All language subtitles for S03E02 - Combination Locks; Pottery; Recreational Vehicles; Erasers (576p AMZN WEB-DL x265 Garshasp)_track4_[eng]

Narrator:
Today on "How it's made"...

...Combination locks...

...Pottery...

...Recreational vehicles...

...And erasers.

Combination padlocks
Are what students depend on

To protect their lockers
From thieves and pranksters.

Combo locks are functional
Yet fashionable.

Like everything else marketed
To teenagers these days,

They come in a variety
Of trendy colors and designs.

The combination lock's
Main locking mechanism

Is called the baseplate,

And it's comprised
Of seven components.

That black piece,
Called the lock bolt,

Is what slides open
To free the shackle

When someone dials
The correct combination.

They rivet the baseplate
Components into place

So the lock will stand up
To repeated use.

Here are those components
Before assembly and after.

They secure the assembled
Baseplate into the casing.

Then they install
The trip-lever spring.

It's what automatically
Scrambles the mechanism

Every time the lock is closed.

They fit the shackle
Through holes in the casing,

Positioning one end
Against the trip lever.

They fasten the other side

With a tiny steel bar
Called a yoke.

The lock's combination function

Is made up of three
Stacked disks called tumblers.

Here, the first two go in.

Next, they grease the shackle

So it will slide in and out
Easily.

Sometimes they customize
The face of the lock.

Those numbered dials
Used to come

In just boring
Standard-issue steel.

Today, they can have
Colorful designs --

Even a school's logo.

The printing machine uses
A four-color printing process,

Applying one color at a time.

The painted dials get two coats
Of clear varnish

To harden and protect the paint.

While that's happening,

Other workers assemble
The dial components.

First they take
The indicator button

And attach it to the dial.

Then they take the third tumbler

And rivet it
To the back of the dial.

This tumbler will control

The movement
Of the two other tumblers

Inside the lock's casing.

All three tumblers have
"V"-shaped indentations.

The correct combination
Aligns those v's,

Allowing the lock bolt to slide
Over and free of the shackle.

Each tumbler has a code number
Stamped on the back.

The number corresponds to
The location of its indentation.

They program each lock's
Three tumbler codes

Into a computer.

The computer then randomly
Creates a combination

That will align
The three indentations.

There are more than 50,000
Possible combinations.

The system prints
The combination on a sticker

Along with a bar code.

The bar code is programmed
Into a central computer,

Where it's recorded
With the lock's serial number.

The guts of the combination lock
Are finished.

Now it's time
For the final assembling.

They put the dial
Onto the casing.

Then a forming tool presses down
On the casing's rim,

Folding it tightly
Over the dial.

A computer-guided machine

Then engraves a serial number
On each lock.

Some factories do random
Quality-control checks,

But this company verifies

Each and every combination lock
By hand.

That's quite the procedure,

Considering this plant produces
More than 10,000 locks a day.

You can bet somebody's got
Pretty sore fingers

By quitting time.

Narrator:
As early as 11,000 b.C.,

Man was making utensils
Out of clay.

This was the birth of pottery.

Modern pottery is divided
Into three categories --

Porcelain, stoneware,
And earthenware.

What differentiates them

Is the mixture of clays
And the firing process.

This earthenware piece starts
With a technical drawing

Based on an artist's conception.

Following the specs,

They use a series
Of specialized tools

To sculpt a plaster model
On an electric potter's wheel.

They check the diameter
With calipers.

The model is 7% larger
Than the finished piece will be

To compensate for shrinkage

That will occur
During drying and firing.

They sculpt some parts by hand
And glue them on.

Using this model,
They cast a master mold,

Made out of a rigid type
Of plaster called gypsum.

They now use this master mold
To cast a production mold

Out of rubber
Or, in this case, plaster.

First they pour in the plaster,

Using their hands
To break up any air bubbles

That would cause defects
In the casting.

The leave it to air-dry
In a warm room overnight.

