Knots: Difference between revisions
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== Prusiks == | |||
A great online resource showing how to tye different types of Prusik knots including explanations of Pros and Cons of each | |||
[https://www.vdiffclimbing.com/prusik-types/ Prusiks] | |||
== Technical Information == | |||
Lots of info here | |||
Pay special attention to the heat resistant properties of the synthetic fibre ropes *particularly Dyneema | |||
[https://www.gleistein.com/en/ Gleinstein Ropes] | |||
== Strength of Knots == | |||
*This is generalisation. Strength with vary slightly depending on the rope material | |||
{| class="wikitable" | |||
|- | |||
|- | |||
|Overhand Knot | |||
|Figure of Eight Knot | |||
|Reef or Square Knot | |||
|Sheet Bend | |||
|Bowline Knot | |||
|Clove Hitch | |||
|Fisherman’s Knot | |||
|Fisherman’s Bend | |||
|Two Half Hitches | |||
|Timber Hitch | |||
|Short Splice | |||
|Eye Splice | |||
|- | |||
|45% | |||
|45% | |||
|50% | |||
|50% | |||
|60% | |||
|60% | |||
|65% | |||
|65% | |||
|65% | |||
|70% | |||
|90% | |||
|95% | |||
|} |
Latest revision as of 11:34, 8 April 2021
Knots
The only knots that I ask students to learn during first term are the Reef Knot, Bowline Clove Hitch, Sheet Bend and Figure of Eight loop. During the following terms you will hopefully wish to return to Technical Stage Management and will learn more advanced knots such as the Alpine Butterfly, Truckers Hitch, Highwayman’s Hitch, Fisherman’s Bend, Sheep Shank, Rolling Hitch etc. Each of these knots has a specific purpose, so therefore simply knowing how to tie a knot is only half the requirement. Knowing when to use the knot is equally, if not more, important.
Parts of a rope
The Working End or Running End of a rope is the part used in tying the knot.
The Standing Part is the whole of the rest of the rope i.e. the part not used in tying the knot.
The Standing End is a short region at the end of the Standing Part.
The Bight is the region extending all the way from the Standing End to the Running End. Therefore a knot which is tied “in the bight” is one which is tied without using either end. The Bight can also mean a loop made without use of the working end, as in the diagram earlier in the section showing how to coil a rope. “Push a bight through the gap as shown above then fold it back over the top of the coil”
A Knot is anything deliberately tied in a rope.
A Bend is a knot for joining two ropes.
A Hitch is a knot for joining a rope to a support.
The Reef Knot
Make a half-knot, starting left over right (top picture) then add the second half-knot right over left. To confirm, check that, on each side the two ends pass each other both above or below the part that crosses them.
The Reef Knot, or Square Knot as it is sometimes known, is not a particularly safe knot and should never be used when lifting weight. It is extremely unsafe joining ropes of different thickness. Its use in the theatre is limited to temporarily joining two ends of a rope, which is not to be taking weight. It’s a simple and easy to tie knot with limited use, learn to tie this first as dexterity practice and an introduction of how knots work.
The Clove Hitch
There are a couple of different ways to tie this versatile hitch which we will discuss in the practical class. One instance where this hitch is used in the New Athenaeum Theatre is to tie the “hemp lines” to the aluminium bars. I would advocate hitching the end to the standing part with a half hitch for security.
The Bowline
Below is a brief description and diagram of a method of tying a bowline. It is a little childish but easier to explain than my usual method of tying. We will discuss and try other methods of tying the knot in the practical class.
First make the half hitch, the rabbits burrow. The rabbit comes out of the hole, runs round the tree, then dives back down the hole.
It should be remembered that with synthetic materials the Bowline is not completely reliable, and in circumstances where failure means disaster, such as weight above actors and technicians heads a stopper knot should be made in the free end (as recommended by the British Mountaineering Council).
At RSAMD we do not use bowlines when we use synthetic rope. A figure of eight loop or a figure of 9 knot should be used instead.
The Figure of Eight Loop
Another loop knot alternative to the Bowline is the figure of eight loop. One of the main advantages the Figure of 8 Loop has over the Bowline is that it very easy to tie and, importantly, very easy see when the knot has been tied correctly. Many people, when they begin to learn knots are unsure if they have tied the knot correctly, and the figure of eight knot is easy to tell if it has been tied correctly. When we are in the business of suspending loads above people’s heads we must always be 100% sure our knots are correct and safe. We are now using this knot instead of the bowline in most rigging so please make sure you are familiar with it.
Before the diagram of the Figure of Eight Loop, here is the simple Figure of Eight Knot. This knot is primarily a stopper knot and therefore not used as much in our day to day rigging in theatre. However you must learn to tie this knot comfortably before you try to tie the Figure of Eight Loop.
Figure of 8 Knot
Figure of Eight Loop
The Figure of Eight Loop is tied exactly the same way as the simple Figure of Eight Knot. The only difference is that we are tying the knot in the bight of the rope instead of the end. You will be shown two methods of tying this knot, you must learn both methods.
Sheet Bend
The final compulsory knot for first years is the Sheet Bend. This knot is used for joining two lines together or even joining a line to a loop of some kind. It is very versatile in that it can join two ropes of different thickness and composition together effectively. This is especially useful to us when picking up hemp lines with sash cord. *Remember to make the loop out of the larger diameter rope when tying different diameter ropes together
Double Fisherman's Knot
A great knot for joining two ropes together is the Double Fisherman's Knot. It's especially good for how adjustable it is, as it is basically two slipknots that pull together, so you can make knot as far up the ropes as you like and pull them down to meet each other. I feel this is a very safe knot to use, however if you're looking for ease of release, it's slightly more difficult to take out than a knot like the Sheet Bend.
Prusiks
A great online resource showing how to tye different types of Prusik knots including explanations of Pros and Cons of each
Technical Information
Lots of info here
Pay special attention to the heat resistant properties of the synthetic fibre ropes *particularly Dyneema
Strength of Knots
- This is generalisation. Strength with vary slightly depending on the rope material
Overhand Knot | Figure of Eight Knot | Reef or Square Knot | Sheet Bend | Bowline Knot | Clove Hitch | Fisherman’s Knot | Fisherman’s Bend | Two Half Hitches | Timber Hitch | Short Splice | Eye Splice |
45% | 45% | 50% | 50% | 60% | 60% | 65% | 65% | 65% | 70% | 90% | 95% |