12x12 - Escalators/Kevlar Canoes/Goat Cheese/Disc Music Boxes

[bunniefuu]

Narrator: every day,

Millions of people
around the world use escalators

In places like shopping malls
and airports.

Escalators can move 100 or more
people just as easily as 1.

Driven by a motor,
these moving stairways

Make it very convenient
for people to get around.

Riding an escalator is easy,

But building the smoothest
and most quiet ride possible

Takes expertise.

It starts
with workers welding together

The structural framework
of the escalator.

Like the chassis of a car,

The track system
and all other components

Will be bolted to this frame.

A worker puts together
the main drive gear,

Which hooks up to a motor
with a chain.

It will pull the steps
and the handrails.

He puts on
an emergency-brake device

And uses bolts
to secure it in place.

He attaches side frames
to the gear

To make what is called
the transition assembly.

This assembly includes
a drive gear for the handrail

And allows the steps
to loop back

At both ends of the escalator.

He then lowers the completed
transition assembly

Into the truss -- the hollow
structure of the escalator.

With the transition assembly
in place,

Workers then install
a comb plate --

The last part of the escalator
a person steps on

Before getting onto
the moving steps.

A worker makes the steps
using aluminum ingots,

Which he puts into a crucible.

They then apply a release agent

To the mold
used to make the steps.

Spraying more lubricant
on the mold

Ensures the aluminum stair
will release properly

From the die-cast machine,

Which automatically receives

The exact amount
of molten aluminum needed

To make one step.

A robot then takes the one-piece
step from the die-cast machine

And carries it
to the trimming department.

Here, a trim press
removes some residual aluminum.

The excess material goes back
to the crucible to be recycled.

Once the robot finishes
a general trimming of the step,

It sends it
to the finishing department.

There, finishing robots
then file off the sharp edges.

The robot also files
in between the teeth

That go across the step.

Then it passes the step
over a belt sander,

Making it smooth to the touch.

Transformed from solid aluminum

To a casting
that is painted and assembled,

The step is now ready
to be installed.

A worker rolls out a chain
of rollers called a step chain.

He greases all the pins.

Then they place all the steps
into position.

Workers then connect
the axles on the steps

To the pins in the step chain

And then lock them together
using a spring clip.

They feed the required length of
chain and steps into the unit.

A worker then attaches
a turnaround track.

The turnaround track
allows the length of steps

To make a continuous loop

From one end of the escalator
to the other.

The escalator runs
for about five hours

To ensure it operates
quietly and properly.

During this testing period,

It goes through up to 250
quality-control checks.

After passing all the tests,

Workers wrap the unit
in heat-shrink plastic.

The escalator is now ready
to load on a flatbed truck

For delivery to the customer.

Narrator:
your canoe may well be made

Of the same material they use
to make bulletproof vests.

That's right.

Many canoes today
are made of woven aramid fibers,

Better known
by the trade name "kevlar."

For canoes, though,
they use a lesser density,

Since, presumably,
no one will be sh**ting at you.

A kevlar canoe

Weighs about half as much
as a wooden or aluminum canoe,

And it's virtually
maintenance-free.

They build these canoes from
several layers of kevlar fabric

Glued together to create
a solid laminate material.

It all begins with a fiberglass
mold of the canoe's hull.

The first step is to spread
resin over its interior.

Once that's done,

They spread a sheet of kevlar
over the resin

And rub it against the mold
to push out any air bubbles.

Then they trim off
the excess fabric.

Using a squeegee,
they force out any excess resin

And stretch the fabric
until it's taut.

This step ensures the laminate
will turn out strong and smooth.

They repeat this entire process
with a second layer of kevlar,

Then run a roller
over everything

To expel any excess resin

And press the layers
tightly together.

Now for
some structural components.

Pieces of thin high-density foam
go along the bottom of the hull.

Glue bonds them to each other
and to the bottom of the hull.

Using a machine
called a hot box,

They begin heating
strips of foam to curve them.

These curved pieces
are called ribs.

