The Secret Life of Machines (1988) s01e04 Episode Script
The Washing Machine
1 [Door opens, footsteps.]
[Creak!.]
[THUD!.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[vacuum cleaner noise.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[TV static noise.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[Steam hisses.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[sewing machine rattles.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[Whoop!.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
Tim: Most people take their washing machine for granted, except for the occasional outburst of hatred, when the thing goes wrong.
But in fact they're wonderful feats of human ingenuity.
Although they're now so commonplace it's taken an enormous amount of time and effort to perfect their design.
Only 30 years ago, automatics were rare expensive luxuries.
And 70 years ago there were only the most primitive hand-operated machines.
[birds tweeting.]
[people humming.]
All washing depends on squashing water through the fibres of the fabric.
[person hums, pants and splashes.]
Soap helps to dislodge the dirt and carry it away in the lather.
The first step towards mechanisation was the dolly.
This was pummeled up and down in the washtub.
and avoided the needed to get quite so wet, and also the need to bend down.
From this, in the late 18th century, various hand operated washing machines were patented.
In fact these hand operated machines continued to be made until well into the 20th Century.
This one's called the Eddy and it actually works quite well [rattling noise.]
The backwards and forwards action stops the clothes getting tangled, and the paddles bash the clothes just hard enough to wash them, but not so hard that it tears them to bits.
[quiet rattling.]
An early more radical departure from hand-washing had been used by sailors for centuries.
[noise of waves.]
[wooosh.]
[splosh.]
The combination of agitation and a constant flow of clean water washed them fairly effectively, even without soap.
[footsteps.]
[whoosh!.]
[waves and rustling fabric.]
Another way of forcing water through the clothes, is to make them tumble over each other in a drum.
The earliest record of a machine of this type dates from 1782.
This was the forerunner of much larger laundry machines, that rotated the drum and heated the water with steam.
[laundry noise.]
In many respects laundry machines have remained unchanged, with the clothes tumbling over each other in a large drum.
But although 140 years ago the basic principles of industrial machines had been perfected, domestic machines remained extremely primitive.
The arrival of reasonably small electric motors at the beginning of the 20th Century, made a large number of washing actions possible.
[patriotic music.]
These early machines were particularly popular in America, where they were viewed with great pride.
[music continues.]
[rattly motor noise.]
This machine was imported from Canada to Britain in the 1920s.
The motor sits underneath, connected by a system of belts and gears.
[rattly motor noise.]
It's really rather a splendid contraption.
[motor off.]
Inside there's a paddle that goes backwards and forwards, very much the same shape as the old washing dolly.
These machines had a very serious disadvantage, that they often leaked quite a bit, and the motor, the water used to drip down on the motor, and the switch and all the wires.
And because water's a conductor, the whole machine could easily become live.
I mean, I've just got a little shock off this.
Safety was quite an important reason for enclosing the whole machine in a single case like this, with motor and wires and tub all in one.
The first machines like these, looking a bit like a modern washing machine, appeared in the mid 1930s.
The water still had to be heated in a separate wash-boiler.
[typewriter keys.]
Woman: How's it coming Lyn? [rattle of sheet removal.]
So there I was at 20,000 feet.
Tim: The idea of a fully automatic washing machine came from America [women continue to chatter.]
The first ones appeared in the 1920s.
but it was another 30 years or so before they started to become practical labour saving devices.
Woman: Brother, get this Carol! Carol: Hmm? Middle: What does the emancipation of American women mean to you? Lyn: I know! Women's right to vote! That's the biggest thing that's happened to women since Woman: Since Adam's apple! Woman: Carol, you sweet dumb thing, pull up your flaps, you're dragin'.
[washing machine starts to humm.]
Carol: Oh my gosh, that's a terrific angle! Talk about emancipation, take the family wash for instance! No more clotheslines! No more dark basements! No more blue Mondays! Boy! Here's real emancipation from old fashioned chores! Just set a dial, and walk away.
That's the kind of emancipation any woman can understand.
Tim: The first automatics appeared in Britain in the 1950s, imported from America.
These machines were extremely expensive, costing as much as a small car.
And most households still had no washing machine at all.
