October 2011 – Salty John : The Blog

A bout of bursitis in my knee this week got me thinking about the physical and mental effects of long term cruising.

Bursitis is caused by repetitive movement and pressure on the joint. As a result, carpet layers, footballers and housewives are more likely to suffer bursitis in their knees than is the general population. I’m convinced that trying to maintain balance on a constantly moving deck for six years of my life has left me susceptible to bursitis in my leg joints.

What about ampophobia? This is an obsession with hoarding battery capacity. The sufferer becomes frantic to measure accurately the amps flowing into and out of his battery banks. He becomes convinced that his alternator, solar panels and wind generator are faulty. He tests them exhaustively and joins boating forums to compare his results with other ampophobics who think that they, too, are being cheated by their amp gathering resources. As the condition takes hold the sufferer will accumulate different types of batteries and charging devices, more sophisticated monitoring systems, several types of hydrometer. A battery terminal cleaning brush.

Ampophobia is often caused initially by another condition – meltaphobia, the fear of the boat fridge failing to keep its contents cold. Obsessively monitoring the fridge temperature with a range of increasingly sophisticated thermocouples is a dead give away. Help should be sought immediately before the condition can develop into full blown ampophobia.

Another electricity related hang up is toastitis, the compulsion to design and build a 12v DC toaster. This condition afflicts many long term cruisers once the novelty of burning toast on a wire rack placed over a cooker burner has worn thin. I’ve never seen a successful 12volt toaster, but with all the cruisers out there franticly doing the R&D it’s only a matter of time.

I’m sure you get the picture. You may have your own particular physical or mental condition as a result of long term cruising but, rest assured, once ashore for a short period the symptoms disappear. To be replaced by an overwhelming desire to sell up, quit your job and run away to sea in a small boat.

Wrapped up warmly against the chilly breeze we idled north along the Lancaster Canal on this perfect autumn morning, sun sparkling off the rippled surface.

A convoy of swans escorted us for a while as we pottered past farmers’ fields and beneath stone bridges.

We didn’t meet another boat, nor towpath walker, angler or blackberry picker during our couple of hours on the water.

And then it was back to Salty John Towers for fried egg butties and footie on the box. Bliss.

I wrote an article for the Salty John website about selecting a cruising boat and in it I suggested that an important consideration was whether or not the boat could take the ground safely. Somebody took me to task on this, saying that boats weren’t supposed to take the ground and if I hit the bottom and damaged my boat it would be entirely my own fault. Hmm.

I beg to differ, but I can see how such a view could take hold and how it would be of some relief to boat builders that it be allowed to.

I’m certainly not a yacht designer so I can only speculate that bolt on appendages are favoured because it’s cheap to build that way and it allows more varied keel configurations to be used, designs that would be impossible to accommodate with an encapsulated ballast keel. And it allows the contact area between hull and keel to be minimised and streamlined – this is apparently a good thing when trying to design a faster boat. I suppose that’s why we see keels dropping off, and not just from high tech racing boats; even if the design is technically correct there must surely be less room for error in manufacturing to the required tolerances.

I once bounced a fin keeled Jeanneau Symphonie off the hard packed bottom of Galveston Bay. Not deliberately; I was caught by the tsunami-like bow wave of the tanker I’d just crossed the Houston ship channel in front of.  A day or so later I found that water was trickling in from a crack alongside the keel – when I waggled the saloon table pedestal I could increase the flow! The repair was time consuming and costly.

So, whereas I don’t suggest that bolted on keels are unsuitable for cruising, far from it, I do think a cruising boat should be able to take the ground, deliberately or accidentally, without  major structural damage.

A bad antenna system will make even the most exquisite radio perform badly. To get the best out of your VHF radio you need a top quality antenna system. As radio buffs are always telling us: “A penny in the antenna is worth a pound in the radio”.

VHF antenna systems comprise an antenna (aerial), a feeder cable and a few connectors. If you have a really good quality antenna such as the Metz Manta and use good quality connectors, you’ll want the correct coaxial cable to complete the system.

