18x02 - Industrial Wire Ropes/Living Walls/Large Format Cameras/Gemstones

[bunniefuu]

Narrator:
industrial machines

Often have heavy loads
to lift or pull.

Whether
it's a dragline excavator

Working in an open-pit mine,

An oil-drilling rig,
a construction crane,

Or farm machinery,

The weight is borne
by ultrastrong wire ropes.

Industrial-wire ropes

Typically range from 8/10" to 5"
in diameter.

Besides machinery applications,

They also serve
as support cables

For large static structures,

Such as bridges
and stadium roofs.

Manufacturing a wire rope
begins with steel wire

That's anywhere from 3/1,000"
to 3/10" in diameter.

The first step is to wind
several of these wires together

Into a strand.

How many wires per strand

Depends on the job
the rope will perform,

Because different applications

Require different degrees
of flexibility and strength.

Each wire is spooled
onto a steel bobbin

And loaded
onto a stranding machine,

Which is essentially
a giant winder.

There can be as many
as 64 wires in a strand,

Although the typical range
is between 19 and 36.

The twisting wires
converge in a die

That forms them
to the required diameter.

Lubrication is critical,

And not merely to help the wires
move smoothly through the die.

It also penetrates within

To allow slight movement
between the wires.

This increases their life span

And prevents the strand
from seizing.

The strand exits the machine
saturated in lubricant.

A large rubber band skims
the excess off the surface.

The strand now travels
through a row of straighteners.

These heavy rollers
apply vertical pressure,

Effectively erasing
the wire's memory

Of being spooled on a bobbin
prior to stranding.

This prevents the wires
from unraveling.

This cross-section

Shows all the wires
inside the finished strand.

The clothespin gives you
a sense of its size.

Wire strands are by themselves

Typically used
as structural support cables.

To make wire ropes used in
machinery and for heavy lifting,

They take several of these wire
strands and wind them together

On a far bigger and stronger
machine called a closer.

They make this particular rope
from six wire strands.

Before the strands
converge in the die,

Rollers pre-shape them
into a corkscrew-like form.

The strands then enter the die,
twisting together over a core,

Which is itself
a small steel-wire rope.

A core at the center
of the cable

Provides additional strength.

This cable's finished diameter
is 3 1/2".

However, there are always
small variations here and there,

So now
four calibration rollers,

Two compressing vertically,
two horizontally,

Correct the cable to the right
diameter all along its length.

The finished cable
winds onto a big steel reel,

Ready for shipping.

The factory tests random samples
in its quality-control lab.

There, a machine measures
the tensile strength --

How much pulling force
the cable can withstand.

The machine pulls the cable
at both ends until it snaps.

[ Cable snaps ]

For this mega cable,
the breaking point was 104 tons.

To pass the test, a cable

Must exceed the tensile strength
it's designed to withstand.

For certain demanding
applications, such as mining,

Wire ropes
are double-coated in plastic

To protect
against wear and tear.

To prepare the plastic,
the factory

Mixes a recipe of clear
and colored plastic pellets.

An extrusion machine heats
the pellets until they liquefy,

Then forces the molten plastic
through a die,

Coating the rope
as it passes through.

As the rope
exits the extrusion machine,

It passes through water,

Which cools and hardens
the hot plastic.

The plastic not only jackets
the rope's surface,

It also provides cushioning
when on the jobsite,

The strands inside rub against
each other as the rope moves.

By reducing wear and tear

On the steel
both internally and externally,

Plastic coating can extend
the life of a rope by up to 50%.

A cable's internal construction

Determines its strength
and flexibility.

A structural one needs to be
strong, immobile, and taut,

So it's a single strand
made of large wires,

Whereas a moving rope
and large machinery

Contains many strands
made of smaller wires.

Narrator: a living wall
is a vertical structure

Covered with fully grown plants.

This green screen
serves many purposes,

Such as hiding an eyesore or
shielding an area for privacy.

Some are installed
in the ground,

While others are mounted
on building facades

And have
integrated irrigation systems.

Living walls
are modular systems.

Each module
contains fully grown plants,

So upon installation,

The green-screen effect
is immediate.

The plants
are hedera helix woerner,

A variety of ivy that's highly
resistant to cold and drought.

In the manufacturer's
greenhouses,

Horticulturalists take cuttings
from the mother plants...

...then cut off the foliage
and separate the leaves,

Leaving each with a small stem.