Once it's ready,
They can extract it --

A delicate operation
That takes 15 minutes.

This production mold has to cure
For 48 hours

Before going into service.

It will be good
For 200 castings.

And it will be identified
By the model number on its side.

Earthenware is made of talc,

A mineral called
Nepheline syenite,

A dark-beige clay
Known as ball clay,

Another mineral
Called silicon,

And a white clay
Known as kaolin,

All mixed with 40% water.

They pour the mix
Into the production mold

With careful, even pressure,

Again to avoid
Creating air bubbles.

The plaster mold
Slowly absorbs the water,

Leaving behind
A moist earthenware lining

2/10 of an inch thick.

After about a half-hour,
This lining hardens,

And they can dump out
The surplus liquid.

They cut off the excess
Earthenware at the top...

...Then,
After another 45 minutes or so,

Extract the piece from the mold.

Workers have to handle
The earthenware gingerly

With even pressure.

If one finger presses
Just a bit too hard,

It will show up as a dent,

But only after the piece
Is fired.

After a 24-hour drying period,

Workers then carefully shave off
The seam

Left by the two halves
Of the mold.

They rub the piece
On a wet stone

To even out the top and bottom.

Then they smooth the surface
With a wet sponge.

Unlike stoneware,

Which comes out glossy
After firing,

Earthenware remains dull.

So, to make it
Shiny and colorful,

They apply specialized glazes
And enamel paints.

Finally, they spray the piece
From top to bottom

In a transparent glaze

To give it an overall sheen.

Then it's off to a room-sized
Oven called a kiln

For an eight-hour firing,

During which time
The temperature climbs

To more than
1,800 degrees fahrenheit.

Then a two-hour cooldown.

The intense heat activates
The pigments in the paints

And makes the colors come alive,

Turning what was once a lump
Of clay into a work of art.

Narrator: traveling
In a recreational vehicle

Is like having your own
Personal motel on wheels.

R.V.S are either motorized
Or towable.

Towable ones range
From folding-tent trailers,

Known as pop ups,

To more elaborate
Travel trailers

Complete with fully equipped
Bathrooms and kitchens.

To make a travel trailer,

Workers first cut steel bars
To build a frame.

The saw has to be drenched
In coolant,

Or it will overheat
Due to the intense friction.

They drill holes
For the bolts and screws

They'll later use
To attach certain components.

Then they weld
The frame parts together.

They run electrical wires
Through the frame,

Lining the holes
With rubber grommets

To keep the wires from rubbing
On the sharp metal edge.

Next they install metal brackets

To hold the water
And septic tanks in place

Underneath the trailer.

Then they torque the wheels
To the axle.

Now they install the gas lines.

The stove, the fridge,
And the heating system

All run on propane.

Next come the water
And septic tanks,

Made of polyethylene,
A heavy-duty plastic.

They cut a hole in each tank
And screw on a fitting.

The tank sits directly
On the frame.

The white one's
For drinking water.

The first black one's
For the shower and sinks,

And the second black one's
For the toilet.

To build the floor,

They put down
A waterproof membrane,

Then a spruce frame insulated
With fiberglass wool,

Then 5/8 plywood,

Cutting vent holes for
The forced-air heating system.

After sanding the joints
And gluing down linoleum,

They install the cabinetry
And furniture.

The plumbing fixtures come next.

They connect to water lines

Coming up from the tanks
Beneath the floor.

The water system is driven
By an electric pump.

While some workers put up
The preassembled walls,

Others run wiring for lights
And appliances.

The inside wall surface
Is vinyl paneling.

Drywall would be far too heavy
For an r.V.

The paneling's mounted
On a pine structure

Insulated with fiberglass wool.

They cover the outside
In aluminum siding,

Then they complete
The electrical wiring

For the lights and appliances.

Now it's time
To install the roof --

Another pine structure
With fiberglass-wool insulation

Covered with a thin wood
Called lauan

That's reinforced

To withstand the extra weight
Of roof cargo.

