The second of the two garboard strakes is the first I have to tackle on my own. The first task is to soften the plank in the steamer so it will take the extreme twist to be asked of it at the front end of the boat, where it must turn inward by almost 90 degrees to meet the vertical stem rebate. Steam is pouring out of the box now, and I slide the plank all the way in, so only a couple of feet remains sticking out – none of the strakes will require steaming at the back end, where the bend is not too severe and well within the tolerance of my 10mm-thick lengths of larch. A glance at the clock: twenty minutes, starting now.
This is the procedure, which will be followed for every subsequent plank: when a plank emerges from the steamer it must be quickly and progressively bent and clamped into position along its length while the fibres are still sufficiently flexible to allow it to conform to the shape demanded by the three-dimensional tyranny of the moulds, stem and transom. The front end of the plank must be clamped in position first, roughly where it will end up in the stem rebate – it has been cut so it more or less matches the curve of the stem rebate, and it will be fine-tuned later. Its long tail can then be used as a lever to work the rest of it down over the moulds, applying clamps and nippers from front to back as you go. With the garboard, the plank is held tight to the hog; every other plank will be clamped and nippered to the preceding plank.
The important thing is to work quickly, before the effect of the steaming wears off. It’s also important, as I discover, to remember to slip on the rigger gloves before pulling the extremely hot plank out of the steamer. I surely won’t forget next time . . .
My first plank goes on, eventually, in a blur of steam burns, curses, general panic and clumsy fumbling. It’s only a rough fit at this stage, to introduce the plank to the new shape that’s required of it. Once it cools down and ‘sets’, the clamps can come off again and the fine detail work can begin.
But clamping the front of the plank in place isn’t as easy as it sounds. There’s a tremendous amount of force in a freshly bent and twisted plank and, although one side of a clamp can be persuaded to sit fairly happily on the square stem, its opposite number struggles in vain to find purchase on the angled surface of a plank fairly fizzing with kinetic energy.
Your basic clamp, in other words, can’t get a grip. Instead, Fabian has lent me a homemade device that looks a little like a medieval instrument of torture. The job of holding the front ends of the planks in place on the stem couldn’t be done without it, but setting the damn thing up is not easy – not least because it has to be manhandled into place with one hand while the other is trying to control and manoeuvre into position for clamping a hot, 10ft-long plank wobbling around with a freshly steamed mind of its own.
The device consists of a heavy metal frame, which is held on the stem with a G-clamp. On the frame is mounted a threaded wooden rod, as thick as a finger, at the business end of which is a padded block that is screwed down to hold the end of the plank in the correct position. This rod is in turn mounted in a hinged bracket, which allows its angle of attack to be adjusted so the padded block can land square on any plank, no matter how crazy its angle relative to the stem. But it’s an unpredictable business. More often than not, the tremendous force that builds up in the plank as it’s coaxed down and bent over the first mould frees it violently from the grip of the block. Worse, if the G-clamp holding the device against the narrow side face of the stem hasn’t been positioned just right, the whole heavy contraption is catapulted off.
This happens on my first attempt, just after I have managed to apply two nippers aft of mould one. There are two immediate effects. The first, as the front end of the plank twangs free and the hefty clamp assembly lands with a sickening thud on my right foot, is to remind me that I bought a pair of steel-capped shoes in which to build this boat and I really ought to be wearing them. The second is that the plank is now flapping free of crucial restraint at its front end and losing flexibility by the moment.
Without thinking, and while still grasping the wayward plank in one hand, I reach down quickly with the other to recover the clamp from the floor and promptly stab myself in the face with the back end of one of the nippers. Luckily, it just misses my eye. This is a lesson in situational awareness in an alien and potentially hostile environment. I learn quickly not to move suddenly, or without looking where I’m going first.
