32x04 - Table Tennis Tables; Plastic Model Kits; Light Microscopes

[bunniefuu]

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Narrator:
table tennis is more commonly
known as ping-pong.

Folding table-tennis tables

Are popular in homes
and kept outdoors

Because they can be closed up
and rolled out of the way.

These tables can also fold down
on just one side,

Allowing for solo play.

This high-end outdoor
table-tennis table

Has an aluminum bottom

That prevents the tabletop,
called the plate,

From warping or splitting

Due to expansion
and contraction.

A press stamps cups
into a sheet of aluminum.

This pattern creates
nearly equal areas

Both in contact
and out of contact

With the rest of the plate
layers, providing flexibility

To withstand
temperature-related movement.

Each table needs two
embossed aluminum sheets --

One for each half of the plate.

A technician assembles frames
for the plate halves

Out of square extruded
aluminum tubes,

Cut to the lengths and widths
of the plate half perimeter.

An automated milling machine
makes miter cuts,

Which allow the tubes
to be made into rectangles.

Then, the technician
moves the frames

Onto a rotating fixture...

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...and welds
the corners together.

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The frames are inserted
into a brushing machine.

Inside, wire brush rollers
allow the aluminum surface

To become rough.

This helps the components
to adhere to one another.

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Another technician places the
embossed aluminum sheet

Into a rectangular assembly jig.

And adds the
brushed aluminum frame.

A conveyor transfers the jig
to the next station.

Then, the jig connects with

An 8-millimeter-thick sheet
of particleboard,

Made of wood chips and glue.

The board is coated with a
heat-activated adhesive film

On both sides.

At the next station,
an aluminum sheet is placed

On top of the particleboard.

This step completes
the plate component assembly.

Next, the conveyor loads
the jig into a press.

Once 12 jigs have been loaded
onto the press,

It heats to


And compresses them
for about 10 minutes.

This process
activates the adhesive

And bonds the components of
each plate into a single unit --

One framed plate half.

Each plate half goes through
an automated milling machine.

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The machine trims any excess
material from all four sides

To ensure the table won't
have any sharp edges.

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The plate half goes
through a paint machine,

Then into an oven.

The process repeats,
applying a second coat of paint

And a u.v.-Resistant clear coat.

A machine applies paint
through a screen stencil,

Printing the lines
that mark the boundaries

Of the playing surface.

After the paint is dried
in an oven,

A team places the finished
plate half in a cardboard box

And attaches folding legs
to the base.

The factory
mills the legs in-house

Out of high-tensile steel,

Then finishes them
in baked-on paint.

The net,
along with several components,

Are packed and made in-house,

Which the consumer later
assembles to the table.

Components include the net
posts, side panels, wheels,

Wheel brakes, and
the ball return box.

Finally,
the plate half is transferred to

An automated system,
which completes the packaging.

Many ping-pong tables
on the market

Require the net to be removed

Every time you fold the table.

The design of this table

Enables the net
to remain in place

Whether the table is
folded for storage

Or has one or both sides
open for playing.

Less setup time
means more time to play.

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Narrator:
plastic model kits were
developed before world w*r ii,

When people became interested
in seeing machines

In small-scale replication.

Today plastic model kits
continue to offer

Building opportunities
to hobbyists,

Who love the challenge

Of putting
little pieces together.

With a plastic model kit,

A colossal ocean liner can be
replicated in small scale.

Built with nearly 2,000 pieces,

Assembly is all about
the details.

Each model kit starts
with extensive research

And design,

A process that can take up to
a year to complete

And cost up to
$100,000 dollars.

Using the computer design,

A set of steel molds is made

For every piece of the kit.

Tools carve into steel chunks

To make the molds.

Precision work
done entirely by machinery.

Installed in large dies, the
molds are linked by channels.

Melted plastic will flow
through the channels

To fill the molds.

Clear polystyrene is used
for transparent components.

The melted polystyrene is
pumped under high pressure

Into the molds.

Once the plastic hardens,
a pusher ejects the parts.

The connected kit parts
are known as a tree.

The opaque polystyrene pellets
are used to form

The other kit parts
and are molded separately.

