Seamanship Techniques 2011 E Part 3 docx

63Ropework Standard or Plain Laid Standard lay may be described as a cross between hard- and soft-laid ropes. It has been found by experience to be the best in providing pliability and strength, and to be sufficiently hard-wearing and chafe- resistant to suit the industry for general purpose working. Sennet-Laid Alternatively known as plaited, but not as in the way as the ‘eight strand plaited’ previously mentioned, an example of sennet lay is found with the patent log line, where the yarns are interwoven, often about a centre heart. This lay of rope has an effective anti-twist, non-rotational property. Unkinkable Lay This lay looks like standard lay, but close inspection will reveal that the yarns are twisted the same way as the strands. Left-handed in construction, it is usually ordered for a specific job, e.g. gangway falls. The advantage of this lay is that the tendency for standard lay to kink when passing through a block is eliminated. SMALL STUFF Small stuff is a collective term used at sea with respect to small cordage usually less than 1 1 2 in. in circumference and of 12 mm diameter approximately. Hambroline (hamber line) Also known as codline, this is supplied in hanks of about 30 fathoms. It is made of soft tarred hemp, three yarn or three-stranded, laid up right- handed. It is manufactured in two sizes, three or six threads, and is used for lashings where strength is essential, or for lacing sails usually an untarred variety having a hard lay. Houseline Manufactured from Indian hemp, houseline is made of three yarns laid up left-handed. It is tarred and sold in balls by weight and often used to secure bolt rope to sails. Boat Lacing Manufactured in fourteen various sizes, it is made of a high grade dressed hemp, having a fine finish and being smooth to handle. Before the invention of man-made fibre, it was used for securing boat covers, awnings etc. It is sold in hanks weighing from 93 g to 1.8 kg. Marline Marline is usually supplied in hanks by weight, tarred or untarred. It is made in two ply, i.e. two yarns laid up left-handed, from better quality 64 Seamanship Techniques fibres than spunyarn, and produces a much neater, tighter finish to any job. It is used for seizings, serving and whipping heavy duty ropes. Spunyarn Made from any cheap fibres and turned into yarns, spunyarn may have two, three or four yarns, usually laid up left-handed. The yarns are supposed to be soaked in Stockholm tar, for spunyarn is used for the serving of wires, and the idea was that in hot climates the lubricant (Stockholm tar) would not run from the serving. Spunyarn is generally sold in balls of up to 3.2 kg or in coils of 6.4 kg or 25.6 kg by length or weight. Point Line A three-stranded manilla rope, point line is made and may be ordered in three sizes, which are determined by the number of threads: Circumference 1 3 8 in diameter 11 mm 15 threads. Circumference 1 1 2 in diameter 12 mm 18 threads. Circumference 1 5 8 in diameter 13 mm 21 threads. It is used as an all-purpose lashing aboard most present vessels. Sisal very often replaces manilla in so-called point line. Ratline This is one of the family of tarred cordage, measured the same as point line, except that the number of threads may be as high as twenty-four (circ. 1 3 4 in.). It was used in the past for steps between the shrouds of a mast. If seen on a modern vessel, it will probably be encountered as a heaving line. Supplied in coils of 120 fathoms, it is made of three- stranded soft hemp, hawser lay. Logline Logline is made of sennet-laid hemp (plaited), specially for the towing of the rotator (patent log), and comes in 40, 50, 65, or 70 fathom coils. The size will vary from about 3 4 in. to 1 1 2 in. (6–12 mm diameter). The woven line is kink proof, very durable and sometimes built up about a copper wire core. Lead Line Made of high grade cable-laid hemp, it may be obtained in two sizes: 1 1 8 in. (9 mm diameter) for hand lead lines, and 1 1 2 in. (12 mm diameter) for deep sea lead lines. It is supplied in 30 fathom coils for the hand lead, and in 120 fathom coils for the deep sea lead. Seaming Twine Manufactured from the best flax, this three-ply twine is made up in hanks of approximately 1 lb weight and 900 fathoms length. It is used extensively for canvas work. 65Ropework Roping Twine This five-ply twine is supplied in hanks of similar length and weight to that of seaming twine. It is used for whipping the ends of ropes, worming etc. Signal Halyard Often spelt