Then in the early 1960s, this machine appeared.
It wasn't fully automatic; it had separate wash and spin tubs.
But it was, compared to all its competitors, amazingly cheap.
Voiceover: Which twin tub should you buy? Independent tests show Rolls as good value for money.
So if you want a twin-tub that's good and quick for washing.
easy to use, electrically safe, good value for money and also gives up to a maximum of £35 in part exchange, then you must choose a Rolls.
Yes, a Rolls.
For full details of the Rolls Concorde models, and this week's special offers, fill in the Rolls coupon in today's papers, now! Tim: The Rolls company, owned by John Bloom, went bankrupt in 1964, but by that time had enormously expanded the market for washing machines.
Well, so much for the history.
But how does a modern machine actually work? Well, Rex Garrod and I have made a series of models and demonstrations.
to explain some of the mysteries of what's inside a modern washing machine.
Well one of the first things you notice when you take the top off, is often an enormous lump of concrete.
Rex: On this machine we've taken those large blocks of concrete out, so you can see exactly what happens [washing machine starts up.]
[spins up to high speed.]
[loud thunking noises.]
Tim: The concrete's there to damp out the machine's vibrations.
well every structure or machine has natural resonant frequencies, at which vibration can become excessive.
Occasionally this can be useful, as I'll show you.
This is a thunder machine.
I made it for a theatre company.
[motor rotates quietly.]
The eccentric weight on the motor is a bit like the washing in the drum which is never completely balanced.
[thunder noise starts and gets louder.]
The noise is created entirely by a vibration, the weight never actually touches the steel plate.
[thunder noise continues.]
[large laundry machine motor.]
In industrial laundry machines the effect is much greater, and older machines had to be bolted to the floor with massive foundations.
Modern laundry machines don't vibrate nearly so much.
They automatically balance the load, by pumping different amounts of water into the triangular pockets round the drum.
The lights show which pockets are being filled.
[water sloshing.]
[machine whirring.]
Of course domestic machines aren't so sophisticated and have to make do with their lumps of concrete.
And if you chop a modern machine in half You realise what a vast number of bits and pieces there are.
And of course each one of them could go wrong in all sorts of ways.
The real miracle is that most of them work perfectly all the time.
the first thing that happens when you turn the machine on is that water gushes in, released by a sort of electric tap called a solenoid valve.
[click.]
[water runs.]
[click.]
Simply pass the current through it, and the valve opens.
The clever thing about these valves is it's just a small cylinder, and a small coil.
And it has to resist the full force of mains water pressure.
So I have to actuall push my finger over the end quite hard, to stop the water coming out.
Whoops! giggles Ahem! And er, it does this by using the pressure of the water itself to stop the water coming out.
This part is the solenoid, a sort of electromagnet.
The steel piston in the middle is attracted by the magnetism, and pulled in when the current is switched on.
The piston rests on the centre of a rubber disc, which acts as the seal.
In this disc, there are two tiny holes.
The hole in the side lets water into the space above the disk.
and then the water pressure itself keeps it down.
When the current is passed, the piston uncovers the centre hole and lets some water leak out.
This lowers the pressure above the disk and lets it pop up and the water flow through.
[laudry noise.]
[workers chatting.]
Today, solenoid valves have millions of uses controlling liquids and gasses.
[laundry noise continues.]
For instance, the ironing machine in the laundry uses solenoid valves to release blasts of compressed air to blow the sheets flat.
Each sheet hits a switch which opens the valves at precisely the right moment.
[hissing of compressed air.]
[machine noise.]
[more compressed air.]
Rex: A more spectacular use for a solenoid valve, is to roll a car for a stunt, for a film or television.
We got the solenoid valve fitted on top of this tube, which is, in effect, a cannon and inside the tube is a large chunk of wood, which pushes the car over.
In the boot of the car, we've got a compressed air cylinder, full of air, at quite high pressure, about 150 pounds per square inch.
And when I press the button, which is attached to the hand brake lever, that releases all the air through the solenoid valve, push against the wood, and 'woosh' away we go! It's far better fun than a washing machine solenoid! A stunt like this is carefully planned, so as hardly anything ever goes wrong.
