All language subtitles for S02E09 - Steel Safes; False Teeth; Airplanes; Maple Syrup (576p AMZN WEB-DL x265 Garshasp)_track4_[eng]

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

Steel safes...

False teeth...

Airplanes...

And maple syrup.

The first bank safes

Were made of wood reinforced
With sheet iron.

Thieves would just
Smash them open.

Then came safes
Made of solid iron.

Thieves would just blow them up.

But then, to the crooks' dismay,
Came safes made of steel.

It all starts with sheets
Of solid steel

Up to 1 1/2 inches thick

And an automated machine with
An oxygen-and-gas-fueled flame.

The flame slowly cuts
The plates

That will form the walls
Of the safe.

The cutting creates gases
That are doused with water.

A welder with a manual version
Of the same flame

Frees up the plates
With a few last cuts.

Then, using a large magnet,
They stack the plates.

Each one is labeled

So the workers will know
In what order to assemble them.

They're assembled by a welder

Who uses a machine called
A mig welder.

The welding wire is made
Of several different metals.

It rolls off a spool as needed.

Elsewhere in the factory,

A semiautomatic saw cuts
Flat bars of steel.

These bars will form the frame

That will surround
The steel plates.

Meanwhile, another machine,
Called a turret,

Fashions steel bars
Into moving parts

For the locking mechanism
And also into hinges.

That milky liquid
Is a lubricant.

Normally, you see raw material
Move on an assembly line

From tool to tool.

This is just the opposite.

The steel bar stays on
The turret from start to finish.

The tools come and go.

Workers take pieces of sheet
Metal cut into shapes by laser

And bend them in a press to make
Various parts and mechanisms.

Meanwhile, the large steel
Plates they cut earlier

Go into a hydraulic press
To make them perfectly flat.

It's finally time to put
All the components together.

They construct the frame
In an assembly jig,

Then insert the plates
For the sides, top, and bottom.

Using the mig welder again,
They fuse the pieces together.

They measure the angles,

Then use a giant clamp
To square the safe.

Finally, they install the plate
For the back of the safe

And weld the joints.

They stand the safe upright

And grind down the welding lines
Until they're smooth.

This factory also produces
What's called a composite safe,

Made of soft materials
Such as copper, aluminum,

And low-grade steel.

But it has a cement core,

Making this safe
Harder to break in to.

The finished safe gets
Three coats of paint.

Then, in the finishing
Department,

They install the mechanical
Or electronic locks

And locking mechanisms,

As well as the internal
Time-lock mechanism.

The time lock allows access
To the safe

Only at certain times of day,

Such as a bank's business hours.

Even if someone picks
The outside combination locks,

The door won't open
Outside those set hours.

Narrator: the machines that
Sterilize medical instruments

Use ethylene oxide,
A highly toxic gas.

Now there's a new method

That's safer, more effective,
And less expensive.

This new machine uses ozone
As the sterilizing agent.

Ozone is a form of oxygen.

Until the 1800s, false teeth
Were made of animal bone, ivory,

Or actual human teeth.

They came from poor people,
Who sold their teeth,

And from dead bodies.

Today's dentures
Are usually ceramic.

They start by heating
A sheet of wax over a flame.

They press it
Onto a rough plaster model

Of the patient's mouth,

Sent in by the dentist.

The lab technicians use
This model

To prepare what's called
An impression tray,

What the dentist will use
To make a rubber mold

To cast the dentures.

They apply an acrylic material
Over the wax lining,

Forming a handle so they'll be
Able to remove it afterwards.

Once the acrylic hardens,

They pull it out of the model
And discard the wax.

The dentist fills this
New acrylic tray with rubber

To take a final impression.

The lab uses the hardened rubber

As a negative mold
Of the patient's mouth.

They fill it with plaster

To make a new,
More precise plaster model.

Then they use the new model
To make the part of the dentures

That fits on top
Of the patient's gums.

They take special
Orthodontic acrylic

And press it into the model

To form what's called
The baseplate.

Then they heat a sheet of wax
To form a rim on the base.

This new acrylic-and-wax model

Now goes back for another
Fitting in the patient's mouth.

