This 'Alpine Butterfly' article is part of the book - The Trad Climber's Guide To Problem Solving.
The alpine butterfly knot is used for:
- Equalizing a two-bolt belay.
- Isolating a damaged section of rope.
- Forming a fixed loop in the middle of a rope. This provides a clip-in point which can be loaded in 2 or 3 directions.
How To Tie an Alpine Butterfly Knot
Form a loop in the rope.
Twist the loop so it becomes two loops. Then pull the top of the upper loop behind and underneath the line of the rope.
Push the now lower loop through the original first loop.
Pull it tight.
You should end up with this:
An alternative way to tie the alpine butterfly is to wrap it around your hand three times as shown below. Pull the top wrap down over the other two, then back up behind them.
Using the Alpine Butterfly Knot
Equalizing a Two-Bolt Belay
Tie a large-looped alpine butterfly to one screwgate and a clovehitch to the other.
You can adjust the size of the loop once the alpine butterfly is tied. Then adjust the clovehitch to fine tune the equalization.
This is useful for fixing ropes, such as on a big wall.
Isolating a Damaged Section
This is useful when using your rope as a fixed line or in a situation where the rope will not pass through any carabiners.
Obviously, you will not be able to lead climb with a knot in your rope!