halliard, this used to be three- or four-stranded dressed hemp, but this natural fibre has given way to man-made fibres such as polypropylene. It may be supplied in a variety of sizes to the customer’s requirements. Plaited laid halliards are predominant on the modern merchant vessel, being preferred because the stretch is not as great as, say, hawser lay. The word halyard was derived from the old-fashioned ‘haul yard’, which was previously employed on sailing vessels to trim and set the sails to the yard arms. SYNTHETIC FIBRE ROPES Although natural fibre ropes are still widely used throughout the marine industry, they have been superseded by synthetic fibres for a great many purposes. Not only do the majority of synthetic ropes have greater strength than their natural fibre counterparts, but they are more easily obtainable and at present considerably cheaper. Breaking strain and resistance to deterioration are listed in Tables 3.1 and 3.2. Nylon This is the strongest of all the man-made fibre ropes. It has good elasticity, stretching up to 30 per cent and returning to its original length. It is used for such functions as shock-absorbing when coupled with a mooring wire: the nylon forms a rope tail which takes the heavy shocks as a vessel ranges on her moorings. It is also used in a combination tow line – one section steel wire and one section nylon rope. Nylon ropes are light to handle, twice as strong as an equivalent sized manilla and give the appearance of a smooth slippery surface. They are impervious to water, have a high melting point, 250°C, and in normal temperature are pliable, being suitable for most forms of rigging. The disadvantages of nylon ropes are that they do not float, and in cold climates they tend to stiffen up and become difficult to handle. They should not be left exposed to strong sunlight or be stowed on hot deck surfaces, as their natural life will be impaired. The significant point with these ropes is that they are used when great stress occurs. Should they part under such stress, there is a tendency for them to act like elastic bands, an extremely dangerous condition to be allowed to develop. The nylon rope will give no audible warning when about to part; however, when under excessive stress, the size of the rope will considerably reduce. They are difficult to render on a set of bitts, and should never be allowed to surge. Any splices in the nylon ropes will tend to draw more easily than in natural fibre when under stress. Nylon is expensive, but its life may be considered to be five times as long as its manilla equivalent. Many natural fibre products such as ‘Ratline’ and ‘Hambroline’ have been phased out of common use with modern ship designs and have been superseded by man-made fibre substitutes. 66 Seamanship Techniques Polyester A heavy rope compared to the nylon and not as strong, but nevertheless some of the polyester’s properties make it a worthwhile rope to have aboard. It is considered to be more resistant to acids, oils and organic solvents than its nylon counterpart, while its strength remains the same whether in a dry or wet condition. It is used for mooring tails and mooring ropes. Its disadvantages are very similar to nylon’s. It will not float. Splices must have four full tucks and may draw more easily than with a natural fibre rope when under stress. It should not be surged on drum ends. Frictional heat should be kept to a minimum when working about bitts or warping drums. The melting point is between 230° and 250°C. Polypropylene This is probably the most popular of the man-made fibres at sea. The ropes are cheap, light to handle, have the same strength whether wet or dry, and they float. They are used extensively for mooring ropes and running rigging. The melting point is low compared to nylon, 165°C. Friction-generated heat should be avoided with this man-made fibre, which is extremely susceptible to melting and fusing. Should the fibres fuse together, the rope is permanently damaged and weakened. It is resistant to chemical attack by acids, alkalis and oils, but solvents and bleaching agents may cause deterioration. It neither absorbs nor retains water, and because of this fact has recently been used for the inner core of wire ropes, the advantage being that inner corrosion in the wire is eliminated. However, the wire would still need to be lubricated externally. Fibrefilm, a by-product from polypropylene, is a very cheap version of the fibre. It is produced from continuous thin twisted polypropylene tape, and used for general lashing purposes. Precautions When Handling Synthetic Man-Made Fibre Ropes 1 The mariner should carefully inspect a rope, both internally and externally, before it is used. Man-made fibre ropes show deterioration after excessive wear by a high degree of powdering between the strands. 