25x07 - Episode 7

[bunniefuu]

Narrator:
you can buy mass-produced skis
from a large company,

Or you could choose
to purchase a handcrafted set

From a small independent.

It's a matter of preference --

Much like drinking beer
produced by a major brewery

Versus a microbrewery.

In fact, many ski-buying guides

Call small, independent brands
microbrews.

Handmade skis typically feature

Exclusive designs
with high-end craftsmanship.

They're produced
in limited quantities

By small, independent companies.

This maker
builds the core of the ski

From two types of wood --

Colorado aspen
and colorado pine.

They're harvested from trees
k*lled by pine beetles.

Workers glue together


Depending on
the width of the ski.

The pieces form
a laminated block

That's structurally stronger
than a solid piece of wood.

They clamp the block in a press
for two hours

While the glue dries.

After they remove the block
from the press,

They use a band saw
to cut off strips.

Each strip will be
the core of a ski.

One block typically
makes six ski cores.

Next, they shape the ski cores
with a router,

Using a template
underneath the ski contour.

They apply a blowtorch

To strips of ultra-high
molecular-weight plastic

To make it bondable.

Then they coat the plastic
with epoxy

And adhere a strip of it
to each side of the ski core.

This forms a sturdy sidewall

To protect the core
from side impact.

After the epoxy sets,

They saw 6 inches off
the front and back of the ski.

With a hand planer, they taper
the thickness of the ends.

Then they heat the sidewalls
again to prep them for bonding.

But first, workers glue a
plastic core called a tipspacer

To the front of the wood core.

This holds the parts together
during construction.

Then they use
a hand-crank die machine

To die-cut
the brand name and logo

Into a strip of ultra-high
molecular-weight plastic.

They die-cut the same letters
in white,

Then place them
in the black cutout strip.

This is the ski's base.

Now they can begin
constructing the skis.

They take a left and right base

And spread epoxy
over the entire surface.

They lay down a layer
of epoxy-saturated fiberglass

And position the ski core
on top.

Then they spread epoxy
on the core and tipspacers,

As well as lay extra fiberglass

Where the bindings
will be installed.

They position steel plates
for mounting the bindings,

Then cover the entire ski with
another layer of fiberglass.

Finally,
they add a nylon top sheet

Printed with a graphic design.

They cover the assembly

With a series of metal sheets
and silicone heating blankets,

Then place everything
in a custom-design ski press.

When workers activate the press,
rubber air bladders inflate,

Pressing the wood
into a ski shape.


The skis come out of the press.

A worker separates them
with a band saw.

Using a jigsaw,
they trim the tip and tail.

The saw leaves a rough edge,

So workers
sand the entire perimeter.

Then they taper
and bevel the sidewall.

This gives the skis
a better edge grip on snow.

The final step
is to peel off the film

That has been protecting
the nylon top

Throughout construction.

These handmade skis

Come in several different
styles, shapes, and sizes.

All they need now are bindings.

Then it's all downhill
from here.

Narrator:
septic tanks are the perfect
sewage-treatment solution

For houses that aren't
connected to a sewage network.

The tank collects and treats
domestic wastewater

Using a bacterial process
to decompose waste.

It filters the dirty water

Before recycling it
back into the ground.

Septic tanks
are usually made of concrete

And have access covers on top.

The waste-treatment process

Takes place in separate chambers
inside the tank.

Steel bars called rebars

Reinforce the concrete structure
of the tank.

A welder assembles the rods
to form a cage.

Then he spot-welds the rebar
with a mig welding torch.

The welded cage will maintain
the structural integrity

Of the concrete septic tank.

The welder
measures the cage's diagonals

To make sure it's straight.

Next, the worker
places rebar spacers

To keep the cage centered
in the mold

And leveled on the floor.

A crane lowers the cage
into a custom formwork

Made of
high-strength steel plates.

Workers close the walls
around the form

And secure them in place
with heavy-duty locks.

The crane lowers
machined steel cores

To form the interior walls
of the tank chambers.