They reinforce the sides,
adhering with resin.

With the structural core
of the canoe complete,

They now encase it
in a third layer of kevlar.

Once that's down,

They prepare to bond everything
together with vacuum pressure.

They lay down
a sheet of white fabric

Impregnated
with a nonstick coating

To prevent the vacuum bag
from sticking to the surface.

This mesh, called scrim,
goes on next.

It helps stimulate airflow
during that vacuum process.

Now they tape a plastic
vacuum bag around the mold,

Sealing everything inside.

Then they connect one end
of a hose to the bag

And the other end
to a vacuum machine.

The vacuum steadily draws out
the air from within the bag,

Pulling the layers of kevlar
tightly together.

After 8 to 10 hours
under vacuum, the bag comes off.

If a canoe flips over,

Flotation tanks in the corners
keep it afloat.

Workers build each tank out of
two pieces of low-density foam.

After sanding them
to the right shape,

They lay a sheet
of fiberglass mat over them

And coat it with resin.

This strengthens the foam

And seals the two pieces
into one unit.

After the resin cures
for an hour,

They extract the canoe
from the mold.

The factory's quality-control
inspector checks it over

And, if everything's okay,

Applies a protective coat
of resin.

Once that's dry,

They cap the edges with
aluminum strips called gunwales,

Which keep the hull
from folding inward...

Then an aluminum crossbeam

And a nylon end cap
on each end...

A wooden yoke for carrying
the canoe upside down on land

And a wooden seat
with nylon webbing.

Workers rivet all these
components to the gunwales,

Then rivet the gunwales
securely to the kevlar laminate.

This factory puts every canoe
it produces on a digital scale

To ensure it meets
weight specifications.

If all is well,
the finishing touch is a decal

Displaying
the manufacturer's name.

Kevlar canoes, like those
made of other materials,

Vary in size, shape, and design.

A canoe intended for fishing
or hunting, for example,

Is quite different than one
designed for long expeditions

Or for a two-person racing team

Or for a solo canoeist.

Narrator:
goat cheese tastes tarter
than cheese made from cow's milk

Because goat's milk
has a higher proportion

Of certain fatty acids,
which sharpen the flavor.

There are hard and soft
varieties of goat cheese.

The soft ones are usually sold
in logs or disks

And often have a coating
of peppercorns, chopped herbs,

Or other flavorings.

The texture of soft goat cheese

Makes it ideal
for spreading on crackers

Or crumbling
over pasta or salads.

Goat cheese
is also called "chèvre,"

The french word for "goat."

Farmers start breeding goats
when the animals are a year old.

Their gestation period
lasts five months,

Meaning milk production begins

At the age
of about a year and a half.

The goats go for a milking
every 12 hours or so.

The first step is to manually
squirt some milk into a cup

To check the quality.

If it looks good, they wipe
the teats with disinfectant

To remove surface bacteria.

Then they hook up
the automated milk extractor.

A milking takes
just two or three minutes.

It typically yields


At the cheese factory,
the goat's milk

Goes into a steam-heated
pasteurization tank.

An agitator stirs the milk
nonstop to keep it from cooking.

They heat the milk
to 66 degrees celsius,

Which kills off any bacteria.

With the milk now pasteurized,
they add bacterial cultures.

These kick-start
the fermentation.

Then they add rennet.

Diluted in water,

Rennet is an extract
from calf stomachs.

It contains enzymes
which curdle milk.

With the cultures and rennet in,

Workers now let the milk ferment
for 18 hours.

The result -- cheese curds
and a watery liquid called whey.

They ladle out the curds

And put them in a
cheesecloth bag to strain them.

As they lift the bag,
the sheer weight of the curds

Forces out
much of the remaining whey.

They tie up the bag

And let the curds sit
for another 18 hours,

After which time
workers strain them again.

The goat cheese
is finally ready.

They weigh it

And mix in just the right
proportion of salt -- 0.6% --

To slow down the aging process.

