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Politics Is certainly not really the reason for this. When petzel release warnings/ statements about configuration/ application it's not some marketing ploy and they also go to great ends to word them in a fastidious manor.

 

As well as it may appear to function allot of people that use this setup repeatably load the setup such that the ZZ takes 100% (/nigh on) of

the load and this could have serious consequences for the device, it's longevity and safety of the user.

 

In arb most climbers are frequently exposing their systems in a 'fall arrest' scenario, as an industry we haven't really faced up to this fact yet. Many of our systems can withstand fall arrest forces and (many/ some) may even preform relatively well in this situation and (I beleive) its due to this we see very few injuries/ accidents where this 'incorrect application of equipment' is a significant factor.

 

Some of the recent additions of arb climbing gear although developed to WP and ascender/ descender standards will have been developed with this exposure in mind, some have (by chance) covered this base and some won't have at all.

 

Does anyone on here know how well the pictured systems would preform if they were subjected to these 'highly possible' scenarios? From a mechanical performance perspective I'd guess that some of these pictured config's will perform much better than others.

 

Lolering as many firms kit as I do i get to see & hear quite allot of 'anecdotal' accident reports of accidents/ near misses which may well have gone unreported and un-publicised, sometimes it's due to 'experimental' configurations like this.

 

I'm not necessarily saying don't climb on these systems just be sure you're making informed decisions and are happy to accept the potential consequences (in this instance potential irreparable equipment damage not covered by warranty or even a fall) Also consider the guys on site and how that might effect them, are they happy to whiteness and be involved in these consequences?

 

Trailing/ developing gear for/with major manufacturers you can be sure/ see that they've done serious amounts of testing before putting safet critical gear out to be field tested. Furthermore you typically have a written contract which may include insurance. The contract may also carry warnings about ensuring you are permitted to use such 'prototype' equipment within your workplace and go on to further details regarding people you work with to sign non-disclosure/ agree not to take photos etc.

 

Just be sure you're happy with the potential consequences, anyone can whap something together and witness that it 'holds/ functions'. To know what it's limits are or for how long it will function is not always know, quite often disregarded but it's probably fair to say it can never be 'known', certainly not without extensive field tests. Its true that not everything can be done in a lab/ on a test bench but IMO its best to start off with the mechanics & physics & on to labs/ test benches before handing it over for 'animal' testing by us arborists :001_smile:

 

 

 

I kinda .... don't like how you've got the name Petzl ...wrong ?

 

Along with the fact ....your talking twaddle .... but some of your mush makes sense .... : )

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Like Petzl tested the ZZ mk1?

 

 

Sent from my iPhone using Arbtalk

 

there was me thinking i wrote "it's probably fair to say it can never be 'known'" in relation to prototype testing...........

 

Some said it was utter twaddle that a karabiner could be 'level loaded' in a real life situation. Then someone fell form exactly that off a lowering rack

 

The more aftermath of a serious accident i'm partied to the more 'mushy' perhaps I've become. Seeing someone (usually so jovial in disposition) who hasn't slept for over a month with their ash grey skin and weight loss kinda brings it home. Especially when better equipment selection/ reading/ understanding instructions could have prevented I life changing accident. Climb safe.

 

fast typing + dislexeea = pour spelling :lol:

 

My experience of Petzl and field testing their equipment is obviously subjective, but probably not twaddle. I'd find it hard to level any major criticism in their direction in those respects, they do much better than most as far as responsibly developing/ innovating equipment goes. their statements on application and compatibility over the years have been pretty balanced IMO.

 

There are major differences in the pictured configurations pictured and they will perform very differently in terms of static strength, dynamic strength, dynamic performance and practical performance. I really do think it's great that people are willing to risk their lives to further innovation, so long as it's a conscious decision that is :151:

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You make some very good points mate.

I'm using the configuration with my eyes very much open, believe me.

I am aware of the possibility of the ZZ being 'stretched' in certain scenarios, and bearing all the weight single line, which wouldn't be great.

 

Ultimately, the weakest link in the integrity of my system will most commonly be the strength of some of the manky trees I climb.

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Politics Is certainly not really the reason for this. When petzel release warnings/ statements about configuration/ application it's not some marketing ploy and they also go to great ends to word them in a fastidious manor.