And of course I'm tied into that seat.
It's so painfully tight with special, sort of aircraft-type seatbelts.
It's so tight it actually hurts me.
But you can't afford to move an inch or so, because the impact when you roll over really does hurt.
As soon as the car starts to roll, all the electric is cut as to avoid any fire.
There's only a pint of petrol on board, so that if the thing did catch fire that's a very minor fire.
[Engine roars.]
[boom crash etc.]
Rex: I'm okay! This is the actual canon piston, which does the damage, which pushes it over.
So you can see it's really crude, just a piece of car inner tube to seal it on the walls of the cylinder so that when the air comes through, it pushes it out.
It doesn't need a lot of energy to tip it, because it's almost on the point of turning before you hit the button.
[engine roars.]
[piston fires.]
[crash bang etc.]
Rex: That's the last one I'll ever do.
I promised that to everybody.
This is the second time I've promised not to do it again.
chuckles Until the next job comes along.
In this cut-away machine, you can see the position of all the parts we've been looking at.
There's the lump of concrete.
There are the solenoid valves where the water comes in through the soap dispenser and into the drum.
And this is the pressure switch.
Water is gushing into the machine through the solenoid valve.
and when it reaches the right level it's got to stop.
And that's what the pressure switch is for.
I can show it more clearly using this bottle to replace the washing drum.
So we turn the water on [water runs.]
And we've added some dye in here, to make it a bit more clear what's happening.
And the switch has switched the water off.
Well now what's actually going on is that air is trapped inside this little bottle on the side and as the level rises the air is being squashed and actually increasing the pressure down this little pipe, into the switch.
I think I can show this, prove this, quite clearly by It has exactly the same effect if I blow into the switch, as the little bottle on the side.
So if I release the pressure [click - water runs.]
the water will start coming out, and when I blow into it [water stops.]
[click - water starts again, and stops as Tim blows into pipe.]
Hmm.
Just turn it off now [click.]
Well what's going on inside this switch is This is one we've er, a similar size, a slightly different make, but the same sort of thing.
We've taken it, in half.
In this half the air goes in here and there's a rubber disc here.
[quiet whistling noise.]
And as the pressure increases the rubber expands.
On this half the rubber pushes the metal and flicks over the switch.
Well pressure switches, like solenoid valves have all sorts of uses.
I used one on this machine, which I made years and years ago.
Erm, put the [coin clatter.]
[loud motor noise.]
[BANG!.]
[Motor whirrs down.]
Well, the pressure switch is used on this machine, to switch the motor off when the balloon bursts.
Inside here, there's a small secondary tube which goes down to the pressure switch at the back.
And as long as there's the pressure inside the balloon, the motor will keep running, but when the balloon bursts, the pressure drops and that turns the motor off.
Once the washing machine's full of water the heater comes on to get it to the right temperature.
You never see the heater elements because they're outside the inner drum.
But they're just like the elements inside an electric kettle.
We cut one in half here, and in the middle there's a fine wire, and it's this wire that carries the current.
And closely packed around it, there's this white powder, magnesium oxide.
This is an electrical insulator, to stop the outer casing becoming live.
This white powder is obviously the same as the powder you get when you burn a bit of Magnesium.
It's used because it retains its stability and insulation at the high temperatures inside the element.
At the same time as the water starts hating up, the wash action starts.
[whirring of washing machine motor.]
The speed that the drum goes round is critical.
The clothes just have to get round to the top then fall, and that's what squashes the water through them.
After going one way round, they pause and then go back round the other way.
this stops clothes getting tangled up, just like in the Eddy.
Once the wash has finished, the next stage is the spin.
[motor noise.]
[motor speed increases rapidly.]
Tim: But this apparently simple idea is quite recent, [music.]
and early machines used much more elaborate ways to dry the clothes.
[music continues.]
Woman: I must get this done quickly.
Tim: The mangle, which squeezed clothes dry, had considerable disadvantages.
[poing.]
Oppps! [water sloshing.]
Woman: this new machine looks a lot better.
Tim: The collapsible rubber drum was even less successful.
Woman: Lets see.
Oh No! It's STILL wet! Ohhhh.
