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Knot exam paper... test your current knowledge!


Original Post
Mark Gommers · · Townsville, Queensland · Joined 7 days ago · Points: 0

Link: http://www.paci.com.au/knots.php 
Scroll down to #5 in the table.
Not sure how much longer I will keep this free in the public domain - download a copy while you can.
This exam might also be of some interest to instructors and outdoor educators.

Please note that this exam paper is not intended solely for climbers! It is also written to suit industrial rope access operators and vertical rope rescue technicians.
To ensure you are viewing the latest version - please hit your refresh button (some computers hold pdf files in cache memory) - and it keeps loading the older cached version instead of refreshing the newer version.

Happy knotting from Mark Gommers

rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526

Whoa...some interesting stuff if you are into knots, and some very useful climbing-related items, but overall  more than any climber has to know.

Fran M · · Germany · Joined Feb 2019 · Points: 0

thanks!

SinRopa · · parts unknown · Joined Sep 2013 · Points: 30

This is great.  Is there an answer sheet we can reference too?

Fran M · · Germany · Joined Feb 2019 · Points: 0

Mark,
I have been reading the material in your website and noticed you advice for a 200mm minimum tail length for a Figure of 8 knot. I have seen Edelrid and Mammut manuals advice 10cm minimum tail length.

Could you explain the difference? I notice the information is not intended for climbers only but I am curious in any case.

Mark Gommers · · Townsville, Queensland · Joined 7 days ago · Points: 0
I have seen Edelrid and Mammut manuals advice 10cm minimum tail length.

You would need to provide the links (URL) so I can see the exact same content you are seeing.
In any case, I had a look at the Mammut website here: https://www.mammut.com/int/en/  and then I had a look at the Edelrid website here: https://www.edelrid.de/en/ 

I found nothing specifically dealing with knots and knot safety at the Mammut website.
However, i did find this pdf file on the Edelrid website: https://www.edelrid.de/en/sports/knowledge/pics/2018/Seilfibel_EN_ANSICHT.pdf?m=1536742517 

The Edelrid pdf document contains several glaring errors (and this does not surprise me).
You have to keep in mind 2 key factors:
1. Edelrid is a manufacturer - and their core business is making things. They are not knotting theorists (it's not their core business - and that's perfectly understandable).
2. English isn't their first language - German is their first language - so there will always some translation errors.

Just because a manufacturer makes climbing equipment (eg ropes and other PPE) this does not by itself grant expert status about knots and knotting.

Anything that is published by a manufacturer has usually been scrutinized by a legal professional.
Suing people is a national sport in the USA - and US lawyers are eager to flex their muscles in US courts.
I'm not sure if suing people is a national sport in Germany - but since they sell their products to the US market - they would certainly be aware of product liability and the need for user instructions.
User instructions are written to provide a first line of defense (in legal terms).

If what you say is in fact the current published doctrine of Edelrid and Mammut - I would suggest the legal advice they received is flawed.
Most people would agree that some residual tail is necessary with knots used in life critical applications. There are 2 extremes:
1. Have zero tail (ie no tail); or
2. Have ludicrous lengths of tail (ie of such a length that you could literally trip over it).

Both of these options are undesirable.
A balance needs to be found - and it must be 'reasonable'.
There are 3 different types of roping user groups as follows:
1. Outdoor recreation (rock climbers, cavers, canyoners, challenge ropes course parks, etc)
2. Industrial roping (eg rope access, arborists, tower workers, roof workers, etc)
3. Public safety (eg vertical rescue teams, YOSAR, Seals/Delta force, SWAT, Police rescue, Fire rescue teams, etc)

Logically, you need one rule to bind them all - not 3 different rules.
All 3 user groups use knots, ropes, harnesses and helmets.
Gravity acts in the same way for each user group.
US Navy SEAL teams haven't figured out how to isolate gravity - and neither have rock climbers.
The 200mm rule is the common ground for all groups.
Note that 200mm tails are not necessary in 'Prusik loops/slings' formed from 6mm cord - tails can be shorter.
Tail length in fact varies from knot type to knot type.

Hope you liked my long-winded answer :)

I may not always respond - I'm usually busy (sorry).

PS (edit) I suggest that you download the PACI protocols document from this webpage: http://www.paci.com.au/guides.php (scroll a long way down to 'Learning support materials' - its at #3 in the table). I'm not sure how much longer this document will remain free in the public domain...download copy while its still free!
kevin deweese · · Oakland, Ca · Joined Jan 2007 · Points: 521
SinRopa wrote: This is great.  Is there an answer sheet we can reference too?

