Narrator: the first fireplaces
were strictly functional
For heating the home,
cooking meals,
And warming water for bathing.
Over time, fireplaces appeared
in other rooms of the house
And acquired ascetic features
such as wood,
Stone, or tile work.
This ceramic fireplace
is a heritage model
Inspired by fireplaces
of the late 19th
And early 20th century.
Certain tiles
are exact replicas of originals.
At the ceramic factory
they mix water with clay,
Feldspar, and silica
in a pugmill.
Together,
these formulate a clay blend.
Once the mix
is the right consistency,
The operator presses a button,
And the mill
switches to extrusion mode.
This forces the clay blend
through a mantel shaped die
And produces a 10- to 15-inch
long extruded mantel piece.
They trim the piece
with a cutting wire
To the precise length required.
They use this extrusion method
for making longer pieces.
If they need shorter ones
They often cast them
individually in a mold.
When casting they add
significantly more water
To the clay blend to produce
a liquid clay called slip.
They pour the slip
into a plaster mold.
The porous plaster gradually
absorbs most of the water,
Leaving a layer of clay
about 6 millimeters thick
On the walls
of the mantel-shaped cavity.
After a few hours,
they pour out the excess slip
And open the mold to extract
the cast mantel piece.
Once the clay becomes
firm enough to handle
They carefully trim off
the excess
Around the opening in the mold.
Then they gently smooth down
the seam
Along the junction between
the two halves of the mold.
On the opposite side
of the pour hole,
They cut out a matching hole.
This will help the clay
dry faster
By enabling air to flow through
the inside of the piece.
To compensate for shrinkage,
The molds and extrusion dies
are designed 11% larger
Than the size
of the finished piece.
Clay shrinks as it dries.
To make the fireplace's
ceramic tiles,
They produce a rubber mold
of two adjoining tiles
And place it
inside a metal casing.
They also include a release
system to help with extraction.
They fill the casing
With an exceptionally strong
type of plaster.
It sets in about half an hour,
Taking on the shape
of the rubber mold.
This plaster casting
Is the die they'll now use
to produce the tiles.
They mount the die
on what's known as a ram press
Because it literally rams
a block of clay in the die
And compresses it
with 30 tons of pressure.
The tile die is also 11% larger
than the final size
To compensate for shrinkage
during drying and firing.
They remove excess clay
And send it back to the pugmill
to be recycled.
Then they position a board
under the die
And activate the release system,
Which extracts the clay
with a blast of compressed air.
They trim off the excess clay.
Once dry,
The tiles and mantel pieces
are ready to be glazed.
Glaze is a chemical formula
Containing finely ground silica
Combined
with different combinations
Of metallic elements
to produce specific colors.
They use a spray g*n
To apply glaze to the mantels
and a tube tip applicator
To glaze the tiles.
The tiles design has raised
borders between its components.
These are called cuenca lines.
They prevent the different
colored glazes
From flowing into each other.
The glazed mantel piece
and tiles
Now go into a gas-fired kiln
for 12 to 14 hours.
The high temperature,
Triggers chemical reactions
Which harden and strengthen
the pieces.
The clay's mineral composition
transforms
Into a completely new
configuration
Of crystals and glass.
As for the glaze, its precise
formulation of metallic elements
Produces a specific color,
And the silica melts
into a glass surface.
The ceramics
are now smooth and shiny
And ready to transform
an otherwise ordinary fireplace
Into a work of art.
Narrator: many winemakers
choose to seal their bottles
With synthetic closures instead
of natural cork from tree bark.
This prevents cork taint,
Which happens when natural cork
Gets contaminated
by the tca molecule.
Cork taint is completely
harmless to humans,
But spoils the taste
of the wine.
This engineered cork
is entirely synthetic
And therefore resistant
to tca contamination.
It's made of a food-grade
polyethylene foam core
Encased
in elasticized polymer skin.
Both materials contract
to squeeze inside the bottleneck
But then regain
their original shape
To seal the opening.
To make the foam core,
They mix talc with pellets
of low density polyethylene,
A pliable type of plastic.
Then they add pellets
of dark brown and beige colorant
To mimic the wood grain look
of natural cork.