Then they plant the cuttings
five leaves to a pot.

The soil is a secret recipe

Of organic and
nonorganic materials and feed.

Over the next month
to six weeks,

Each stem
develops a good root system.

Meanwhile, workers
construct a welded frame

Out of high-strength
carbon steel.

The metal is galvanized
so it's rust-proof.

Once the frame is ready,
they take a mat

Made from biodegradable,
recycled coconut husks

And fold it
into a planter box,

Which fits
inside the bottom of the frame.

Two side wires hold the box
securely in place.

An automated machine
fills the box

With the same soil mix
used for the cuttings.

Then the horticulturalists
plant 13 pots of plants.

That's 65 ivies per box.

They wrap the longer stems

Around the uprights
of the frame.

The frames now move
to the greenhouse,

Where they're hooked up
to an irrigation system.

For the next 18 months or so,
the plants grow,

And as they do,
the horticulturalists

Keep wrapping the ends
around the uprights.

This is called
training the plants.

As the plants thicken,

The nursery workers prune them
to promote upward growth.

The factory produces
these green-screen modules

In 3 heights,
ranging from about 3 to 7 feet.

After installation,

The plants can grow on-site
to a total height of 13 feet.

Each frame -- one module
of the living-wall system --

Is 4 feet wide,
making it easily transportable.

At shipping time, workers load
the screens 10 to a pallet

And truck them
to the installation site.

Each module of the system
installs just like a fence.

Workers embed a wooden post

On either side
of where each screen will go

And dig a trench
that's the width and depth

Of the planter box
running in between.

They sit the screen
in the trench,

Then, with
galvanized-steel brackets,

Clip it to the side posts
at the top and bottom.

Then they fill in the gaps
with dirt.

The screens have
a 45-year life expectancy,

And the leaves
remain on them year-round.

This variety
is used on living walls

In europe and warmer regions.

In colder climates,

The manufacturer uses
a hardier species of ivy

That stays green even
throughout harsh, snowy winters.

Narrator:
a large-format camera

Is essentially
great-granddad's camera,

The one with accordion-style
bellows, the big film,

And the curtain
draped around the viewfinder --


With some modern refinements.

For many serious photographers,
the basic concept still clicks.

In an age when cameras
are miniaturized and digitized,

The large-format camera
might seem to be a relic.

But for pros,
it's a creative tool.

The flexible bellows allow
for a wide range of movements

For incredible control
of the image.

Image quality
is another attraction.

This camera uses big sheet film,


Generating big negatives

That don't need to be enlarged
as much during printing,

So the image
has better resolution.

At this factory,

They mold many of the camera's
parts out of plastic.

They inject liquid plastic
into molds,

And the parts quickly solidify.

Other parts are made

Of laser-cut aluminum
and stainless steel.

The camera maker
assembles the base first,

Attaching rails that slide
back and forth for focusing.

The next parts allow
for swing and shift action --

Movements that come in handy
when composing a shot.

He attaches the camera's
molded, plastic body

To the swing and shift assembly.

Next, he assembles
the front part of the camera,

Which holds
the lens and shutter.

It has
a swing and tilt mechanism

For changing
a shot's depth of field.

He slides the lens holder
into place and secures it.

It can be raised and lowered
when composing the shot.

He inserts spirit levels
into the slots

In the front and rear sections
of the camera.

These levels will be used
to check the angle of the shot.

Moving now
to the focusing screen,

It's made of ground acrylic
to diffuse light.

He protects the acrylic from
scratches with a glass plate

And secures the assembly
with stainless-steel clips.

He snaps
the completed focusing screen

To the body of the camera,
where it can be easily switched

From portrait
to landscape position.

He tests the focus mechanism
and confirms it's operational.

He now folds and glues fabric
in an accordion configuration

To create expanding bellows

That will link the front
and rear parts of the camera.

He applies double-sided tape

Around the inner lip
of the folded bellows.

He sticks more double-sided tape
onto a plastic frame...

...and peels away the tape
backing in strategic locations.

He inserts the frame
into the bellows

And aligns it
with the taped inner border.

He then completely peels off
the taped backing

And presses the frame
to the bellows' taped rim.

This frame adds crucial rigidity
to the bellows.

Using more double-sided tape
and adhesive,

He secures
the bellows' accordion

To a larger fabric bag.

