All language subtitles for S22E11 - Custom Knee Braces; Ductless Air Conditioners; Window Film; Motorcycle Exhaust Systems (1080p AMZN WEB-DL x265 Garshasp)_track3_[eng]

Narrator: if you suffer from
Osteoarthritis of the knee,

Your doctor might prescribe
A knee brace.

Osteoarthritis
Is when the cartilage

Cushioning the knee joint
Wears out,

Causing bone to painfully
Rub on bone.

A brace relieves
Some of that pain

By realigning the leg to shift
Weight off the knee joint.

This dual-action knee brace
Rotates the foot,

Which moves the thighbone,
The femur,

Off the most painful area
Of the shinbone, the tibia.

It also creates what's called
A distraction,

Pulling the femur and tibia
Slightly apart

To further reduce stress
On the joint.

The brace is custom-made
For each patient.

An orthotist takes
The measurements

By passing a sophisticated
3-d scanner

Approximately 12 inches above
And below the knee.

The scanner translates the data
Into a 3-d computer image

With highly specialized
Medical-device software,

Then processes that image
Into anatomical blueprints

For a 3-d model.

The computer
Then reads the plans

And guides this carving machine
To create the model

From a block
Of high-density foam.

The carving process
Takes about 10 minutes.

The finished model is an exact
Replica of the patient's leg,

Which technicians now use
To construct a brace

That fits the patient perfectly.

After wrapping the model
In plastic film

To protect the surface

And marking the main anatomical
Landmarks of the knee,

They lay a thick foam band
Over the tibia

And begin marking
Where they'll install

The two articulation hinges,

Which rotate the foot and
Distract the femur and tibia.

This template is
For the lateral hinge,

The primary rotator.

It's situated
On the outside of the leg.

Next, taking an aluminum bar
And bending it on special tools,

The technicians form
The brace's tibial crossbar,

The band that crosses the shin
And holds the two hinges.

The foam band takes up the space
Of a silicone lining

That will go under
The tibial crossbar --

Critical cushioning to prevent
Pressure points

That can cause skin irritation.

Once the cross bar
Fits perfectly,

They reapply the template

And mark where rivets
Will attach the lateral hinge.

Then, using the same
Metal bending tools

They used to shape the crossbar,

They contour the hinge to follow
The shape of the leg.

They attach the lateral hinge
To the tibial crossbar

With copper rivets.

Copper is a soft metal,

So they can compact it
To produce a solid joint,

Which won't loosen up over time
With repeated use.

At the other end
Of the crossbar,

They affix the medial hinge,
Which produces the distraction.

When the knee is extended,

This hinge lengthens the brace
By approximately 3/4 of an inch,

Pulling the tibia
And femur slightly apart

To eliminate pain.

It's time to mold
The plastic shell,

The upper part of the brace
That fits onto the thigh.

First, they soften a foam sheet
In a low-temperature oven

And wrap it around the model.

This takes up the space
Of the fabric lining

That will go under the plastic.

After covering the foam
In a cotton heat barrier,

They soften a plastic sheet
In the oven,

Wrap it around the model,

Staple the ends together,

Then coat the surface in talc,

Which prevents their gloves
From sticking

When they apply pressure.

Once the plastic cools,

They trace the shell's shape
And cut it out.

Then, they wrap it
In a protective vinyl finish,

Heating the material
So that it becomes sticky

And adheres to the plastic.

They also wrap
The tibial crossbar in vinyl.

Then they apply a strip
Of velcro to the underside,

Where they'll later
Adhere padding.

They install a cover over each
Hinge to protect the mechanism.

Then they cut a fabric lining
For the upper part of the brace.

It adheres to the plastic
With velcro

So that it's removable
For washing

Or for replacement
When worn out.

The brace applies the greatest
Amount of pressure

At the tibial crossbar,

So they line the crossbar with
Silicone padding for comfort.

The pad attaches
To the velcro strip.

The brace fastens to the leg
With three adjustable straps

And works only when the knee
Is extended,

Which is when osteoarthritic
Pain hits the most.

Narrator:
The ductless air conditioner,

Invented in japan in the 1970s,

Transforms homes
Into cool spaces.

This system consists
Of an outside condenser

And refrigerant lines that run
To a fan in the wall.

In homes without ductwork,

It provides cooling
Without renovations.

No central air?

Ductless air conditioners,
Also known as mini-splits,

Are a cool option.

To manufacture the condenser,
They start with copper tubing.

It will be used
To make the coils

That cool and condense
The refrigerant.

A machine unwinds six reels
Of tubing simultaneously

And pulls them between rollers.

