All language subtitles for S10E03 - Levels; Hot Dogs; Abrasive Grains; Sandpaper (1080p AMZN WEB-DL x265 Garshasp)_track3_[eng]1

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

Levels...

...Hot dogs...

...Abrasive grain...

...And sandpaper.

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

Captions paid for by
Discovery communications, llc

The level was invented
In the 17th century

To keep structures
Plumb and true.

Without it,
Buildings would lean,

Floors would be crooked,

And maps would have inaccurate
Elevation information.

No matter what you're making,

This critical tool
Always gives it to you straight.

It's a centuries-old concept,
But still measures up.

Center the little bubble,
And you're perfectly straight.

Production begins with a length
Of laminated birchwood.

An automated router
Carves out several holes,

Three of which
Will enclose the vials.

The other two
Will serve as handgrips.

Next, it's time
To tackle the wood's perimeter.

Grooves are cut
Along the length of the wood

For the level's brass binding.

Strips of brass are unwound
Into a forming machine.

Rollers iron out the curl
From the coiling.

Other rollers
Then crimp the brass.

This process will allow
The strip

To fit into those grooves
In the wood.

Lengths of brass binding

Are loaded into a machine
That slides them into place.

This reinforces
The edges of the wood.

Over at another station,

A machine melts and molds
The plastic for the vials.

Each one
Is slightly curved inside

So the bubble
Has a place to sit.

The vials wind their way
Through a vibratory feeder.

It takes them to a gripper

That rotates each one
So the open end faces up.

In goes a squirt
Of yellow mineral spirits,

Leaving just enough room
For a bubble to form.

A robotic arm plugs the vials
With plastic caps.

Then this sonic welder
Melts the caps onto the vials

Using high-frequency
Sound waves.

Now it's time for inspection.

A tiny camera
Photographs the bubble

And sends the picture
To a computer

That makes sure the bubbles
Are the right size.

For this production run,

The bubble should be
About half an inch wide.

If it's on the mark,

The computer
Allows the vial to move on.

A printer then hot-stamps
Centering marks onto the vial.

But this spirit vial
Isn't quite ready for business.

First it needs to bake
For 24 hours.

The heat exposes any flaws,

And the defective vials
Are rejected.

The vial is illuminated
With a bright red light

As it slowly spins
Between rollers.

A camera photographs the bubble,

And a computer scans the image
To check for shifting.

Too much shifting could
Compromise the level's accuracy.

The vials that pass the test
Then go on to a molding system.

Melted plastic is injected
Into the crevices

To make a cradle for each vial.

Next, a technician
Glues the cradled vials

In the openings
In the wooden framework.

This is precision work.

Each vial has to sit
Perfectly level,

So technicians rely
On a magnified image

To check their progress.

Some vials are installed
Vertically

To gauge if the walls are plumb,

While the horizontal ones let
You know if the floor is level.

Acrylic-rimmed windows
Are fitted over the vials

To protect them.

Rubber caps are screwed
On to both ends of the level.

And finally,
The trademark stamp goes on.

These levels are now ready
To straighten up any jobsite.

When we return, the real skinny
On an all-american favorite.

Narrator: hot dogs are
An all-american fare.

But most likely
It was german sausage makers

Who first came up with the idea.

In fact, there are reports
Of german immigrants

Selling them from pushcarts
In new york's bowery

As far back as the 1860s.

A century and a half later,

Hot dogs are still the
Number-one treat on the street.

Traditional hot dogs

Are made from a mix
Of pork, beef, and chicken.

The cuts they start with
Are called trimmings --

Pieces of meat left over from
Cutting steaks or pork chops.

The trimmings are ground

The same way butchers
Chop up hamburger meat --

By pushing the cuts
Through grated metal plates.

Processed chicken trimmings
Are added to the ground meat,

Followed by food starch, salt,
And other flavorings.

These flavorings vary

Depending on where
The hot dogs are to be sold

Because people in different
Regions have different tastes.