I’m aware of the blood but the adrenaline is flowing so I barely register the pain as I scramble to re-seat the clamp. The two nippers that I had managed to get on now have to come off again so I can relocate the front end of the plank into the rebate, and there’s a right way and a wrong way of releasing them. The right way is to pull out the wedge first, which takes all the considerable bite out of the nipper. The wrong way, which I proceed to demonstrate, is to simply grab the nipper and heave it left and right until it suddenly shoots off the plank, with the tensioning wedge still in place, and snaps shut on your finger instead. The nipper lives up to its name.
Eventually, I get the clamp back on the stem and the padded block screwed down onto the plank, taking great care this time to ensure that it’s dead square to the surface. It holds. With my right hand I push the plank down again onto the first mould, every moment fearing a repeat of the first performance. The clamp is still restraining the front end of the plank, and I shove a nipper in place just behind the mould. With both hands now free I work quickly, driving on nippers every couple of feet or so until I’ve worked my way to the back end of the boat. Here, the deliberately overlong plank extends over the edge of the transom, to which I secure it with a G-clamp hooked under a block screwed onto the inside face. In between the nippers I fit more clamps, making sure there is good contact between the hog and the plank all along its length. Bristling with clamps and nippers, the boat looks a bit like a porcupine.
I stand back and take a breath. Somehow, I’ve got away with it. The plank has allowed itself to be contorted into the desired shape without breaking. The fibres will quickly lose their temporary flexibility and the plank adopt the new shape permanently. Hoorah.
But bending the plank into the correct shape is just the start.
The curve of the front edge of the plank bears little resemblance to the curve on the stem rebate into which it must fit snugly and the plank will have to come off again so it can be cut to the correct shape. It’s also lying proud of the rebate, which means I’m going to have to chisel out more of the stem. I think back to how I sweated over this rebate when I was making the stem. Now I see that it can only be finished properly once the planking starts to go on: each plank will let me know exactly how far back it needs the bearding line to be. Mental note for next time (next time!): technically speaking, I needn’t have sweated the bearding line at all.
But before it can be taken off again, the plank must be left to cool down for a little while and, while it does, I do the same, taking a stroll outside. At some point, unnoticed by me, the sun has come out and there is no sign of the April shower that soaked me on my way to the shed this morning. Swifts, or maybe they’re swallows, are flashing through the air, diving in and out of the barn opposite the shed. Oh yes, I remember dully. Spring is here. The double doors of the barn are wide open and inside John is working on his E-type. As I limp past, heading for the toilet to check the damage to my face in the mirror, he looks up, says hello and gives me a quizzical look.
‘Who won?’ he asks.
I smile, but it’s only when I reach the mirror that I fully understand the question. The back end of the nipper has gouged out an impressive flap of skin on my forehead, releasing an awful lot of blood that is now congealing on my cheek and temple. In other news, an impressive purple blister has formed on my right forefinger where the other nipper struck and the big toenail on my right foot is throbbing where the heavy stem clamp touched down. Later, the nail will fall off. If I carry on at this rate I shall be hors de combat long before the battle is over.
It will take me six days to get the garboard plan
k right – not finished, mind, just ready to be fixed in place. Six days. In the process, it will go on and come off the boat maybe thirty times or more. I lose count. Or, rather, I stop counting because it’s just plain demoralising.
After several goes, each one of which eats up another millimetre or so of planking, I finally manage to fine-tune the front edge of the plank so it nestles perfectly in the stem rebate. Now I understand why each plank is cut a foot or more overlong, to allow for these incremental forward adjustments. At the same time the depth and angle of the rebate has to be carefully adjusted with a chisel, one shaving at a time.
The next task is to ensure that the bottom edge of the plank sits neatly in the rebate cut into the keel. With the plank clamped in place, it seems easy to see exactly what needs to be done. There’s a gap between the bottom edge of the plank and the keel here, and a bulge in the plank there, and another there. Flatten out those little bulges and all will be well – the gaps will close. I mark them with a pencil, remove all the clamps, mount the plank in the jaws of a Workmate and, with a block plane, carefully smooth out the discrepancies. Easy. Except, when the plank goes back on the boat a whole new set of gaps and bulges has appeared.
