Download
1 / 25
260 likes | 436 Vues
Knot Tying in Rigging Applications. Presented by: Christopher G. Lombard ACED 4680. Overview. Throughout history, ever since humankind invented rope, skill in tying knots and the development of rope has played a vital role in early technological advancements and the building of civilizations.
E N D
Knot Tying in Rigging Applications Presented by: Christopher G. Lombard ACED 4680
Overview • Throughout history, ever since humankind invented rope, skill in tying knots and the development of rope has played a vital role in early technological advancements and the building of civilizations. • Although it is still unclear when the first rope was made, evidence suggests that it was during prehistoric times. • This is due to the fact that the first rope was made of natural fibers that decomposed and did not survive the ages. • The first ‘ropes’ were formed from naturally occurring plant stems, such as lengths of vine.
Overview • In order for rope to be useful, our early ancestors had to develop some level of skill in tying knots. • Fragments of rope have been discovered and dated back to approximately 15,000 BC. • The early Egyptians were the first civilization to develop tools designed for rope manufacture and, thusly, have been credited with first mastering large-scale rope production. • Such ancient and rudimentary skills have seldom transcended the ages, however knot tying is one that remains pertinent to this day…
Knowledge and learning objectives • Upon successful completion of this topic the student will be able to: • Recall at least three of the four methods of preventing a rope from unlaying, as presented in the instructional materials. • Recite the meanings and definitions of at least eight of the twelve terms presented in the instructional materials. • Visually identify the five knots commonly utilized in rigging applications, as presented during instruction, with no errors.
Knowledge and learning objectives • Recall seven of the ten basic categories and different types of fiber used to manufacture rope as presented in the instruction and course materials. • As presented in the course materials and instruction, name the two primary types of rope with no errors. • Demonstrate ability to tie a bowline in the same manner as illustrated and performed during the course of instruction with no errors. • Demonstrate ability to tie a square knot in the same manner as illustrated and performed during the course of instruction with no errors.
Knowledge and learning objectives • Demonstrate ability to tie a figure eight knot in the same manner as illustrated and performed during the course of instruction with no errors. • As illustrated and performed during the course of instruction, demonstrate ability to tie a clove hitch sufficient to prevent untying of the knot when a pull is applied to the line with no errors. • Demonstrate the ability to ascertain and tie the safest knot under a specified application to assure that a load will be held most securely with no errors. • Recall the proper technique for backing a knot to prevent its loosening or unraveling with no errors.
Terminology • In order to understand some uncommon and trade specific terms, we must review them: • Back – to reinforce a knot, bend, or hitch with another. • Bight – a pinch point or loop in a rope. • Bitter end – the end of a rope. • Coefficient of friction - a ratio between the force required to move one surface over another and the pressure exerted between them. • Efficiency rating – the efficiency of a knot, expressed as a percentage, as it relates to breaking strength.
Terminology • Filament– fiber or a slender threadlike object. • Frap – to bind something tightly. • Fray – to become worn at the end or edges or unravel into separate filaments. • Knot - intertwined loops of rope used to fasten one to another or to some other object. • Strand – several filaments or fibers that are twisted, woven, or bundled together. • Tail – a short portion of a rope adjacent to the bitter end. • Unlay – untwist into the separate strands.
Categories of rope • Categories of rope: • Natural fiber • Examples are rope produced from jute, sisal, hemp, manila, and cotton. • Synthetic fiber • Examples are nylon, polypropylene, and polyester.
Types of rope • Types of rope used in rigging applications: • Three strand – rope consisting of three intertwined strands. • Double braid – rope constructed of multiple strands woven together.
rope characteristics • With regards to knot tying and rigging, there are important advantages, disadvantages, and differences between rope types that must be considered: • Breaking strength (synthetics have edge) • Suppleness/pliability (nylon, polyester, and cotton best) • Coefficient of friction (natural slightly better) • Durability (fairly even) • As you can see, there is a fairly even split between natural and synthetic. Selection is dependent upon application and desirable characteristics.
preventing unlaying • Methods of preventing a bitter end from unlaying: • Taping or shrink wrapping (natural and synthetics) • Heat treating (synthetics) • Frapping or binding (primarily used on natural rope) • Tying a knot
Tying with a rope • There are three basic ways to tie or bind using a rope: • Knot - intertwined loops of rope used to fasten one to another or to some other object. • Bend – an intertwining of two rope ends. • Hitch – attaching a rope to a post, ring, or other, usually round, object. • Efficiency ratings of knots, bends, and hitches generally fall between 50 – 75%.
primary rigging Knots • There is a combination of five knots and hitches that are used most often in rigging applications: • Bowline (knot) • Square knot • Clove hitch • Half hitch • Figure eight (knot)
BOWLINe Purpose/application: whenever a loop is required Advantages: will not bind/cinch under strain, unties easily Efficiency: 50%
Square knot Purpose/application: attaching the ends of ropes together Advantages: quick to tie once proficient, not prone to loosening Efficiency: 50%
CLOVE HITCH Purpose/application: attaching a rope to poles, rings or other round objects Advantages: self cinching, easily tied/untied, high efficiency Efficiency: 75%
half HITCH Purpose/application: used to hold a line, keep long objects upright, back up other knots/bends/hitches Advantages: very easily tied/untied, self cinching, high efficiency rating Efficiency: 70% The Half Hitch
Figure Eight Purpose/application: used to tie down/secure objects, prevent rope from unlaying Advantages: easily tied, self cinching under strain Efficiency: 50%
SUMMARY Categories of rope (2): Natural Synthetic Types of rope (2): Three strand Double braid Important rope properties/characteristics (4): Breaking strength Suppleness/pliability Coefficient of friction Durability
SUMMARY • Basic ways to tie or bind using a rope (3): • Knot - intertwined loops of rope used to fasten one to another or to some other object. • Bend – an intertwining of the ends of two different ropes. • Hitch – attaching a rope to a post, ring, or other, usually round, object. • Methods to prevent unlaying (4): • Taping or shrink wrapping (natural and synthetics) • Heat treating (synthetics) • Frapping or binding (primarily used on natural rope) • Tying a knot
Review Associate the knots pictured with their names: Square knot Bowline Half hitch Figure eight Clove hitch A B C E D
RESOURCES/REFERENCES • http://listverse.com/2007/10/07/top-10-ancient-inventions/ • http://www.igkt.net/beginners/what.php • http://www.2020site.org/knots/ • http://www.animatedknots.com/indexbasics.php?Categ=basics&LogoImage=LogoGrog.jpg&Website=www.animatedknots.com • All Images sourced from Google Images.
conclusion Questions?
