04x02 - Plastic Injection Moulds/Automotive Oil Filters/Filing Cabinets/Blown Glass

[bunniefuu]

Narrator: if you take a closer
look at the products around you,

You'll notice
that many are made of parts

That have been
assembled together.

One way factories
make product parts

Is by melting material such
as metal, rubber, or plastic,

Then pouring or injecting them
into molds.

To make a plastic part
for a product,

The manufacturer has to first
commission a mold-making company

To design and produce
a plastic-injection mold.

The mold begins
as bars of chromium steel,

A highly durable metal
that can withstand

Repeated high-pressure injection
of plastic.

Workers assemble several bars
into a block called a mold base.

They mount this base
on a milling machine,

Which shaves the bars
to the right dimension.

This step is critical, enabling
them to later machine the base

Into a mold that's true
to the technical design,

Right down to
the hundredth of a millimeter.

A mold usually consists
of two halves,

Each of which is comprised
of several components.

The factory drills strategically
positioned holes in each base

For the guide pins and bushings

That hold
the components together

When the plastic's injected.

A grinder now goes to work,

Smoothing
and leveling all surfaces.

This prepares the base

For the high-precision
machining operations

That will transform it
into a mold component.

A computer-guided
tooling machine called the cnc

Slowly machines the base,

Wearing away the steel,
particle by particle,

To create
the mold-component shape.

This one, part of a mold

For the plastic rim around
a snowmobile's front headlight,

Takes 20 hours to complete.

From here, most mold components

Go on to
a second tooling machine,

Especially if they require
fine detailing

That this cnc machine
isn't capable of carving.

The second machine is outfitted

With a copper electrode in
the shape of the plastic part,

In this case,
a snowmobile oil gauge.

After polishing the electrode
to ensure flawless casting,

They use a sophisticated
measuring device

To verify the dimensions.

The electrode goes facedown

On the second tooling machine,
called the edm.

Directly underneath
is the mold half

That's been partially formed
on the first machine.

A strong electric current runs
through the electrode

And penetrates the mold,

Forming a cavity in the shape
of the electrode.

After tooling,
they drill coolant lines.

This is for
the cooling fluid they'll use

To accelerate the hardening
of the molten plastic.

Some plastic product parts,

Like that snowmobile oil gauge
we saw earlier,

Have lettering on them.

The factory engraves the letters
in reverse

Inside the mold cavity.

After the plastic's injected,

The writing is right-side out
and raised.

This surface of the mold cavity

Is pretty rough
from all that tooling,

So they polish it smooth
to ensure proper casting.

Here's what the two halves
of a finished mold look like.

The pins and bushings
fit together

To close the mold

Before injecting
the hot liquid plastic.

Once the plastic
cools and hardens,

It's just a matter of extracting
the molded plastic part.

Here's a different
molding method --

A two-step process
they're using to make buttons

That go on the steering handle
of a jet ski.

First, they mold a structural
base out of hard, white plastic.

Then, they put the base
into a second mold

And inject a rubberlike
gray plastic.

This softer plastic

Covers everything
but the raised lettering,

Giving the button a softer feel.

Factories also make molds

For aluminum injection
and rubber injection,

Among other materials.

They build those molds
from different types of metal

But using the same techniques.

Narrator:
changing your car's oil filter
a couple of times a year

Is an easy way to prolong
the life of your engine.

The oil pump forces oil
through the filter

To the moving parts
in the engine.

The filter's job is
to block dirt and metal debris

From getting in between those
parts and causing engine damage.

They make many oil-filter parts
from steel coil --

A sheet of steel on a roll.

They start by unwinding the roll

And feeding the coil
into a press.

The press contains
a series of dies,

Each of which
progressively stamps the steel

Into the shape of the specific
part they're making.

This press is churning out
tapping plates,

A component
on the end of the oil filter

That screws onto
the car's engine.

Hot off the press,
the tapping plates

Travel on a magnetic conveyer
to the welding station.

There, a robotic arm loads them
onto the welding carrousel.

But before any welding begins,

A nozzle applies sealant
around the rim of each plate.

This will fill any gaps left
between the parts after welding.

A robot
now welds the tapping plate

To another steel part
called the bottom ring.

This ring will hold the gasket,

The rubber seal that prevents
oil from leaking out

As it travels through the filter
into the engine.

The welded parts,
known as the bottom assembly,

Now go onto a machine

That cuts a thread pattern
through the center.