They cut out the various
Ventilation holes...

...Then apply a layer of glue...

...Then lay down

A high-performance
Waterproof rubber membrane...

...Nailing it down
Along the perimeter.

They install vents
For the toilet,

The refrigerator,
And for air circulation.

They caulk all the joints
And around all the vents.

Last but not least --

The windows, doors, awnings,
And any optional equipment.

Workers check the water, gas,
And electrical systems,

Then do what's called
A seal test.

A special machine
Applies air pressure

From the inside out.

Wherever water bubbles,
There's a leak to be repaired.

With all the upholstery

And other decorative elements
In place,

This comfortable travel trailer
Is ready to hit the road.

Narrator:
Make no mistake about it --

An eraser is
A student's best friend.

Whether it's attached to the top
Of a pencil or on its own,

Only an eraser
Can quickly rub out an error.

White erasers are made
Of flexible vinyl,

While pink erasers are made
Of synthetic rubber.

In 1736, a french explorer

Observed south american
Native indians

Using a certain tree resin
To make bouncing balls.

He brought this resin back home,
And before long,

Europeans discovered it could
Rub out lead pencil marks,

Hence the term "Rubber."

There was just one problem --
After a while, rubber would rot.

That dilemma was solved
A century later

By one charles goodyear,

Who developed a curing process
To keep rubber from rotting.

A lot of ingredients go into
Making a simple pink eraser --

Carefully measured fillers,
Accelerators,

Curing agents, oils, coloring,

And the main ingredient --
Synthetic rubber.

They start by putting
A batch of rubber into a mill.

The rubber passes repeatedly
Between large heated rollers.

They throw in
Any defective erasers

From the last production run,

Recycling them
Into this new batch.

Then they add sulfur
As a curing agent,

Accelerators
To help the sulfur do its job,

And red coloring.

They blend everything
For 5 to 10 minutes

Until the mixture is
The consistency of heavy dough.

Next,
Vulcanized vegetable oil --

That's vegetable oil
Treated with sulfur.

Then regular vegetable oil.

Then calcium carbonate
As a filler.

When the color and thickness
Are just right,

Workers remove the rubber,

Which, by now, is hot and soft
As a result of all that milling.

They leave it to cool and harden
At room temperature

For about half a day.

When the rubber's ready,
They cut out large squares,

Each weighing
Between 11 and 18 pounds,

Depending on the thickness of
Eraser the client has ordered.

The squares go into
A steam-heated press to cure

For about 20 minutes
At 325 degrees fahrenheit.

The pressure compacts
The rubber,

While the intense heat
Hardens it.

They trim off the excess

Then submerge the hot
Rubber squares in cold water

To stop the curing process.

To make erasers that erase
Both lead and ink,

They cut beveled strips
From two batches of rubber,

One pink and one blue.

The blue contains pumice,

Which gives it extra
Abrasiveness to erase ink.

They pair up each pink
With a blue

To form a two-color strip.

Then it's into the steam press.

After 12 minutes,
Workers remove the trays,

Trim off the excess,

And submerge the strips
In cold water

To stop the curing process.

Then an automated machine
Chops the strips

Into pieces the size of erasers.

Now back
To the all-pink erasers.

The rubber squares come out
Of their cold-water bath

And go through a machine

That cuts strips
With beveled edges...

Then chops the strips
Into erasers.

From there, the erasers drop
Into a giant barrel.

Workers throw in some talc

To prevent them
From sticking together.

Then they set
The barrel spinning

For three to five hours.

As the erasers tumble
Against each other,

The abrasion rounds off
Their edges.

The last step is printing.

A machine stamps each eraser

With the company name
And the model number.

It's not the rubber that gives
The eraser the ability to erase,

But rather the vulcanized
Vegetable oil that's in it.

That's what makes the eraser
Crumble when rubbed on paper,

Taking away the pencil marks
With it.

--captions by vitac--
Www.Vitac.Com

Captions paid for by
Discovery communications, inc.

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