Tim: The principle of the spin-drier is that water is forced outwards.
Just like you're forced outwards on the fairground ride The Rotor.
Well, in this model here, we've taken the outer casing off a spin drier, so you can see what's, what actually goes on.
In this sort, the water comes out of these slits in the middle.
Well, if I er, get out of the way.
I'll switch it on [motor slowly speeds up.]
[water sprinkles.]
This is actually part of a separate spin-drier, but the automatic uses the same principle.
[machine slows down.]
Tim: The water is flung into an outer drum, from there it's then pumped out the bottom.
The pump usually has a separate small motor, beneath the drum, which is connected up here.
Inside the pump, the water comes in through the middle and the impeller whizzes round and round and forces the water up, out, outwards.
Up through the waste hose.
The ingenious thing about these pumps is that they resist blocking themselves up, with fluff and other small objects.
It does this because the impeller is much smaller than the space around it.
I think we can show you, er, how it helps, how it tries not to block itself up, with this model If you start the pump going and tip some buttons into the drum [clatter.]
[running water.]
They all go straight through the pump.
The central part of any automatic is the programmer-timer, which switches everything on and off at the right moment.
These devices had an unlikely origin.
[music.]
[Rock and roll music.]
The first automatic was made by an American company called Seaberg, who mostly made jukeboxes.
In some respects, the automatic washing machine does have more in common with a jukebox than with a primitive electric washer.
Both the automatic and jukebox have timers switching a sequence of operations.
Seaberg's washing machine was a failure, but it carried on making programmer timers for other companies.
[music continues.]
The modern washing machine timer is totally enclosed.
It's a lot easier to see how it works with an industrial equivalent where everything is much more spaced out.
This is a small switch, called a microswitch.
And there are a whole row of them along the back here.
And at the end here there's a geared motor.
As the motor rotates it turns this drum round with these cams on, and these switch the microswitches on and off.
[clicking of microswitches.]
Each switch is connected to a different function of the machine.
Of course, on a washing machine, it goes round much slower; one revolution for the complete wash cycle.
I quite often use these times, because a lot of the machines I make have a sequence of actions.
This one's called the chiropodist, she looks down at your foot for a bit and then looks up and twiddles her thumbs.
Then she disappears beneath her counter, and tickles your foot.
[people giggling.]
[annoying music.]
In the past few years, microprocessors have started to replace electromechanical timers.
It hasn't been easy to make a microprocessor work reliably inside the hot and steamy environment of a washing machine.
And it's only quite recently, after years of development, that they've become a practical alternative.
The principle of the modern automatic has changed very little in the last 25 years, except the main difference is the price, which, adjusted for inflation, is less than half what it was.
[baby babbles.]
Repair Man: What seems to be the trouble sir? Man: I've just got dirty washing everywhere Tim: But to make this reduction in price possible, the machines have changed a lot inside, and they're no longer built to last forever.
The modern engineering would probably horrify pre-war engineers, who worshipped quality and not economy.
Repairman: Oh, look at that engineering! Oh God! Ohhhh! [Baby babbles.]
Man: Oh dear.
Oh dear [clank crash bang.]
Man: Uh.
oooh.
Tim: Most of these changes have gone unnoticed.
The old automatics like the climatic, had complete separate chassis inside.
In the modern machines, all the bits are just bolted to the outer casing.
The old machines had cast iron weights, whereas the modern machines have their lumps of concrete.
In the old machines the heater wires were about twice as thick as they are now.
And the pulleys, which used to be solid lumps of cast iron, are now often just really tin cans full of concrete.
[washing machine noise.]
It's tempting to think that washing machines don't last so long as they used to simply because they're less well made.
There's some truth in this, but it's also a result of the manufacturer's great success at cutting their costs.
It's now much often cheaper to buy a whole new machine, than it is to pay for even a simple repair.
All the machines you've seen in this programme were scrap, they cost us about £2 each and they came from household waste tips.
I hate today's disposable way of making things in all sorts of ways, but I can't help but admire the ingenuity of the modern washing machine.
I hope I've managed to convey some of my enthusiasm for these ingenious contraptions.
[washing machines run.]
[Jazzy music: 'Take 5' - Dave Brubeck.]