This will enable the oil filter
to be screwed onto the engine.

Another press produces
the oil filter's steel body,

Called the cannister.

The dies first stamp out
a rough cannister shape.

Then, they reduce the diameter
and make the can taller.

Finally,
they cut off the excess.

Elsewhere in the factory,
another machine

Cuts and perforates
pieces of tin-plated steel coil

And rolls them into tubes.

We'll see
where those tubes go shortly.

Yet another machine prepares
the filter's key component --

A filter paper
that works like a fine sieve,

Trapping dirt, carbon, and soot.

First,
the machine pleats the paper

So it will fit
inside the cannister.

Next, the machine cuts

The continuous ribbon
of pleated paper into lengths.

It folds each piece
into a circle,

Fastening the ends
with a steel clip.

The next machine assembles

What's called
the filter cartridge.

It places each filter paper
over a tube.

The tube's job
is to reinforce the paper

Against the force
of the oil pumping through it.

This machine
glues a capping disk

On each end
of the filter paper

To hold the tube in place.

A heater cures the glue.

Now for the final assembly.

As the cannisters go by
upside down,

Automated arms insert
the filter cartridges.

A worker then puts
a thin, rubber disk

On top of each cartridge.

This disk will prevent the oil
from draining out of the filter.

Now for those bottom assemblies
we saw them making earlier.

A worker positions
one on each cannister.

Then, a machine called
a seamer folds its edge down,

Forming a rim,
just like the rim of a soup can.

Now the conveyer turns
the filters right-side up,

As they file by five nozzles
spraying powder paint.

An infrared oven dries the paint
in about 90 seconds.

Then, a printing machine stamps
on the product information.

The conveyer now turns
the filters upside down again,

As they travel
to the gasket inserter.

Its automated plungers insert
a gasket into each bottom ring.

These automotive oil filters
are finally finished

And ready to do the dirty work.

Narrator: whether you work
in a sprawling corporate office

Or in a home office,

Filing cabinets
are an essential component

Of an efficient workplace.

They keep your paperwork tidy,
organized, and out of sight,

Yet just a drawer away.

And when you're short on space,

They make a handy counter
for the coffee maker.

Filing cabinets begin
as sheets of cold rolled steel,

A thin type of metal that's easy
to bend, weld, and paint.

As the sheet comes off the roll,

It goes through a straightening
machine that removes the curve,

Then, into a press,

Whose dies punch out
the shape of the specific part,

Complete with holes, slots,
and embossments.

A filing cabinet is made up
of over 60 steel parts.

For the top-selling models,

The factory has dies specially
designed to punch out each part.

But that's too costly a system

For models
that aren't mass-produced.

To make low-volume
or custom-made filing cabinets,

The factory uses

This computer-controlled
punching machine.

This equipment operates
at a far slower speed

Than the presses we just saw,

But the advantage is
that it can be programmed

To punch out any size, shape,
or design,

No matter how complex.

Several filing-cabinet parts are
designed to be bent into shape.

Workers do that manually, using
a machine called a press brake.

This particular part will become
the top of the filing cabinet,

So they're making downward folds
along the perimeter

To create 1 1/2-inch-wide edges

With strong
and tight corner seams.

This machine
is called a dedicated bender

Because it only bends
one type of part --

The filing-cabinet doors.

The factory produces doors
in such high volume

That it pays to design
a special machine to shape them.

The doors are also bent downward
along the perimeter

To create edges half-an-inch
wide with tight corner seams.

The cabinet's base is welded

From the same type of steel
sheeting as the other parts.

Small steel reinforcements
make it rigid enough

To support the excessive weight
of file-filled drawers.

To join the cabinet's
side and back,

Robots perform what's called
"resistance welding,"

Fusing metal using heat
from an electric current.

The next set of robots

Welds the side and back unit
to the cabinet top.

After this,

Workers attach the base using
what's called "mig welding" --

Welding that adds extra metal
along the joint

To create a strong seam.

Once again, it doesn't pay

To invest
in robotic welding equipment

For models
that aren't mass-produced.

They manually weld
low-volume items

Such as those small filing
cabinets that roll under desks.

In the paint department,
rotary atomizers

Envelop the filing cabinets
in a mist of paint

That contains a synthetic resin
for durability.

These atomizers
lace the paint particles

With a negative electric charge.