Water is sprayed into the mix,

And everything is blended
Together in a big vat.

Corn syrup
Adds a dash of sweetness.

The addition of even more water

Helps to disperse
The ingredients

And make the hot dogs juicier.

Another machine
Then purees the meat batter

Into a fine emulsion
And vacuums out any air.

Long rolls of cellulose tubing

Are loaded
Into the stuffing machine.

It pumps the meat puree
Into these casings,

Twisting it
Every 5 1/4 inches --

The length of one hot dog.

It takes just 35 seconds

To make a chain of hot dogs that
Would span a soccer field twice.

Then three
Of those hot-dog chains

Are linked together
To make an even longer string,

And they're loaded several
At a time into another machine,

Which drapes the hot dogs
Onto moving racks.

The process is carefully timed

So that a twist
Always lands on the bar.

The racks shunt the hot dogs
Through a liquid smoke shower,

Then into an oven
With several cooking zones.

The liquid smoke
Seeps through the casing

And adds flavor to the dogs
As they bake.

Hot out of the oven,

These franks are drenched
In cold, salty water

To chill them in preparation
For packaging.

The hot dogs then file down
To an unloading zone.

Here, a machine pulls them
Off the bars onto a conveyor.

Then the hot dogs slide off the
Conveyor into metal containers.

If you've been wondering

About those black stripes
On the casings,

All is about to be revealed.

The stripe is a marker
Attached to the casing.

The absence of a black stripe

Means the hot dog is cooked
And ready for packaging.

Inside the peeler machine,

A tiny knife slits
Each casing along the top.

Then steamy air blows
The casings right off the dogs.

This machine peels
700 hot dogs a minute.

An inspector makes sure

The casing
Has been completely removed

And that there are no defects
In the dogs.

Then it's into a device

That looks like
A plastic bicycle chain.

The sprockets position
The hot dogs for packaging.

This factory manufactures

An incredible 300,000 hot dogs
An hour.

That's close
To 2 1/2 million per shift.

They really do
Churn them out like sausages.

Fire up the grill,

And a mouthwatering meal
Is just minutes away.

Up next, the hot scoop
On abrasive grains.

Narrator: it takes true grit
To make sandpaper,

As in abrasive grains.

People have been using
Abrasive minerals

To sand and polish things
For centuries.

Today, these minerals
Undergo heavy processing

To make the grade,

From very superfine
To very coarse.

Whether you're working
On metal or wood,

The right grade of abrasive grit

Is essential
For finishing the job.

The factory starts with bauxite,

A naturally occurring mineral
That resembles clay.

They add alumina,

A white powdery material that's
Actually derived from bauxite.

The bauxite and alumina are
Blended with other minerals,

Then released
Into an electric arc furnace.

Here, three large electrodes
Use intense electrical current

To heat the mix to
Over 3,600 degrees fahrenheit.

That's hotter
Than an active volcano.

In fact, the mixture
Looks a lot like lava

As the minerals melt
And blend together.

Standing well back
And using a long ladle,

A technician takes a sample
For chemical analysis.

If the mix is right,

The molten minerals are emptied
Into a big steel pot.

The searing liquid
Weighs several tons,

So a crane is needed to
Transport it to a cooling area.

24 hours later,
With the material hardened,

It's time to bring in
The wrecking ball.

It cracks open
The hardened concoction,

Which is still quite hot
At the core.

The wrecking ball
Is dropped repeatedly

To break up
The hardened minerals.

Next, the lumps
Of abrasive material

Are transferred
To a conveyor system.

Metal-plated crushers break them
Up into fist-sized chunks.

A magnet picks up
Any excess iron.

And then
It's into the roll crusher,

Where iron cylinders
Grind the chunks to bits.

Workers assemble screens
In decreasing mesh sizes

To make a kind of shaking sieve.

It sifts the mineral particles

Through the screen
With largest mesh first,

Then continues to sort the grits
In progressively smaller sizes.

