Thanks for your questions Davide,
My answers are as follows:
1) Is there a document that shows the step-by-step process to tie all the inherently secure knots shown at page 77?
I'm working on it.
I will be uploading a knot tying study guide with high quality photos sometime in the next month or so.
In any case, these knots aren't too difficult to learn to tie.
Lees link Bowline is tied from a starting base called the 'Myrtle'. Once you have the 'Myrtle' its fairly straightforward.
Its also a variant of the 'Lee zep Bowline' (refer page 70).
2) I practiced with both versions of "Scott's locked bowline" on top-rope at the gym (I haven't tried lead falling on them yet), and I'm very happy with them so far. Is there any particular reason to choose one version over the other?
There are 4 variants of Scotts locked Bowline. In my mind, this is an elegantly simple and inherently secure 'Bowline'. I wish that I had thought of it before Scott
I personally like to use the variant based on #1034 1/2.
This variant is particularly resistant to radial cross-loading of the eye.
The simple #1010 Bowline is
vulnerable to radial cross-loading of the eye.
Variants based on #1010 or #1034 1/2 are all secure, with the #1034 1/2 variant even more resistant to radial cross-loading of the eye.
3) Among the 5 inherently secured bowlines on page 77, which one would you ultimately recommend for tie-in and lead falling, and why?
Please do not take any offense to my response to this question (I'm simply giving you an open and candid opinion).
The question is similar to EN892 dynamic climbing ropes - that is, which one would you ultimately recommend?
There are lots of choices for tying-in to a climbing harness - just like there are lots of choices of dynamic climbing ropes.
There are no laws governing rock climbing - other than rules you must obey at an indoor climbing gym (because it is a 'workplace').
You can tie-in with any of the inherently secure Bowlines - they are all 'safe'.
It comes down to your level of competence and confidence.
I prefer to tie-in with one the inherently secure Bowlines rather than the default #1047 Figure 8 eye knot (because I weigh 100kg and after a series of falls - #1047 can be hard to untie).
As a general rule, the more complex pathway the tail takes - the more secure the Bowline.
4) With inherently secured bowlines, is there any disadvantage to tying an additional "double overhand stopper knot" with the leftover tail (like the figure on page 72) anyway? I understand that this is not necessary with inherently secure knots, but I found that it prevents the excess tail from flapping around and poking me while climbing ;-) Is there any good reason for me NOT to do it?
Adding a
strangled double overhand knot (ie backup stopper knot) as a security device does nothing.
Best to learn to tie-in so that you always have between 100mm-200mm tail (not less than 100mm).
Add a 'backup stopper knot' increases the overall 'footprint' of your tie-in knot. In a tricky/desperate clip, you have to reach a bit further along the rope to clip in to a quick-draw. If using 'aid' while hanging on gear (or some would say 'shade') the stopper knot reduces the distance you can pull up and then reach the next hold.
I would like to prevent this post for becoming an ideological battleground.
and;
I read your post regarding Scott's linked bowline alleged vulnerability, and several people replied to you casting serious doubt regarding its reproducibility; however you didn't provide the information they requested, nor convincing evidence that what you described can realistically happen.
In the first instance, there are some very passionate knot tyers on this forum - and it is hard to decouple ideology from debate.
Everyone has an opinion. There are some who cling very strongly to traditional concepts (eg traditional views on the definition of a 'loop' a 'turn' and a 'bight', etc).
Some take offense at the slightest hint of a insult - and indeed, emotions take over and they typically retaliate or complain.
Its like politics - I think in the USA you have Donald Trump supporters and then you have those who support the other camp. Who's right and who's wrong? Probably history will decide.
In the second instance, in my professional opinion, there is no such vulnerability with Scotts locked Bowline.
The purported test is flawed on account of the following factors:
1. The tester did
not use
EN892 rope.
2. The tester used a knot specimen that was
not cinched tightly.
3. The tester created an enlarge 'eye' for the test - when tying-in for rock climbing, the eye is nominally between 70mm-120mm in size (no one ties-in with an enlarged eye).
4. The tester relied on a 'snag' caught inside the 'eye' - with a corresponding
longitudinal cross-load (ie opposing load at the tip of the eye is axially aligned with the SPart). This scenario is very remote in a real-world climbing activity. It is highly unlikely that a protrusion could snag a relatively small eye during a free-fall event or while being lowered. The climbers body would have to be in close proximity to rock face, and the eye of the tie-in knot would have to be enlarged (ie larger than normal) - both of which are improbable.
In a free-fall, the likelihood of a protrusion snagging a nominally tied 'Bowline' is
remote (ie minusculely small).
In the
highly unlikely event that a protrusion could snag the eye, the opposing force would be divided equally across both eye legs (not on a single eye leg). It appears that the tester directed his pulling efforts on the
outgoing eye leg rather than at the 'tip' of the eye. By biasing load on the
outgoing eye leg, along with low stretch EN1891 rope and a loose knot, it was possible for him to loosen the
nipping loop and and draw rope through the core. Once he got it started, he overcame 'inertia' and friction.
As a thought experiment, if the tester pulled on the
returning eye leg, no rope would flow through the core. This thought experiment suggests that the tester directed his pulling efforts on the outgoing eye leg.
NOTE:To the best of my ability, I have provided a response that is free of ideology and language that could be misinterpreted as insulting.