They iron out the kinks.

Little rotating knives cut the
Tubing to the correct length.

The cut tubes exit into a device

That bends them
Around a mandrill.

This creates hairpin bends
In the center of each tube,

And they end up looking
Like big copper bobby pins.

Next, a sheet of aluminum
Feeds into a progressive die.

A press moves up and down to
Drive the metal into the die.

With each stroke,

The aluminum is shaped
Into a part known as a fin.

They'll use a hundred
Or more fins

In one air conditioner coil.

The fins fall out of the press
Into neat stacks.

A worker slides metal rods
Into the stacks

To maintain the alignment
Of the fins

And adds a steel end plate.

She now inserts
The hairpin copper tubing

Following a precise pattern.

The fins will act as a kind
Of web for the tubes.

They're an important part
Of the coil,

Allowing heat
From the refrigerant gas

To be dissipated more quickly.

Next, a press drives mandrills
Into the tubes,

Expanding them so they'll fit
Tighter to the fins.

The coil has really taken shape.

At the next station,

They load it into a hydraulic
Bending machine.

It bends one section of the coil
Around a metal form.

This gives the coil a more
Curved profile on one side

So it will fit
In the condensing unit later.

They close the open end
Of the copper tubes

With u-bend connectors.

They brace the connectors to
The tubes for a leakproof fit.

This ductless air conditioner
Coil is now complete.

They're ready to test it
For leaks.

A technician pumps
Compressed air into the unit

To simulate refrigerant.

By using compressed air,
They're playing it safe,

Because unlike refrigerant,

It won't damage the environment
If they're actually is a leak.

Once the coil is full
Of compressed air,

He immerses the part in water.

Air bubbling out would indicate
A leak that needs fixing.

A worker keeps a close watch
On each coil

As it floats by
For signs of trouble.

They're now ready to assemble
The entire condenser.

The team screws the compressor
To the base.

They install the coil

And attach a motor and fans
To cool the refrigerant.

The next part
Is the filter dryer.

It contains chemicals
To remove moisture

And filter out contaminants.

They install the wiring
And control panel

For the compressor
And fan motor.

The team connects the pump
To the coil

To suction out air
And create a vacuum inside,

Creating a perfect environment
For the refrigerant gas.

He closes the service valves

And sends the ductless
Air-conditioning unit

Down the production line to be
Charged with refrigerant.

After that, all that's left

Is the packaging
And the installation.

On a hot day,

All the consumer needs to do
Is grab the remote control

And activate
The ductless air conditioner

For some cool air.

Narrator:
Developed in the 1960s,

Window film is a product
With transparent benefits.

Applied to the windows
Of vehicles and buildings,

This tinted film lets light in

While shutting out some
Of the sun's harmful rays.

And depending on the darkness
Of the tint,

It also provides a measure
Of privacy.

Tinted window film
Allows drivers

To see things
In a different light,

One that can be
A lot less harsh.

Not only does the tinting
Mean less squinting,

It also reduces
The amount of heat

That permeates
The vehicle's cabin.

This film will also hold glass
Together if it shatters.

Because dark tints can make it
Hard for the driver

To see the road or to be seen,

The use of window film is
Regulated in many jurisdictions.

The laws vary
Depending on the region,

So the factory makes
Different window films

For different markets
And applications.

There are numerous formulations
For the tinted coatings.

It all starts
With the acrylic adhesive

That will hold the layers
Of plastic film together.

The adhesive will also serve
As the base

For the tint
And other additives.

The technician thins
The adhesive with solvent,

Which will make it easier to
Blend in the other ingredients.

Those ingredients
Include chemicals

To absorb ultraviolet rays...

...Initiators to make
The mix cure faster...

And finally the colorant.

It's carbon-based,
And as a result,

It's highly soluble
And disperses well.

Achieving the right shade
Of colorant

Is truly an exact science,

One that started beforehand
In the lab.

A technician mixed up
Test batches

Combining one or more dyes
With the adhesive base

Until satisfied
With the results.

Once the adhesive
Has been mixed,

They add a chemical catalyst
To activate it.

They're now ready
For the plastic film.

There are various grades
And thicknesses.

The type used
Depends on the type

Of window film
Being manufactured.

The plastic film
Unwinds over rollers

Into the coating machine.

At the same time,

The tinted adhesive flows
Into a pan in the machine.

A roller soaks up the adhesive
And applies it to the plastic.

The coated film travels
Over a narrow cylinder

With fine grooves
Etched into it,

And the excess formulation
Collects in the grooves

And drips back into the tank.