2. Ropes should be kept out of direct sunlight. When not in use, they should be covered by canvas or other shield, or, if the vessel is engaged on long sea passages, stowed away. 3. When putting a splice in a synthetic fibre rope, use four full tucks, followed by two tapered tucks (strands halved and quartered). The length of the protruding tails from the completed splice should be left at least three rope diameters in length. Any tail ends of strands should be sealed by tape or similar adhesives. 4. A stopper should be of the same material as that of the rope being stoppered off, and should preferably be of the ‘West Country’ type. The one notable exception to this rule is that a nylon stopper should never be applied to a nylon (polyamide) rope. 67Ropework 5. A minimum number of turns should be used when heaving man- made fibre ropes about winch barrels or capstans. Friction-generated heat should be avoided, and to this end no more than three turns should be used on drums. Where whelped drums are being used, it may be necessary to increase the number of turns so as to allow the rope to grip; if this is the case, then these turns should be removed as soon as possible. 6. Never surge on man-made fibre rope. Should it be required to ease the weight off the rope, walk back the barrel or drum end, as when coming back to a stopper. 7. When making fast to bitts, make two round turns about the leading post, or two turns about both posts, before figure-eighting (see Figure 3.3). BENDS AND HITCHES Blackwall Hitch – Single Used as a jamming hitch, this is not in common use at sea today, since it was found unreliable and had a tendency to slip. It is only effective on the larger style of hook with a wide surface area or on the very small jaw hooks (see Figure 3.4). Blackwall Hitch – Double This is used for the same reasons as above but with far more confidence. Holding power is considerably better than that of a single Blackwall, and light hoists could be made with this hitch (see Figure 3.4). Bowline Probably the most common of all hitches in use at sea is the bowline (Figure 3.5). If is by far the best way of making a temporary eye in the end of a rope, whether it be point line or mooring rope size. It will not slip even when wet, it will not jam, and it will come adrift easily when no longer required. It is commonly used to secure a heaving line to the eye of a mooring rope when running a line ashore. Bowline on the Bight This is one of several variants of the bowline, made with the bight of the rope, so forming two eyes (Figure 3.5). One of these eyes should be made larger than the other to accommodate the seat, while the smaller of the two eyes would take the weight under the arms of an injured person. It forms a temporary bosun’s chair for lifting or lowering an injured person. It may be necessary to protect the person from rope burn or pressure by padding under the seat and armpits. Bowline – Running A slip knot is made by dipping the bight of rope around the standing Figure 3.3 Making fast to bitts. Figure 3.4 Single Blackwall hitch (left) and double (right). 68 Seamanship Techniques 12 3 Figure 3.5 Bowline (top), bowline on the bight (middle) and running bowline (bottom). part and securing an ordinary bowline on to its own part, so forming a running noose (Figure 3.5). It should be noted that it is a common mistake for inexperienced seafarers to assume that the tail end of rope can be passed through the eye of an ordinary bowline. This is not only inaccurate but time-consuming, especially if the length of the rope is considerable, as with a full coil. Bowline – French An alternative to the bowline on the bight, this hitch has the same function of allowing the weight of a man to be taken up by the two eyes (see Figure 3.6). Carrick Bend – Single Originally used for bending two hawsers around a capstan, the bend was constructed so that it formed a round knot which it was thought would not become jammed in the whelps of the capstan barrel. It is a strong versatile bend that will not jam under strain, providing it is properly secured (Figure 3.7). The idea of the knot is for the weight to be taken on either side; the bend should be seen to hold, and only then should the tail ends be seized to the standing parts. It is often thought that the ends should be seized Goose neck Armpit bight Seat bight Figure 3.6 French bowline. 