A rigid plastic tube is inserted
inside a rubber sleeve

To create a flow hole
between chambers.

Using an acetylene torch,

A worker cuts holes in the rebar
for access openings.

The mold allows concrete
to flow over the rebar

And embed the access-opening
covers in the septic-tank lid.

Workers pour over 1,300 gallons
of wet concrete into the mold.

They use a stick vibrator
to eliminate air pockets

And level the walls
with a putty knife.

Next, they mix more concrete

And pour it over
the top-slab rebar.

Concrete blocks are used

To keep the plastic covers from
floating in the wet concrete.

While one worker
pours the concrete in the mold,

The other consolidates the
mixture with a vibrating stick.

Then a worker levels the top
of the slab with a trowel.

Once the concrete tank is cured,
workers strip the forms.

They remove the concrete tank

Using an overhead crane
and a compressed-air system,

Which forces the mold
away from the concrete tank.

The crane takes the stripped
core away for cleanup.

A worker brushes
the top of the walls

And sweeps the floor
inside the tank.

Then he applies
a butyl-rubber tape

Around the top
of the exterior wall.

This forms a watertight seal
between the tank and the lid.

An overhead crane lifts
the lid out of the formwork

And brings it to the tank mold.

The crane slowly
lowers the lid onto the tank.

Workers keep it aligned
to make sure it seals properly.

Then they label the tank
to indicate its capacity.

Next, the mold is opened,

Revealing
a finished septic tank.

The rubber sleeve
molded into the wall

Ensures a watertight connection

Between the pipe carrying waste
from the home and the tank.

This tank is now ready
for delivery.

They set the tank in the ground
at the client's home

Using a radio-remote-controlled
knuckle-boom crane.

A septic tank like this will
provide a three-bedroom house

With a fully independent
sewage system.

Narrator: building a vehicle
begins with the chassis.

Chassis used to be
made out of welded-steel parts

That were very heavy
and lowered fuel efficiency.

But thanks to a manufacturing
process called hydroforming,

Steel chassis parts are
now much lighter and stronger.

Years ago,
this suspension-system component

Would have been made
by stamping a number of parts

Out of heavy steel,
then welding them together.

But today, the same component

Is made out of a single steel
tube at a hydroforming plant.

A solid tube is stronger
than welded parts,

Allowing the component
to be made out of lighter steel.

The first step
is to insert the steel tube

In a computer-guided machine
called a rotary draw bender.

The machine inserts a mandrel

To prevent the tube walls
from collapsing.

Then it bends the tube into
a starting shape for the part.

This operation
may look effortless,

But the machine's hydraulics
must generate

Nearly 9 tons of pressure
to bend the steel.

After several bends,
the part has its starting shape.

The hydroforming process begins

When a robot
places the tube in a press

For preliminary shaping.

This is called preforming.

The press forces the tube
against a die

To prepare it
for the hydroforming mold.

Here's the tube
before preforming...

And after.

Next, a robot places
the steel tube in a part mold

That's already mounted
on the hydroforming press.

The machine
fills the tube with water

And seals the ends
to trap the liquid inside.

Then the machine closes the mold

And raises the water pressure
to 20,000 p.s.i. --

More than 600 times
the air pressure in a car tire.

The high pressure
softens the steel tube,

Allowing it to conform
to the shape of the mold cavity.

When the press opens,
a robot removes

The now-fully-formed part
from the mold.

The hydroforming press
even punched holes in it

For screws and bolts.

Next, a robot transfers the part
to a circular saw,

Which cuts the component
in half.

This creates mirror-image
right and left suspension parts.

The saw left sharp edges
on the ends of the part,

So a worker smoothes them out
with a handheld grinder.

Then they inspect the parts
by putting them

In a specially designed
dimension-verification fixture.

They use tools
called precise-diameter spheres

To make sure
the clearances between each part

Meet specifications.

If the parts pass inspection,

They're shipped
to the assembly plant.

There, workers position
these parts

And adjacent suspension parts
in an assembly jig.

An automated machine
welds them together.

