The story of tequila begins many centuries ago, when mexico's aztecs fermented the juice of the agave plant to produce a low-alcohol drink called pulque.

When the spanish conquistadors arrived, they added distillation to the process for a much stronger drink, and tequila was born.

Tequila is to mexico as champagne is to france.

Tequila is only made in this part of the world, and mexico has claimed exclusive rights to the word "tequila".

For centuries, workers called jimadores have grown and harvested the agave plant for tequila.

It takes seven years, on average, for a species called weber blue agave to mature.

And even today, it's harvested entirely by hand.

Using a lethally sharp hoelike tool, the jimadores chop away the greenery until all that's left is the huge core, called the piña.

Filing the round blade frequently keeps it razor-sharp, allowing them to remove most of the bitter-tasting leaves from the piña.

The tequila distilled from this crop will be a premium grade made from 100% agave juice.

The jimadores routinely remove a small piece and measure the starch content of the crop.

Only if it's deemed to be sufficient is the agave piña sent to the distillery.

Workers wield special hatchets to carve the huge piñas into quarters.

They're a more manageable size for baking.

They transfer the chopped piña to a brick oven, where it's steam-baked for 79 hours.

This thorough cooking converts the agave starch to sugar.

In the process, the flesh softens and the color turns from white to reddish brown.

The baked agave piña now spills into a shredder that rotates to tear the fruit into long, thin fibers.

The fibers exit onto a conveyor.

The shredded piña lands in a pit, where a worker forks it up and moves it into the path of a huge stone wheel called a tahona.

Operated mechanically, the tahona wheel turns to crush the fibers and squeeze out the precious agave nectar.

It takes two hours of crushing to extract all the juices.

They pipe the juicy mash into wooden tanks and add yeast.

The yeast causes fermentation, a process by which sugar is transformed into alcohol.

After 72 hours of fermentation, the alcohol content reaches 5%.

The fermented pulp and juices have an earthy, acidic bouquet, and the aroma fills the air.

They transfer the fermented mash to small copper stills.

Inside the stills, the alcohol is boiled off and the vapor condensed into a more potent liquid.

This is called distillation.

After two distillation cycles, they have tequila.

A technician measures the alcohol content, and it's 55%.

After straining out the pulp, they transfer the tequila to steel tanks.

They add purified well water to dilute the alcohol content and bring it down to 40%.

This tequila is now ready to drink, so it's over to the bottling line.

With the bottles upside down on a revolving carousel, they spray the inside with real tequila for a quick rinse.

The grippers flip them right-side up so they can be filled with 100% agave tequila.

This automated system keeps the fill level precise.

An employee corks the bottles and then sends them down the line.

The next worker presses adhesive-backed transparent labels onto them.

The see-through labels showcase the clarity of this fresh, premium tequila.

For a drink with a little more complexity, they age the tequila in oak casks for two months or more, depending on the grade.

During aging, the tequila takes on a woody flavor and turns a warm shade of amber.

The master distiller personally approves each batch.

He checks the color, inhales the aroma, and puts his observations down on paper.

He also takes a little sip.

No longer a rough swill for banditos, tequila has gone uptown and evolved into a more sophisticated drink.

Waterbeds have come a long way since the ancient persians slept on water-filled goat skins.

Hitting the market in the late 1960s, early models were pretty wavy and made some people seasick.

But innovative changes in design make today's waterbeds as stable as a traditional mattress.

Water doesn't compress, it displaces.

That's why a waterbed mattress shapes to your body, giving you equal support everywhere with no pressure points.

A washable quilted cover sits on top of the mattress to provide extra cushioning and absorb perspiration.

The mattress is made of high-durability vinyl.

It arrives at the waterbed factory in giant rolls which workers feed into a conditioning machine.

At a speed of one yard per minute, the machine heats the vinyl to 100 degrees fahrenheit.

This preshrinks the material, ensuring the mattress won't contract over time.

Next, computer-guided machines cut out the mattress's top and bottom pieces.

Die cutters stamp out the smaller and simpler corner and valve-related pieces.

Then, workers lay the top piece on a wooden pattern mold.

Applying this pattern makes the vinyl more flexible, enabling the mattress to better follow the form of the body.

The company won't reveal exactly how this caged device molds the pattern into the vinyl.

Now, with a die, workers cut a hole in the top piece for the fill valve.

After fitting the valve and cap to a piece of vinyl printed with product information, they lay on the top piece, then fuse the vinyl with a high-frequency welder.

It emits high-frequency electromagnetic waves that heat and cause the molecules to interact, blending the two pieces seamlessly into one.

Next, the corners of the mattress.

This is the most complex part of the process because it requires making a very particular angle.

After fusing the folds with the high-frequency welder, they slip each corner onto a rounded form, then close off the tip by welding on a circle of vinyl.

This makes a rounded corner, which is far more durable than a pointed one.

Whereas regular mattresses are foam-filled, waterbed mattresses contain fiber which makes the bed waveless.

Mattresses come in various degrees of stability.

The more layers of fiber inside, the less the mattress moves.

Once they've inserted the fiber, workers perform a final round of high-frequency welding to close up the mattress.

First, they position an aluminum stick under the area they have to weld.

A static laser line shows workers where to position the mattress in the automatic welder.

Once the mattress is welded all around, they remove the stick through the valve hole, then flatten the mattress, distributing the fiber evenly within it.

The final operation is quality-control check.

They put the mattress in a press and, with a vacuum hose, extract all the air.

Then, they set the mattress aside for six hours to ensure no air seeps back in, which would indicate a leak.

Elsewhere in the factory, they construct the frame in which the mattress sits.

The lower part is made of pvc plastic extruded into a stylish shape.

Workers fuse the frame parts with regular welding, melting, then pressing together the edges to bond them.

This factory doesn't mass-produce.

Every single waterbed is made to order from a range of decor choices.

The customer who ordered this one requested a frame upholstered in black faux leather.

The mattress sits on a thick melamine base.

They slide it into the frame, then secure it with screws.

The upper sides of the frame are made of upholstered foam, designed to be soft against the back of your legs when you sit on the side of the bed.

Waterbed mattresses are shipped empty.

The installer fills it with water at the customer's home, leaving enough space inside for the water to displace under pressure, so even if the valve is open, water doesn't spill out, even when someone's lying on the bed.

They may not be the fanciest of footwear, but flip-flops, also called thongs, are inexpensive and comfortable.

It's believed these flat sandals with the y-shaped strap are modeled after traditional japanese sandals that have a wooden sole and a "y" strap woven from plant fibers.

The anatomy of a flip-flop is pretty basic-- a sole and y-shaped straps called uppers.

The sole is constructed from the top and bottom.

They make the bottom out of either heat-moldable plastic or rubber.

An injection-molding machine shoots the molten material into passing molds.

Two fans positioned over the injector kick-start the cooling process.

Then, a continuous water-cooling system takes over.

3 1/2 minutes after injection, the material is solid.

They make the top soles from 3/10 inch-thick rubber sheets.

A hydraulic press forces a sole-shaped die through the sheet, like a cookie cutter slicing through dough.

The die also cuts a hole and two slits for attaching the uppers.

Some flip-flops have decorations on the top soles.

The design is applied on each pair manually using a standard screen-printing process.

The factory prepares a screen for each color of the design.

The screen is kind of like a stencil-- open mesh in the shape of the design, and the rest of the mesh is blocked.

Workers load a pair of soles in each station of a rotary-screen printing machine.

Then, they mount the screens.

They close the first screen over the pair of soles, then, with a squeegee, spread ink across the screen surface.

The ink passes through the open mesh, applying the design.

They move the soles to the next screen and do the same with the second color of ink, and so on.

Now for the uppers.

For this flip-flop style, they glue ribbon onto cotton tape.

Once they've correctly positioned the ribbon, they stitch it in place.

Then, they connect the left-side and right-side straps with masking tape...

Add a toe piece...

Then stitch everything together.

For aesthetics, they sew a cover piece over the toe piece.

Uppers give flip-flops their look through different materials, colors, thicknesses, and embellishments.

The design possibilities are endless.

Now to connect the uppers to the top sole, workers insert the toe piece into the toe hole and a strap end into each slit.

They apply glue...

Trim the ends...

Then insert a last-- a foot form in the required shoe size.

They pull the straps tightly against it.

Next, they coat the bottom of the top sole and the top of the bottom sole with glue.

Then, a quick trip through an oven activates the adhesive.

Workers then place the bottom sole on a positioning guide and stick the top sole onto it, locking the strap ends in between.

This is instant-contact glue, so they have just one chance to get the alignment right.

A 4-second bonding experience in a press, and they're "sole" mates.

However, the former bottom sole is slightly larger than the former top sole.

So, with a high speed sander, workers trim off the excess, leaving the edge even and smooth.

After a manual sanding touch-up, if necessary, and thorough quality-control inspection, the flip-flops are ready for packaging.

Workers stuff a pad of paper under the uppers to prop them up should the bag get squashed during transport.

Once considered strictly beachwear, flip-flops have stepped it up in style to become fashionable everyday footwear.