69Ropework immediately after securing the bend, but this is not the case; weight must first be taken and the bend will be seen to slip and close up on itself; only after this has occurred should the ends be seized. Carrick Bend – Double This version of the carrick bend (Figure 3.7) is formed in a similar manner, except that a round turn is made about the cross of the first hawser. It is used where additional weight could be expected to bear, as in towing operations. Again the tails should be left sufficiently long so that, when the weight is taken up and the bend slips to close itself, there will be enough slack in the two tails left to seize down to the standing part. The advantage of this bend over a sheetbend is that it will easily come adrift when no longer required, whereas the sheetbend may jam and have to be cut away. Carrick Bend – (Single) Diamond So called because of the diamond shape formed in the middle of the bend, prior to taking weight on the two hawsers either side, it only differs from the single carrick in the fact that the tail end is not seized on the same side as in the single carrick, thus giving the appearance of being a different version of the single carrick. It is used for exactly the same purposes as above, and forms the basis for many fancy ropework knots (see Figure 3.7). ‘Catspaw’ This is used to shorten a bale sling strop and is constructed by using two bights of the strop. Two eyes are formed by simply twisting each bight against itself, the same number of twist turns being applied to each bight. The two eyes so formed can then be secured to a lifting hook or joined by a securing shackle (see Figure 3.8). The stevedore’s method of ‘shortening a strop’ (Figure 3.9) is an alternative to the ‘catspaw’. It is achieved by passing opposing bights of the strop through their own parts, effectively making an overhand knot with the bights. Clove Hitch A very common hitch in use at sea today, it consists of two half hitches jamming against each other. It is a useful knot for turning about a rail and hanging things from, but unreliable, especially when the direction of weight is liable to change; that could easily cause it to slip (see Figure 3.8). Cow Hitch This hitch is used to form the ‘bale hitch’ when employing a bale sling strop. It is, however, more commonly used to hold a wire rope when constructing a chain stopper (see Figure 3.8). Seizing Seizing Seizing Figure 3.7 Carrick bends: single (top), double (middle) and diamond (bottom). ‘Cow hitch’ ‘Catspaw’ Figure eight knot Marline spike hitch Clove hitch Figure 3.8 70 Seamanship Techniques Figure Eight Knot Used as a stopper knot and employed in many forms, especially at sea, it can regularly be found in the lifelines of ships’ lifeboats and in the keel grablines of boats’ rigging. It is also used to secure the logline to the frog and patent rotator. An all-purpose knot, it prevents a rope from running through a block (see Figure 3.8). Fisherman’s Bend This is used for securing a hawser to the ring of a buoy. The bend differs from the round turn and two half hitches, for the first half hitch is passed through the round turn. The second half hitch is not always applied, but, in any event, with both the round turn and two half hitches and the fishermans bend, the tail end of the securing should always be seized down to the standing part (see Figure 3.11). Marline Spike Hitch An easily constructed hitch (Figure 3.8) much used by riggers to gain more leverage when gripping thin line or rope. It is useful when whipping or binding is required to be drawn exceptional tight. Midshipman’s Hitch This hitch may be used instead of a Blackwall hitch, especially when the rope being used is ‘greasy’. It is a quick method of securing a rope’s length to a hook (see Figure 3.12). Reef Knot This is basically a flat knot, ideal for securing bandages over a wound when tending injured personnel; the flat knot lies comfortably against the patient without aggravation. It is also employed in boat work, for the purpose of reefing sails (see Figure 3.13). Rolling Hitch The rolling hitch is one of the most useful hitches employed at sea (Figure 3.10). Providing it is properly secured and the weight is against the double bight turn, the hitch should not slip. As it is a secure hitch, it is used to secure the jib halyard block to the sea anchor hawser, when rigging a whip for use with the oil bag from a lifeboat. Old sailors used to secure their hammocks by use of a rolling hitch. This prevented the hammock from sliding to and fro with the motion of the vessel when in a seaway. Round Turn and Two Half Hitches This all-purpose hitch is used to secure a rope or hawser to a ring or spar, e.g. to secure the tail block of a breeches buoy rig. It is useful in the fact that by removing the two half hitches, the weight on the rope can still be retained and eased out by slipping the round turn. An example of this Figure 3.9 Stevedore’s method of ‘shortening a strop’. 