KNOT TEST REPORT - summarized from video
Tester details: Richard Mumford
Company: Climbing Innovations
Application context: Tree climbing / arborist
Publication date: 29 Jan 2018
Testing lab type: Presumed ‘Pseudo lab’ (not a certified lab and not accredited by a third party agency)
Link to video: https://www.youtube.com/watch?v=UJ5DjjgDV6Q
This is another example of a tester aiming at the default #1010 Bowline - and presumably assuming that this is the only type of Bowline in existence. The author makes it clear that he is not a supporter of ‘the’ Bowline (preferring instead the #1053 Butterfly eye knot). It appears that Richard Mumford is oblivious to the fact that #1010 is not the only type of ‘Bowline’ in existence - and indeed, there is a class of eye knots known to be ‘secure Bowlines’.
Note: The author’s context is tree climbing.
Some criticisms (list is not exhaustive):
Testing commences at 12:47 elapsed time…
- The default mindset is to probe the MBS yield point of knots (ie pull-to-failure mindset).
- The author presumably places a lot of weight on knot ‘A’ versus knot ‘B’ pull-to-failure (presumably the winner of the contest is a superior knot? - This is an implied assumption).
- Dressing of the #1053 Butterfly assumes parallel eye legs (he does not investigate crossed ‘X’ eye legs)
- The author does not make a clear distinction between ‘eye loading’ and ‘through loading’ of the #1053 Butterfly eye knot (it is just assumed that viewers will know and understanding the differences).
- There does not appear to be any scientific rigor in terms of gathering a statistically valid sample (only appears to be a sample of 1).
- Vague on age of test cordage/rope.
- At 19:55 elapsed time he ‘ring loads’ the eye of #1053 Butterfly. Now in the form of a round sling, the load to reach the MBS yield point is naturally much higher than in linear loading profile (no supporting comments offered…just assumed that viewers will know this).
- At 21:05 elapsed time he tests #1010 in a ring loading profile (the author appears to be ignorant that this is a loading profile that is a known vulnerability of #1010…in comparison to #1034 1/2 which is resistant to ring loading. He missed an opportunity to use #1010 as a control against #1034 1/2.
- No firm conclusion drawn or stated from his tests. What was he ultimately trying to prove? Did he prove what he set out to do? What were his conclusion drawn as a result of his test efforts? It appears unclear or implied…
The above points are just quick observations…again, the list is not exhaustive.