For each customer's
order of corks,
A computerized system
automatically releases
The right amount
of each ingredient
Into an industrial blender.
The blender feeds a specially
designed dual extrusion machine.
The machine melts the foam mix
to a liquid state
Then injects carbon dioxide.
This produces bubbles,
Which create the cellular
structure of the foam.
The liquid foam enters the
machine's horizontal extruder,
While elasticized polymer enters
the machine's angled extruder.
Both extruders
Squeeze their materials
through the same shaping die,
Which outputs a continuous rod
of skin-encased foam.
The foam core
immediately expands.
The elastic skin
stretches with it.
A water bath cools the rod,
Halting this expansion
at a specific diameter.
Then, an underwater
ultrasonic gauge
Measures the thickness
of the outer skin
To make sure
it meets specifications.
The rod exits the water bath
And continues cooling
and shrinking as it drip dries.
A laser gauge then verifies
that the rod is perfectly round
And measures a specific diameter
by this point.
When any of the measuring gauges
Detects an area that doesn't
meet specifications,
That part of the rod
is flagged in the system
And is discarded at the end
of the production line.
The rod now enters
the final cooling phase.
It travels in several loops past
nozzles spraying cold water.
As the rod cools,
it shrinks to its final size,
A diameter of between
It's designed to fit snugly
Inside the standard
They had to calculate exactly
how wide to extrude the rod
So that after expansion
then shrinkage,
It would end up
at this precise diameter.
The rod now enters a cutter.
The blade is so sharp that
a safety cover is mandatory.
It's removed here
only for the camera.
The winery placing the order
specifies the cork length.
Air jets automatically blow off
any corks
Cut from areas
the measuring gauges flagged
As being problematic.
The cutter slices
about 10 standard-length corks
Per second.
All the good corks
land on the conveyor belt
And travel
to the end of the line,
Where computer sensors
count them
As they drop
into a collection bin.
Additional machines print
on the winery's name and logo,
And lubricate the surface
with silicone
So the corks will glide in
and out of the bottle with ease.
The factory's on-site lab
tests samples from every order.
Sensory specialists
sniff each cork
And compare it
to a control sample.
There must be
no discernible odor
That might affect the aroma
or flavor of the wine.
If there is, the entire order
of corks fails inspection.
While natural cork
is designed by mother nature,
A synthetic cork manufacturer
can engineer the closure
To fit more or less snugly
according to the amount of air
The particular wine needs
to develop correctly.
Narrator:
multi-tiered parking garages
Have become an urban phenomenon.
With each floor
added to the garage
The number of parking spaces
increases.
In crowded cities
where land is limited,
Garages like these
are a necessity.
They build parking garages
one concrete slab at a time.
These slabs are known
as double-t's
Because the two support beams
are in a double-t configuration.
Double-t's are often
factory made
And transported
to the construction site later.
They are designed to hold up
under very heavy loads.
They make these slabs outdoors.
Wind blows dirt onto the molds,
so they sweep it clean.
This mold is about 500 feet long
And will be used
to make several slabs.
They spray an oil-based
release agent onto it.
The release agent will allow
the slabs to be easily extracted
When complete,
preventing cracking.
They spread it more evenly
using mops.
This release agent bonds
to the metal quickly
And won't wash off easily
if it happens to rain.
They're now ready to assemble
The floor slab's elaborate
support structure.
They prop up the ends
of each slab
With galvanized steel stirrups.
They place l-shaped
bearing plates
In strategic locations
along the mold.
Then they insert wooden blocks
in the mold.
These blocks will form notches
in the cast concrete
That will be used to join
the slabs during construction.
Next, workers thread
high-strength steel cables
Called tendons throughout
the beam sections of the mold.
They pull the ends through holes
to the outside of the mold
And clamp them.
A worker tucks another wood
block between two tendons
To complete the notch part
of the mold
And hold the tendons in place.
The team threads more tendons
throughout the mold,
Weaving
a strategic support structure.
To separate each cast slab,
they insert wooden dividers
With slots
that accommodate the tendons.
They adjust the location
of each of the stirrups
So that they sit at a specific
spot near the dividers.
