Having cleared with the South African banks that foreign currency brought into the country would be permitted to leave in the form of a boat, I signed several forms with Barclays agreeing currency transfers at four specified dates in the future. What impressed me so much was that, when each of these dates came up, I saw that the rates estimated by Barclays were never more than one per cent in error, and the error was always in their favour. How did they know so far in advance how the exchange rates would vary?
On this occasion the international banking system did us no harm. There were many times later, when we were having to work with four or five different currencies simultaneously, that we longed for an easier means of handling money. Ideally there would be one world currency, one basic system of taxation, and one broad set of customs rules. In such a world there would be no currency speculation, legal or illegal. No black markets. A huge reduction in regulations and bureaucracy. Substantially less smuggling – and the crime that goes with it. And we – and other travelling folk like ourselves – would be spared so much of the unjustified suspicion of zealous officials that at times made life afloat rather difficult.
But how could such a utopia ever come into being? Too many international bankers, lawyers, financiers, politicians, officials, agents and criminals would lose their livelihoods. That would never be allowed to happen!
10. Some Technical Matters
This story would be incomplete without mention of some of the more important technical details involved in Tin Hau’s construction. The non-technically minded, keen to draw nearer to the launch and our subsequent adventures on the high seas, can pass over the next few sections, in which I propose to describe briefly the following:
The sails, yards, battens and running rigging
The masts and standing rigging
The steering
The windlass, chain and anchors
Plumbing
Power generation
Paints
The reader should therefore skip to section 11 unless he or she is particularly interested in some of the details of how to construct a large steel junk.
On finishing the book, if fired with the thought ‘I would like to sell up, build a boat and take to the life afloat’, the reader should return to these pages – which hopefully will have become more significant.
10.1 the sails
Changing headsails on a wet heaving foredeck may be the racing man’s idea of fun, and a pleasure he would not want to be without, but not everyone who goes to sea feels the same way. Cruising folk generally like to keep as dry as possible on deck. They like work to be easy rather than difficult. And they like it to be cosy and warm down below. Sharing a berth with a wet sail bag is not considered desirable. Bagging and unbagging of sails is something to be avoided.
One solution to the problem of how best to stow and reef sails, commonly adopted on cruising yachts nowadays, is the ‘furling’ headsail – a foresail that can be wrapped round and round itself to various positions of reef, and eventually to the fully stowed position. The same system is sometimes used on the mainsail. There are, however, two main drawbacks: firstly, the very considerable costs involved; secondly, the fact that the complex furling equipment can go wrong. Anyone who believes Murphy’s laws, as I do, knows that anything that can go wrong will go wrong, and this will happen at the worst possible moment. A sail that will not come down spells total disaster. In the course of our travels, we came across numerous yachtsmen with problems over their aging furling gear – sometimes waiting months in port for a spare part.
I had originally thought we would choose furling headsails; then we started to learn about Tom Colvin and the junk rig. I considered carefully all the advantages and disadvantages of this rig, and concluded that what had been right for centuries of Chinese families living aboard their junks would also be right for us. We would have one sail on each mast, ready at all times for use; a simple means of reefing with no complex gadgetry; no worries about sails splitting from top to bottom (as has happened to me on other yachts); no expensive winches; and no stowage of sails below decks.
Later we had experience in the junk rig, but at the outset of our venture in 1983 we could only have trust and blind faith in the oracle, Tom Colvin. As he seemed to have an answer to every problem I raised, I decided not to become too involved in a study of all the different junk sail variations, which are as numerous as western sail variations. Tom’s latest arrangement for Kung Fu Tse would be good enough for us. I sent a copy of his drawing to Cheong Lee in Hong Kong, together with instructions on the material to be used.
Figure 5 shows the details of Tin Hau’s three sails.
It will always be a matter of regret to me that I was unable to experiment with the basic sail shapes, batten arrangements, and mast positions – even though we may have had a near optimum arrangement. Obviously, changes in these areas would have been major and expensive, affecting not just the sail and deck plans but the interior as well. Perhaps nothing would have been gained. Yet, based on our experiences on board Tin Hau, I would like to have tried, for example, a mizzen twenty per cent smaller and slightly aft, a main fifteen per cent larger and also slightly aft, and a variety of different foresail arrangements, including – perhaps – a small self-tacking jib on a short bowsprit. To make such alterations on Tin Hau would almost certainly not be practical or worthwhile, but I would find it fascinating to test a fleet of model junks on a pond, and to see the information gained used to build another full-sized junk rigged vessel (we would not want to build another one ourselves!) Large sums of money are spent on improving what I call the ‘western rig’, and volumes are written about it by experts. Why cannot some funds be made available for refining the junk rig?
