforce a rule that all lead climbing from this day forward must be carried out using a double rope system. I am not sure if such a rule is enforceable or desirable?

2. When belaying a lead climber (or any climber) - you are using a single belay device that is united with a single carabiner. If the carabiner fails - the outcome would be catastrophic.
You would have to enforce that all belay duties are undertaken with 2 carabiners (so you have redundancy). Also, if the belay device fails, the outcome would be catastrophic.

3. A belay person typically grasps the climbing rope with one hand. When the lead climber falls - the system is dependent on the skill and diligence of the belay person to not to let go of the rope (assuming a tubular device such as an 'ATC'. If the belay person lets go of the rope - the outcome would be catastrophic. This is a human factor. You would have to consider that belaying with one hand using a fallible human is unsafe - and not permitted. There is no inbuilt redundancy for a human belayer holding the rope with one hand...a mistake could be fatal.

4. Climbers only wear one harness - if that harness fails - the outcome would be catastrophic. To avoid the risk of a single harness failure - you would have to enforce that all climbers wear 2 harnesses (so you have redundancy).

5. Recreational abseiling and caving is typically performed on a single rope. If that rope fails - the outcome would be catastrophic. You would have to use twin ropes to have redundancy. I am not sure how you would enforce that all abseilers/cavers must use twin ropes whenever they undertake their sport?

Before addressing your point re using a single fixed rope (for rope solo climbing) - I respectfully request that you address each of the 5 points I have identified.

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 SenzuBean 11 Jul 2019
In reply to Presley Whippet:

Can anyone advise on the safety of this setup? https://blog.weighmyrack.com/guide-to-best-setup-for-toprope-tr-soloing/
It seems like a good compromise between safety and ease of use, but I'm a total novice at rope soloing.

 agent_smith 11 Jul 2019
In reply to SenzuBean.

The link you gave points to yet another configuration in an ocean of endless configurations.
This author of that setup is obviously oblivious to the fact that his 'rig' all still comes down to one (1) fixed rope. If that rope fails - its hast la vista.

But, as I already pointed out, nearly all outdoor recreation activities are carried out on a single rope anyway. There is generally no backup rope.

This is where the waters get murky.
If you want to achieve true redundancy, everything must be doubled! And that includes using two 92) fixed ropes, 2 independent anchors (one for each fixed rope), 2 separate attachment points to the devices (one for device), etc.

At some point, the redundancy issue would have to reach a logical and sensible conclusion... for example, it would be silly to expect a climber to wear two (2) harnesses (in case one harness fails).

Industrial rope access is always carried out on two (2) independently fixed ropes that are independently anchored. The outdoor recreation world works differently. Most climbers / abseilers / cavers would typically use a single rope. Note that some trad climbers like to use double ropes - and I applaud them for doing so.

I would also point out that using any toothed device as a fall-arrester is just plain silly. Note that I am specifically referring to toothed devices in a fall-arrest situation.
Richard Delaney has written an excellent report (and video) on the effects of falling on a toothed device.
Link: https://www.ropelab.com.au/members-falling-on-teeth/

Again, you will get people on various forums stating they happily use toothed devices as a fall-arrester - but they are likely ignorant of the risks of doing so (refer to R Delaney report).

They issue (which I have already pointed out), is having a system that works 'hands-free' in both up AND down mobility. This is something that is overlooked by many commentators...

3
 Alun 11 Jul 2019
In reply to Presley Whippet:

Hi,

Skipping over the long debates to add my two cents. 

I have (top)rope soloed many times to work sport climbing projects on my own. I use two microtraxions on a regular dynamic rope, doubled up. The trick is to get them as close as possible to your body, and to have the rope weighted at the bottom, and then they slide up fairly easily.

There are plenty of articles (search for Steph Davis) and videos (Dave Macleod) on the internet.

Whatever you do please please please double triple check everything you do. I consider myself a knowledgable climber with 30 years experience under my belt, but the first time I went rope soloing I made a couple of mistakes that I got away with due to ‘backing up my backups’. 

Don’t forget you are on your own (that’s the point!) so if anything goes wrong, help may be hard to come by.

Be safe!

 summo 11 Jul 2019
In reply to Presley Whippet:

Ignoring the all above. But echoing the last post.

There are a few devices that will work, that aren't so aggressive they'll wreck your rope or cut it. But I would always back up with a loop or something every few metres. Some devices with teeth, ribs, or little spikes are made for just hauling loads, ascending as a caver or  pulley systems, they are not made for you to even drop 1m onto them. Test them, even with a shunt body position is important, if you try and stay upright too much your body/harness waist belt can mind the lever and stop it fully locking off. Test them near the ground first. 

Edge protection is critical if you are working a route and might fall or even just gently weight the rope several times. 

Anchors should be bombproof, without any doubt in your mind, plus zero risk they would lift or work out. 