Not only used for jewelry or silverware, 80% of the world's silver is mined for industrial purposes.

Silver is the most conductive and reflective metal on the planet.

For example, it's used in electronic components and in construction as an insulation coating on glass.

The mining company produces silver bars, the composition of which is 93% to 97% pure silver.

It sells the bars to a refinery, which further purifies them for sale to industries.

The action begins down in the mine, where geologists point a niton gun at various spots in the rock face.

The device detects the levels of 40 different elements, including silver.

Silver in its natural state isn't silver-colored at all.

It's charcoal gray.

Those silver-looking deposits are actually zinc and lead.

Miners drill holes in the silver-rich areas the geologists pinpointed, then insert sticks of dynamite.

After the blast, carts hall the chunks of rock, called ore, to the surface.

Geologists then test ore piles and blend them as required to achieve a consistent amount of silver content per kilogram of ore.

The ore first goes into the primary crusher.

The machine's huge steel teeth break up the big chunks into smaller pieces.

Those pieces then drop through grates below, into the secondary crusher, which breaks them down into even smaller pieces.

Those go into vibrating cone crushers, which pulverize them into tiny pieces.

A conveyor transports the crushed ore to the ball mill.

At this point, the ore pieces are roughly 2/10 of an inch big.

As the mill's large cylinder rotates, steel balls bounce around inside, grinding the ore into powder.

A water-circulation system flushes the silver-rich powder out of the cylinder and into large tanks which keep the water moving.

To separate and dissolve the metals the powder contains, workers pour in acid.

72 hours later, the rock waste now settles at the bottom.

The solution containing dissolved silver is pumped through filter presses.

The filter plates are treated with a zinc-based chemical which attracts silver molecules.

As the solution passes through, the plates trap particles containing silver, forming a layer of black powder called silver precipitate.

This precipitate is composed of approximately 50% silver and 50% waste-- the waste being a jumble of various metals, dirt, and other impurities.

To separate the silver from the waste, they first dry the precipitate in a gas furnace for a couple of hours.

In the mining company's lab, technicians continuously test ore samples to determine the grade, determined by the quantity of silver per kilogram of ore.

They heat the samples to 2,000 degrees fahrenheit for about an hour to burn off the impurities.

What's left after the burn-off are the silver and other metals, such as lead, zinc, copper, selenium, and cadmium.

Lab technicians then treat the samples with a chemical that prevents silver from burning off and put them back in the oven.

When the samples come out, about an hour later, all the other metals have burnt off, and only silver is left.

They weigh the silver and compare it to the weight of the original sample in order to calculate the grade.

The key to running a profitable mine is to ensure that the grade is consistently within certain parameters.

Back at the mill, workers put the now dried silver precipitate into an oven, along with chemicals which prevent silver from burning off.

Approximately four hours later, the silver and waste have separated and melted.

Workers pour them into bar-shaped molds.

The silver, being heavier, settles at the bottom.

Workers skim off the waste floating on top.

In less than five minutes, the molten silver cools and hardens, enabling workers to extract what is now a silver bar.

The mining company sells the bars to a refinery for processing into industrial-grade silver.


Today on "how it's made"...

Windshields...

English saddles...

Butter...

And post clocks.

Drivers of the earliest cars had only goggles to shield them.

So, to protect people from the elements, the glass windshield was invented in 1904.

But there was a danger-- they would shatter on impact, injuring people.

Glass lamination solved the problem.

It was shatterproof--  a real scientific breakthrough.

To make a windshield, they start with a plain sheet of glass.

An automated plotter moves a cutting wheel over it, and the wheel scores the glass.

Now a robotic arm brandishes a torch.

It moves along the score line, and the thermal shock completes the cut.

This is the best way to cleanly cut through glass.

Next, a robot suctions up the cut piece of glass and transfers it to the next station, where it pushes the glass against a series of sanding belts.

This takes off the sharp edges.

It's called seaming.

Now a conveyor belt takes the glass through some soapy water to clean it up.

Then nozzles spray the glass with a mix of talcum powder and water.

This will prevent the glass from sticking to a second sheet of glass.

A robot now sets that second piece of glass on top of the freshly sprayed one.

This is a temporary arrangement.

The two sheets of glass are layered for processing but will be pulled apart later.

Next, they silk-screen black paint around the border of the glass that will eventually be the inner part of the windshield.

Then automated arms carry the glass to a station where samples are inspected visually.

After that, rollers transfer the glass to automatic squaring pucks, which position them.

And then a robot lifts the sheets of glass and carries them to four metal pins.

The pins recede, and the glass falls onto a bending iron.

The iron is shaped like a specific windshield.

The conveyor takes the bending iron with the two glass sheets into an oven called a bending lehr.

The lehr heats the glass sheets to almost 1,400 degrees fahrenheit, causing the glass to sink into the shape of the bending iron.

Then the glass goes through a slow cooling cycle to anneal, or toughen, the new shape.

Next, a robot picks up a sheet of vinyl cut in the shape of a windshield.

It takes the vinyl sheet to one of the newly shaped pieces of glass, just separated from the other piece.

Then another robot lowers the other identical piece of glass onto the vinyl.

And that's the formula for glass lamination-- two layers of glass with a piece of vinyl between them.

In the event of an accident, the windshield will fracture but not totally shatter because the vinyl will hold most of the broken glass together.

But, at this point, there's no clear view through that milky-white vinyl.

That's why the windshield is headed to a machine called a nipper.

The nipper presses the windshield between a series of rubber rollers, squeezing out air pockets in it.

As the air is removed, the view through the vinyl gets a bit clearer.

Now squaring pucks position the windshield, and a robot sticks brackets for the rearview mirror onto it.

This big blue chamber is an autoclave.

It's like a pressure cooker.

After about an hour in there, any remaining air pockets in the windshield are removed.

A rail system transports the tubful of windshields to the inspection station.

Here, each windshield undergoes a close-up inspection by a human.

He searches for scratches, chips, or any contamination between the glass and vinyl layers.

Now they place a 5-pound steel ball into a pulley system that raises it 13 feet high.

Yes, this is a crash test for a sample windshield.

The ball represents a driver's head.

The ball hits the glass but doesn't go through, which means the windshield has passed the safety test.

Now they view the windshield through polarized light, which reveals stress defects.

But only a trained eye can spot them.

Once it's decided that everything looks good, the shatterproof windshield is ready to be installed in today's automobiles.

Saddle-making goes back thousands of years.

But in modern times, saddle makers have realized that a bad-fitting saddle can irritate the horse.

An experienced rider will undoubtedly feel a difference in the animal's attitude and performance.

So now saddles are often custom-made to fit both the horse and the rider.

To make an english saddle, they attach both rigid and flexible steel strips to a frame made of polyurethane, which is called a tree.

Then they rivet a stirrup bar through the tree to the steel that's just been fastened to the underside.

With a jigsaw, a worker cuts a hole in the tree and then glues foam for cushioning.

Now he coats the back of the cantle, or seat, with glue and sticks a piece of leather onto it.

He crimps the leather around the edges of the tree.

And, using a special tool for cutting leather, called a clicker knife, he carves away the extra material.

Then he sprays glue onto the top of the tree and presses a layer of foam onto it.

Using an ordinary kitchen knife, he slices away excess foam at the sides and carves out more foam to shape the seat.

Then he shaves the edges with a rasp.

Next, he layers two more foam pieces over it and sculpts and shaves those layers.

He runs a measuring stick along the seat to make sure it's even, and then pastes a piece of black foam on top to add even more cushioning.

Now, with a half-moon blade, another worker slices a piece of leather to make a saddle flap.

She follows a trace-out of the rider's leg.

She feeds the flap piece into a skiving machine.

Its circular blade shaves the edges of the leather as a wheel pulls it through.

The thinned-out edges will be easier to sew later on.

Next, she heat-stamps the saddle logo onto the flap.

She also stamps the model, serial number, tree, and seat size onto the saddle.

Now she glues foam to a hard piece of leather to make a kneepad and sticks softer leather on the top, where the rider's knee will rest.

Then, using a piece of whale bone, she draws the leather tight around the edges so that it's smooth on top.

Whale bone is used because it doesn't scar or scratch leather.

Next, she seals the front edges and then crimps them together, the way a baker crimps the edges of a pie.

She pulls the leather tight from the back side and paints glue onto the fatter rim.

Then she brushes glue onto the flap and presses the kneepad and flap together so the glue sticks.

She hammers them to strengthen the bond, then stitches them together, along that glue line, using a big industrial sewing machine.

With a steel prod, she stuffs a wool-and-synthetic mixture into the panel which will be on the horse's back.

It's being stuffed with a certain horse in mind.

The amount of stuffing used depends on the shape of the horse the saddle is being made for.

She hammers it flat with a rubber mallet and then stitches the panel to the top of the saddle.

To sew through the leather layers, she makes a hole with an awl and then pulls the needle and thread through it, spraying water to keep the leather soft.

She hammers the seam to get rid of any gaps between the layers.