This would be incredibly helpful if it's actually going to be used by those of us in institutional settings as you suggested 

Noah R · · VT · Joined Nov 2018 · Points: 0

"This document is password protected. Please enter a password."
Bummer I wanted to check it out. 

rgold · · Poughkeepsie, NY · Joined Feb 2008 · Points: 526

password is "thankyou"

jnowis · · Unknown Hometown · Joined May 2008 · Points: 35
Noah R wrote: "This document is password protected. Please enter a password."
Bummer I wanted to check it out. 

Noah R, check out the previous page, the one where you selected the PDF. The description provides the password (hint "thankyou").

Jim Titt · · Germany · Joined Nov 2009 · Points: 490
Mark Gommers wrote:
You would need to provide the links (URL) so I can see the exact same content you are seeing.
In any case, I had a look at the Mammut website here: https://www.mammut.com/int/en/  and then I had a look at the Edelrid website here: https://www.edelrid.de/en/ 

I found nothing specifically dealing with knots and knot safety at the Mammut website.
However, i did find this pdf file on the Edelrid website: https://www.edelrid.de/en/sports/knowledge/pics/2018/Seilfibel_EN_ANSICHT.pdf?m=1536742517 

The Edelrid pdf document contains several glaring errors (and this does not surprise me).
You have to keep in mind 2 key factors:
1. Edelrid is a manufacturer - and their core business is making things. They are not knotting theorists (it's not their core business - and that's perfectly understandable).
2. English isn't their first language - German is their first language - so there will always some translation errors.

Just because a manufacturer makes climbing equipment (eg ropes and other PPE) this does not by itself grant expert status about knots and knotting.

Anything that is published by a manufacturer has usually been scrutinized by a legal professional.
Suing people is a national sport in the USA - and US lawyers are eager to flex their muscles in US courts.
I'm not sure if suing people is a national sport in Germany - but since they sell their products to the US market - they would certainly be aware of product liability and the need for user instructions.
User instructions are written to provide a first line of defense (in legal terms).

If what you say is in fact the current published doctrine of Edelrid and Mammut - I would suggest the legal advice they received is flawed.
Most people would agree that some residual tail is necessary with knots used in life critical applications. There are 2 extremes:
1. Have zero tail (ie no tail); or
2. Have ludicrous lengths of tail (ie of such a length that you could literally trip over it).

Both of these options are undesirable.
A balance needs to be found - and it must be 'reasonable'.
There are 3 different types of roping user groups as follows:
1. Outdoor recreation (rock climbers, cavers, canyoners, challenge ropes course parks, etc)
2. Industrial roping (eg rope access, arborists, tower workers, roof workers, etc)
3. Public safety (eg vertical rescue teams, YOSAR, Seals/Delta force, SWAT, Police rescue, Fire rescue teams, etc)

Logically, you need one rule to bind them all - not 3 different rules.
All 3 user groups use knots, ropes, harnesses and helmets.
Gravity acts in the same way for each user group.
US Navy SEAL teams haven't figured out how to isolate gravity - and neither have rock climbers.
The 200mm rule is the common ground for all groups.
Note that 200mm tails are not necessary in 'Prusik loops/slings' formed from 6mm cord - tails can be shorter.
Tail length in fact varies from knot type to knot type.

Hope you liked my long-winded answer :)

I may not always respond - I'm usually busy (sorry).

PS (edit) I suggest that you download the PACI protocols document from this webpage: http://www.paci.com.au/guides.php (scroll a long way down to 'Learning support materials' - its at #3 in the table). I'm not sure how much longer this document will remain free in the public domain...download copy while its still free!

Hmm, the use of climbing ropes and the instruction on knotting them is NOT in the remit of the manufacturer.

Exactly how many fig 8 knots have you tied in a rope and drop tested to destruction? How many do you think Edelrid have done? They must have at least one guy full time testing them for QC purposes and probably more and then the development guys..... I know personally someone that has spent 30 years breaking climbing equipment all day every day, he´s an expert.

Noah R · · VT · Joined Nov 2018 · Points: 0
rgold wrote: password is "thankyou"
Thanks for that.

Super cool knot exam. I am a fan. Definitely agree that most climbers do not need to know all of that but it still is fun for knot geeks.

Gave me some ideas for sure. 
TBlom · · Unknown Hometown · Joined Jun 2004 · Points: 360
animatedknots.com/

for the rest of you knot geeks
Alan Coon · · Longmont, CO · Joined Feb 2013 · Points: 175

Oh wow very cool.

Fran M · · Germany · Joined Feb 2019 · Points: 0

Thank you for your detailed reply, although I think I have more questions now than before!

First, regarding the source, I could not find an online document but here is a picture of the instructions attached to a Mammut infinity 9.5 non-treated rope manufactured in 2018 (instructions say 02/16). For Edelrid I could not find it yet but will report back after a more thorough search.