This depressing, iterative exercise goes on and on. By day three I am despairing that it will never end, and that I will whittle away the plank until it is no wider than a toothpick. The process infests my dreams. This is why, of course, that in addition to being cut too long, the planking is also left too wide, to allow for such adjustments. But as the plank goes back and forth it is shrinking perilously close to the point where it won’t be wide enough, and will have to be discarded.
Eventually, I get the fit of the plank and the keel more or less right and, with less than a millimetre of wood left to play with along some parts of the top edge of the plank, I decide to quit while I’m only a little behind. For the first time I find myself uttering the fateful words, ‘It’ll do.’
With the bottom edge of the garboard hard up against the keel and the clamps still firmly in place, the line defining the top edge of the plank can now be marked up for cutting on the bandsaw. Off comes the plank one last time, the bendy curtain rail connects the marks transferred from moulds, stem and transom, and with a great sense of freedom I fire up the bandsaw and trim the plank to within a sliver of the pencil line. Its blade will never produce a perfect finish, which is achieved with a sharp and finely adjusted block plane once the plank is clamped in the jaws of a Workmate. This involves a lot of squinting down the edge of the plank, to ensure the emerging curve is ‘fair’. A line is fair, says McKee, ‘when it passes through its guide marks without any abrupt changes in direction’.
Again, ‘it’ll do’. The true test will come when all the planks are on the boat, which is when any visual discrepancies will shout, ‘Look at me!’
With the plank back in position, clamped and nippered, I drill holes for the screws that will hold it down at the stem and on the edge of the transom, and for the copper nails that will be driven through the plank and the hog for riveting. A seam of mastic – foul-smelling, evil brown stuff, which gets everywhere, and stays there – is spread along the surface of the stem, keel and transom where the plank will land, in a bid to create some sort of seal to compensate for any poor fits.
And so the stage is set for my first excursion into the ancient art of riveting.
16
NAILING IT
‘Nægl. Sense: nail (clenchnail, rivet) . . . In early medieval northern Europe (especially Scandinavia), the most common way of joining a ship’s planks to each other was with metal nails (compare also nægled) . . . In ships of the Nordic tradition, the nails were driven from the outside of the planking through a flat piece of metal (rove) on the inside and flattened against the rove, thus forming a kind of rivet.’
– Katrin Thier, Old English Sea Terms
14 APRIL 2017
There is, clearly, something counterintuitive about drilling holes in the hull of a wooden boat, but doing so is nevertheless the first step towards ensuring that the overlapping planks that form a clinker hull will be watertight. Provided, of course, that you get the riveting right. The square-shanked copper nails and round washers that will hold the planks together may be the smallest components on the boat, but collectively they are the most important.
In 2008, a new theory emerged to explain why the White Star liner Titanic sank so quickly 370 miles southeast of Newfoundland, with the loss of more than 1,500 lives, after striking an iceberg on the night of 14 April 1912. After trawling through the archives of the Belfast shipbuilder that built the ‘unsinkable’ ship and analysing forty-eight iron rivets found at the wreck site, researchers concluded that Harland and Wolff, scrambling to source the nine million or so rivets it needed for the doomed ship and its two sisters, the Olympic and the Britannic, may have compromised fatally on quality.
Tim Foecke, a metallurgist with the National Institute of Standards and Technology in Maryland, USA, found that the wrought-iron rivets contained an average of three times more slag, a brittle residue of smelting, than was desirable. ‘In addition,’ he wrote in Materials Today in 2008, ‘the slag was in large pieces [and] both of these facts point to fabrication by inexperienced tradesmen, as wrought iron was made by hand at the time.’ The source of this poor quality material became clearer, he and his fellow researchers found, when Harland and Wolff’s contemporary company minutes were examined. These revealed that ‘pressure to finish Titanic caused the company to order wrought iron that was one level below that generally specified for rivets and they had to use suppliers previously uncertified for this application’.