But sewing the back of the panel to the bottom of the seat is a bit trickier.

She uses a curved awl and needle to work with the contours.

It's taken about 25 hours to piece together this customized english saddle.

This is the saddletech device, and they use it to make sure the saddle measures up.

It measures it in four sections.

Now it's on to the tree machine.

It adjusts the gullet plate, the piece of rigid steel that sits above the horse's withers.

Plastic panels support the saddle while a hydraulic press bends the plate to fit the measurement.

Now it's time to saddle up and check the fit of this custom-made seat.

Butter has a rich history.

The ancient romans used it as a beauty cream and to treat burns.

Even the old testament mentions butter.

Abraham served it to angels.

Back then, people made butter by shaking milk in bags of animal skin or in hollow logs.

Today it's a product of modern technology.

Butter-making begins with a tanker-truck delivery to the dairy-- almost 8,000 gallons of raw cow's milk.

Workers test it for consistent color and odor before unloading it through vacuum-pumped hoses.

They pump the raw milk into a machine called a separator.

The separator spins, dividing the raw milk's fat from the rest of the liquid.

The fat is called buttercream, and the rest is skim milk.

The essential ingredient in butter is the buttercream.

It's thick, off-white, and approximately 38% fat.

Some of it goes to make 2% milk.

A worker adjusts a valve to re-insert some into the skim milk.

The resulting 2% milk is more watery than buttercream and is white.

The less the fat content, the thinner and runnier the milk is.

Back to the butter-making.

They put the buttercream in what's called a bulk tank, where mixers stir it to maintain the consistency.

After pasteurizing and then aging the buttercream for 24 hours, workers prepare to transfer it to another machine, called the churner.

First they clean the inside by filling it with water mixed with iodine.

This removes any germs left behind by the previous batch.

They spin the churner for about five minutes before rinsing it out.

Next, they pour in just under 400 gallons of buttercream, filling the churner about halfway.

It's important to leave some room so that air released in the churning process can escape through two vents in the churner.

The churner spins at 28 rotations per minute-- about the speed of a clothes dryer.

This causes the buttercream's fat molecules to bunch together, releasing water and air.

Every five minutes, a worker stops the churner and regulates the air vent on top.

When he feels there's no more air escaping, he closes the valve and re-starts the machine.

After 30 minutes of churning, the fat molecules in the buttercream are creamy clumps known as popcorn butter.

These clumps stay trapped in the churner, while the remaining liquid--  called buttermilk-- flows out a drain at the bottom.

A vacuum-pump system sends it through hoses to a nearby container.

This draining process takes about 10 minutes and produces about 210 gallons of buttermilk.

This dairy uses the buttermilk to make ice cream.

The popcorn butter--  all 1,500 pounds of it-- has the same consistency as a regular butter at room temperature.

A worker now flavors it with 30 pounds of salt.

This dairy also makes unsalted butter.

The worker closes the churner by sealing the glass window with a rubber ring and a metal collar.

This keeps the internal air pressure roughly equal to what's outside the churner.

Doing this ensures the churner works efficiently.

Another 30 minutes of churning, and the fat molecules thicken even more and blend with the salt.

What results is butter, which is yellow because of its natural vitamin a. next, a worker scoops about 66 pounds of butter into a milling machine.

The mill moves the butter into the final production phase, where it'll be shaped and put into packages.

This machine squeezes butter into an injector that's shaped like a block.

The injector then deposits blocks of butter into open packages.

The packaging paper has an aluminum outer coating.

This prevents light from penetrating.

Light can make the butter rancid.

Each sheet is 10 1/2 inches long and 7 1/2 inches wide.

Before the butter is inserted, a plastic former bends the paper into shape.

This mill operates four days a week, making up to 33 blocks per minute.

That's a fairly small quantity compared to some dairies, but this relatively slow pace allows greater quality control.

To monitor the mill's precision, workers check every 15th block to ensure it weighs exactly one pound.

The dairy then ships the butter to stores in refrigerated trucks.

Clocks on posts became popular fixtures in town squares during the 1800s.

Railways were spreading fast, and these public clocks helped people to get to their trains on time.

Today, post clocks are often designed to look like they're from the past.

But the technology that goes into making them is actually very up-to-date.

It all starts with what's called a transfer sheet.

A worker positions it over an aluminum disc that'll become the clock's dial.

She removes the sheet, sprays on a chemical, and repositions it.

The chemical will act as a release agent, detaching the vinyl numbers from the sheet so that they transfer and stick to the dial.

She then peels the sheet off.

This worker prepares a more elaborate model, with numerals in 23-karat gold leaf.

After coating them in glue, she applies a hair-thin sheet of gold.

Then she gently brushes the gold onto the numeral.

Using a computer-guided cutter, workers cut a 1/5-inch-thick sheet of aluminum into a clock's hand that's more than 3 feet long.

To boost the hand's rigidity, they crease it in a press.

This structurally reinforces the metal, helping retain the hand's shape over time.

A 1 1/2-ounce counterweight will balance the hand when it rotates.

Here, a welder builds the post by fusing a base and a column made of cast aluminum.

On another model, workers attach the housing for the clock head.

This clock will have four dials.

Other models have two.

In the paint shop, workers give the base, column, and head four coats of paint.

After applying some lubricant on a steel shaft, called a stud, a worker installs one of the clock's eight brass gears-- brass, because it's strong and durable.

A steel loop called a snap ring holds each gear in place.

One gear has what's called a vane to regulate the pulsing of the gears.

Next, a worker attaches the shaft and gear that'll control the minute hand.

Altogether, the gears form what's called the clock movement.

He screws on a brass panel called a backplate to hold the clock movement in place.

Then he attaches an electronic circuit board that'll later connect the clock movement to another component.

He installs a 115-volt motor to supply the clock's electric power.

Finally, he connects power wires and turns on the clock movement.

Here, he's checking to see that everything's properly linked and that the gears are moving well.

This company makes clock movements for clocks ranging in diameter from just 8 1/2 inches to more than 70 feet.

The gears in the largest clock are nearly 3 1/2 feet wide.

Here, you can see how the shaft that'll hold the minute hand revolves inside what's called the sleeve of the hour hand.

A worker attaches the clock movement to the back of the dial.

Then he ties wires through what's called glass standoffs.

These standoffs will cradle the clock's neon light.

The neon tube encircles the clock's perimeter.

It attaches through holes to a transformer hidden behind the dial.

He fastens the tube with rust-resistant copper wires.

Next come the hour and minute hands, now painted black.

He uses an allen wrench to attach them to what's called the hand hub.

This hub holds the hands on the shaft that's part of the clock movement.

The assembled dial now goes into its casing.

The casing has two parts-- an aluminum ring, called a bezel, around a glass cover known as a crystal.

He connects a wire to link the dials so that they'll move in sync.

The worker then inserts this casing into what will be a two-dial post clock.

Workers then turn on the neon clock light to test it.

Once the post clock's installed, a built-in sensor turns the light on at dusk and off at dawn.

Inside every clock is a controller that sets the time.

It's linked to a satellite through a global positioning system.

The gps tells the satellite where the clock's located to set the correct local time.

After starting up, the controller takes six minutes to adjust the hands to the exact time, which is determined by an international observatory in greenwich, england.

Certainly not your average pocket watch, this company's post clocks can stand more than 19 feet high and cost up to $35,000.


Headphones
Diving Regulators
Reflector Light Bulbs

In the early part of the 20th century, headphones were used mainly by telephone operators and radio technicians.

But in the 1930s, they were redesigned and marketed to the public, so music lovers everywhere plugged in and turned on to the concept.

Everyone is a music critic, but headphones allow people to crank up the volume without negative feedback from neighbors.

To make high-end headphones, an injection-molding machine first makes plastic back covers.

The mesh area will allow sound waves to pass through instead of reflecting back into the headphone.

Down the line, equipment stamps trademark and other information onto two more casing components-- a decorative metal disk, and a plastic housing.

The next machine winds copper wire that's as thin as human hair around a cylinder hundreds of times.

The winding is computer controlled to produce a critical component-- the headphone's voice coil.

When magnetized by an incoming signal, the voice coil vibrates a diaphragm, causing it to emit sound.

That diaphragm now takes shape as a press applies heat and pressure to a plastic membrane.

These tools mold the plastic to the desired shape.

The press molds the plastic thicker in the center and thinner around the outer zone for a wide and flat audio-frequency range.

A technician punches out the molded shape.

She applies a bead of glue to the diaphragm, then positions the copper voice coil in an assembly device.

She aligns the glued section of the diaphragm with the coil.

Ultraviolet light activates the glue to seal the coil to the diaphragm.

The plastic housings each contain a magnet.

The next technician installs the diaphragm and voice-coil assembly on that housing.

This takes skill because the coil must be positioned precisely for the best sound quality.

And this headphone speaker is now ready for an audio check.

A technician tests the audio-frequency range, distortion, and other factors.

Here, a technician joins the ends of curved wires in a plastic clip.

These wires serve a dual function.

They hold the headphones snugly over the ears and deliver audio signals from the left side of the headphones the right.