Second, the questions:
1. How do you arrive to the 200mm number as rule? I guess by testing for the worst case scenario which would probably involves user groups 2 and 3. If so, I am curious as to what that scenario consists of. An F8 tied on a wet stiff rope, without tension, attached to a vibrating structure while dangling in the wind?

You mentioned "Tail length in fact varies from knot type to knot type.Scanning through the Protocol document, as suggested, I found:

100mm - Double Overhand noose (pp. 51, 57 - clip in, connectors)
200mm - Double fishermans, Zepelin bend, Offset choked overhand bend (p. 93 - joining knots)
2.0m     - Bowline (ABOK 1034 1/2) as master point for rescue stretcher

2. Regarding the joining knots, in their instructions, Mammut advices 30cm tails for the offset overhand (so does Petzl, no binding turn though) for rappelling. Does the binding turn account for the difference?

(p. 184 - Outdoor recreational anchors - life support bearing knots)
  20mm - 5-7.9mm cord   (4:1 ratio)
100mm - 8-8.9mm rope (10:1 ratio)
200mm - 9-11 mm rope (20:1 ratio)

3. Also, I have heard the "tail length of 10-fold diameter" rule many times, albeit not with ranges, but never found a source before. These are from testing as well? Maybe question is connected to number 1.

Thanks again and looking forward to your comments.

Mark Gommers · · Townsville, Queensland · Joined 7 days ago · Points: 0

Hello 'Fran'.
Thanks for your questions - it is all drifting off-topic unfortunately.
I am not sure what the forum rules are?

I would point out that you are asking for my advice and consultation - which I can do - but not here.

I suggest that you consider the following options:
1. We communication privately (ie via email?)
2. Start a new topic thread titled 'Tail lengths for knots used in life critical applications"

If you go with option '2' - you'll get wider viewpoints from a number of sources.

Option '1' is something I'll consider - time permitting..

Ricard Delaney has conducted an interesting test showing the effects of 'slack shaking' and 'cyclic loading' on an F8 eye knot. As with all tests, it depends on how you test and what it is that you are trying to achieve. I would comment that slack shaking and cyclic loading are excellent tools to investigate security issues with knots.
Link: https://www.youtube.com/watch?v=lmQhVJ-1DYg 

...

As for supplying an answer / marking sheet for the knot exam paper - am unwilling to do outside of the PACI network on an open public forum - as it is PACI intellectual property.
You could figure out all of the answers with research, and time and effort (and I appreciate that this is not helpful to your cause).
Let me think about it - in terms of you approaching me privately - I may be able to consider your request from the point-of-view of 'internal review' for quality improvement. That is, maybe there is a way to get you instated as a member of the PACI review panel?

PACI is bound under Australian legislation to undergo continuous quality improvement - and we have to prove that we have done so to comply with our RTO obligations. So I think this might be a way forward... I'll have to figure out how to contact you privately to exchange email addresses??? I am not a geek and not 100% computer savvy in the digital age (sorry).

Kalli Schumacher · · Chanhasssen, MN · Joined Mar 2017 · Points: 1
Mark Gommers wrote: Hello 'Fran'.
Thanks for your questions - it is all drifting off-topic unfortunately.
I am not sure what the forum rules are?

Drifting off topic might as well be the rule here. 
If you go with option '2' - I could post my opinions but, there are risks of challenging long held beliefs and it has the unfortunate side-effect of me popping up on peoples radar screens in a negative way (in which I am reluctant to go down that path beause when you challenge long-held beliefs about knots and various fall protection concepts - it can evoke a strong 
I’d argue you’ve already achieved this side-effect by not answering a seemingly straightforward question on a questionable safety decision that you seem to be teaching to instructors. I think most would agree 200mm is much too short for a tail on a figure eight on a single rated rope. I think anyone who clicks on this thread is interested in learning and therefore would be interested in hearing you out on your tail length opinions.
As for supplying an answer / marking sheet for the knot exam paper - am unwilling to do outside of the PACI network on an open public forum - as it is PACI intellectual property.
Wait but then why supply the test in the first place. 
Jim Titt · · Germany · Joined Nov 2009 · Points: 490
Kalli Schumacher wrote: Drifting off topic might as well be the rule here. 
I’d argue you’ve already achieved this side-effect by not answering a seemingly straightforward question on a questionable safety decision that you seem to be teaching to instructors. I think most would agree 200mm is much too short for a tail on a figure eight on a single rated rope. I think anyone who clicks on this thread is interested in learning and therefore would be interested in hearing you out on your tail length opinions.

Hmm, the AAC says 6", no more and no less, the DAV and the BMC 10cm and thats been the standard since I started climbing.

Guideline #1: Don't be a jerk.

General Climbing
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