Rigging - SOIC

Rigging

The Swedish Ship “Götheborg" is a three-masted ship with square sails on all three masts. The mainmast and the foremast have topgallant sails, topsails and courses. The aftermast has a mizzen topsail and a lateen mizzen sail. In the bow is the bowsprit with a jib boom, and hanging below that are two more square sails: the spritsail and the spritsail topsail. A ship of this kind used to be called a frigate rigged ship, although we now refer to it as a fullrigged ship. The 18th century East Indiamen were mainly designed to sail with favourable winds from a stern. The rig carefully reconstructs the original masts, rigging and sails of an East Indiaman from the mid-18th century. The rig is the distinctive arrangement the sails, masts and other spars - i.e. yards, bowsprit and sprit - as well as sails, blocks and ropes. After the “Götheborg" sank in 1745, a list was made of the rigging materials salvaged from the wreck that could be reused. This information provided a partial picture of the rigging, but in order to design the rig for a new ship, better data was required. The dimensions of the rigging have been based on regulations dating from 1730 issued by Tomas Rajalin - Admiral and Head of the Navy´s shipyard in Karlskrona - along with regulations issued in 1797 by Carl Pihlström, ensign and later sub lieutenant. The latter regulations are entitled “Document regarding the proportioning of furniture, in complexity and length, as well as the most important aspects of manufacture". These two sets of regulations were both used in the 18th century when dimensioning trading vessels and men-of-war in Sweden. The regulations were analysed, and the results of this process were entered in a technical design database. Below is an example of an edited excerpt from Rajalin´s regulations entitled “Important information about shipbuilding and essential items and ship systems deriving from that, as well as furniture in proportions according to the orders of the authorities concerned": "The length of the mainmast can be ascertained by adding the ship´s length between prow and stern to 1⁄4 and 1/8 of the ship´s length between prow and stern. 5/11 of that total constitutes the full length of the mainmast.

When the widest beam is greater than 1⁄4 of the ship´s length between prow and stern, the difference between 1⁄4 of the length between prow and stern and the widest beam is added to the mast´s length. If the widest beam is less than 1⁄4 of the length between prow and stern, the difference is deducted instead. If the depth of the room is greater than 1/8 of the ship´s length between prow and stern, the difference s added to the mast´s length. If the depth is less than 1/8 of the ship´s length between prow and stern, the difference is instead deducted from the mast´s length. "Planning work for the rig began at the start of 1999. One of the aims has been to use 18th century materials and building techniques. The Rig Manager is Björn Ahlander, while Jens Langert has been responsible for technical design of the rig. By building an exact model of the hull and rig, it was possible at an early stage to avoid expensive and unnecessary mistakes. The 1:20 scale model was built in close cooperation with the technical designer. On the basis of this model, it was possible to study the standing and running rigging as well as how the sails worked. With the aid of Chalmers University of Technology and the Swedish National Shipbuilding and Ship Research Institute´s test facility, it was then possible to calculate loads and stresses in the masts and rigging. The calculations are based in part on model trials in wind tunnels and wave tanks. Stresses arise due to the wind´s pressure and the ship´s movements in the sea. It is important for the rig that the ship has the correct ballast, as this allows the ship to move gently and ﬂexibly in the sea. When a ship is too rigid it moves jerkily and this places considerable strain on the entire rig. When reconstructing the masts, rigging and sails, it was clear to see the demands the original crews faced. Setting out on the world´s oceans to visit different parts of the globe was a risky adventure. Ships were built bigger and bigger, and required increasingly large rigs. However, the techniques for operating the rig-ging did not develop quite as quickly. That the rig worked at all is down to the

Bernt Sjögren is working with the sails. Click on the image to enlarge.

size of the crews and their skill. Nowadays we can only admire the seamanship of the original crews. At the time when the Swedish East India Company was established, around 500 ships were sailing internationally under the Swedish ﬂag. Most of these were small, however, with not even ten per cent having a loading capacity of 245 tonnes, so they were not suitable for transoceanic travel. In terms of size, the East Indiamen were equivalent to the largest men-of-war of the day, the battleships. However, the crews on the men-of-war were much larger, due to the need to be able to operate cannon effectively in a battle. A Swedish battleship had a crew of 500-700 men, while a Swedish East Indiaman usually had around 100-150 men on board. On one occasion, in 1803-1805, the Swedish East India Company used a man-of-war, the battle-ship “Wasa", for the voyage to Canton. The crew was cut from 556 men to 167 men for this journey. The same materials, dimensions and methods have been used at Terra Nova in Göteborg as were used when rigging East Indiamen in the mid-1700s. Terra Nova´s craftsmen have made a point of ensuring that the production has been essentially carried out manually and using tools faithful to those used at the time. Over two autumns, it was necessary to walk for many miles through forests, accompanied by forest oﬃcers and various forest owners, to ﬁnd the 50 majestic pines required for the large masts and the bowsprit. When selecting the timber, particular emphasis was placed on ensuring that it was growing straight, as free from knots as possible and without loose brushwood.