The next technician installs a connector for the headphone's audio cable and a plastic strain relief.

An adjustable band will allow the headphones to fit on heads of all shapes and sizes.

The operator presses the parts together with a hydraulic tool.

Moving down the line, a technician now joins the two halves of the speaker housing.

She forces the two parts together with a pneumatic tool...

And finishes it off with a decorative metal ring.

She inserts the speaker mechanism in the center of the housing, then places plastic brackets over it for protection.

She then secures the entire assembly to the housing.

Next, she solders two wires to each headphone speaker.

A plastic ring and cover protect it while still allowing the wires to protrude.

She attaches the end of the headband to the speakers...

Then solders the wires from the speaker to those protruding from the headband.

She presses a plastic grille into place over each speaker very carefully, to prevent scratching.

The headphones are now wired and ready for audio.

And whether it's rock or classical, the choice of music will be silent to all but one individual.

The diving regulator is a lifeline when you're underwater.

Invented in 1937, this device converts compressed air from diving tanks into a breathable form and delivers it to the diver via a mouthpiece.

And that means, once you've taken the plunge, you can breathe easy.

The two main parts of a diving regulator are called stages.

Computerized tools transform a piece of brass into the first-stage housing.

They carve a cavity and holes for attaching hoses and other components.

A blade cuts the part to size.

Then, a drill creates a space for the pressure-reduction valve.

This end also gets holes for more attachments.

Another tool sculpts the side to reduce the weight of the part.

Sliced in two, this is how the first-stage housing looks inside.

After it's been chrome-plated, they insert plugs for the holes that will later be used for attaching gauges, hoses, and other parts.

The fitting that connects the regulator to the scuba tank goes into a holding device, while the technician assembles a special valve for keeping salt water out.

He fits a piston onto the end of a spring, and then slips the assembly through a hole to confirm it's the right size.

He installs a filter on the other end of the spring.

Now he inserts the valve in the fitting.

He secures it with this rubber ring, pressing it into a groove in the fitting.

The valve appears to be firmly entrenched.

He presses it to confirm it operates correctly.

And he pumps water into a bunch of these fittings to confirm the valves inside are, indeed, watertight.

He attaches a rubber cover and a chrome-plated yoke to the fitting, then installs this assembly in the housing, using a long-handled socket wrench to get the right torque.

This yoke swivels to give the diver some flexibility in attaching it to the diving tank.

He now assembles a crucial component-- the high-pressure reduction valve.

Installed inside the first-stage housing, it converts high pressure to medium pressure.

He caps the yoke with a knob, then inserts a pressure-sensing mechanism at one end of the first-stage housing.

He covers it with a rubber membrane.

As the diver inhales, this membrane will trigger the valve to release more air.

The diving regulator's first stage is now complete.

He just needs to calibrate the pressure-reduction valve inside.

He hooks it up to compressed air and adjusts the valve so it reduces air pressure to a precise level.

He immerses it in water to test for air leaks.

There are a few bubbles from plunging it underwater, but nothing that would indicate a problem.

They now move on to the diving regulator's second stage, which will convert the medium-pressure air from the first stage to a breathable level.

The diver's breathing will trigger this diaphragm to open the air valve.

He attached a protective cover, and he's ready to install the second-stage valve.

After he inserts it in the second-stage housing, the technician makes an initial adjustment.

Then, using a special tool, he precisely calibrates the valve.

He removed the diaphragm for the last steps, so he reinstalls it.

Then, it's over to a guy with an ear for the job.

As air is pumped into the second stage, he listens for hisses that would indicate a leak.

Satisfied there are none, he hooks the regulator up to a device that simulates breathing and measures the effort required to inhale.

If it checks out, they link the two stages with a hose, and this diving regulator is now equipped to handle the pressure.

Good lighting is often a matter of reflection, and that's why, early on, lamps often came with reflectors.

But, in 1935, a company figured out how to make light bulbs with built-in reflectors.

Sealing the reflectors inside the bulb kept them clean and maintenance-free.

As track lights or in recessed fixtures, reflector bulbs can light up a room at the flick of a switch.

The creation of these bulbs begins with the bulb shell, known as the glass envelope.

It's comprised of numerous raw ingredients and recycled glass.

Production is almost entirely automated.

An operator activates equipment that weighs the ingredients and releases them into a huge hopper, where they're mixed thoroughly.

This concoction then flows into a furnace heated to 2,700 degrees fahrenheit.

It takes up to 24 hours for the mix to melt into a taffylike glass.

It flows between rollers that shape it into a ribbon.

One roller has little pockets on the surface, which form the ribbon into segments.

These devices, called blow heads, inflate the glass segments through holes in the conveyor chain.

This stretches the glass into oblong bubbles called blanks.

Iron molds encase the warm and pliable glass blanks.

The molds spin as the glass hardens into the desired shape.

The glass blanks now look like upside-down martini glasses.

This is the reflector bulb's glass envelope.

It takes just seconds for a glass blank to be transformed inside one of these molds.

The envelopes are still linked by a ribbon of glass at the top, so an automated hammer now gently knocks them free.

The glass envelopes cool down slowly.

This stage, called annealing, toughens the glass to reduce brittleness.

They measure the thickness and diameter of one of the envelopes.

If it's not up to standards, the entire production run will be crushed, and the glass recycled into new ones.

But the envelope is good, and so, production continues.

They lower the envelopes over nozzles that inject hydrofluoric acid.

It coats the inner surface of the glass with a frosty finish that will smooth the light emitted by the bulb and widen the beam.

The envelopes now head down a chute, into a padded channel that cushions their fall.

Guides gently position them.

Then, other devices thrust them into holders which move them down the line.

Next, a robot inserts aluminum wire in a heating coil and places a protective metal dome over top.

Suction cups pick up the glass envelopes and slide them onto the wire-and-dome assemblies.

A pump pulls air out of the bulb as an electrical current energizes the heating coil to melt the aluminum wire.

The aluminum adheres to the walls of the light bulb's shell, giving it a reflective finish.

The glass envelopes then move on to be stamped with the company trademark and other information.

Meanwhile, on another production line, they're preparing the glass mounts for the filament and wire contacts.

A cutting wheel slices them to size.

The tubes then travel past a flame, which melts the ends just a bit to make the edges smooth.

Once they've cooled, grippers deliver the tubes to a more intense flame, which flares them at one end.

Coming up next, we'll show you the inner workings of the reflector light bulb.

A reflector light bulb can cast one's surroundings in a whole new light-- one that's more intense and focused.

The source of this light is an electrified filament of wire.

And assembling that filament in the bulb is a very delicate task that's performed entirely by machines.

Production now focuses on the glass tube that will serve as the mount for the filament and its electrical contacts.

Machinery inserts two copper wires into each tube.

These are the lead wires that will eventually connect the base of the bulb to the filament and deliver the electric current.

These long glass tubes will be used to suck air out of the light bulb, preventing oxygen from reaching the filament and destroying it.

They protrude from the glass mount, but that's just temporary.

They will later be cut shorter.

Torches now melt the glass mount, lead wires, and exhaust tube together.

Mechanized fingers then pinch the layers together, and the wires are now encased in glass but protrude from the glass base.

Grippers transfer the closed mounts to a carousel.

It revolves to allow the mounts to receive a coil made of tungsten metal.

This coil is the filament of the reflector light bulb.

Mechanized fingers attach the small coil to hooks on the two lead wires.

The coiled filament is wobbly, so next it gets some support.

First, machinery bends the lead wires to move them and the filament out of the way.

Then, a robot presses the tip of the glass exhaust tube onto a burner.

The tip melts, allowing a metal support wire to be embedded into it.

Another robot bends the lead wires to position the filament adjacent to the support wire.

The next station loops the wire around the filament.

This gives the filament the necessary support, and it stops wobbling.

This 2-pronged device then straightens out the lead wires.

The mount is now upright and riding another carousel.

Flippers set it straight so a metal disk can be installed on the pinched section of the mount.

This disk is reflective.

It will bounce light downward to the shiny coating inside the light bulb, to create just the right effect.

With the disk wrapped around it, the assembly is now positioned on the next turntable.

Suction cups deposit the glass envelope on the assembly, to encase the filament and reflective disk inside.

The holder twirls the bulb as it travels past a row of torches.

The flames melt the neck of the glass envelope, and it closes around the glass mount.

This secures the filament, contacts, and reflective disk inside the bulb.

Another set of torches, heated to a much higher temperature, trims the base of the bulb.

Molding devices now move in to shape the bottom of the bulb so a metal base can be fitted to it.

A gripper then puts that metal base on a track to meet up with the reflector light bulb.

By now, the bulb has been flushed of oxygen and filled with argon gas so it will last longer.

The metal base finishes it off and will allow the bulb to be screwed into a light fixture.

Another flame heats the metal base to cure adhesive that was preapplied for a strong bond to the bulb.

Then, robots cut off protruding wire and form a contact on the base.

It has taken just 12 minutes to assemble this reflector light bulb, but it will provide about 2,000 hours of light.