123 Figure 3.12 Midshipman’s hitch. 12 3 Figure 3.11 Fisherman’s bend. Rolling hitch Timber hitch Figure 3.10 Rolling hitch (above), timber hitch (below). 71Ropework in action is seen when ‘bowsing in’ tackles are employed in launching ships’ lifeboats (see Figure 3.14). Sheepshank The sheepshank (Figure 3.15) is used generally for shortening a rope without cutting its length. It is often used in keel grablines under ships’ lifeboats, and may also be employed to adjust the length of a boat’s painter when the boat is tied alongside in tidal waters, as the tide rises or falls. Sheetbend – Single This hitch is commonly used (Figure 3.16) to join two ropes of unequal thickness. However, when employed for this purpose, there is a tendency for it to ‘jam up’ after weight has been taken on the standing part. A carrick bend would be more suitable when weight, such as that consequent upon a towing operation, is expected. Sheetbend – Double This is used extensively when security over and above that which could be expected when employing a single sheetbend is required. It is used whenever human life needs safeguarding, for example when securing a bosun’s chair to a gantline (see Figure 3.16). Timber Hitch A slip knot, in common use at sea today, the timber hitch (Figure 3.10) lends itself to gripping a smooth surface like a spar or log. It is often used in conjunction with a half hitch. It may also be used for lifting light cases or bales, but the mariner should be aware that it is a slip knot, and once the weight comes off it, there would be a tendency for the hitch to loose itself. Barrel Slings See Figures 3.17 and 3.18. WORKING ALOFT AND OVERSIDE Rigging the Bosun’s Chair See Figure 3.19. Close inspection should be made of the chair itself and the gantline before the chair is used. The gantline should be seen to be in good condition, and if any doubt exists, a new rope should be broken out. The bridle to the chair should be inspected, and particular attention paid to the internal lay and its condition. A safety line with safety harness must always be worn when operating from a bosun’s chair. This line should also be inspected before use, then secured to a separate anchor point. When working from a bosun’s chair, the following precautions should be observed: 1. Always secure the gantline to the chair with a double sheet bend. 2. Always have the chair hoisted manually, and never heave away on the down haul using a winch drum end. Figure 3.13 Reef knot. 12 3 Figure 3.14 Round turn and two half hitches. Figure 3.16 Single and double sheetbends. 12 3 123 Seizing Toggle Figure 3.15 Sheepshank (above) and securing the sheepshank (below). 72 Seamanship Techniques 12 3 Moused hook Reef knot 4 1 2 3 Use of a bale sling strop Butt sling Figure 3.17 Single barrel sling. 1. Pass bight under the cask and secure with an overhand knot above the open end of the cask. 2. Open up the overhand knot. 3. Take the weight on either side of the cask. 4. Secure both tails with a reef knot. Ensure that the reef knot is secured low to the top end of the cask, to allow the full weight to be taken on the standing part. Figure 3.18 Double barrel sling. 1. Pass the bight under the cask. 2. Pass open half hitch over the cask with each tail. 3. Tension each tail and secure with reef knot as for single barrel hitch. (Below) Slinging a cask on its side. 3. Any tools, paint pots etc. should be secured by lanyards. Any loose articles should be removed to prevent falling when aloft. 4. When riding a stay, make sure the bolt of the bow shackle passes through the becket of the bridle. This bolt should be moused. 5. Should work be required about the funnels, aerials, radar scanners and the like, the appropriate authority should be informed – engine room, radio officer or Bridge respectively. [...]