[Creak!.]
[THUD!.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[vacuum cleaner noise.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[TV static noise.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[Steam hisses.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[sewing machine rattles.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
[Whoop!.]
[Jazzy music: 'The Russians Are Coming' - Val Bennett.]
Tim: Most people take their washing machine for granted, except for the occasional outburst of hatred, when the thing goes wrong.
But in fact they're wonderful feats of human ingenuity.
Although they're now so commonplace it's taken an enormous amount of time and effort to perfect their design.
Only 30 years ago, automatics were rare expensive luxuries.
And 70 years ago there were only the most primitive hand-operated machines.
[birds tweeting.]
[people humming.]
All washing depends on squashing water through the fibres of the fabric.
[person hums, pants and splashes.]
Soap helps to dislodge the dirt and carry it away in the lather.
The first step towards mechanisation was the dolly.
This was pummeled up and down in the washtub.
and avoided the needed to get quite so wet, and also the need to bend down.
From this, in the late 18th century, various hand operated washing machines were patented.
In fact these hand operated machines continued to be made until well into the 20th Century.
This one's called the Eddy and it actually works quite well [rattling noise.]
The backwards and forwards action stops the clothes getting tangled, and the paddles bash the clothes just hard enough to wash them, but not so hard that it tears them to bits.
[quiet rattling.]
An early more radical departure from hand-washing had been used by sailors for centuries.
[noise of waves.]
[wooosh.]
[splosh.]
The combination of agitation and a constant flow of clean water washed them fairly effectively, even without soap.
[footsteps.]
[whoosh!.]
[waves and rustling fabric.]
Another way of forcing water through the clothes, is to make them tumble over each other in a drum.
The earliest record of a machine of this type dates from 1782.
This was the forerunner of much larger laundry machines, that rotated the drum and heated the water with steam.
[laundry noise.]
In many respects laundry machines have remained unchanged, with the clothes tumbling over each other in a large drum.
But although 140 years ago the basic principles of industrial machines had been perfected, domestic machines remained extremely primitive.
The arrival of reasonably small electric motors at the beginning of the 20th Century, made a large number of washing actions possible.
[patriotic music.]
These early machines were particularly popular in America, where they were viewed with great pride.
[music continues.]
[rattly motor noise.]
This machine was imported from Canada to Britain in the 1920s.
The motor sits underneath, connected by a system of belts and gears.
[rattly motor noise.]
It's really rather a splendid contraption.
[motor off.]
Inside there's a paddle that goes backwards and forwards, very much the same shape as the old washing dolly.
These machines had a very serious disadvantage, that they often leaked quite a bit, and the motor, the water used to drip down on the motor, and the switch and all the wires.
And because water's a conductor, the whole machine could easily become live.
I mean, I've just got a little shock off this.
Safety was quite an important reason for enclosing the whole machine in a single case like this, with motor and wires and tub all in one.
The first machines like these, looking a bit like a modern washing machine, appeared in the mid 1930s.
The water still had to be heated in a separate wash-boiler.
[typewriter keys.]
Woman: How's it coming Lyn? [rattle of sheet removal.]
So there I was at 20,000 feet.
Tim: The idea of a fully automatic washing machine came from America [women continue to chatter.]
The first ones appeared in the 1920s.
but it was another 30 years or so before they started to become practical labour saving devices.
Woman: Brother, get this Carol! Carol: Hmm? Middle: What does the emancipation of American women mean to you? Lyn: I know! Women's right to vote! That's the biggest thing that's happened to women since Woman: Since Adam's apple! Woman: Carol, you sweet dumb thing, pull up your flaps, you're dragin'.
[washing machine starts to humm.]
Carol: Oh my gosh, that's a terrific angle! Talk about emancipation, take the family wash for instance! No more clotheslines! No more dark basements! No more blue Mondays! Boy! Here's real emancipation from old fashioned chores! Just set a dial, and walk away.
That's the kind of emancipation any woman can understand.
Tim: The first automatics appeared in Britain in the 1950s, imported from America.
These machines were extremely expensive, costing as much as a small car.
And most households still had no washing machine at all.
Then in the early 1960s, this machine appeared.