The scale of the parts
is 1 to 24,

Which means the model will be


Since the manufacturing
is automated,

The risk of contamination
is reduced.

Next, the tree is put through
a technical analysis test.

The technician photographs
the tree

And compares it to an image
already fit to scale.

If some parts
haven't taken shape

Or if they're only
partially formed,

More pressure may be needed
to ensure that the polystyrene

Flows into
all the mold cavities.

A technician compares a randomly
selected tree to the design

And verifies that no parts
are poorly formed or missing.

Once the confirmation
is attained,

The technician slides
the model kit parts

Into a clear plastic sleeve.

Before it's ready for retail,

The kit needs a set of
illustrated instructions.

The designer
deconstructs the model

And then reconstructs
it on his computer

As he draws up the instructions.

With the instruction manual
complete,

A team packs all the components
of the model kit in a box.

One of each of the kit trees
is placed in each box.

The kit also includes decals

And large,
separately molded parts,

Like the ocean liner hull.

A technician closes the box.

As it moves down a conveyor,

A laser prints the date of
production

And the batch number
on the side.

Then, the box
is wrapped in plastic,

And the ends are sealed
with heat g*ns.

A year of planning has gone into
making the plastic mold kit.

But took less than 10 minutes
to mold the kit parts

And package them.

Building the model will
take 10 to 12 hours.

The factory does a test build
on each model

To confirm that it
comes together as planned.

This is the iconic
constellation aircraft,

A world w*r ii
military transport plane

That was later converted
to a commercial airliner.

Assembling a plastic model kit

Can be a great learning
experience for the builder.

Decals mimic
the i.d. Information

On the outside
of the original aircraft.

These decals have been
pretreated with adhesive.

Soaking the decals in water
activates them.

The assembler brushes more water

Onto the design spots
on the model.

And applies the decals
to the dampened spots.

As the glue dries,
they adhere to each other.

The plastic models
can also be painted

before the decals are applied

For refined and clean look
that really comes together.

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Narrator:
the light microscope was
invented in 16th-century europe.

It allowed the human eye
to see tiny things

That couldn't be seen before.

A sophisticated research tool

With focused light
and optical lenses,

Can magnify
biological tissue,

Minerals, and computer chips.

Observation is an important
aspect of science.

The light microscope increases
the power of observation,

Making it possible to see things

That can't be seen with the
naked eye.

This 19th-century microscope
represented a turning point,

With lenses that delivered
more light to specimens,

Increasing resolution.

A light microscope often
has multiple lenses,

All made from
special optical glass.

A drill with a core bit
tunnels into the glass

To produce several
solid cylinders.

The drill cuts them larger
and thicker

Than the final specifications.

This gives technicians
extra material to work with.

A tool moves the cylinder
against a spinning blade

Slicing it into lens blanks.

The cylinder is first glued
to a glass block,

Then glued to the tool.

This method holds the cylinder
in the correct position.

Since bits of glue are left
on the lenses,

A thorough washing removes them.

Next, a device grips the lens
using vacuum pressure

And angles it for grinding.

Multiple grinding tools
remove any excess glass

And shape the radius
of the lens.

In a process known as lapping,

A technician applies
a fine abrasive compound

To a bowl
with the desired contours.

He rotates and rubs the lens
against the bowl

To further shape the lens.

He rinses off the lens
and holds it against a light

While he examines it
for scratches.

He measures the radius
of a master lens

And compares it to that of
the lens he's been working on.

If the measurements are off,

He'll remove more material.

Once additional material
is removed,

He measures
the thickness of the lens

And compares it to what it was
before the adjustments.

Next, these polishing tools
will be used

To fine-tune the profile
of the microscope lenses.

To protect the lenses
during polishing,

A technician sprays on
a temporary lacquer.

These tools will remove

Just a fraction of a millimeter
of glass,

But it will make
an important impact.

Polishing liquid
provides fine abrasion

And enables the tool
to move across the glass.

Then, a robot trims
the edges of the lens.

A device clamps
the lens in place

As trimming continues
along the edges.

Trimming allows the lens
to reach the correct diameter.