Rope, try and use pre stretched or at least the thickest climbing rope you can. Less stretch will make a difference. Always double check. Carry a spare device and or prusiks. 

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 JMarkW 11 Jul 2019
In reply to Presley Whippet:

I dont do a lot but when I do I use a petzl croll, chest harness slightly done up, static rope and no slack in the system. Weight the rope at the bottom with a bag.

I find the rope is very smooth through the croll. Rope protectors on edges and rebelays over the edge. 

Dave McLeod has a great YouTube video on this. 

Cheers

Mark 

 simondgee 11 Jul 2019
In reply to JMarkW:

I'm same as you Mark but use a second rope (well the other half anyway) with a gri gri 1 as a second device (makes transfer back abbing back down quicker easier and safer and provides my preferred level of redundancy... like Aluns twin traxions)...and like Alun I've been around long enough to appreciate its not to be taken lightly.

 simondgee 11 Jul 2019
In reply to agent_smith:

Redundancy in device not rope with the bonus of switch to Abseil being easier more efficient and safer. 

Climbing is a risk appetite sport where we subjectively chose our own tolerance, In work no such discretion is allowed.  As far as I know no magic bullet device has been designed, tested and certified and currently sold for recreational climbing, self protected top roping system and all can be compromised (including ISC/Troll/SAR Rocker) ....Please do share if there is one. So, as climbers we use devices and systems that satisfy our own risk tolerance levels with understanding of limitations... for some it is to only ever top rope with a belayer, for others it is leading, on-sight soloing etc. The same risk appetite approach applies when using devices 'off label' with systems developed through shared knowledge and experience. For me it is in redundancy is the vulnerable element of the system (sic) the rope grab...while it is clear you are not a climber would be good to hear your evidence based solutions in the scope you do work rather than citing only problems. So whats is your self protected top rope recommendation? Thx.

In reply to Presley Whippet:

I guess there is very good reason the practice is known as "shunting". 

 agent_smith 11 Jul 2019
In reply to simondgee:

simondge - as stated, happy to engage with you on an intellectual level provided it remains courteous and respectful.

I outlined 5 key points in a previous post. Did you read them?
They are no easy to ignore as they go right to the heart of the concept of 'redundancy'.
Ultimately, you would need two (2) of everything to be truly 'redundant'.

Your comment re "Being able to switch to abseil descent easier'" is a relative concept. Transitioning from fixed rope ascent to abseil descent is 'relatively simple' if you perform the maneuver from a static hanging position (so you have both hands free to work with).
By definition, if a person makes the conscious decision to undertake rope solo climbing activities, it means they have the requisite skill set and experience. it is assumed that a total novice would not attempt to climb rope solo or to do what I refer to as 'live experimentation' at height.
There are 4 levels of competence... and a rope solo climber would need to be at the level of:
[ ] consciously competent; or
[ ] unconsciously competent

I already pointed out to you that there are purpose built devices on the market that are intended to be employed as fall-arrest devices.
I mentioned that the 'Rocker' is one such device - and so is the Petzl ASAP.
These products are fit for their intended purpose - and specifically designed to arrest a free-fall.
I also mentioned that the Petzl Shunt is no longer recommend by a wide cohort of skilled practitioners - for several reasons - which includes the fact that it can be defeated via an instinctive 'panic grab' reaction.

I also mentioned that 'toothed' devices - that are not specifically intended to arrest a free-fall - should not be employed in such a role. The Petzl ASAP is a 'toothed' device but, it has been specially designed to lock on to a synthetic low elongation rope (eg EN1891) without severing it. It is also supposed to be used with a tear-web shock absorber lanyard.

As you would be aware, there are no laws governing recreational climbing activities. That is, in outdoor recreation, it is largely a free-for-all and you can go and purchase PPE and climb as you please. A recreational climber has the right to remove him/herself from the Earth's gene pool (known as a 'Darwin award') if s/he chooses to do so.

There is no universal standard for the knowledge and skills in recreational climbing. And this is part of the reason why you see these types of posts on social forums - because everyone has an opinion and their own concept of what is an 'appropriate' risk level. And that's fine...

I also note that you wrote: ... "while it is clear you are not a climber:...

I am unclear as to how you reached that viewpoint...?
For the record, I started my climbing/roping career in 1983 and have been professionally involved with the sport full-time since 1983. And since 1996, I expanded my work into both industrial rope access and specialist vertical rescue (working with paramedical teams, mine rescue teams, helicopter based teams, etc). I also have a reasonable skill set in mountaineering - having climbed many mountains (but none above 7200m).
 

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 simondgee 11 Jul 2019
In reply to agent_smith:

Thanks... I still have no idea idea what your solution/system of choice is ? (...but then I don't think you do). 

>>>"while it is clear you are not a climber:...I am unclear as to how you reached that viewpoint...?<<<
lets call it thin slicing...









 

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