10.2 the yards
We followed Tom Colvin’s advice in making the yards much heftier than the battens, since they carry the entire weight of the sail and are always in use – even in storm conditions when most of the sail is reefed. Also the yards need to be heavy, so that the sail will drop quickly and easily when being lowered. We made them of laminated Philippine mahogany, this being all that was available to us at the time. Having experienced yard breakages on two occasions, I wish we had been able to find some spruce of sufficient length and thickness, so that we could have done without the laminations. The dimensions we used were fine, each yard being approximately two and a half inches thick and five and a half inches in depth at the halyard position and for about one third of the total length of the spar, tapering off to approximately two inches by three inches at each end.
10.3 the battens
The battens– six on each sail – proved to be an area of great interest. Colvin had indicated they could be made of aluminium, but we thought this might be noisy, as well as expensive. They could also be made of wood, but they might not be strong enough. Or they could be made of plastic piping, but this might deteriorate in the sun. Finally, they could be made of bamboo, but where could we find some in Port Elizabeth, seven hundred miles from the tropics?
Lynda took this as a challenge and set off on a bamboo hunt. She decided to start with the local parks department. They told us they had no bamboos of a large diameter, but that we should try the museum.
Taking their advice Lynda went to the museum, where she was more successful. She learnt that a citrus farm about twenty kilometres out of town, Amanzi Estates, used bamboo for windbreaks. She phoned the owner of the estate, Mr Niven, and met with a most favourable response.
‘Take as much as you want,’ he said, ‘as long as you look after the cutting and the transportation.’
So we enjoyed a welcome break away from the hangars and drove to Amanzi Estates. There, to our amazement, we found that the bamboos were huge. They had been planted at least fifty years before and were obviously of sufficient size for our purposes.
What size did we want? What exactly are the wind pressures on a junk sail? How ‘bendy’ should a junk batten be? What sail camber should it allow? How strong should it
be? How heavy? Do bamboos need any special treatment before they can be used? How can they be straightened if they are cut crooked? When will they turn from green to brown? How long will they last? Are there different species of bamboo, some good for our use and some bad? What do the Chinese do?
These questions went round my head for weeks as I searched for the answers.
The lengths we required were shown on Tom Colvin’s drawings: eighteen feet for the main, sixteen feet for the mizzen and fifteen and a half feet for the foresail. I am using feet and inches because Tom, being American, gave all his dimensions in this way. We actually had great problems in South Africa finding an imperial tape measure. Luckily, having been brought up to understand both systems, I was able to switch easily from one to the other. I like to use millimetres when taking and writing down a measurement, but I think in feet and inches when visualising a feature such as the length of a berth, or my own height.
The required diameters and wall thicknesses of the bamboos were much harder to assess. I spent some time researching bamboo in general and also carrying out various theoretical calculations.
Luckily for us, it was at about this time that Port Elizabeth was visited by two junks on their way westwards. One was Rajah Laut, a beautiful Malaysian junk, skippered by a quietly-spoken and obviously highly competent German called Wolfgang. The other, Elf Chine, had come all the way from Canton under a mixed nationality crew (mostly French) in their twenties. She was twenty-five metres long and built only five years earlier in the traditional manner of a South China Seas trading junk. Whilst admiring the beautiful woodwork and many features, such as the long tiller operated by block and tackle and the huge capstan for raising the mainsail (operated by two or more people), we were horrified to hear the tales of breaking masts (one more was to break in the Atlantic before they got back to France) and the sheer manpower (or womanpower) needed to operate her. I was happy with our philosophy of being prepared to combine the best of the east with the best of the west. Our masts would be made of aluminium if I thought that was best. On a more positive note, South African bamboos– or at least those found near Durban– were highly praised. ‘The best we have found anywhere,’ said the crew. I wondered slightly why they had had such experience in looking for bamboos in so many countries. Did they break often? However, on balance I was encouraged. The Amanzi Estate bamboos were becoming more and more desirable.
We also learnt from the crew of Elf Chine that the maintenance of bamboos was nil, that we must cut them at the right time in the lunar cycle (this we ignored!) and that we must cure them by floating them for some weeks in the sea to leach out the sugars in the sap.
Armed with a bit more knowledge, we set off again for the Amanzi Estates, this time with two cars in the company of Jan and Jeff, visiting from Swaziland. We passed a most enjoyable few hours sawing, hacking and tugging at selected bamboo poles. I had decided at this stage to go for diameters of between two inches and three and a half inches. Generally, the best bamboos were in the middle of the thicket, where they were hardest to reach. However, by the end of the day, with the aid of ropes, chains and the vehicles, we had thirty-one fine poles laid out on the ground. This would be a large enough number from which to choose the eighteen we actually needed.
Back in Port Elizabeth, I examined these poles more carefully, cut them roughly to length, weighed them and placed them in the swimming pool belonging to Lynda’s sister and brother-in-law (Sally and Wally Wessels). A swimming pool was considered more practical than the sea; and, being winter, no one was wanting to swim. The main inconvenience to Sally and Wally was that the pool’s automatic ‘Kreepy Krawly’ cleaner had to be removed.