The result, they concluded, was that when the ship struck the iceberg a significant number of the faulty rivets sheered, causing the 1in-thick steel hull plates to open near the bow and allow the North Atlantic to rush in. The ship was designed to be unsinkable, provided that no more than four of her sixteen watertight compartments flooded. A breach big enough to compromise even four compartments was thought beyond the realm of possibility but, thanks to the below-par riveting, all six at the front of the ship were inundated.
The Nottage dinghy is, of course, made of wood, not steel and, at just 10ft long, is slightly shorter than the 882ft Titanic. But, like the ill-fated liner, its ability to keep out water will depend entirely on the quality of the riveting. And, as I contemplate the task ahead, it isn’t lost on me that my first attempt at riveting is taking place on 14 April, the 105th anniversary of the loss of the Titanic.
The hull of the Nottage consists of twenty overlapping strakes, each of which will be fixed to its neighbour by twenty riveted copper nails, set at intervals of 140mm. To this total of 400 rivets will be added 400 more, longer so they can be driven through the strake overlaps and the vertical ribs that will be steamed into place once the hull is complete. When all is done, each strake will be held to the next by a row of forty rivets, each just 70mm from the next. In addition to the question of how well the lower 20mm of the edge of each strake conforms to the upper 20mm of its overlapped neighbour, it is on the correct placement of these 800 riveted copper nails that the integrity of the hull of the Nottage dinghy will ultimately depend.
The use of metal rivets to fix the planking of clinker-built boats dates back at least 1,700 years to the Nydam boat, with its hull of five strakes held together with iron nails.
If any part of a wooden boat is going to survive centuries underground, it’s the rivets, which often give archaeologists the vital clues they need to piece together the otherwise chaotic evidence yielded by excavations of sites containing long-buried ships. Two such sites are within 15 miles of where I am building the Nottage. In the summer of 1862, as the Nydam ship was being excavated in Denmark, two Victorian gentlemen-archaeologists stumbled on the remains of a ship in a field at Snape, a village on the Alde river 5 miles inland from the coastal town of Aldeburgh. What they’d found was the first Anglo-Saxon burial boat to be discovered in England. As an account publis
hed in The Field, ‘the Country Gentleman’s Newspaper’, on 17 January 1863, revealed, when they dug into one of several mounds on what turned out to be an Anglo-Saxon burial ground they first found fragments of wood, ‘perfectly decayed though retaining its form and fibre’, a ‘magnificent antique gold ring’ and ‘all around at equal distances . . . small masses of iron coated with sand and entirely oxidised’.
These pieces of iron were rivets and, together with the position of a few scraps of surviving wood, their number and distribution in the ground led to the conclusion that here had been buried a 48ft clinker-built ship, with about eight strakes a side, dated by the items found with it to about AD 600. Uncannily, for me at least, the spacing between the rivets – 150mm – was exactly the same as on the Nottage dinghy.
It would be another seventy-six years before Edith Pretty, the landowner at nearby Sutton Hoo, only 8 miles south of Snape on the north bank of the River Deben, got to wondering about the mysterious tumuli on her land and invited a local amateur archaeologist to take a look. Basil Brown, self-taught but recommended to Mrs Pretty by the curator of Ipswich Museum, duly set to work, assisted by his employer’s gardener, John Jacobs. On 11 May 1939, Jacobs emerged from a trench they had dug into the largest of the mounds clutching ‘a bit of iron’ – a rivet. Many more followed and, as they were carefully unearthed one after the other, so the ghostly impression of an 89ft oak clinker ship, built with nine strakes each side, appeared. None of the wood, long consumed in the acidic soil, remained, but the rivets, along with the distinct imprint of the planking that had been left in the ground, survived to tell the tale of the ship’s shape and construction.
How to Build a Boat Page 19