I had hoped that my presentation at (1) was lucid enough, but I may be wrong. I will try to describe the easily memorizable method I use for tying those bends one more time, with other words.
This method comes in two steps : first, we build a loose knot "base", and then, using this base, we tie the final bend, driving the two working ends of the two links of the bend through the appropriate, indicated paths of the loose knot base.
Imagine two inter-linked half-turn bights in a 3D space configuration, like two rope-made links of a chain. Moreover, imagine those links laying in two planes, the one vertical and one other horizontal. (see the first two attached pictures). Notice the specific relative position of the standing and working ends in this configuration. We will return to this later on.
In each link, the standing end and the working end are crossed at a point. Hold the two inter-linked bights by those points: hold the first link with the thumb and index finger of the one hand, keeping its plane vertical, and the second link with the thumb and index finger of the other hand, keeping its plane horizontal.
Rotate 90 degrees any of the two links, rotating the wrist of any of the two hands, in a counter-clockwise direction. Doing this, the 3D space shape becomes a 2D one. Now, look at this shape from the "front" side: it is the side where the shape of the two interlinked bights looks like the "symmetric" shape at picture #3. That means two things :
1. The working end ( and the standing end ) of each link should be shown to leave the loose knot towards OPPOSITE directions, in relation to the working end ( and the standing end ) of the other link.
2. The working end of each link should be shown to pass OVER the standing end, in both links.
That is the knot "base" on which we weave the final bend.
We can see those 7 "black holes"
in this shape. I label them conveniently, as they are shown in the picture s frame: upper Left (uL), lower Left (lL), upper Right (uR), lower Right (lR), Left (L), Right (R)), and Centre (C).
From that point, you just have to pass the working end of each one of the two links, through the specific "hole" indicated by the label of the bend, thus completing each one of the two interlinked overhand knots. The labels that should be followed to tie a particular knot are written in a certain order : the
first indicate the "hole" from which we should pass the working end of the
first, left link, and the
second indicate the "hole" from which we should pass the working end of the second, right link Fot example : In the
lR - uL bend, we have, first, to pass the working end of the first., left link through the lower, Right hole (lR) , and then, we have to pass the working end of the second, right link, through the upper Left hole (uL).(See attached picture)
Forming the shape, it is better not to have too narrow, or two wide "holes". The knot is tied easier, if we leave just the minimum required room for the working end o pass through: one rope diameter. Doing this, the subsequent dressing of the knot becomes much easier, and unambiguous. ( Note: In the attached picture of the loose lR-uL bend, the "holes"are left wider, only for presentation purposes)
I hope I offered some (almost
) comprehensible written instructions for the tying of this beautiful, most symmetric bend. Of course, - as it always happens in the case of verbal instructions for tying knots , the words are not enough, or they are too much, and they tend to confuse/ perplex the reader, more than to help him !The pictures are telling the most of what has to be told here. The interested reader is kindly requested to ask me any question, and, also, if he wishes, to teach me how I could better describe this method, so it becomes more comprehensible and memorizable - or even how to tie those knots using another, different, and possibly better way.
1)
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