Used for windows, doors, and partitions, patterned glass panels add beauty and light to a room.

But their purpose is more than decorative.

The designs in the glass also obscure the view, making patterned glass an effective privacy screen.

They let light in and keep prying eyes out.

With patterned glass, windows become something to look atrather than through.

There are a variety of designs and textures to choose from, offering different degrees of privacy.

At the heart of the process are engraved metal rollers that transfer designs onto glass.

Before production can even begin, this roller rotates through a chamber where grit blasts off grease and dirt.

If the designs on the roller are damaged, they shave off the outer skin, exposing a smooth surface for re-engraving.

But that isn't always necessary.

Small problems can be fixed, so they circle those for repair.

Some need no refurbishment whatsoever, so they move on to the next step.

A worker brushes a polishing compound onto the printing roller.

A buffing wheel rubs the compound into the roller's chrome surface, taking it from dull to a high shine.

Meanwhile, at another part of the factory, craftsmen repair trouble spots on other rollers.

The work has to blend in perfectly.

The craftsmen do their jobs with a finesse that comes from natural skill and years of practice.

One false move, and the entire pattern could be ruined.

But the touch-ups are perfect, and these rollers are now ready for the production line.

The raw ingredients for the glass panels are stored in huge silos.

These ingredients all come from the earth-- sand, limestone, dolomite, soda ash, and salt cake.

Here's a sampling in a jar.

Conveyor belts feed a mixed batch of ingredients to a roaring furnace.

They add waste glass and recycle it into the process to reduce the effect on the environment.

Fired at 2,900 degrees fahrenheit, the ingredients melt quickly.

Now a molten mass, it circulates in a looped pathway.

An inspector checks the melting status of the glass ingredients, as well as the flow of gas fuel to fire the furnace.

This furnace is burning 24 hours a day, 7 days a week and is monitored constantly.

The hot, liquid glass now flows between two rollers, one of them engraved.

The rollers imprint designs onto the glass and squeeze it to its final thickness.

The glass rapidly solidifies, fixing the pattern in the ribbon of glass.

It then travels through a 65-foot-long temperature-control zone.

The glass ribbon is exposed to flames to relieve stresses caused by the manufacturing process.

This is called annealing.

The glass slowly cools as it leaves the zone.

This seals in strength and durability so it can now be cut cleanly without fracturing.

This cutter scores the glass lengthwise but doesn't cut it all the way through.

The scored line maps out the desired width of the glass.

Another cutter moves to and fro to create horizontal score lines.

These score lines establish the length of the patterned glass panels.

Then a roller pops up and breaks the glass along the horizontal score lines.

The sides of the glass now collide with little wheels known as bonkers, which snap the glass along the lateral score lines.

The waste glass falls down a chute to rollers that bust it to bits.

These bits are called cullet, and they'll be recycled into new glass.

A worker now backlights glass panels and examines their finish for flaws.

This solar glass panel has a matte finish.

Compared to the small sample of standard, clear glass, it's less reflective, allowing more of the sun's energy to be captured.

Minerals high in iron produce greenish glass that's light-absorbent.

For solar glass, they go easy on the iron to produce white glass that transmits light.

A carrier with suction cups stacks the glass for shipping.

Now all that's left is the window shopping.

Road cases are designed for the job of transporting sensitive equipment, like musical instruments and audio systems.

These wheeled trunks are tough on the outside, with cushy foam on the inside.

With road cases, the gear arrives intact and ready to rock 'n' roll.

Behind every superstar, there is plenty of this custom luggage.

Each case is designed for a particular piece of equipment, like an audio-mixing console.

The case is being made to measure.

They load the dimensions of the audio console into a computer and then design a virtual case around it using three-dimensional software.

Once a customer approves the computer blueprint, they're ready to build.

Workers roll adhesive onto thick birch plywood.

They coat the entire sheet.

The plywood is now ready to receive a thermoplastic outer skin.

They align the thermoplastic with the adhesive-coated plywood and lower it into place.

They feed the thermoplastic and plywood layers to rollers that squeeze out any bubbles for an airtight bond.

Then the heat from this hot press activates the adhesive, and it cures for an even better bond to the plywood.

The result is a laminated thermoplastic plywood sheet.

Next, a computer-guided router carves through the laminated sheet, following the design drawn up in cyberspace.

This produces the exterior panels, each one precisely sized for the audio-console case.

The router also cuts out holes for latches and other fittings.

A worker pieces together the panels to form the basic carcass of the case.

He tacks them together temporarily with a staple gun.

He'll join them permanently with extruded aluminum trim.

He preps the aluminum edging by punching rivet holes in it at strategic locations.

He also cuts notches for bending it around corners.

He's now ready to install the aluminum trim.

He can actually bend the corners by hand for a perfect fit.

The edging gives the case a tailored look, and once riveted to the panels, it will hold it together.

He drills through the holes in the trim to make corresponding holes in the laminated plywood.

He inserts rivets into the holes.

These rivets have mandrels attached to them.

He drives those mandrels through the rivets, causing them to expand around the drilled holes and secure the trim to the trunk.

With the job done, the mandrel breaks off and is disposed of.

With the case now held together by the metal trim, he rivets the latch to it, and then it's on to the inner framework.

The plywood parts have also been cut with computerized precision designed to hold the audio console.

He reinforces a piece called a cheek with a thick block of wood.

This cheek is one of the two that will cradle the audio console.

He bulks up the wide end with plywood copies of the cheek's contoured profile, gluing them and nailing them to the main part so this reinforcement job holds.

He spray-paints the cheek substructure black, giving it a durable, textured finish.

He fits the cheeks in the case, one on each side, and bolts them into position.

Another worker hot-glues blocks of foam, each specifically cut to fit together like pieces of a puzzle as he installs them in the case.

All this padding will cushion the impact of any bumps on the road or backstage jostling.

He even covers the top of a plywood drawer made for a keyboard.

They slide the audio-mixing console into the case to try it for size.

From start to finish, it's taken about three hours to make this road case.

It should last for as long as the audio equipment does, but it all depends on how rough it gets on the road.

Many animated films and tv shows use stop-frame animation.

The characters are three-dimensional puppets with movable facial and body parts.

The animator moves the puppet ever so slightly for each frame of film or video.

When you view the frames at regular speed, the puppet appears to be moving.

Timmy  it's timmy  he's the little lamb...

Bringing a make-believe world to life through stop-frame animation takes a large and talented team, which includes writers, directors, animators, set and prop makers, camera crews, and, of course, puppet makers, who create, maintain, and repair the puppets.

To see how stop-frame animation works, let's rewind this scene, which stars timmy and features a red balloon.

The director takes the writer's script and breaks down each scene of the episode into a series of shots.

This shooting script then goes to the storyboard artist, who draws each shot of the scene on a digital storyboard tablet.

For each scene, the director prepares a set plan detailing the background elements, the puppet placement, and the camera angles.

The storyboard artist sends his drawings to the editor, who works with the director to edit them into an animatic, a still-drawing version of the episode.

actors, meanwhile, have recorded the dialogue in a sound studio.

Now the editor cuts that dialogue into the animatic.

The visuals in this soundtrack must be perfectly synchronized, because the animators will use the animatic as a frame-by-frame guide for moving the puppets' bodies and lips.

Baa!

Ooh!

[ squealing] baa!

Baa!

The show's animators refer to a large schedule board to see which scenes they've been assigned to animate.

A printout of the animatic shows all the episode shots at a glance.

In the art department, construction of the episode's costumes and props is well underway.

To make a few red balloons, for example, the prop makers sculpt one out of molding material and use it to produce a hard, silicone mold.

Then they pour a thick-setting resin into the mold cavity.

After the resin has hardened overnight, they open up the mold and extract the casting.

They drill a hole in the bottom...

Dab some glue inside...

Then insert a small, triangular peg, also made of quick-setting resin.

This forms the tied balloon end of the balloon.

Now a coat of gray primer.

Then, once it dries, red paint.

When the paint dries, they drill another tiny hole at the base of the balloon and insert a strand of flexible copper wire wrapped in cotton thread.

This is the balloon string.

The team of animators shoot several scenes concurrently.

Therefore, in the puppet department, model makers produce multiple puppets for each character, plus lots of extra body parts.

Certain puppet body parts, such as hands and wings, are made of silicone with a wire skeleton within.

After forming the wire to shape and applying a base coat of silicone, the puppet maker lays it in a two-part mold, then fills both cavities with silicone.

She closes the mold...

Clamps it tightly shut, and leaves the silicone to set overnight.

The flexible, wire skeleton at the core enables the animator to position a hand or wing various ways.

In stop-frame animation, the more movable the puppet and its facial features, the more lifelike the animated character appears.

The animator moves the puppet incrementally for each frame they shoot, and 25 such frames produce just one second of animation.

Timmy's torso is a polyurethane-foam core dressed in a wool coat.

It has channels for interchangeable wires that support his head and arms.

His head is made of resin, his arm silicone over a wire skeleton.