It wasn't fully automatic; it had separate wash and spin tubs.
But it was, compared to all its competitors, amazingly cheap.
Voiceover: Which twin tub should you buy? Independent tests show Rolls as good value for money.
So if you want a twin-tub that's good and quick for washing.
easy to use, electrically safe, good value for money and also gives up to a maximum of £35 in part exchange, then you must choose a Rolls.
Yes, a Rolls.
For full details of the Rolls Concorde models, and this week's special offers, fill in the Rolls coupon in today's papers, now! Tim: The Rolls company, owned by John Bloom, went bankrupt in 1964, but by that time had enormously expanded the market for washing machines.
Well, so much for the history.
But how does a modern machine actually work? Well, Rex Garrod and I have made a series of models and demonstrations.
to explain some of the mysteries of what's inside a modern washing machine.
Well one of the first things you notice when you take the top off, is often an enormous lump of concrete.
Rex: On this machine we've taken those large blocks of concrete out, so you can see exactly what happens [washing machine starts up.]
[spins up to high speed.]
[loud thunking noises.]
Tim: The concrete's there to damp out the machine's vibrations.
well every structure or machine has natural resonant frequencies, at which vibration can become excessive.
Occasionally this can be useful, as I'll show you.
This is a thunder machine.
I made it for a theatre company.
[motor rotates quietly.]
The eccentric weight on the motor is a bit like the washing in the drum which is never completely balanced.
[thunder noise starts and gets louder.]
The noise is created entirely by a vibration, the weight never actually touches the steel plate.
[thunder noise continues.]
[large laundry machine motor.]
In industrial laundry machines the effect is much greater, and older machines had to be bolted to the floor with massive foundations.
Modern laundry machines don't vibrate nearly so much.
They automatically balance the load, by pumping different amounts of water into the triangular pockets round the drum.
The lights show which pockets are being filled.
[water sloshing.]
[machine whirring.]
Of course domestic machines aren't so sophisticated and have to make do with their lumps of concrete.
And if you chop a modern machine in half You realise what a vast number of bits and pieces there are.
And of course each one of them could go wrong in all sorts of ways.
The real miracle is that most of them work perfectly all the time.
the first thing that happens when you turn the machine on is that water gushes in, released by a sort of electric tap called a solenoid valve.
[click.]
[water runs.]
[click.]
Simply pass the current through it, and the valve opens.
The clever thing about these valves is it's just a small cylinder, and a small coil.
And it has to resist the full force of mains water pressure.
So I have to actuall push my finger over the end quite hard, to stop the water coming out.
Whoops! giggles Ahem! And er, it does this by using the pressure of the water itself to stop the water coming out.
This part is the solenoid, a sort of electromagnet.
The steel piston in the middle is attracted by the magnetism, and pulled in when the current is switched on.
The piston rests on the centre of a rubber disc, which acts as the seal.
In this disc, there are two tiny holes.
The hole in the side lets water into the space above the disk.
and then the water pressure itself keeps it down.
When the current is passed, the piston uncovers the centre hole and lets some water leak out.
This lowers the pressure above the disk and lets it pop up and the water flow through.
[laudry noise.]
[workers chatting.]
Today, solenoid valves have millions of uses controlling liquids and gasses.
[laundry noise continues.]
For instance, the ironing machine in the laundry uses solenoid valves to release blasts of compressed air to blow the sheets flat.
Each sheet hits a switch which opens the valves at precisely the right moment.
[hissing of compressed air.]
[machine noise.]
[more compressed air.]
Rex: A more spectacular use for a solenoid valve, is to roll a car for a stunt, for a film or television.
We got the solenoid valve fitted on top of this tube, which is, in effect, a cannon and inside the tube is a large chunk of wood, which pushes the car over.
In the boot of the car, we've got a compressed air cylinder, full of air, at quite high pressure, about 150 pounds per square inch.
And when I press the button, which is attached to the hand brake lever, that releases all the air through the solenoid valve, push against the wood, and 'woosh' away we go! It's far better fun than a washing machine solenoid! A stunt like this is carefully planned, so as hardly anything ever goes wrong.
And of course I'm tied into that seat.