The dentist takes a series
Of measurements

To show the lab exactly
Where to place the teeth.

The model goes back to the lab,

Where technicians select
The teeth

That'll best suit the size
Of the patient's mouth.

They install the teeth one by
One into the model's wax rim.

Then they send the model
Back to the dentist

For the final fitting.

The dentist checks
That everything is centered

And that the patient's bite
Is properly aligned.

If the model fits well
And looks good,

The lab can finally begin
To manufacture the dentures.

They position the model in
A special holder called a flask,

Then attach channels

Through which acrylic
Will later be injected.

This acrylic will replace the
Wax holding the teeth in place.

But first,
To get rid of the wax,

They have to cast a plaster mold
To hold the teeth in place.

Once the plaster dries,

They submerge it in hot water
For five minutes

To melt the wax inside.

They rinse the plaster mold
With warm water

To remove any wax residues.

Then they apply what's called
A separator,

A chemical
That will keep the acrylic

From sticking
To the plaster mold --

Just like greasing the pan
When you're baking.

They position a cylinder of
Acrylic right over the flask.

Using an air-pressure piston,

They force the acrylic
Into the plaster mold.

They submerge the mold in
Boiling water for 35 minutes

To harden the acrylic.

Once the flask has cooled down,
They break the plaster.

The false teeth are now securely
Rooted in acrylic gums.

A bit of finishing,
And they'll be done.

An ultrasonic bath gets rid
Of any remaining plaster.

They polish the acrylic
With pumice,

Then shine it up
With a polishing compound.

The set of false teeth
Is finally ready.

When a patient doesn't need
A full set of dentures,

Just a few teeth,

They get what's called
A partial --

Made much the same way,

But hooked on at either end
To the patient's natural teeth.

Narrator: aviation was once
The exclusive domain

Of commercial
And military pilots.

Not anymore.

Today many amateurs get
Their pilot's license

And take to the skies
In light aircraft

Not for a job, but for the sheer
Pleasure of flying.

To construct the body
Of these light aircraft,

They start
With two types of cloth,

One woven from glass fibers --
Fiberglass --

The other from carbon fibers.

Carbon is a chemical element
That's stronger than steel.

Both materials go through
A laminating machine

That coats them
With an epoxy resin.

To begin forming the various
Parts that make up the body,

Workers lay strips of
The laminated fabric into molds.

The engineering plans dictate

The precise positioning
Of the strips,

Which is critical
For strength and durability.

They lay in carbon-fiber cloth

Where they need to have
Extra strength

Without additional weight,

Areas such as this --

The passenger compartment
Of the cockpit.

To make the fuselage,

They sandwich a foam core
Less than 1/2 inch thick

Between two layers
Of the fiberglass cloth.

The foam also insulates
Against heat, cold, and noise.

Workers coat the edges
And joints with resin,

Filling any voids.

Once all the fabric
Is in the mold,

It's time to vacuum-bag it.

First, they cover everything

With a layer
Of perforated plastic,

Then with a breather cloth,

Which looks like
A white wool blanket.

Then comes another layer
Of plastic.

They attach a vacuum
To suck out all the air.

The excess resin exits through
The tiny holes in the plastic

And soaks
Into the breather cloth.

Now that the mold is airtight,
It can begin to cure.

They put it into an oven at
40 degrees celsius for 8 hours.

Once the molds come
Out of the oven,

Workers install
The internal structure.

Then, using the same epoxy resin
They used earlier

To laminate the fiberglass
And carbon-fiber fabrics,

They bond the tail's upper
And lower shells together.

They do the same
With the wings.

The parts are left to cure
Overnight.

The next day, they finally come
Out of the molds.

Next stop, the trim shop.

Workers remove
The excess fiberglass

And cut out the windows.

The parts go back
For a final curing.

The oven is around 175 degrees.

18 hours later,
Out they come for painting.

Workers sand the parts and coat
Them with an epoxy primer.

The finish coat is polyurethane,

Which resists weathering.

Meanwhile,
Other workers assemble

And test various components,

Such as the electrical system.

A computer guides a machine
To cut all the metal parts,

Such as the instrument panel.