Timmy and his friends' faces can express a wide range of emotions thanks to interchangeable mouths, flexible ears and blinks, an assortment of exchangeable eyelids conveying expressions from wide-eyed to cockeyed.

These facial features attach either magnetically or with tacky wax--  a flexible, quick-release glue.

The puppet-maintenance team packs each character and its parts in a travel box, then sends it to the animator on the studio floor.

During shooting, the animator changes the facial expressions as required.

While their work does indeed require great technical skill, the animators are actors who, under the director's guidance, perform through the puppets they bring to life.

The puppet's legs must be sturdy enough to support the weight of the upper body when the puppet is standing, so the leg skeleton is made of metal rods connected with ball-and-socket joints.

The feet are metal plates hinged to allow movement.

Just like the flexible, wire skeletons, this metal skeleton also goes into a mold to be encased in silicone.

The arms attach with square-section brass tubes so they can be easily interchanged with a few turns of an allen key.

Certain puppet movements require rigging.

A rig is a device that enables animators to raise the puppet off the floor of the set to perform jumping and skipping.

The animator can incrementally lift or lower the rig to any height and lock it there.

There are many preparations before shooting begins, such as lighting, puppet positioning...

And set dressing.

Using the animatic playing on a monitor as a reference, the director and camera operator frame the shot.

Meanwhile, the set dressers prepare the next set, gathering whatever scenic objects they need from the set-dressing kit.

To create these objects, artists first sculpt the shapes out of modeling material.

They create a mold from which they produce copies in fiberglass or quick-setting resin.

Then they paint the copies.

With the set dressed and approved, the animator can begin.

With great care referring to the animatic, he positions the rigged puppet.

Then, with the push of a button, he shoots a frame, or, in animation lingo, grabs the frame.

Next, he moves the puppet incrementally and makes slight changes to body positioning...

And grabs another frame.

25 consecutive frames equal one second of animation.

The animator's art is knowing how and by how much to move the puppet to create lifelike movement.

To get special close-up facial shots that they'll later intercut with the full-body sequence, they sometimes set the puppet on a rig positioned directly in front of the camera.

Once they've shot the animation, they take what's called a plate-- a shot of the set with puppets, props, and rigs removed.

They send the plate digitally to the editing suite, where the editor uses the visuals to cover up the rig, essentially erasing it from view.

This process is called compositing-- a little bit of behind-the-scenes artistry to create a whole lot of onscreen magic.

baa!

Ooh!


Handcuffs
Caulking Compound
Propane Tanks
Forensics

Today on "how it's made"...

Handcuffs...

Caulking and joint compound...

Propane tanks...

And forensic facial reconstruction.

When a crime is committed, a slap on the wrist usually isn't enough.

It's time to handcuff them.

The need for some restraint goes back centuries, but the handcuff's design was really improved in 1862 when adjustable ratchets were added.

They allow the cuffs to snugly grip the suspect's wrist.

When they put the handcuffs on you, you know you may be in trouble.

Handcuffs start with a roll of steel.

A machine pulls it through a straightener and then through a die that punches out a handcuff frame part.

A revolving barrel cage sifts out the waste and kicks the frames into a bin.

Here, a worker stacks "u"-shaped steel parts on a fixture, which he then clamps onto a machine.

A cutter makes ratchet teeth in the parts.

Coolant keeps the tool from heating up and getting too soft to do the job.

Each set of handcuffs will have two of these ratchets.

Next, they load steel rods into a slowly revolving device.

It moves the rods through a series of cutters.

This is how they make swivels for the handcuffs.

They round the tips of the rods and then carve necks below.

This tool slices the swivel to the proper length.

And then the partially finished swivel falls into a basket.

Next, a drill works on the rounded tip, scooping out the center.

And now you have a finished swivel.

They take two chain links and two swivels.

They make a small chain-- two links with swivels on the ends.

They lock the links and the swivels together.

And now the swivel-link assembly is complete.

The swivels will provide some rotational freedom between the cuffs.

But if they don't weld the links together, the prisoner could have total freedom.

It's time to assemble the handcuffs.

They install studs in the outer framework and attach the ratchets to them.

The swivel link fits into the little grooves in the framework.

They hammer the inner frame on and then lift the top and bottom assemblies together.

A tap with a hammer holds them loosely together.

Then a press bears down to make a tight seal.

These cuffs look complete, but they aren't quite ready for a life of crime.

They need to be toughened up.

So they spend 25 minutes in a furnace, and the searing heat hardens the seal.

This is the pawl, a spring-loaded bar that will engage the teeth of the ratchet.

They lock the pawl and spring in place.

A press pushes pins into the assembly to hold everything in position.

Then they stamp serial numbers onto each set of handcuffs so that the police can keep track of them.

Now the handcuffs shake in a vibrating bin full of stones.

This polishes the rough edges.

It's time for the ultimate test.

They activate a 500-pound pull, and the handcuffs remain strong.

They also tap each set to make sure the ratchets drop freely.

Handcuffs are temporary restraints, and most can be opened with the universal key.

They pack two with each set, along with the instructions.

There's no doubt they'll have a captive market because there's always someone who needs to be locked up.

But then again, there are also those who deserve their freedom.

The need to seal windows and cracks in walls and floors has been around since antiquity.

Lucky for us, we no longer have to stuff rags or smelly fish glue into these crevices.

Today's caulking and drywall compounds form durable synthetic seals that also blend into the decor.

This company's caulking comes in two types, latex and acrylic, both good for indoor and outdoor use.

To make acrylic caulking, they blend water with chemicals that prevent mold and help the caulking withstand cold weather.

Everything blends for about one minute.

The batch then goes into another mixer containing 1,500 pounds of synthetic resin.

They add a plasticizer that keeps the caulking flexible over time.

A combination of colorants tints the caulking-- in this case, a shade of brown called sandalwood.

After 15 minutes of blending, the caulking is ready.

To test the batch, they cure a sample at 77 degrees fahrenheit for one week...

Then check its flexibility.

If the batch gets the okay, it goes into this machine, which lines up plastic caulking tubes.

Piston pumps lift four tubes at a time, and the nozzles fill each tube with 10 ounces of caulking.

The machine can fill up to 1,000 tubes per hour.

The machine then seals the bottom end of the tubes with plastic covers.

The top ends have closed nozzles with replaceable caps.

Thanks to the resins and plasticizers, this company's products last up to 30 years.

That's the tough side of caulking, but there's also a gentler, craftier side.

Start by drawing a pattern on a piece of paper.

Then lay glass on top and run caulking along the pattern.

After 48 hours, the caulking hardens into a delicate lattice.

Then fill in the spaces with clear silicone for a frosted look.

Use a small steel brush and rubber gloves to spread it and create texture.

Perfect for a door or a bathroom window.

This factory also makes joint compound.

Use this product to cover cracks, holes, and seams in drywall.

To make it, they mix 185 gallons of water with chemicals that prevent mold and a type of clay that makes the compound more spreadable.

Now for the main ingredient--  440 pounds of chalk.

It's what remains on the wall when the compound dries.

Next, they add mica, a mineral whose tiny plates slide over each other to make the compound flexible and help prevent cracking.

They test the thickness with a device that gauges how much pressure it takes to stir the compound.

Next, they take a sample from every batch and measure the ph level.

It should have a reading of 8.8, quite high because of the chalk.

This is what's called a sandability test.

Technicians first let a precise amount of compound harden on a piece of drywall.

This machine then sands it down, applying 100 strokes in 2 minutes.

Technicians then remeasure the combined weight of the compound and drywall, registering how much has been lost.

Maximum weight loss should be 4%.

If the batch passes the test, they feed it into this machine.

It pumps compound into either small-size, 6.6-pound or large-size, 15.5-pound plastic buckets.

Then using a hydraulic press, a worker seals the containers with plastic covers.

To open the bucket, you break a small plastic tab and lift off the cover.

Joint compound also has its crafty uses.

With a stencil, you can apply small amounts in intricate patterns to decorate a picture frame or a mirror.

Now, that is some fancy filler.

Compressing propane allows you to sell it by the bottle.

When you compress it, propane gas turns into a liquid, and as a liquid, it's much more compact, which means you can pack a lot of energy into a small container.

Opening the valve converts it back to gas, giving you energy that you can put to good use.

Bottling energy means you can always have fuel on hand.

To make these tanks, they start with this big coil of steel.

A press punches out 3 disks 19 inches in diameter with each swoop.

A second press clamps the disk as a cylinder-shaped die thrusts upward, transforming it into a shell.

Each shell is 1/2 of a barbecue tank.

Next, suctioning devices carry the tank shells over to a trimmer, where a blade gives it a neat edge.

Workers then insert flanges into prepunched holes in the top shells.

The top and bottom halves of the barbecue tanks now move in separate directions.

The tops head into an automated welding station where the flanges are fused to them.

The weld has to be perfect so it can take the pressure of compressed fuel without exploding.

This die simultaneously bends steel strips into rings and punches holes in them.

These rings will be used as pedestals, and the holes can be used to mount the tank to a barbecue.

Next, a machine welds the rings to the bottoms of the tank shells.

