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Ever heard of a wangle 'andle, no I suppose not. It was a very localised colloquial term for a particularly shaped bent piece of steel that was both essential but hated by anyone who drove a motor car.
My father was a man you had to take seriously. He never swore (or at least he said he didn't) but he did have an extensive vocabulary of appropriate words and phrases such “flipping heck” or “blooming thing” which displayed times of a distinct lack of peace and harmony in his life. Such times particularly centred around this infernal piece of steel rod that he would insert into the front end of his motor car and attempt to engage in the front of the engine. He would then brace himself and swing this thing having first pointed out to anyone listening that if you got it wrong you could easily break your thumb.
Round 1
Car wins.
Round 2
Car wins
Round 3
Car wins
“Mutter, mutter, blooming mutter.”
Come round to drivers seat, adjust choke “mutter, flipping mutter”
Round 4
Dad wi.... no false alarm car wins.
Round blooming 5
Car wins
Round flipping blooming 6
Dad mutteringly wins.
Jump in driver's seat, foot on accelerator, sorry car wins.
Round 7.......
This is all very well but imagine a modern day woman in her high heels and makeup off to work with her wangle 'andle in her delicately manicured hand bracing herself in front of her pink Honda Jazz, somehow I think not.
But then someone had an accident. We can't imagine what the circumstances might have been or what damage may have been caused to sensitive parts of the body but someone discovered that if you stick two pieces of dissimilar metals into a bowl of acid things start to happen like blue flashes, sparks and in fact all manner of dramatic electrical things.
It's all to do with those tricky little electrons (they're little devils you know). You see they like some kinds of metal more than others. So given half a chance if metal is dipped in some nasty acid they get all excited and head off for a holiday in more comfortable surroundings. More electrons in one place than another is a potential difference, a voltage no less and we have - a battery. All that was needed was someone to invent an electric motor and the wangle 'andle was to everyone's relief made redundant .. but just a minute the battery went flat!
Oh dear back to the drawing board.
Ah! but If I connect my wangle 'andle to the front of the electric motor and turn it backwards I can force those little electrons back to where they came from. Eureka! I have invented a generator and the battery is recharged.
So what has all this got to do with anything? Well quite a lot actually. If it wasn't for batteries we'd all have wangle 'andles on our ipods wouldn't we? We'd all have bad backs from starting our cars and the English language would probably be far more colourful than it is today.
Unfortunately this wonderful phenomenon has a down side. Two dissimilar metals and a bit of water or even moist air and those electrons start to go travelling and as they leave one piece of metal it starts to fall apart leaving oxides or salts which in the case of ferrous metals is iron oxide or rust. It is an electrochemical reaction. This is particularly bad in salty environments such as we find near the sea.
So how do we stop rust?
Well the simplest and most common way is to insulate the steel from the environment by coating it with paint. This is usually fairly effective but any sort of flaw in the paint coating will allow rust to start. Once the coating is breached the electrical activity can be concentrated at that point and so rusting may progress even faster than if the steel wasn't painted at all. The addition of lead and zinc to paint may reduce rusting but has limited effectiveness because the paint tends to insulate the zinc and lead particles. Lead paint also has a tendency to keep the kids quiet.
A better option is galvanising. No I am not talking about the process of trying to get that lazy son out of bed. Galvanising is the application of a thin layer of zinc which, like lead, electrons prefer to leave. The zinc corrodes leaving an insulating skin of zinc carbonate on its surface which then prevents further corrosion.
A similar concept is used on aluminium which is anodised – a chemical process used to create a dense protective layer of aluminium oxide (corrosion) on its surface.
Another way of reducing corrosion is to make sure that the metals used in contact with each other are the same. Copper, brass, aluminium, steel, etc. if they are exposed to the elements in contact with each other you will usually find that one will start to deteriorate.
You can use stainless steel. By adding alloying materials, particularly chromium, to the steel the structure of the steel is changed to be very stable. The steel forms a very thin layer of chromium oxide on its surface to protect it from further corrosion. I won't bore you with the metallurgical explanation or of the difficulties of working with stainless steel but believe me a good marine grade stainless steel is very rust resistant.
Beware - there are many different types of stainless steel and some are still prone to rusting in the right, or do I mean wrong, circumstances. I have recently come across several stainless steel water tanks that have rusted through.
Ships and steel structures immersed in sea water use sacrificial anodes made of magnesium or zinc. Electrons don't much like those. The whole point is to make the electrons flow out of the anode and not the steel and so stop the steel from rusting. The sacrificial anodes corrode in preference to the steel. Once the sacrificial anodes are exhausted they must be replaced or the steel will start to rust.
As I have said in previous articles your electric water heater and solar hot water heater have sacrificial anodes inside the water storage tank to stop it rusting the steel of the tank. When the sacrificial anode is exhausted your water heater is living on borrowed time I'm afraid.
There is another clever method of stopping immersed steel from rusting known as cathodic protection. It is commonly used on steel oil rigs. We apply a very low voltage to cancel out the electrical activity that corrodes the steel. It can be amazingly effective. I once inspected some steel piles in the Red Sea where the electric current had been too high. The current had forced the paint coating off the steel leaving shiny bare metal sitting in salt water. I do hope I am not boring you with my metallurgical drivel.
Rust is a constant problem particularly on an island surrounded by sea with those wonderful salt laden breezes. Here in Bali we have all manner of steel that is exposed to these breezes, air conditioner units, steel boxes for electricity switch panels, ceiling fans, pumps, steel manhole covers and water heaters.
If you are close to the sea you need to consider corrosion as an ongoing maintenance problem. Here are some ideas:
Install stainless steel ceiling fans. Be careful and make sure they are stainless steel, there are many fans around that look like stainless but are plated steel and will rust.
Think about using stainless steel for electricity boxes and manhole covers.
Consider installing covers on water heaters, pumps and air conditioner units to protect them but make sure that air conditioners have vents where they are needed for the fan.
Situate external steel items on walls out of the way of prevailing winds, I saw a house recently with air conditioners totally rusted out on one side while they were still in excellent condition on the other.
Some air conditioner manufacturers produce external units with a high quality paint finish to resist corrosion.
After 5 years consider checking the sacrificial anodes in your water heaters.
Don't use corrugated iron near the sea.
Galvanise the steel or use stainless steel for external frames, balustrades, security grills and structures.
Where possible use marine grade 316 stainless steel.
Remember Canute? He was that king who centuries ago tried to control the sea and ended up getting his feet washed to say nothing of egg on his face and a dubious place in history. Relax, go with the flow and if the frustration of a battle with the sea and its corrosive effects starts to get at you consider moving inland. You didn't really want to live by the sea did you.
Phil Wilson
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