Coaxial cable for VHF radio is 50 ohm – your TV cable is 75 ohm so you can’t just use some coax left over from that satellite dish installation.

Furthermore, marine cable needs to work in a hostile and constantly moving environment. That’s why it needs to be tinned copper to resist corrosion and the centre core needs to be stranded so it can bend without breaking. A good PVC jacket will keep sunlight degradation at bay.

But what size cable should you choose?

I reckon you need to aim at a transmission loss of no more than 40%  in the run from radio to antenna. This is also the opinion of the offshore yacht racing authorities so I’m in good company.

You’ll want to restrict the line loss (known as attenuation) to about 2.5 decibels (dB).

The picture shows, on the left, RG213 coax and on the right, RG8X.

RG213 (or its slightly lower spec but similarly stiff cousin, RG8U) is a whopping 10.3mm diameter, nearly half an inch in old money. So it’s heavy and doesn’t like to go around tight corners, but it only loses 2.2 dB per 30m length. On the right is its less uptight little brother – RG8X. This flexible fellow is only 6.5mm diameter, much lighter and easier to work with – it loses about 3.5 dB per 30m.

(RG58, which sometimes comes with cheap aerials is 5.5mm diameter and is very lossy – about 5 dB per 30m. OK for short runs, perhaps, but not for masthead installations).

So, if you have a cable run of up to about 25m or so you can go with RG8X, for much longer runs you’ll need to wrestle with RG213/ RG8U.

There you have it.

The October edition of Yachting Monthly carries the latest article in the excellent Crash Test Boat series. YM have all but destroyed a 40’ Jeanneau Sun Fizz in the interests of finding out what really happens when disaster strikes in a variety of ways.

So far they’ve dismasted it, rolled it over, bashed holes in the hull and now we see what happens when you lose a seacock or through-hull transducer.

Seacocks can fail disastrously with no warning if they have been allowed to corrode or have been badly installed. A shocking number of boats are fitted with brass seacocks, apparently, and these can corrode and fail in short order – I saw a report where a boat nearly sank when a 16 month old brass seacock failed through corrosion!

Make sure your seacocks are Bronze, DZR or, my own preference, Marelon.

Anyway, the intrepid Crash Test Boat team deliberately broke off seacocks and smashed transducer fittings to test ways of stopping the influx. They tested the old soft wood bungs we’ve all carried for years and found them to be effective but with some reservation – they rely on the hole being symmetrical for maximum sealing.

Another solution was the Forespar TruPlug, a composite rubber bung that looks like something that might be on offer in a sex toy emporium catering to the more extreme tastes. The Tru Plug was given high marks for efficacy because it conforms to the shape of distorted openings; against it was its price – about £20. You’d probably want to keep one in an obvious location and take it to the site of the failure rather than have one tied to each through hull as you might do with wooden bungs.

The team also tried the old traditional solutions – a carrot and a potato – and both performed admirably with the spud just pipping the carrot on effectiveness.

I love this YM series – it’s both entertaining and of true benefit to boat owners and operators.

We’ve had something of an Indian summer this past week so Minnie, the yacht that thinks it’s a narrow boat, was out and about on the Lancaster Canal.

The term Indian summer was coined in America, by the way, and has nothing to do with the Indian sub-continent. The Indians on the US east coast, aware of the debilitating effect of working and harvesting in the summer heat and humidity, would wait for warm snaps in the autumn to get out into the fields. Hence, an Indian summer is a warm spell in the fall.

On Friday we took an extra couple of hours at lunchtime and tootled down the canal to the Hand & Dagger for a pint and a sandwich. The pub overlooks the canal and there are convenient mooring bollards close by. The ham sandwich on brown bread with a little salad garnish and homemade mustard was delicious, as was my pint of Boddingtons bitter.

All in all a pleasant interlude from the backbreaking work and overpowering stress that constitute daily life at the coal face of Salty John Boat Products and Metz Europe.