For some perspective,

We placed a quarter
Against the various mesh sizes.

As you can see,

Only the finest particles could
Pass through tightest weave.

The bits of grit
Bounce across the screens

And fall into hoppers --
A different one for each size.

The coarsest grains will be used
For rough-sanding jobs.

The smaller the grain,
The finer the finish.

The finest grits
Are virtually microscopic.

The next step is to inspect
The grain's shape.

A sample is funneled into a cup.

Then it's weighed.

A higher weight means the bits
Are densely stacked

And therefore blockish in shape
With blunt edges.

A lower weight
Means they're flat and sharp.

A different test is used
For the most minuscule grits.

The particles are suspended
In an an electrolyte solution.

Then an electrical charge
Is applied.

This allows inspectors
To count and evaluate the grits

Via computer.

Now these abrasive grits
Are ready to be packaged

And shipped out.

Coming up, we'll go
To the sandpaper factory,

Where the abrasive grits meet
Their ultimate destiny.

We'll have the nitty-gritty
On that process next.

Narrator: to make sandpaper,
You need a lot of grit.

There are thousands
Of tiny abrasive grains

On a single sheet.

The whole idea
Is to create friction.

By rubbing the sandpaper
Against wood or metal,

You can remove defects
And create a uniform surface.

It's ironic that something
So abrasive

Can make things look so smooth
And polished.

Sandpaper often isn't made
From paper at all,

But fabric like poly cotton.

The cloth is unwound into
A machine with a printing press.

Rollers lined
With rubber printers

Stamp product information
Onto the cloth.

The cloth then travels
Underneath the printing press,

Where more rollers apply
A heat-setting adhesive

To the unprinted side.

A computerized system measures
The density of the coating

To ensure that it's been applied
Correctly.

Then the cloth
Is pulled one floor down

To the electrostatic pit.

Here, the environment is kept
Hot and humid --

Perfect for applying
Abrasive grains

To the cloth
Electrostatically.

The grains are poured
Onto a conveyor belt in the pit.

The conveyor moves the grains
Under the rolling cloth

And between electrodes
And ground plates.

The system generates
An electrical field

That triggers a mini sandstorm.

Once airborne,

The abrasive grains stick
To the adhesive-coated cloth

And become embedded in it.

This method allows for even
Distribution of the grains

Across the cloth.

The grain-coated cloth
Now rolls out of the pit

And back up to the main level
Of the factory.

A technician cuts a swatch
Of the sandpaper,

Then peels away layers and makes
Three different cutouts --

One of the cloth alone,

Another of the cloth
With the adhesive coating,

And a third, the grain-
And adhesive-coated cloth.

He weighs each cutout

To confirm that the sandpaper
Has been formulated

Precisely to specification.

He also examines the gritty
Surface under a microscope

To make sure the grains
Are standing up evenly.

This production run
Gets the go-ahead,

So workers move the sandpaper

Through
A hundred-yard-long oven.

It has three
Different heating zones,

Each progressively hotter.

The increasing heat bakes
The grains into the adhesive.

The sandpaper
Is now rough enough,

But it's not quite ready
For use.

In the next step,

A coat of resin is rolled
Over the gritty surface,

Binding the grains to the base.

After the resin
Is cured to the surface,

These jumbo rolls of sandpaper
Are stored in a warehouse

Until it's time
To cut them down to size.

Some rolls are sliced
Into big sheets.

These will be made
Into commercial sanding belts --

The kind used
In heavy manufacturing.

Another machine
Punches out sanding discs.

And at this station,
Four rolls of sandpaper

Are simultaneously unwound
Into a machine.

It carves the four layers
Into rectangles.

These rectangles
Won't be used for sanding,

But as grip tape
For skateboards.

From refinishing your furniture

To nose-grinding
At the skate park,

Sandpaper
Will always give you an edge.

And with so many grits
To choose from,

There really is a sandpaper
For every job.

If you have any comments
About the show,

Or if you'd like to suggest
Topics for future shows,

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