It should also have tight concentric annual rings. All the trees were felled during the winter months and manually debarked at Terra Nova. The debarking process had to be completed before the trees were attacked by bark beetles in the spring. After that, the logs were sawn according to drawings for beams and other mast parts, and were air dried for up to two years before they could be ﬁnally joined.

The mast workshop at Terra Nova was inaugurated after the summer of 2001. The shipyard´s carpenters were responsible for the production of the yards and building the masts. The mainmast, foremast and bowsprit required much more than a single tree trunk each. The mainmast, with a diameter of 76 centimetres at the deck and a length of 25 metres, was built up of beams from 18 large pines. The beams were ﬁtted together with sawn out pins and recesses, with millimetre precision. The mast is held together with cold shrunk iron rings and rope lashings. This method came into use as the ships grew increasingly large and a single tree was no longer suffcient. A great deal of effort has been invested at Terra Nova in order to employ the same principles today.The bowsprit was made in more or less the same way. It is more than 17 metres long and comprises seven beams, one of which is a hex-agonal centre section. This also required millimetre precision. Masts and poles - vertical spars - have been made from Scots pine (Pinus sylvestris), which is strong and offers good resistance to decay. Yards and spars (horizontal spars) have been made from Norway spruce (Picea abies), which is light and ﬂexible.Larger yards are made from two

large spruce trees, joined with the butt-ends together. Joining beams to make masts and yards is a complex art, which kept the carpenters busy for months. Numerous strength tests and tests to ascertain the correct construction methods were required.

In June 2003, the 23 metre foremast weighing seven tonnes was lifted into place by a mobile crane - in the 18th century, all shipyards had an enormous, manually operated derrick crane for such operations. The mast had been rigged with trestletrees, shrouds, stays, crow´s nest and mast cap before being raised. The preparatory work had taken about a year.It was then time to put the bowsprit in position. The bowsprit had to be inserted from the front at an angle of 33°. The traffic management authorities in the harbour assisted by ensuring that all vessels passed by slowly, so as not to cause any swell. The mainmast and aftermast were also raised during summer 2003. A silver coin was placed under the nine tonne mainmast by Sweden´s then Minister for Trade, Leif Pagrotsky. The coin dated from 1738, the year the original ship was completed. Placing a coin under the mast is said to bring a ship good luck. The next steps were the shrouds and stays. When raising the tackle, the hemp rigging is tightened in three stages. As the hemp gradually gives, it is necessary to continue tightening it when sailing. Tightening is performed with lanyards and deadeyes, the old equivalent of the rigging screw. Once the lower rigging was in place and supported, the poles were raised. Topsail poles were raised on the masts, topgallant poles were raised on the topsail poles, and ﬂagpoles were raised on the topgallant poles. The rope for this standing rigging, i.e. shrouds and stays, as well as the running rig-ging, has a combined weight of around 20 tonnes. There are no modern aids to help operate the rigging. It is manoeuvred exclusively by muscle power. Muscle power is also used to operate the capstan on board, which provides extra power when required. In the 18th century, sails made of both ﬂax and hemp were used. It is not certain which material the Swedish East India Company used in the mid-1700s, but hemp and ﬂax were considered to be equivalent in the Swedish Navy. From the outset, the idea was to use sails made of hemp for the new ship, but the trial deliveries did not fulﬁl the stipulated requirements. As a result, sails made of top-quality, semi-bleached linen were used. Two grades of sails with a width of 78 cen-timetres were specially ordered from a textile mill in the UK: Royal Navy No. 1, which weighs 1 kg per m², and Royal Navy No. 6, which weighs 0.6 kg per m². The latter grade has been chosen, for example, for the top-gallant sails, sprit-topsail and smaller staysails as well as the studdingsails, which is only used in light winds. The thread used by the sail-makers is made of hemp yarn tarred and treated with beeswax. The leech ropes are made of tarred hemp and vary in thickness from 12 to 44 millimetres. All the sails have been stitched by hand in the Terra Nova sail loft. This was an enormous sewing assignment, which also required a high level of professional know-how. Sewing the sails took an average of six hours per square metre. This includes all the various aspects of the work: cutting, sewing together, hemming, piercing and leech roping. It took a total of around 12,000 man-hours to complete the main set of sails. The East Indiaman “Götheborg" has a regular set of sails with a total sail area of 1,550 m². If the decision was ever taken to set all the sails, including the leesail, the total sail area would be 1,964 m².All lengths of sail are vertical. The joins, which run from top to bottom, help the sail to retain its shape. However, it is primarily the reinforcement around the sail´s outer edge, the leech, that distributes the force over the sail and provides stability.