 

As well as it may appear to function allot of people that use this setup repeatably load the setup such that the ZZ takes 100% (/nigh on) of the load and this could have serious consequences for the device, it's longevity and safety of the user.

 

In arb most climbers are frequently exposing their systems in a 'fall arrest' scenario, as an industry we haven't really faced up to this fact yet. Many of our systems can withstand fall arrest forces and (many/ some) may even preform relatively well in this situation and (I beleive) its due to this we see very few injuries/ accidents where this 'incorrect application of equipment' is a significant factor.

 

Some of the recent additions of arb climbing gear although developed to WP and ascender/ descender standards will have been developed with this exposure in mind, some have (by chance) covered this base and some won't have at all.

 

Does anyone on here know how well the pictured systems would preform if they were subjected to these 'highly possible' scenarios? From a mechanical performance perspective I'd guess that some of these pictured config's will perform much better than others.

 

Lolering as many firms kit as I do i get to see & hear quite allot of 'anecdotal' accident reports of accidents/ near misses which may well have gone unreported and un-publicised, sometimes it's due to 'experimental' configurations like this.

 

I'm not necessarily saying don't climb on these systems just be sure you're making informed decisions and are happy to accept the potential consequences (in this instance potential irreparable equipment damage not covered by warranty or even a fall) Also consider the guys on site and how that might effect them, are they happy to whiteness and be involved in these consequences?

 

Trailing/ developing gear for/with major manufacturers you can be sure/ see that they've done serious amounts of testing before putting safet critical gear out to be field tested. Furthermore you typically have a written contract which may include insurance. The contract may also carry warnings about ensuring you are permitted to use such 'prototype' equipment within your workplace and go on to further details regarding people you work with to sign non-disclosure/ agree not to take photos etc.

 

Just be sure you're happy with the potential consequences, anyone can whap something together and witness that it 'holds/ functions'. To know what it's limits are or for how long it will function is not always know, quite often disregarded but it's probably fair to say it can never be 'known', certainly not without extensive field tests. Its true that not everything can be done in a lab/ on a test bench but IMO its best to start off with the mechanics & physics & on to labs/ test benches before handing it over for 'animal' testing by us arborists :001_smile:

 

def not a load of twaddle imo just a detailed post about the safety of configuring your own climbing system out of different pieces of gear that may or may not be designed to work that way, thanks for posting :thumbup1:

carl

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....I am aware of the possibility of the ZZ being 'stretched' in certain scenarios, and bearing all the weight single line, which wouldn't be great....

 

I do not own a ZZ so cannot test this myself but is this a true problem? There is a large amount of information on how hitch cord responds to overload conditions. Does the ZZ not slip at a predictable load? Will it continue to grip until failure of it or the rope?

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Three are a few papers here and there on hitches slipping/ not slipping in an overload situation yes. Many of them centre on the use of prussics as 'load limiters' on track lines and all of the latest research suggests not (Ie they do not reliably slip and can be pulled until either line or prussic breaks)

 

Furthermore i'm happy to confirm that in my own research this has been confirmed. I have pulled many friction hitch based Ddrt systems (and srt ones) to destruction without the need for a stopper knot under the hitch. The hitches have gripped under both dynamic and static loads until the systems weakest component has broke. in these tests some hitches have neither consistently gripped or slipped despite efforts to tie, dress and set them to exacting standards.

 

In some other testing in which i've been involved in on certain mechanical devices we've found they (rather surprisingly to me) are also not always consistent in their slippage either. The norm which they are sometimes tested to allows for them to slip at low loads but does not require it, in some a stopper knot is allowed to be placed under the device to achieve a break strain. Even in devices where slippage is a component of the norm to which they are certified other workplace variables altered results significantly wear is a major factor as was rope weight, wet line, line diameter and even brands of line of the same diameter certified to the same norm.

 

As such i would not personally presume the ZZ will slip at a predictable load under work-site conditions on a variety of lines moreover i would not presume that in the event of an overload/fall the force would be shared by an un-engaged wrench.

 

If this didn't cause an immediate problem/ failure i'd certainly say it had implications for the longevity/ wear of the device, repeated loads like this would exacerbate this prognosis.

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Have you read Paolo Bravarescos work on hitchs? It is not really possible to make generalisations on how a hitch will respond without more details.

 

You are correct that one should not presume anything about our equipment. I was curious if any testing had been done on how the ZZ responds in the specific overload conditions that were mentioned.

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