Some months later, the poles came out again, looking much the same – green and crooked. We took them on the back of the bakkie to the hangar, making several trips. Then we lashed them tightly to the hangar’s vertical girders in an effort to straighten them.
A further two to three months passed whilst the bamboos turned from green to golden brown. The moment of truth came when we unlashed them from their supports. Would they spring back to their original shapes?
The answer, thankfully, was no. They emerged straight. On weighing them, I discovered that their weights, which had worried me earlier, had more than halved to a respectable four to nine kilograms per pole, which worked out to be between 0.8 and 1.6 kilograms per metre length.
At this stage I needed to determine which poles should be used in each batten position. It was clear that the uppermost two battens on each sail needed to be the largest. The lower battens could be smaller, as they would probably not be loaded at all in strong winds, lying within the stowed bundle of the reefed sail; and, when unreefed in lighter winds, the wind forces would obviously be less.
I decided upon a simple load test for sizing the largest battens: Lynda’s brother, Andy, weighing eighty kilograms, would have to stand on the middle of a bamboo resting on supports sixteen feet apart. The bamboo should not deflect more than twenty-four inches or less than nine inches and, on bouncing, it should not break.
This crude but effective rule of thumb resulted in us choosing three to three and a half inch diameter bamboos for the upper pair of battens on each sail and two to three inch diameter bamboos for the lower ones. For the lowermost batten (or ‘boom’), I made the size slightly larger than that strictly needed for wind loading. We felt that some weight was needed at the bottom of the sail.
Luckily, we had more than enough poles available for the eighteen ‘working’ battens. We decided to carry three poles on deck as spares; and we rejected the six worst poles as being surplus to our needs.
Having worked out the loading in this way, I was able to use the knowledge later when it came to designing the masts. Also, I could check that the entire running and standing rigging was designed to the same loading – in other words, the sails were as strong as the battens; the battens matched the masts; the masts matched the deck and keel steps and also the stays; the stays matched the dead-eyes; and the dead-eyes matched the bulwark eyes and shackles. All very well in theory, but gale number three on our maiden voyage produced two zones of weakness, as will be seen.
One important aspect of the traditional Chinese batten escaped me at the time, which we were to regret afterwards. We would have done better to have used two smaller bamboos per batten position, rather than one large one, and these should have been staggered with respect to each other. For example, the uppermost mainsail batten should have consisted of two 2½" diameter bamboo poles each sixteen feet long and overlapped to make up the required length of eighteen feet. This would have been better than one three and a half inch diameter pole just greater than eighteen feet in length. The problem was that due to the nodules in bamboo it was impossible to cut a pole exactly to the required length. As a result of this initial misjudgement (eventually put right in Cyprus), we had innumerable headaches with our sheetlets catching the short protruding lengths of batten on the leach of each sail. This meant scaling up the sail to free the snarl-ups, often in the middle of the night and in bad weather.
Apart from this one mistake, we were very happy with our bamboo battens. In spite of all the misuse we gave them, only one ever broke.
10.4 the running rigging
Moving on from the battens to the running rigging, I started with the most familiar ground to me from past sailing experience – the main halyards, the ropes needed to haul up the sails. Again, working on the old principle of keeping it simple (and thus long lasting), I did not want halyard winches. I preferred to use block and tackle.
I envisaged the weights involved in hoisting the largest sail, the main (refer to the sail plan). First we would just have to lift the twenty-five kilogram yard clear of the stowed bundle. Then the yard, the top panel of the sail and one batten (say forty kilograms in total). Then two panels of sail. Then three. Then four, five and finally the full six panels of sail (say one hundred kilograms at this stage – getting heavy!) I decided to allow a further on
e hundred kilograms for the fact that the sail might be partially filled with wind. Thus I calculated that in extreme conditions, a weight of two hundred kilograms would have to be lifted, ideally by one person weighing only sixty-five kilograms. This would require a mechanical advantage of three-to-one, assuming that all the person’s weight is on the halyard; but, allowing for block friction, I felt I needed a purchase of four-to-one. This meant a double block on the yard (we used Barton cruising blocks, costing about seven pounds each in 1985) and a double block with becket at the masthead.
We quickly discovered, however, the problem with the block and tackle system: when the sail was fully up, we were left with a mile of rope at deck level – or to be exact, in the case of our main, thirty-five metres. This had to be stowed quickly and conveniently. Over the period of our trials on Tin Hau we evolved a system that still remains. For each sail we made a pin rail which we lashed to the standing rigging at about chest level just above the halyard cleating-off points on the bulwarks. The procedure with loose halyard rope was then to coil it directly on to a selected pin (holding the increasingly heavy coil was thus avoided). When finished, the entire coil would be turned upside down on the pin, ready for lowering. In the case of a one panel reef, the top three turns would quickly be uncoiled and laid out on the deck, prior to uncleating the halyard. For a two panel reef, six turns would be laid out. This way we avoided nasty rope tangles. Time was often very short when reefing or lowering sails.
Cutting the Dragon's Tail Page 3