Next, he glues plastic flanges
to each end of the bellows.

The flanges are connector pieces
for attaching the bellows

To the front and rear sections
of the camera.

There are two kinds of bellows.

The one with the bag attached

Is usually used with a lens
of short focal length.

An accordion without the bag has
a much longer range of extension

To accommodate a bigger lens.

He now connects the back
of the camera to the front

With the bellows.

They are a flexible link
between the two.

By expanding
or retracting the bellows,

The photographer
can adjust the distance

Between the lens and film
to focus the shot.

Finally, he attaches the lens
to the front of the camera.

It's now ready for a film test.

He loads the film
into the holder.

Normally, this is done
in complete darkness

To prevent exposure of the film.

But he's left the lights on
for our camera.

The film slides into the holder
into the camera back.

And while film still rules
in large-format photography,

There are
now digital camera backs

For photographers
who want instant results

With traditional focus movements
of the bellows camera.

It's all a matter of focus.

Narrator: man has used gemstones
since ancient times.

Genuine gemstones
come from nature --

Minerals, rocks, or even
certain organic materials.

Shaped, cut, and polished

To bring out their colors
and brilliance,

The rarest ones are classified
as precious gems,

The others as semiprecious.

This semiprecious stone
is called blue john.

It's a variety
of the mineral fluorite,

Also known as fluorspar.

While common fluorspar
is cream or white,

Blue john
also has magnificent bands

Of purple, blue, and yellow.

There's only one place in the
world where blue john is found,

And that's in the village
of castleton, derbyshire,

In central england.

The stone comes from a cavern

Located some 55 yards deep
in a hillside.

The miners don't use expl*sives,

Because the stone
is quite soft and brittle

In its natural state,

And blasting
would simply shatter it.

Instead, they use drills

To carefully dislodge pieces
of blue john from the rock wall.

They carry the blue john to the
surface to the mine's workshop,

Where stone processors
manually wash off the clay.

The stone is wet

Due to having been underground
for some 240 million years,

So they put it into an oven
at low heat --



When the stone comes out of the
oven a couple of weeks later,

All its moisture has evaporated.

The dried stone, however,
is still brittle,

So they submerge it
in a bowl of liquid resin,

Then place the bowl
into a vacuum oven

At 176 degrees fahrenheit.

This process
draws out all the air

And forces the resin
deep into the stone's pores.

The stone then goes into another
oven at 122 degrees fahrenheit

For about 12 hours.

This hardens the resin,

Stabilizing the stone so that it
can be worked without crumbling.

To create large items,
such as goblets and bowls,

The workshop's artisans
turn the stone on a lathe.

To avoid fracturing it, they
must work the blue john slowly

And with diamond-tipped tools.

Diamond, being harder
than all other rocks,

Cuts with less force and stress.

To supply jewelry makers,

The mine workshop
saws stones into slices

Using a diamond-edged saw.

At the jewelry workshop,

A gemologist examines the slices
on a light box

To highlight the coloring
and any flaws.

This helps determine
which parts of the slice

Will yield
the most striking gemstones.

Meanwhile, in another part
of the workshop,

A silversmith crafts
the piece of jewelry --

In this case,
a sterling-silver ring

Which will receive
the blue john gemstone.

She bends, then solders together
the ends of the ring's shank,

The part
that encircles the finger.

After grinding
the solder seam flat,

She fuses the top of the ring,
called the setting,

Onto the shank.

Then she polishes the ring and
passes it onto the gemologist,

Who takes a slice of blue john

And, with
a diamond-edged lapidary saw,

Cuts out the gemstone's shape,

Making it slightly larger
than the setting.

Next, she glues on a backing
cut from mother-of-pearl.

Just like the white light

On which the gemologist
examined the blue john slices,

This mother-of-pearl backing

Highlights the colors
in the stone.

Now, using
a diamond-grit grinding wheel,

She shapes the stone
to perfectly fit in the setting.

She applies glue to the setting

And fits the gemstone
snugly inside.

Once the glue dries,

She uses a diamond-grit sanding
belt to smooth down the edges,

Gradually transforming the rough
oval into a sleek dome.

This gem shape
is known as a cabochon.

Finally, she polishes
the entire ring's surface

Until the silver and
richly hued blue john glisten.

Whether it's one of several,
the shape funky or traditional,

A gemstone sure makes
a piece of jewelry rock.

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