Heaven and hull

Bitumen, varnish and gigantic mallets: The joy of drydock by Peter Watts.

Living on a boat is rewarding in so many ways, but never more than when you are whacking its hull with a gigantic mallet. A boat can feel like such a fragile place, when you are rocked violently by the wake of every passing craft or woken in the night by random sounds that pierce the seemingly slender steel. At times, it feels as if your home is made from paper. But then, every four years, you go to drydock, and while your boat precariously perches on brick piers in a drained basin you set about it violently with a mallet. That’s when you discover how damned solid it actually is. It’s very reassuring.

Looking back, I’m not entirely sure why we attacked our boats with hammers – it may have had something to do with measuring the thickness of the hull – but the whole week is a bit of a blur. My neighbour and I had taken our narrowboats in tandem from Lisson Grove to Hayes. We’d booked the drydock for five days, time that would be spent engaging in fierce physical labour amid a head-spinning cloud of varnish, paint and bitumen, then yakking round a barbeque with the garrulous, convivial Irishman who ran the dock.

Blacken the hull

Drydock is something every boat has to go through every four years, and it’s also a rite of passage for boaters. It’s essentially a check-up of the hull, that part of the boat that’s submerged, unseen, beneath the water. Who knows what condition it is in, what knocks and scrapes it has endured from messy five-point turns? Now, this thing within which your entire life rests is to be inspected. And it feels like your suitability as a boater is also under review. Have you got what it takes? Do you know how to use a mallet? Can you gossip?

To start, boats are taken out of the water. They can be dragged on wheels or lifted by crane, but in our case they were steered into a covered dock and secured on plinths. The dock was then drained like a lock, leaving the boats, which we still slept on every night, sitting awkwardly and unnaturally above our heads.

The main objective is to ‘blacken’ the hull, coating it with thick bitumen that protects the hull from scrapes. First, though, you need to clean it with jet spray and go over rust with an angle-grinder. Next, you apply the anodes. These are bits of metal that have a higher electrochemical value than steel, so will start to corrode before the hull. All boats are susceptible to galvanic corrosion, caused by the different metals in the water which create an electric charge, with your boat acting as a sort of battery. Sacrificial anodes attached to the hull will take the brunt of the resulting corrosion. About this, I knew nothing until I went into drydock.

Sweating bitumen and wine

You then take soundings of the hull to discern whether additional steel plates are required – that’s when you discovered you could hit the hull as hard as you could and leave not a dent. Assuming all is fine, blacking can begin. The idea is to slap on as many coats as possible, and then find other jobs to do while it dries – or spend that time trying painfully to peel away bits of cooled bitumen that have stuck to your hair or skin.

It’s exhausting, dirty work, especially if you are not used to manual labour and are unduly sensitive to the incredulous guffawing of the drydock owner, in our case a gnarled veteran who sweated bitumen and wine and got a kick from watching callow soft-handed saps struggling before he stepped in to sort it out. This was his world, but he took pride in sharing skills, passing on tips to another generation, even office types like us.

As he did so, he’d gossip about fellow boaters, many of whom, like us, had spent a few days in his kingdom several years previously. As he did so, he’d liberally share his wine so that when his wife returned from work she would take stock of his mood and then loftily pronounce whether he had enjoyed a one or two bottle lunch. Dinner would pass in much the same way, and then we’d settle down to sleep on our stranded boats, stinking of grape and tar, adrift from the usual calming currents that rocked us to sleep but confident, at least, that we weren’t going to sink any time soon.

Last date edited: 22 January 2015

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