The rigging of the Swedish Ship Götheborg. Photo: Stefan Rentsch

The Swedish Ship Götheborg under full sails. Photo: Åke Fredriksson

The ironrings are placed on the masts. Photo: Andreas Haner

Splicing. Photo: Emely Nilsson

All reinforcements and ferrules on the sail are made of tarred hemp as in the 18th century. Reinforcements and fer-rules made of metal were not used until the mid-19th century. In addition to the main set of sails, reserves have been made for the following sails: the fore sail, fore topsail, mainsail, main topsail and mizzen sail. The sailmakers have also produced wind cones, awnings, mast coats, covers and the 60 hammocks. Reserve sails will be taken on the long voyage to China - as well as a sailmaker. In days gone by, extra care was taken when enlisting the sailmaker. In the spring of 2004, all the sails were ready to be bent on. By then the sailmakers had produced a tremendous 27,000 metres of satin stitching! Not to mention hundreds of metres of roping stitches. And around 3,000 holes for various fastenings. The holes were made with a hollow punch and sewn with an inserted ring. Just as in the 18th century, all the rope for the standing and running rigging has been made of the highest quality hemp. Genuine hemp is the best material for ship´s ropes. The hemp used at Terra Nova was imported from Hungary. Producing all the rope in-house enabled complete control over all the various stages. The rope that has been produced satisﬁes all the safety requirements stipulated by the Swedish Maritime Administration. The hemp was delivered to the shipyard as yarn. After ﬁrst having been cleaned of twists and knots, the yarn was dried and tarred. Tarring the yarn before it is twined ensures that enough tar reaches all the ﬁbres in the yarn, thus preventing decay and increasing the rope´s life span. The yarn was then transported to a 300 metre long historical ropewalk in Älvängen, just north of Göteborg. Here the yarn was twined to make strands or ropecores, which were then twined to make rope under the supervision of Danish ropemaking expert Ole Magnus, who possesses unique knowledge of historical ropemaking. Twining the rope by hand makes it more even and ﬁrmly twined, which reduces water penetration in the ﬁnished rope and thus increases its durability. After twining, the rope was transported to the rigging workshop at Terra Nova for boatswain´s work, i.e. pre-stretching, binding, lashing and splicing. The riggers involved in the boatswain´s work also produced block straps, shrouds, stays and jackstays. In addition to the rigging, a large amount of rope was used for various lines, ropes, haw-sers and cables on The Swedish Ship Götheborg. To guide the rope, 700 blocks of various models and sizes are required for the rigging from small single blocks to large multiboard halyard blocks, the largest up to half a metre in length. In addition, 300 reserve blocks were produced. The blocks are exact reconstructions of the blocks found during dives to the wreck of the original ship. Each block was carved by hand from a single piece of elm and treated with raw linseed oil. After drying and ﬁne adjustment, the blocks had one or more blockboards, an axle and a strap added. The blockboards are made of oak, guaiacum wood or bronze de-pending on load and application. Guaiacum is a strong, selflubricating wood from Central and South America, and was already being used for this purpose back in the 18th century.The bronze blockboards have been cast in the traditional manner. In addition to blocks, the rigging workshop also made bull´s eyes and deadeyes. Formerly these were used for setting up, i.e. tightening, the rigging. While still used on some traditional sailingships, more modern vessels now use rigging screws. The ﬁrst sea trial took place on 22 May 2005. With just seven sails and in light winds of 5-6 metres per second, and despite ten large iron ﬁttings from the launch sleds still attached under the ship, the “Götheborg" achieved a speed of over 5 knots. A great moment!