The top and bottom tank shells converge.

And a pusher device nudges the tops onto the bottoms.

They load each freshly assembled tank onto a welding lathe.

The lathe turns as an automated welding gun follows the seam precisely, melting and bonding the two pieces together.

But this processing has hardened the steel...

Not a good thing because these tanks will need to expand and contract to accommodate pressurized fuel.

So they temper the tanks in a furnace.

They do random tests of the welded seam.

They cut out a piece of the tank and grind it on both sides to expose the weld.

Then they use a jack to bend the sample right at the seam.

It doesn't split and passes the test.

In another test, they lower a tank into a water-filled drum.

They pump water into the tank, causing pressure inside the drum to rise, proving the tank will indeed expand with pressure changes.

The tanks then travel down a row of paint guns, which spray them with electrostatically charged powder paint.

The tanks journey about a half mile to an inspection station.

Here, workers check for contaminants.

Then they drop valves into the flanged openings and place the barbecue cylinder in a special machine that screws the valve on very tightly.

In one final test, they submerge air-filled tanks in water.

If the water doesn't bubble up, it means the valve isn't leaking.

And after all that, these barbecue tanks should be able to take plenty of grilling.

When the usual ways of identifying human remains fail and the investigation stalls, police sometimes need a little image building, as in facial reconstruction.

Using the skull, they re-create the face of the deceased in hopes that it will jog someone's memory.

It's a high-tech way to solve a mystery.

To reconstruct a face, the specialist uses resin to make an exact replica of the unidentified man's cranium.

He attaches it to the rest of the skull cast.

And now he has an exact copy of the man's skull.

Next he measures rubber pegs to different lengths that are equivalent to the various thicknesses of facial skin.

The short one is placed on the forehead where the skin is thin.

Then he installs actual prosthetic eyes made of plastic.

Those are suction cups protruding from them now.

They help him to align the eyes.

He shines a light into them to confirm that they're looking straight ahead.

Next he cuts out muscle shapes from rolled clay.

This piece simulates the area around the mouth.

The man's muscles have left tension marks on his skull.

Those marks combined with the knowledge of facial anatomy help him decide where to build up muscle.

He makes the face expressionless because expressions are unique and impossible to extrapolate from a skull.

Next he sculpts muscle around the prosthetic eyes.

There are no clues about the actual shape of this man's eyes, so he gives them a generic look.

The skull does divulge the length and width of the nose as well as the location of the nostrils.

Now he builds up smiling muscles followed by fat and a salivary gland.

He uses different-colored clay so he can see them more clearly.

He maps out a location for the ears but doesn't yet attach them.

He shapes muscles in the neck, working from measurements and photos from the crime scene.

Next he gives the model skin.

As he applies this layer of clay, he uses the protruding pegs as thickness guides.

And after much sculpting, the model has come to life.

But he needs one more clay ear.

The skull offers some hints about the ears' size but not their shape, so he keeps that generic.

Now he sponges the clay to give it some texture so it looks more like real skin.

The artist snaps his picture with a digital camera and then downloads the image onto a computer.

Using photo-editing software, he transfers some hair to the shot of the clay model.

He knows from evidence on the scene that the man's hair was styled in dreadlocks and that he had a beard.

He borrows brows from another photo.

He paints in the brows with a stylus, which is a kind of computer mouse.

Using the same technique, he gives the image facial hair.

This digital artistry takes a couple of days, and the skull mold and clay model take 12 days to complete...

Time well spent because once the pictures and information are posted on police sites like this one, it may finally help them put a name to this face.


Stagecoaches
Road Reflectors
Fire Baked Pottery
Custom Motorcycle Tanks

Long before trains and buses, the stagecoach transported passengers and goods.

The coach would travel an established route in stages.

But over time, the word "stage" was used to describe the coach itself.

Drawn by two or four animals, it relied quite literally on horsepower.

Like a classic movie scene come alive, seeing a stagecoach in action is a throwback to a bygone era.

Even today, building a stagecoach, horse-drawn carriage, or covered wagon borrows techniques from a time when engineering and design were done by hand.

The creation of the stagecoach begins with drawings detailing both the look of the final product and its exact dimensions.

They start with construction of the stagecoach body.

A worker puts framing rails for the back wall into place using a mortise and a tenon joint.

The final panel slides into place, and another framing rail holds the end wall together.

The end wall is added to other pieces of the stagecoach body that have already been assembled.

The end wall has ribbing for added strength.

Although the floor is partially curved, passengers will sit or stand on the part that is flat.

The coach maker inserts the door pillars into the mortise with a few taps of a hammer.

He lowers the roof beam onto the top part of the door pillars and fastens it firmly into place.

Forging of stagecoach suspension components is done by hand.

The blacksmith begins stretching the heated bar of steel into a component called a jack.

He repeatedly heats and hammers the steel bar until it reaches the desired shape.

He hammers the tapered steel bar over an anvil to shape it into a curved hook.

Once the hook becomes an eye, he hammers a pin into it.

The blacksmith wraps the heated steel around the pin to form a snug joint.

The transformation is done without the help of presses or dies.

It's the blacksmith who essentially sculpts the metal bar into a piece that has both function and form.

The blacksmith positions the finished and cooled jack onto the undercarriage and attaches it firmly into place.

The assembly has to withstand the stresses of the leather suspension used to make the stagecoach ride more comfortable for passengers.

Using a clip, the blacksmith attaches the step used to climb into the stagecoach to the jack assembly.

He attaches a clevis to the jack assembly.

With four jacks in opposing corners, the leather suspension will rest in the clevises.

Now on to the stagecoach interior.

The trimmer inspects the hide of leather.

He positions patterns carefully, choosing leather cuts that match.

Then he'll cut the leather pieces with each pattern designated for a specific part of the stagecoach.

He places the newly upholstered cushion on the seat bench and buckles the retaining straps that hold it securely in place.

In the paint booth, this particular undercarriage is given coats of yellow and black stripes.

A worker coats the running gear and wheels with sealer to weatherproof the undercarriage.

Workers gently lower the newly painted and upholstered wagon onto the undercarriage.

They connect the two using mounting bolts.

They fix the name plate to the center of the rear axle.

To help protect passengers from the elements, this particular model comes with a roof.

Workers lower the roof posts into receiver eyes and make sure they're securely attached.

Next, a worker positions a brake pad against one of the rear wagon wheels.

He then tests the brake assembly.

The face of the brake pad can be wood, steel, or rubber, depending on the vocation of the wagon.

Now for a suspension test.

The process that began with raw lumber and steel ends up about 1,200 hours later with a stagecoach that's ready to hit the dusty trail.

Road reflectors originated in britain in the 1930s.

A cat's eyes reflected in headlights on a foggy night, alerting a driver to the fact that he was about to veer off the road, provided the flash of inspiration.

The driver went on to invent a mechanical version of the cat's eyes-- reflective road studs.

Today's reflective road studs are shining examples of innovation.

These versions are computerized and solar-powered, so they're energy efficient and they'll function in a power blackout.

It takes more than 20 parts to make one road reflector.

The assembler first solders two wires to the back of a solar circuitry board, establishing a connection.

She flips the solar circuitry board around and applies double-sided tape.

She places two strips of copper on conductive pads in the corners above the tape.

She removes the backing from the double-sided tape.

Using a vacuum tool, she transfers the solar cell to the tape.

Once in place, she turns off the vacuum and smoothes the cell to the tape.

She solders the copper strips to the conductive pads, creating the circuitry.

She connects the solar panel to the board with short, little wires called jumpers.

She slides rubber protectors onto the board.

Each road reflector will have two of these solar units.

Next, she assembles the flashing l.e.d. lights.

She solders wires to the back panels to link the lights to the main computer board.

She then applies adhesive to the panel and presses the framework for the l.e.d. lens to it.

She inserts the polycarbonate lens into the framework, and it clicks in.

There are two l.e.d. lights per road reflector.

She now assembles the reflector.

She angles shiny aluminum flaps to bounce light.

She tucks the lights into the reflector, and they adhere to the double-sided tape applied to the base.

She powers up the flashing lights and checks the intensity and the effect of the reflective flaps.

Things are looking good, so now she inserts foam in a slot at the center of the aluminum casing.

She places the reflective light unit on it.

She installs a foam-wrapped rechargeable battery in a compartment on one side of the lights.

She places the main computer board and solar cells in the compartment on the other side.

And then a computer technician programs the road reflector to interface with a control system on the street pole.

The reflector is now ready to stop traffic or at least slow it down.

A crew carves a slot in the road sized precisely for the reflector.

To keep the pavement clean during installation, one of them tapes the perimeter of the hole.

He then pumps industrial-strength epoxy into it.

He inserts a cast-iron framework into the epoxy-filled hole.

He wipes up the epoxy overflow and removes the tape.

Entrenched in the pavement, this cast-iron framework will encase the road reflector, allowing it to hold up to heavy traffic.

He screws a protective crossbar over the lights and then secures the road reflector to the support structure.

They install the wireless communication system atop a pole.

This positions it to activate the road reflectors when the curbside crosswalk button has been pressed.

