Fending for ourselves

For years, science has wondered, what is the harshest environment possible? Is it the merciless Kalahari, whose awe-inspiring vistas hide geology that laughs in the face of mere humanity? Is it the surface of Venus, bombarded with poison and crushed under such pressure that even our most hardy submarine would crumple like a soda can in seconds? Or is it the aft port flank of a Dutch barge in the Thames, where bloody great collar barges can chew up steel-belted radial tyres, pry open steel chain links, sever braided steel cables and crush half-inch shackles like the dreams of a barge owner who just wants his home to stop ringing like a bell when the 7am commuter boat rolls past?

Mere mortal tyres are no match for the might of the river

My earlier optimism about chains and cables has been only partly justified. The cables do hold up better than the wimpy ropes we had on hand before, but the weak link is the shackle where the ends are joined. Even the biggest end up bent within a couple of days. If we’re lucky that means they can’t ever be opened again; if we’re unlucky, they pop open and we lose yet another tyre to the river. Along the side of the boat the tyres are generally surviving at least a couple of months, but in the highest-stress locations – the chain a third of the way back from the bow, and the port side at the very back – if they don’t get torn off by then, they end up eviscerated.

Imer, the moorings manager with the strength of ten men, has very kindly hauled up a couple of monster tractor tyres for us to put in place. We came home one evening to find a very welcome addition to the big chain.

A tractor tyre shields us from the honking great chain

Sadly since then he’s busted his arms and can’t help us mere mortals heft the aft tyre on for a few more days. In the meantime I’ve tried to find the most damage-proof method of mounting a standard car tyre: Two cables for redundancy, none of the cables running unguarded through places where both boats can touch, and mounted “sideways” so that there’s less distance for it to be pulled up and down by the motion of the boats. Early signs are good, although naturally the shackles were both squashed within 24 hours. C’est la vie…

- posted by James O'Brien on 14 April 2008, 20:07 in