Thursday, March 19, 2015

Knots - Handcuff knot

Introduction

Finished handcuff knot
Handcuff knot

As the name implies, the handcuff knot can be used to bind the hands or feet of your adversary. It is also known as a "hobble knot".  It isn't very practical but it is sure fun! It is a Slip Loop type of knot.

With my Scout group this knot is always the first one that I teach when I am introducing knots because it is easy to make a game of it. It gets them interested in the subject of knots (which can be a challenge). What kid doesn't want to capture a friend with handcuffs as part of a cops and robbers game?


Tying the knot

Animated handcuff knot


  1. First, make a butterfly shape with your hands, with the rope hanging across the middle of the thumbs
  2. Slide your hands apart a bit
  3. With your right hand fingers, pick up the rope on the left hand and pull it up and through. Keep the bight of rope between your fingers!
  4. With your left hand fingers, pick up the rope on the right hand and pull it up and through. Keep the bight of rope between your fingers!
  5. Now finally, pull the two bites apart and let the loops form in the rope.
  6. Hold the two working ends tight so that the handcuff stays tight. 
The knot can be locked by tying a half hitches around each of the loops using the working ends. This is also referred to as a "Fireman's chair knot".

The game

The game that we played with the handcuff knot is basically a modified version of freeze-tag. The object is to capture all of the "robbers" as quickly as they can. 

Pick a few kids to be the "police" and give them rope (approximately 1m long).  The police need to tag a robber and then the robber has to freeze for the count of 5 seconds. If the police can't tie the knot in 5 seconds the robber gets away and the police need to untie the rope and start again.If the robber is captured they are out until the end of the game.



As the kids get better at tying the knot you can reduce the number of seconds they have. Believe me, they will get very quick at it!

Knots - Bowline

Source: http://www.animatedknots.com/bowline/


The bowline is one of the most basic sailing knots and is almost universally used for attaching sheets to sails. It is generally useful in situations where a loop is needed in the end of a rope. It can be tied by itself or around an object.

It is normally the 3rd knot that we teach our scouts (behind the handcuff and square). I have used it extensively camping and in many ways around the house. 

The bowline is highly reliable, except with slippery rope. Poor quality nylon rope tends to slip and come apart. 

Tying

The mnemonic for tying the bowline is:
"The rabbit comes up through the hole, around the tree and back down the hole." 

The basic steps are:
  1. Create a bight in the rope (around an object if desired)
  2. Create a loop in the standing end of the rope
  3. Put the working end through the loop
  4. Bring the working end around the standing end
  5. Bring the working end back through the loop
  6. Tighten




Knots - Figure-eight


Regular Figure-eight


The figure eight knot is a foundation knot that is useful in many situations. In its primary form it is simply a stopper knot. IE, a knot that creates a stopping point in the rope when it is travelling through a hole of some sort. 

In sailing, a figure-eight is often used at the end of a line (for example a jib sheet) to keep it from escaping through its block (pulley). It is used similarly in rock climbing.
Source: http://www.boatus.com/

While many knots are known to cause a degradation in the strength of the rope that it is tied in, the figure-eight fairs pretty well in this respect. It causes a reduction of 20% from the original breaking strength.


Tying the knot

Animated figure-eight
Animated Figure-Eight
  1. Make a "loop" by crossing the working end over the standing end
  2. Continue the working end around the standing end a full turn to make an "elbow"
  3. Bring the working end back up through the loop
  4. Tighten as needed

"Figure-eight on a bight"

The figure-eight on a bight is used any time that you need a strong loop tied in a rope and it doesn't need to be adjusted regularly. The figure-eight on a bight is strong and easy to tie.

Source: http://www.canyoneeringusa.com/

Tying the knot

Use the exact same technique as above. However, before you start, double the rope back on itself to create a loop. Treat the loop as if it was a single rope and tie the figure-eight as you did before. You will be left with a loop in the end.

"Figure-eight follow through"


The "figure-eight follow through" is a form of the figure-eight that is often used in rock climbing as a way to tie into the the harness since it is:
  • Easy to tie
  • Easy to verify that it is tied correctly
  • Doesn't reduce the strength of the rope considerably
  • Doesn't slip
Once tied it is identical to a "figure-eight on a bight" (above) but is tied differently because it is often used around a closed object (like the anchor ring on a harness)

Tying the knot



  1. Start with a figure-eight tied at least 30cm up the working end of the rope
  2. Bring your working end around whatever object the rope needs to be fastened to
  3. Feed the working end back into the top of the figure-eight
  4. Follow the exact same path backwards through the knot. Make sure that you keep the working end tightly following the existing knot path. 
  5. Exit the knot through the standing end side of the knot
  6. Tighten
  7. Lock with half hitches, if required
Animated Figure-eight follow through
Animated Figure-eight follow through