Next,
the lenses are cleaned

In multiple
water-based solutions.

In the baths, the vibrations
from high-frequency sound

Create a gentle
scrubbing action.

The intensive cleaning
leaves the lenses pristine.

A technician places
the freshly cleaned lenses

In round trays.

She handles them very carefully

Inserting them individually
into each tray slot.

Because they're
extremely fragile,

The slightest pressure
could crack them.

The lenses in the trays
will receive

An antireflective coating --

One that will prevent a loss
of light due to reflection.

Next,
the antireflective material

Is loaded into
a coating machine.

The technician adds
a specific amount

Of magnesium fluoride
into a receptacle in the base.

She inserts a piece
of aluminum oxide

In the next receptacle.

And transfers the microscope
lenses to the chamber,

Placing the rack on top.

Inside the chamber, heat
and a targeted plasma beam

Evaporate the materials.

They precipitate
onto the lenses,

Forming a coating.

Coming up, all is revealed

As the lenses come together
in the microscope.

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Narrator:
light microscopes bring
the invisible into focus.

Similar to telescopes,

A tiny specimen is placed
under the lens assembly,

From which the viewer can
discover what lies within.

By magnifying the minuscule,

The light microscope
has become an indispensable

Scientific tool.

The light microscope
often has multiple lenses.

Throughout
the production process,

The lenses are put under
the microscope

To confirm
that the geometry is correct.

A technician magnifies
the lenses one at a time,

Measuring their radius
and the diameter.

Meanwhile, computerized tools
shape the edges of glass prisms.

The prisms are triangular lenses
that bend or refract light,

Aligning colors at a focal point
for a clearer image.

Once the shaping is complete,

A technician positions a prism
on a holder to be calibrated.

She aims a laser at it.

The light passes
through the prism,

Reflected in a mirror,
and bounces back.

A computer magnifies
the surface of the prism

A thousand times bigger than its
original size,

Measuring the degree to which
the prism refracts light

And the flatness on each side.

This is an inside look at a
microscope lens assembly,

Revealing
the combination of lenses.

A prism can be an important
part of this combination.

The cast-aluminum housing
has been equipped

With the circuitry.

Some of the connections
have already been made.

It's ready
for the focusing mechanisms

That allow the user to zoom in
on tissue or other specimens.

A technician inserts
the motorized focus drive

Into the housing

So that the ends protrude
from both sides.

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He attaches adjustment knobs
to the ends.

The larger part of the knob
is for quick motorized focus.

The small one is for slower
and more precise focusing.

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He slides
a protective rubber cap

Onto the fine-focus component
of the knob.

Another technician
mounts a system

For revolving lenses
to the microscope.

This is called the nosepiece.

He wires the nosepiece
to the controls.

Using compressed air,

A technician cleans a part
known as the side port revolver.

It's equipped with a mirror,
prism lens,

And a magnifying lens.

It will reflect light
to the lenses in the eyepiece

Or external cameras.

Then the side port revolver
is tested.

At this point, multiple lenses
have been installed

In the tube lens assembly.

The technician screws the
assembly to a revolver.

Light from
the illuminated specimen

Shines through the tube lens
in parallel rays

The rays are projected
onto the eyepiece

Or external camera.

He looks through the eyepiece

To check the positioning
of the lens in the revolver slot

Making adjustments if needed.

A reflected-light illumination
system is installed.

This part directs light through
the lens and onto the specimen,

Then back through the lens

To the eyepiece
or external cameras.

This system makes it possible
to magnify opaque specimens.

Then a technician installs
the transmitted light arm.

The light arm is used
for magnifying transparent

Or thin specimens.

It does this by directing
light through them.

A technician performs
a final inspection.

He places specimens
under the microscope,

Checking the brightness
of the transmitted light

And the resolution
of the magnified image.

He tests the focus of
all the lenses in the nosepiece

To confirm that each one
delivers a sharp, clear view.

He verifies that the revolving
mechanisms move smoothly

And are in good working order.

After this final inspection,

This light microscope
is ready for research.

By imaging small things,
big discoveries are possible.

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