This draws the particles to a
positive charge on the cabinets,

Creating a thorough
and even coat.

After 20 minutes in an oven
to bake the paint,

Assembly can begin.

Ball-bearing sliders
on which the drawers will sit,

Tracks for the fold-down doors,
and doorstops,

So the doors can't be
pulled off their tracks.

There's also a locking system

That simultaneously bolts
both sides of each door,

Making the files inside
inaccessible.

The last step is to install
the doors and drawers

Using a rubber mallet,
so as not to damage the finish.

Each drawer can support
up to 200 pounds of files.

An interlock system lets you
open only one drawer at a time.

This prevents the cabinet
from toppling forward.

Narrator: a glassblower

Can transform a sizzling blob
of molten glass

Into sheer sculpture

Or objects that are
both functional and decorative.

Blowing glass can be on the
cutting edge of modern design,

Quite a feat for an art that's
more than 2,000 years old.

The first hollow glass objects
date back to 1,500 b.c.

The invention of the blowpipe
around 30 b.c.

Revolutionized the craft.

Until then, objects were either
carved from solid glass blocks

Or molded from molten glass.

The blowpipe enabled glassmakers
to expand and shape glass.

It made fast, inexpensive
production possible.

This meant that everyday items,
not just luxuries,

Could now be made of glass,

Accessible not just to the rich
but to the ordinary people, too.

When you see these spectacular
shapes and colors,

It's hard to believe
that blown glass

Comes from
this bland, clumpy stuff.

This is silica, a natural
material derived from sand,

Mixed with thinners
and stabilizers,

Such as potassium
and limestone.

The glassblower recycles
any leftover, colorless glass

Then loads the mix
into the melting furnace.

After 12 hours
at fusion temperature,



The raw material transforms
into colorless liquid glass.

The glassblower uses a blowpipe,

A long steel tube
with a ring or pear-shaped end

To collect
what's called a gather,

A glob of this
red-hot molten material.

To color the gather,

She quickly rolls it
in finely ground colored glass.

At this stage, the glass
is honey-like in consistency,

Though it's cooling
and thickening by the second.

She fuses the color layer

By reheating the glass
for a few seconds

In a smaller furnace
called a glory hole.

Next, she rolls the glass
against a ladle-shaped block

To form a starting shape
for blowing.

A gentle blow or two
bulges it into a hollow bubble.

By now, the cooling glass

Has thickened
to the consistency of caramel,

Making it more controllable
and shapable.

The glassblower stretches
and shapes the glass

With different blocks
and hand tools.

Now the glass
is like hardened caramel,

And it will hold
its final shape.

She scores the glass
where it meets the blowpipe,

Then cools it down further
with compressed air.

On the opposite end of the
glass, with a bit of hot glass,

She attached a solid-metal
maneuvering rod called a pontil.

Then she applies a single drop
of cold water on the score line

To break the glass
off the blowpipe.

Using another pontil,

She plugs the resulting hole
with hot glass.

Then, it's back to the melting
furnace to attach a gather.

It's critical
to always rotate the glass

So that it doesn't droop
and become lopsided.

The glassblower
shapes this gather,

Not with a block, but by hand.

She protects herself
from the intense heat

By using a thick stack
of soggy newspapers.

Using an ordinary pair
of scissors, she forms ridges.

Then, she twists the ridges
to spiral them.

She cools and hardens
the finished design

Using compressed air.

Then, it's a quick blast
into the glory hole

To equalize the temperature
throughout the piece.

This blown-glass lemon reamer

Has taken
all of eight minutes to make.

Now it goes into an electric
kiln for a slow 12-hour cooldown

To prevent cracking.

Meanwhile, the glassblower
starts a new piece --

A large vase.

More blowing, more shaping.

Then, while her co-worker
blows air

To expand the glass
and thin it out,

She cools the vase's bottom
with wet newspapers.

This holds the shape

While she scores
the cutoff point at the top.

After reheating the glass
to resoften it,

They stretch it,
lengthening the vase.

Once they finalize the shape,

They use a wooden paddle
to flatten the base.

Now for some
eye-catching decoration --

Vivid colored glass coiled
like taffy over the entire vase.

Certain designs require

Cutting off a portion
of the finished piece.

That leaves a rough, opaque edge

They must extensively grind
and polish.

A lemon reamer, a vase,
even a mortar and pestle --

A glassblower's work
is clearly remarkable.

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