Then a worker
positions the next part

And welds it
to the rear-suspension unit.

He repeats this process until
the entire assembly is complete.

To make the suspension unit
corrosion-resistant,

They apply a chemical coating

Which is bonded to the steel
with an electrical charge.

Once the coating dries,

Automated machines
insert bushings

For parts that will be installed
on the suspension later.

Bushings are
rubber or polyurethane pieces

That go in between
two metal components

To absorb shock
and reduce noise.

Workers put
the finished rear suspension

Into a shipping cradle
for delivery to the auto plant.

At the plant,
assembly-line workers

Install springs
and shock absorbers.

They also mount struts,
wheels, and brakes.

Then they install
the entire unit on the vehicle.

Hydroforming allows
auto manufacturers

The ability
to produce chassis parts

In shapes impossible to achieve

By the older method
of stamping steel

And reduces
the weight of the car.

Narrator:
acrylic aquarium windows
are designed to be transparent.

But they also need to be
virtually indestructible

And able to hold back several
hundred gallons of water.

Some of the largest ones are
built to withstand repeated hits

From sharks or other big fish

That are swimming around
inside the tank.

Acrylic aquarium windows

Can be molded into
different shapes and sizes.

They can also be made
to various thicknesses.

Round, flat,
or just slightly curved,

These windows
are worth looking into,

Because they offer close-up
views of aquatic ecosystems.

Each acrylic window starts
with an engineer's design.

He takes into account
the anticipated water volume

And the type of marine life
to be housed in the tank.

Next, a technician measures
specific amounts of chemicals

To be added to the acrylic.

Two are strengthening agents

And another
is a u.v.-Light stabilizer

To counteract the damaging
effects of the sun's rays.

After the chemicals have been
mixed with the binding agent,

They add them
to a small amount of acrylic.

This premix will be added

To a much larger amount
of acrylic later.

They blend in some dye

To offset the yellowish tone
that's common in acrylic.

The result
is a h*m* mixture

With a syrupy consistency.

Using a crane,

They bring two halves
of a steel mold together

And place them on supports.

Once the walls of the mold
are in place,

They lock them together
with bolts.

The final acrylic mixture
is ready.

It now flows
into the mold cavity.

A thermostat for heat coils
located in the walls

Is activated.

They roll the mold
into an autoclave.

The acrylic
slowly bakes under pressure

To ensure a consistent cure.

It takes five days

For the acrylic
to turn into a solid slab.

An employee monitors
the temperature readings daily.

Once the acrylic cures,

They slice a piece off
and bend it

With a hydraulic tool
until it breaks.

If the piece can withstand


Without breaking,

It passes the test.

At another station, they test
the elasticity of the acrylic.

They do
a few more compression tests

To prove that the acrylic holds
strong under heavy pressure.

After testing, they're ready
to cut the acrylic slab.

Acrylic shrinks unevenly
during the curing process,

So they need to cut it

To the desired size and shape
afterwards.

As you can see, aquarium windows

Are a lot thicker
than normal windows.

To make
a contoured aquarium window,

They lower a flat acrylic slab
onto a curved molding bed.

Then they heat it in an oven
for up to a month.

This causes the acrylic
to soften

And conform to the rounded shape
of the molding bed.

Once again,
they've made the slab oversized

To account for the distortion
and shrinkage

That can occur
during the curing process.

A worker cuts the curved slab to
the engineer's specifications.

He cuts off big chunks.

They're so heavy that it takes
three people to carry them away.

They test the optical clarity
of each window.

To do this, a worker
on one side of the window

Moves a grid pattern around

While a worker on the other side

Scrutinizes the grid lines
for distortion.

Satisfied that the aquarium
window offers a clear view,

They clean and polish it
thoroughly.

They'll do a final clean after
the window is installed on-site.

The time it takes to manufacture
an aquarium window

Depends on
the complexity of its design

And the window's thickness.

Some can be produced
in as little as four weeks.

No matter how long it takes,

There's no doubt that the views
will be well worth the wait.

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about the show,

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topics for future shows,

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