This gets rid of the excess
And ensures an even application.

The film then moves
Through a long dryer,

And the heat causes
The coating to cure.

The film exits under a glare
Of blue u.V. Light.

The light activates
The initiator chemicals

In the adhesive
To further cure the coating.

Next, a second
Plastic film unwinds

And meets up
With the coated one.

They travel between rollers
That apply heat and pressure

To laminate
The two films together.

A computerized system
Checks for defects,

And a worker does a double check

As the film passes in front
Of a bright light.

After a third film,
Mounting adhesive,

And release liner have been
Applied to the product,

A technician tests a sample.

She pulls it off
A piece of glass,

And a sensor measures the amount
Of force it takes.

The test confirms the window
Film grips the glass adequately.

The production run
Gets the green light,

So next blades trim the sides
And cut it to width.

The width of the film
Can be customized to the job.

At the end of the cutting line,

A worker slides a plastic core
Onto a cylinder.

He sticks the end of the window
Film onto that core.

He activates the cylinder,
And it revolves

To wind the film up
Onto the core.

Sold in rolls,

The film will later be cut
For an exact fit

To various windows
By an installer.

Window film comes
In a range of colors

With a variety
Of characteristics.

The choice is up
To the customer.

But no matter what,

Window film is sure to change
One's view of things.

Narrator: motorcycle racers

Typically replace their bike's
Standard exhaust system

With a high-performance one,

Which emits
Exhaust gases faster,

Clearing the way
For new fuel and air

To enter the engine's
Combustion chamber,

Generating more power
And better traction,

Which produces greater speed
On the racetrack.

This high-performance,
Aftermarket exhaust system

Isn't any louder than your
Standard exhaust system,

Yet it delivers
Up to 30% more power

Due to its more
Efficient design.

Rather than steel construction,

It's made primarily of titanium,

Which is more durable
And weighs half as much.

The exhaust system
Has two main components --

The muffler,
Which dampens sound,

And the header,

Which routes exhaust gases
From the engine to the muffler.

The header's tubing is made from
A super-thin strip of titanium

That's six inches wide.

It enters a forming machine,

In which 14 stations of rollers
Apply tons of pressure

To progressively curve the edge
Of the strip upward

Until they meet at the top.

The formed tube,
Two inches in diameter,

Then enters a chamber.

Inside, a welder heats the top

Until the edges fuse together
Into a solid seam.

After the 330-yard-long tube
Exits the welding chamber,

A powerful, carbide
Guillotine blade

Chops it into several
Shorter tubes.

Then, workers mount
Each of those shorter tubes

Onto a computer-guided machine,

Which bends it
To the shape required

For several exhaust systems.

Workers then separate
Each system's tubing

With a circular saw.

Like the guillotine before,
The saw has a carbide blade.

An ordinary steel blade
Isn't hard enough

To saw through titanium.

A welder assembles the tubes
To the other header components,

Among them the collar
And flange,

Which connect the header
To the engine...

And the bulbous
Resonance chamber,

Also made of titanium.

It does a pre-muffler
Sound dampening.

Once the parts are welded
And inspected,

The header is finished.

They begin assembling
The muffler

By joining the two halves
Of its resonance chamber.

The parts must fit
With a tight seal

To prevent exhaust gases
From leaking out.

They set the resonance chamber
On a welding fixture,

Take a ring made
Of perforated titanium,

And weld it
To the chamber opening.

This ring allows
A specific amount of gases

To enter the resonance chamber
At a time.

Next, they weld
A sound-absorption tube

To the resonance chamber.

They wrap
The sound-absorption tube

In a fiberglass blanket.

The muffler's housing is made
Of a titanium sheet

Which a machine shapes
Into a cannister.

At each edge,

They peel back the film

Protecting the surface
From scratches,

Then, with an automated welder,

Join the edges
With a strong seam.

Then they remove
The protective film entirely

And electrically charge
The cannister

In a mild chemical solution
For about a minute.

This anodizing, as it's called,

Changes the color
Of the titanium

And hardens the surface,
Making it more durable.

After attaching an aluminum
Mounting bracket

To the cannister,

They insert
The sound-absorption tube,

Then secure the cannister
To the resonance chamber

With screws.

They apply
The manufacturer's sticker,

And the muffler portion of
The exhaust system is finished.

To install the exhaust system,

You bolt the header
To the motor,

Which is toward the front
Of the motorcycle,

Then mount the muffler to
The other end of the header.

The muffler bolts
To the bike chassis

Via a bracket on the cannister.

Now the bike is ready
To hit the racetrack.

[ engine revving ]

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