It's so painfully tight with special, sort of aircraft-type seatbelts.
It's so tight it actually hurts me.
But you can't afford to move an inch or so, because the impact when you roll over really does hurt.
As soon as the car starts to roll, all the electric is cut as to avoid any fire.
There's only a pint of petrol on board, so that if the thing did catch fire that's a very minor fire.
[Engine roars.]
[boom crash etc.]
Rex: I'm okay! This is the actual canon piston, which does the damage, which pushes it over.
So you can see it's really crude, just a piece of car inner tube to seal it on the walls of the cylinder so that when the air comes through, it pushes it out.
It doesn't need a lot of energy to tip it, because it's almost on the point of turning before you hit the button.
[engine roars.]
[piston fires.]
[crash bang etc.]
Rex: That's the last one I'll ever do.
I promised that to everybody.
This is the second time I've promised not to do it again.
chuckles Until the next job comes along.
In this cut-away machine, you can see the position of all the parts we've been looking at.
There's the lump of concrete.
There are the solenoid valves where the water comes in through the soap dispenser and into the drum.
And this is the pressure switch.
Water is gushing into the machine through the solenoid valve.
and when it reaches the right level it's got to stop.
And that's what the pressure switch is for.
I can show it more clearly using this bottle to replace the washing drum.
So we turn the water on [water runs.]
And we've added some dye in here, to make it a bit more clear what's happening.
And the switch has switched the water off.
Well now what's actually going on is that air is trapped inside this little bottle on the side and as the level rises the air is being squashed and actually increasing the pressure down this little pipe, into the switch.
I think I can show this, prove this, quite clearly by It has exactly the same effect if I blow into the switch, as the little bottle on the side.
So if I release the pressure [click - water runs.]
the water will start coming out, and when I blow into it [water stops.]
[click - water starts again, and stops as Tim blows into pipe.]
Hmm.
Just turn it off now [click.]
Well what's going on inside this switch is This is one we've er, a similar size, a slightly different make, but the same sort of thing.
We've taken it, in half.
In this half the air goes in here and there's a rubber disc here.
[quiet whistling noise.]
And as the pressure increases the rubber expands.
On this half the rubber pushes the metal and flicks over the switch.
Well pressure switches, like solenoid valves have all sorts of uses.
I used one on this machine, which I made years and years ago.
Erm, put the [coin clatter.]
[loud motor noise.]
[BANG!.]
[Motor whirrs down.]
Well, the pressure switch is used on this machine, to switch the motor off when the balloon bursts.
Inside here, there's a small secondary tube which goes down to the pressure switch at the back.
And as long as there's the pressure inside the balloon, the motor will keep running, but when the balloon bursts, the pressure drops and that turns the motor off.
Once the washing machine's full of water the heater comes on to get it to the right temperature.
You never see the heater elements because they're outside the inner drum.
But they're just like the elements inside an electric kettle.
We cut one in half here, and in the middle there's a fine wire, and it's this wire that carries the current.
And closely packed around it, there's this white powder, magnesium oxide.
This is an electrical insulator, to stop the outer casing becoming live.
This white powder is obviously the same as the powder you get when you burn a bit of Magnesium.
It's used because it retains its stability and insulation at the high temperatures inside the element.
At the same time as the water starts hating up, the wash action starts.
[whirring of washing machine motor.]
The speed that the drum goes round is critical.
The clothes just have to get round to the top then fall, and that's what squashes the water through them.
After going one way round, they pause and then go back round the other way.
this stops clothes getting tangled up, just like in the Eddy.
Once the wash has finished, the next stage is the spin.
[motor noise.]
[motor speed increases rapidly.]
Tim: But this apparently simple idea is quite recent, [music.]
and early machines used much more elaborate ways to dry the clothes.
[music continues.]
Woman: I must get this done quickly.
Tim: The mangle, which squeezed clothes dry, had considerable disadvantages.
[poing.]
Oppps! [water sloshing.]
Woman: this new machine looks a lot better.
Tim: The collapsible rubber drum was even less successful.
Woman: Lets see.
Oh No! It's STILL wet! Ohhhh.
Tim: The principle of the spin-drier is that water is forced outwards.