With the final tendons in place,
they bring in a hydraulic jack.
The worker attaches it to one
of the protruding steel tendons.
He activates the jack,
and it pulls the tendon
Until it's stretched tight
like a rubber band.
He pulls the rest of the tendons
with the jack
And checks the tension
to confirm
That it's exactly the same
for each one.
Pulled tight and later released,
The cables will hold
the concrete under compression,
Adding strength to it.
Without it, the concrete slabs
Would never be able to support
the weight of many vehicles.
The next worker ties a plastic
bracket to the stirrups
To set them at the right height.
He inserts metal mesh
into the mold
Where each slab will end.
This will help disperse
Some of the concentrated
bearing stresses.
He stabilizes the mesh,
And reinforces it
with the support structure.
The team places plastic pockets
Along the tops of the beam
sections of the mold.
These pockets will be used
to chain the slab to the truck
During transport.
They'll also act as entry points
for electrical wiring
And hold controls for parking
space counting equipment.
Coming up next,
The deck section
gets plenty of extra support,
And then it's set in concrete.
Narrator: the average car
weighs well over 2,000 pounds,
So each parking garage floor
Must hold up
many times that weight.
Double-t concrete slabs
make this possible.
Each slab
has two reinforcing beams,
And each beam
has a tense steel skeleton
That compresses the concrete,
making it stronger.
With the steel tendons
Stretched through the beam parts
of the mold,
Workers now lay metal mesh
across the deck.
This mesh is known
as welded wire fabric,
And it will reinforce
the surface of the parking slab.
They tie the welded wire
together
For full coverage
across the deck.
They use plastic clips
to prop up the wire
So that when they
pour the concrete,
It will envelop both sides.
They insert handles
That will protrude from the ends
of the completed slab
To allow it to be lifted
for transport and installation.
There are four double handles
in each parking floor slab.
They enmesh the prongs of weld
plates in the steel grid.
The plates
are strategically positioned
For the welding of the slab
to other pieces of concrete.
All the prep work
is finally done,
And they pour the concrete.
The concrete flows into the beam
sections of the mold first,
And then workers spread
the overflow across the deck.
This is a high-performance
formula
That's known in the industry
as self-consolidating concrete.
It flows evenly
into tight spaces
And compacts better without
the need for much vibrating.
This leveler vibrates
the surface of the concrete
Only slightly
as it evens it out.
They then rake the surface
of the slab
To allow another layer
of concrete to adhere to it
Later during construction.
They now insert arced metal bars
Into slots
on the sides of the mold
To form a ribbed framework
down the length of it.
This serves as a support
structure for a tent.
They unroll the tarp
from a huge spool
And drape it over the ribbing.
They secure the canvas
to the sides of the mold
With hooks.
The tent will shelter
the concrete
From the wind and rain
as it cures.
Along with an additional
plastic layer,
It will contain the hot and
humid conditions created inside.
The heat accelerates the curing
of the concrete,
And the humidity
prevents cracking.
The cure takes 16 hours,
and then they roll up the tarp.
Using a torch,
they cut the steel tendons
And place the concrete
under compression.
The cuts
also separate the slabs.
A driver now parks his crane
over one of the slabs.
Workers attach the hooks
of the crane
To the protruding handles
at the ends of the slab.
They signal the crane operator,
and he activates the lift.
Thanks to the release agent
applied earlier,
The concrete slab
easily dislodges from the mold.
It's a heavy load.
Each slab weighs 40,000 pounds.
The crane sets it down
And the team inspects the slab
for defects.
Satisfied that the slab
is free of flaws,
A worker trims
the protruding steel tendons
Flush to the concrete.
Another worker
spreads a concrete-like paste
On the exposed ends
of the severed steel
To seal it from the elements.
Then a worker glues rubber pads
to the bearing plates.
They'll act as cushions
When the slab sits
on another concrete beam.
He wraps some tape around them
while the adhesive sets.
This parking garage floor slab
is now ready to join the rest.
Side-by-side,
The slabs will form
one large parking surface
To create even more spaces.
If you have any comments
about the show,
Or if you'd like to suggest
topics for future shows,
Drop us a line at...
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