- I can explain an easy and reliable way to tie an "Alpine Butterfly" (mid-line loop) with your eyes closed based on one of the pictures here if anyone is interested
I decided to explain this anyway
The "Alpine Butterfly Loop" is the standard mid-line loop for climbing.
- It doesn't require doubling the rope.
- It's strong, jam resistant, easy to untie even after being loaded, and easy to tie.
- The loop can be loaded in any direction
- It can be tied to a ring, but I wouldn't use it for that: the tying method is different and not as easy to remember
- It can also be used as a bend (joining two ropes) but I wouldn't use it for that either - IMO the Zeppelin and Carrick Bends are both better (see Grog)
- It's inconvenient to adjust the size or position of the loop after it's tied (retying is quicker)
The butterfly is actually two interlocked overhand knots like the Zeppelin Bend, but it's not so easy to see as with the Zeppelin. See Grog:
Step 1: Follow the animation at Grog to tie two or three Alpine Butterfly Loops exactly as shown there:
Get a feel for "setting" the knot after it's tied
Step 2: Look at the picture and read the text at the scouting site:
The picture is good, but don't try to tie it that way - Grog's method is much better (hence step 1)
Step 3 (my "tie it in the dark" method)
Keep the picture from step 2 in front of you for A to C.
(you can easily do this sitting in front of a screen)
A. Hang the middle of the line over your wrist (it's a mid-line loop so we don't want the ends close)
B. Take the line from the top/center of your wrist, twist it to make an "eye", and hang that over your thumb
Now the line is hooked on your thumb, crossing on top of your wrist, with ends to the left and right of your wrist
C. Make a second eye starting from the one on your thumb, twisting in the same direction (you get a different knot of you twist the other way) and grip the point where the line crosses with thumb and one or more fingers (I use thumb against the inside/center of my middle finger)
At this point we're at the first picture in the scouting link's description of the Alpine Butterfly Loop.
D. Use the other hand to take the top loop back and through the lower loop from underneath, as shown in that picture and set the knot. It's easy to make the loop longer as you do this.
It helps to grip one of the ends with the little finger of the hand controlling the loops (feels weird, but very helpful).
(D) feels difficult the first time, but it becomes easy quickly.
Note that if you've never tried this knot before, you have to practice how to set it after the knot is formed, and it won't necessarily look exactly like Grog's picture. Those two "parallel lines" in the center may look more like an "X", and the loop may have a half-twist. Once you learn how to set the knot, you can set it so it looks exactly like Grog's (though AFAIK this doesn't affect its strength or properties.
The reasons I like this approach:
- It's easy to remember
- It can be done reliably without looking (in the dark)
- The knot is always under control as you're tying it - so for example this method can be used while walking, even dragging the line behind you, or lying on your back
- You can see the whole process clearly if you want to look at it
Grog's method is a little easier to do, and at least as good for (1) and (4). But (2) and (3) are very important for me - I have a strong preference for knots that can be used in difficult circumstances.
Edited by Gordias, 30 October 2014 - 11:25 AM.