... sheaves Sheaves Examine for cracks in the metal and check that the bush is not slack in the sheave or causing excessive wear on the axle pin Each sheave should be seen to turn freely by hand Sheaves worn in the groove could cause excessive ropewear and should be checked whenever a new rope is to be rove Axle pins Check axle pins for wear, and ensure that they do not rotate They should be securely held... a fibre rope, then the fibre rope should be fitted with a thimble, so preventing chafe and wear about the eye Wire ropes should never be led across fibre ropes and allowed to cause chafe Chain stoppers should be used on wire ropes Wire on drum ends should not be used as check wires Should a wire rope be used as a slip wire, then the parts of the eye should be seized together and reduced in size to allow... However, all wire ropes are affected by wear and bending, especially so when the ropes are operated around drum ends or sheaves Resistance to bending fatigue and to abrasion require two different types of rope Maximum resistance to bending fatigue is obtained from a flexible rope with small outer wires, whereas maximum resistance to abrasion needs a less flexible rope with larger outer wires When selecting... suitable strength and size, with an eye in one end Pass the seizing about the two ropes, threading the end through the ready-made eye Use figure of eight turns between the two ropes for up to ten or twelve turns, then pass riding turns over the whole between the figure of eight turns Once the riding turns are completed, the seizing should be finished by passing frapping turns between the two ropes, and securing... the coil from the outside and working inwards to the centre (see Figure 3. 33) (i) Opening a new coil of small rope Swivel (ii) Opening a new coil of large rope Figure 3. 33 Breaking out a mooring rope 4 WIREWORK AND RIGGING STEEL WIRE ROPE A steel wire rope is composed of three parts – wires, strands and the heart The heart is made of natural fibre, though recently synthetic fibre has been used when... on, and use a sailmaker’s needle to stitch the underside of the two whippings The stitches, made in sail twine, must be drawn very taut to keep up the pressure between the rope ends If the operation is being carried out on wires, then seizing wire would be used in place of sailmaker’s twine Before joining wires in this manner, ensure that the ends of the wires are securely whipped and that the whippings... designed to accommmodate the size of wire (Figure 4.16) Often the reels are equipped with a gearing ratio to allow easier manual operation; and, strictly speaking, if the reel is geared, it is a winch in the true sense of the word However, it is common practice for seamen to refer to geared or ungeared drums simply as reels The wire should never be shackled to a reel, as this practice would prove extremely... purpose of serving the wire eye splice The underside of the board has a similar groove to that of the serving mallet, except that the groove is ‘flatter’ and more open, to accommodate the broad eye of the wire rope where it has been spliced Serving Mallet This wooden mallet, cut with a deep-set groove running the full length of the hammer head, is used to turn the serving (marline or spunyarn) about the... polyester The stopper should be flexible Never use nylon stoppers on nylon ropes (polyamide) The size of the rope for the stopper will vary with the type of stopper being applied, either common or West Country In the case of the West Country stopper the size of the rope should be as near as possible to 50 per cent breaking strain of the rope it is being applied to.Table 3. 3 shows sizes for the West... be seized securely together If a thimble is to be inserted, so making a hard eye, then this should be placed inside the bight of the eye before applying the seizing The thimble is secured in position by light seizings, about the crown and shoulders of the thimble (Figure 4.14) The end of the wire should then be unlaid, exposing the heart Each tail unlaid should be whipped at the end to prevent the . the bowline, made with the bight of the rope, so forming two eyes (Figure 3. 5). One of these eyes should be made larger than the other to accommodate the seat, while the smaller of the two eyes. ordered in three sizes, which are determined by the number of threads: Circumference 1 3 8 in diameter 11 mm 15 threads. Circumference 1 1 2 in diameter 12 mm 18 threads. Circumference. properly secured (Figure 3. 7). The idea of the knot is for the weight to be taken on either side; the bend should be seen to hold, and only then should the tail ends be seized to the standing parts.