One of the formats this factory
produces is 175-gram packages,

So workers weigh out


...then hand-roll each blob
into a ball

Then flatten each ball
into a disk.

The disk goes into refrigeration
until packaging time.

The fridge temperature
is 3 degrees celsius --

Just above freezing.

Some goat cheeses go for a roll
in special flavorings.

These are chives.

Then it's into cellophane wrap
and a plastic container.

On the product label,
they stamp a "best before" date.

Unopened, goat cheese
has a two-month shelf life...

Once opened, about a week.

Another format is log-shaped.

They roll
this particular variety

In a five-pepper seasoning.

Workers also hand-roll
goat-cheese ba*ls.

They go into a container

With spices, sun-dried tomatoes,
and olive oil.

Goat cheese is a healthy food.

It has twice the protein
of cow's-milk cream cheese

Yet half the fat and cholesterol
and 1/3 fewer calories.

Narrator: ipods may rule
in this digital age,

But there's nothing
quite like a melody

That's mechanically generated
by a music box.

It's why, more than a century
after its heyday,

The music box
still holds a special appeal.

Its musical chimes
take us back to another time.

[ Soft music plays ]

A revolving disk,
swirling dolls,

And luxurious cabinetry --

The music box is the original
home-entertainment system.

Today, they make
these authentic replicas

With computerized tools.

They contour a gear
for this spring-wound motor

And then carve teeth into it.

This gear is similar
to the type used in clockworks.

It's a windup device.

Next, they coil
a 20-foot-long strip of steel

Into a little cast-iron barrel.

This is called a spring barrel,

And it's the device that stores
the wound-up mechanical energy.

Once the clutch is installed,

It will be ready
to spring into action.

This circular blade
now sculpts the weights

That extend from the base teeth
of the musical comb.

The weights are called leads,

And they help produce
the low notes.

To tune the base, a technician
snips the ends of the leads.

She plucks a tooth
to produce a note,

Then measures its pitch with
an electronic-tuning machine.

She adjusts it
by clipping off a bit more.

This process is critical.

It ensures each of the 76 teeth
on the musical comb

Will hit all the right notes.

There's a damper for each tooth
to quell its vibration.

They install these dampers on a
rail next to the star wheels --

The part that plucks the teeth
of the comb to produce notes.

The technician aligns
the dampers to the star wheels

And bolts everything
to a cast-iron plate
called the bedplate.

Using a pincers-like tool,

He checks the tension of the
dampers and makes adjustments.

Now he secures the upper comb
to the bedplate

And turns it around
to install the lower comb.

Music boxes with two combs
instead of one

Have a richer sound.

The technician makes
more adjustments to the dampers

To ensure a proper gap

Between them and the teeth
of the musical comb.

He installs the bar
that holds down the music disk

While it plays,

Then he bolts the motor frame
to the side of the cabinet,

Followed by the winding
and disk-drive gears.

He attaches the spring barrel
to the gears.

Here, he installs
a speed-control mechanism

For the winding gears.

It's called the "governor"
because it governs the speed.

He winds the motor
to power it up for a test run...

...and then checks all its parts

To confirm
the motor operates smoothly.

When he's satisfied
that it does,

It's time to install
the musical components,

Beginning with the soundboard,
which amplifies the notes.

Next, the bedplate,
with its double-comb assembly,

Is mounted onto the soundboard.

He screws support brackets
to the box.

They'll prop up
the musical disk.

He checks the setup
with a dummy disk.

On a real disk, music is printed
in the form of perforations.

This master disk
serves as a template

To punch holes
in a copper-plated disk below.

The punctures form curls
in the underside of the disk,

And it's these metal curls that
will set the music in motion.

[ Clicking ]

As the windup motor
turns the disk,

Those curls
snag the star wheels.

[ Soft music plays ]

The star wheels, in turn, pluck
the teeth of the musical comb.

The music isn't digital,
but it's truly magical.

The music box is one technology
that stands the test of time.

If you have any comments
about the show,

Or if you'd like to suggest
topics for future shows,

Drop us a line at...