The cutting machine
Doesn't have a blade,

But rather a sand-and-water jet

That's powerful enough
To cut through metal.

A certified aircraft welder
Prepares the engine mount,

The base that will hold
The engine in place.

It's made
Of high-grade carbon steel.

At the final assembly stage,
Workers install the engine

And other previously assembled
Components into the fuselage.

Workers position the wiring
And plumbing,

Then hook them up.

They screw on the wing tips,

Which already have
Their navigational lights.

An avionics technician powers up
The airplane for the first time

To function-test everything.

The final inspection takes place
Where it really counts --

In flight.

Narrator:
How do maple trees make sap?

They accumulate starch
During their growing season.

With the spring thaw, enzymes
Transform the starch into sugar.

When the trees absorb water
Through their roots,

It mixes with that sugar
To make sap.

Long before the white man
Came to north america,

The native indians revered
The maple tree.

In early spring, they'd pierce
Its trunk with a tomahawk,

Then place a wood chip
Under the hole

To channel the sap
Into a bark container.

Then they boiled the sap
Over a fire in clay pots.

The indians introduced maple
Syrup to the european settlers.

Today most producers use tubing
Instead of sap buckets --

No more trudging through
The snow from tree to tree.

The time to collect sap
Is in the early spring,

When the maple trees
Are still dormant

And when the temperature hits
3 or 4 degrees above freezing.

The freeze-and-thaw cycle alters
The pressure inside the tree

And starts the sap flowing.

The first step
Is to tap the trees.

They drill a hole 1/2 inch
In diameter,

2 inches deep,

Then gently insert a spout
Made of metal or plastic.

It's important not to damage
The bark.

That not only harms the tree

But also lets air in the sap,
Which ruins the flavor.

You don't see too many
Sap buckets around anymore.

Today sap is pumped
Through polyethylene tubes

To larger collector tubes...

Then into the pumping station.

Sap is 97.5% water
And only 2.5% sugar.

To transform the sap to syrup,

They have to boil it down.

It takes 35 gallons of sap

To make just one gallon
Of syrup.

When the tank fills up,

The sap is automatically pumped
To the sugar house

Into a stainless-steel tank.

The more advanced producers use
A specialized machine

That partially concentrates
The sap by reverse osmosis.

This more than triples
The sap's natural sugar level

And means they'll have
Less boiling to do.

From there, the sap flows
To the evaporator.

They heat the sap
To the boiling point

And keep it boiling
However long it takes

To evaporate 66% of the water.

If the water evaporates
Too slowly or too quickly,

That'll adversely affect
The color, flavor, and texture

Of the syrup.

However -- and here's where
Expertise is everything --

There's no set cooking time.

Experienced
Maple-sugar producers

Can tell when it's ready
Just by looking at it.

They test the sugar level using
A device called a hydrotherm.

When the syrup is just right,

They run it through
A pressure filter

To remove calcium residues
And other impurities.

They store the syrup
In steam-cleaned barrels.

The lab at the central warehouse
Tests a sample from each drum.

Using sophisticated instruments,

Technicians classify the color
From dark to extra light.

They also assess the quality.

Lower-grade syrup
Is for industrial use,

Higher-grade
For the retail market.

They pasteurize the syrup,

Then put it into huge
Stainless-steel storage tanks.

The tanks are vacuum-sealed
With a nitrogen barrier

To preserve the flavor and color
And to prevent fermentation.

It also keeps the syrup
From crystallizing.

The lab then uses an instrument

Called an atomic absorption
Spectrophotometer

To analyze the syrup's
Mineral content,

Making sure it meets
Market standards.

Next, they warm the syrup
In stainless-steel heaters...

...And run it through
Industrial-sized filters.

This step ensures the syrup
Will be perfectly clear.

Then, just before bottling,
They heat the syrup again,

This time to 180 degrees.

This not only sterilizes
The bottles

But also guarantees the syrup
Will have a 4-year shelf life.

Maple syrup is high in sugar

But has somewhat fewer calories
Than honey or brown sugar.

It's 100% pure and natural,

And it's a good source
Of three essential nutrients --

Calcium, potassium,
And magnesium.

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

Captions paid for by
Discovery communications, inc.

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