Just like you're forced outwards on the fairground ride The Rotor.
Well, in this model here, we've taken the outer casing off a spin drier, so you can see what's, what actually goes on.
In this sort, the water comes out of these slits in the middle.
Well, if I er, get out of the way.
I'll switch it on [motor slowly speeds up.]
[water sprinkles.]
This is actually part of a separate spin-drier, but the automatic uses the same principle.
[machine slows down.]
Tim: The water is flung into an outer drum, from there it's then pumped out the bottom.
The pump usually has a separate small motor, beneath the drum, which is connected up here.
Inside the pump, the water comes in through the middle and the impeller whizzes round and round and forces the water up, out, outwards.
Up through the waste hose.
The ingenious thing about these pumps is that they resist blocking themselves up, with fluff and other small objects.
It does this because the impeller is much smaller than the space around it.
I think we can show you, er, how it helps, how it tries not to block itself up, with this model If you start the pump going and tip some buttons into the drum [clatter.]
[running water.]
They all go straight through the pump.
The central part of any automatic is the programmer-timer, which switches everything on and off at the right moment.
These devices had an unlikely origin.
[music.]
[Rock and roll music.]
The first automatic was made by an American company called Seaberg, who mostly made jukeboxes.
In some respects, the automatic washing machine does have more in common with a jukebox than with a primitive electric washer.
Both the automatic and jukebox have timers switching a sequence of operations.
Seaberg's washing machine was a failure, but it carried on making programmer timers for other companies.
[music continues.]
The modern washing machine timer is totally enclosed.
It's a lot easier to see how it works with an industrial equivalent where everything is much more spaced out.
This is a small switch, called a microswitch.
And there are a whole row of them along the back here.
And at the end here there's a geared motor.
As the motor rotates it turns this drum round with these cams on, and these switch the microswitches on and off.
[clicking of microswitches.]
Each switch is connected to a different function of the machine.
Of course, on a washing machine, it goes round much slower; one revolution for the complete wash cycle.
I quite often use these times, because a lot of the machines I make have a sequence of actions.
This one's called the chiropodist, she looks down at your foot for a bit and then looks up and twiddles her thumbs.
Then she disappears beneath her counter, and tickles your foot.
[people giggling.]
[annoying music.]
In the past few years, microprocessors have started to replace electromechanical timers.
It hasn't been easy to make a microprocessor work reliably inside the hot and steamy environment of a washing machine.
And it's only quite recently, after years of development, that they've become a practical alternative.
The principle of the modern automatic has changed very little in the last 25 years, except the main difference is the price, which, adjusted for inflation, is less than half what it was.
[baby babbles.]
Repair Man: What seems to be the trouble sir? Man: I've just got dirty washing everywhere Tim: But to make this reduction in price possible, the machines have changed a lot inside, and they're no longer built to last forever.
The modern engineering would probably horrify pre-war engineers, who worshipped quality and not economy.
Repairman: Oh, look at that engineering! Oh God! Ohhhh! [Baby babbles.]
Man: Oh dear.
Oh dear [clank crash bang.]
Man: Uh.
oooh.
Tim: Most of these changes have gone unnoticed.
The old automatics like the climatic, had complete separate chassis inside.
In the modern machines, all the bits are just bolted to the outer casing.
The old machines had cast iron weights, whereas the modern machines have their lumps of concrete.
In the old machines the heater wires were about twice as thick as they are now.
And the pulleys, which used to be solid lumps of cast iron, are now often just really tin cans full of concrete.
[washing machine noise.]
It's tempting to think that washing machines don't last so long as they used to simply because they're less well made.
There's some truth in this, but it's also a result of the manufacturer's great success at cutting their costs.
It's now much often cheaper to buy a whole new machine, than it is to pay for even a simple repair.
All the machines you've seen in this programme were scrap, they cost us about £2 each and they came from household waste tips.
I hate today's disposable way of making things in all sorts of ways, but I can't help but admire the ingenuity of the modern washing machine.
I hope I've managed to convey some of my enthusiasm for these ingenious contraptions.
[washing machines run.]
[Jazzy music: 'Take 5' - Dave Brubeck.]