Modern communications technology has improved on this 1930s invention.

Today's road reflector systems are flashier than ever, designed to attract a driver's attention and keep it on the road.

In tribal communities in the american southwest, pottery takes shape much as it has for 2,000 years.

In the hands of native artisans, mud becomes a cooking pot or a storage vessel.

No pottery wheel necessary, no kiln required-- just a roaring campfire.

Times may change, but in the southwest, tribal culture is true to its roots, creating pots that look like ancient artifacts, except they're new.

Crafted from local clay, the pots are both lightweight and durable, and their appeal is truly timeless.

The potter gathers her own clay.

This is micaceous clay from volcanic deposits in new mexico.

She also mines minerals like iron oxide to paint the pottery.

In its raw form, micaceous clay sparkles in the sunlight.

Its natural glitter will make the finished pottery shimmer.

She picks out leaves and tree roots because anything organic will outgas and cause the pottery to crack.

She transfers the clay to a bucket of water.

After three or four days, it dissolves, and she filters it to remove smaller contaminants.

Once the clay thickens to a gravy-like consistency, she transfers it to a fabric-lined mold.

She leaves it to set and coagulate to a dough-like consistency.

She kneads a chunk of it to remove air bubbles.

She then shapes it into a bowl.

It will serve as the base of a traditional storage pot.

She scrapes the pot base inside and out to thin it as it dries.

The thinning process also works the clay into a harder state.

She moistens the tip of the bowl to make it malleable and flattens the edge, creating a foundation to build up the pot.

She now rolls another piece of clay into a long, thin strand and coils it around the pot.

She blends the strand into the pot base and then shapes it to extend the pot upward.

The process is called coiling.

She continues to build up the coils, blending them until they become completely enmeshed and seamless to the rest of the pot.

As she coils and blends, she turns the pot inward, creating a shoulder near the top.

She smoothes the lip and thins the extensions to ensure the thickness is consistent.

This will prevent structural weakness.

In the hands a skilled artisan, a lump of clay has become a pot, but there's more work to be done.

She narrows the opening.

She cuts the lip in six symbolic orientations, representing north, south, east, and west, the sky, and the earth.

She scallops the edge in the direction of the cuts to accentuate them.

She smoothes the pot with a wet sponge.

Before dawn, when the wind is low, she lights a fire and places the pots directly into it.

She stacks wood around the pots, and flames engulf them.

This changes the clay's molecular structure so that it can never turn back into sticky mud.

She covers the fire with a metal tub.

The flames subside, and the pots cool.

Curing clay over an open fire isn't an exact science.

Heat is uneven, and this causes fracturing.

20% of these clay pots will be damaged.

She examines them carefully and rejects anything that is not intact.

In addition to the micaceous clay pots, she also fires some red clay ones.

She paints geometric motifs onto those, using the mineral paints she's prepared herself.

Each pot is one of a kind.

Quality varies depending on the nature of the clay and smoke patterns created during firing.

She leaves the pots made of micaceous clay unpainted for traditional reasons.

She signs the vase and includes the name of her tribe.

She tucks her biographical information into it.

She's been making pottery since childhood.

From a handful of mud to a storage vessel or cooking pot, southwest native pottery continues to be a triumph of ingenuity.

As a group, motorcycle riders aren't big on convention.

So when it comes to the look of their ride, they often go their own way.

The gas tank presents the greatest opportunity when customizing the facade of the bike.

Prominent and up-front, the tank both fuels the ride and defines it.

On a car or truck, the gas tank is tucked away out of sight.

But on a motorbike, there's no place to hide it, so you may as well just show it off.

To make a custom gas tank, the metalworker starts with a sheet of sturdy cold-rolled steel.

He traces around paper patterns to transfer their outline to the steel.

There are seven pattern pieces.

The design is a tapered classic one.

He follows the lines with an electric metal shear.

With it, he can produce a rough cut quickly.

He switches to a lever-operated shear to trim the parts cleanly and precisely.

He physically bends one piece around a tube to create the tunnel.

The tunnel is the lower section of the tank that fits around the backbone portion of the bike frame.

He cuts the tunnel to size along marked lines.

He drills holes in the tunnel for the mounting tubes.

Using threaded bolts as guides now, he positions the two mounting tubes on the holes and welds them to the tunnel, creating leak-proof seams.

With rods attached as a mockup of the rest of the tank, he tests the fit to the bike.

He confirms the handlebars move freely and that there's no interference with the engine.

Next, he uses an english wheel on the two top panels.

He rolls each panel between two wheels to take the profile from flat to curved.

He tests the curvature against the mockup rods.

It needs tweaking.

He continues to shape it until the custom gas-tank part matches the mockup perfectly.

Using another machine now, he forms a stylish curl onto the edges.

This will also allow the two parts to be joined neatly at the peak.

After marking the location of the fuel cap, he punches small holes for mounting screws.

He cuts out the hole for the gas cap.

He joins the two top sections of the custom gas tank with tack welds.

A more permanent weld will come later.

He drills holes for mounting the top panel assembly to the tunnel, spacing them to correspond with the mounting tubes.

With the mockup rods removed from the tunnel, he joins the top panel assembly to it.

He then tack-welds the sides to this custom gas-tank assembly.

He hammers the tank's front cap against a form to give the outer edges a rounded profile.

He sands the part around the edges to fine-tune the contours and ensure a perfect fit.

He tack-welds the front cap to the rest of the motorcycle tank.

And with the tank structure complete, it's time to make it leak-proof.

He does a full penetration weld on every seam.

Using a pneumatic tool, he sands the seam smooth and flat.

He then sands the rest of the tank by hand to make the entire surface uniform.

He positions the tank on the bike.

After equipping the gas cap with a gasket, he screws it tightly to the custom tank.

Using mounting screws and wing nuts, he secures the tank to the bike frame.

This custom gas tank now becomes a canvas.

He paints it and applies silver borders and graphics requested by the customer.

He connects the tank to the carburetor, and this bike is ready to show off its new custom look.


Manhole Covers
Range Hoods
Artificial Logs
Snowmobiles

Today on "how it's made"...

Manhole covers....

Range hoods...

Artificial logs...

And snowmobiles.

Manhole covers are those metal lids on maintenance holes and roadways.

Workers lift them to enter and repair sewers and other underground utilities.

Foundries make the covers out of heavy-duty cast iron so they last for decades and don't budge under passing traffic.

This company makes hundreds of models of manhole covers and collars, the rims upon which the covers sit.

They come in two types of cast-iron alloy-- either ductile iron, which has magnesium to reinforce it, or gray iron, which is heavier but just as strong.

To make a cover, they first have to make a mold.

This one's got the design of the cover's top side carved into it.

Workers pour in about 650 pounds of sand mixed with glue and a hardener.

For the underset of the cover, they repeat the step in another mold.

A worker creates a channel in the sand mold through which they'll pour the molten metal.

He plugs the hole with a wooden block to preserve the cavity beneath.

He removes the block and briefly reinserts the pipe to ensure the cavity hasn't caved in.

It takes about 15 minutes for the sand mix to harden.

A machine then inverts each box and vibrates to shake out the mold.

To make one manhole cover, workers will join molds of the top and bottom sections.

Alignment lugs and glue between the sections help them align properly and form an airtight seal so molten metal won't leak out.

Next, the machine flips the bottom mold, moves the top mold into position below, then mates the pair.

The factory buys scrap metal from demolition sites and also recycles its own.

It'll melt these metals with certain minerals to enhance the mix.

Graphite to make it malleable, silicon to make it stronger, and magnesium to make this batch of ductile iron lightweight yet strong.

Here, a giant magnet picks up chunks of recycled iron and steel.

The metal is preheated to 780 degrees fahrenheit then transferred to a furnace.

There, at 2,700 degrees fahrenheit, it takes about a half hour to melt enough metal to make 35 covers.

Workers then transfer the molten metal to a cauldron and add more silicon.

This evens out the consistency so it's easier to pour.

Besides the channel for pouring in the metal, some larger molds have vent holes to evacuate burning gasses.

It takes about an hour and a half for the metal to harden.

A conveyor then drops the molds into a container and breaks them open.

Using a hook, they pick up the casting.

This one's a collar weighing about 220 pounds.

They knock off the remaining bits of sand and excess bits of metal that formed during the casting.

These scraps get recycled into a new batch of iron.

Manhole covers vary in size according to the specifications ordered.

Most are roughly the diameter of a car tire.

The average weight is about 140 pounds.

A worker now smoothes out the edges of the collar, and then the perimeter of the cover.

This way, it will sit flush on the collar.

This machine tests the strength of the cover by applying pressure.

It must withstand the weight of a car on every one-inch area.

They paint the covers and collars by dipping them in a bath of black tar.

Once dry, the pieces have a rust-resistant finish that lasts for decades.

And the buyers expect them to last, because a manhole cover and collar cost up to $1,400.

People have cooked on stovetops for centuries, but it wasn't until about 1800 that metal stoves with flues vented steam and smoke outdoors.

Today, factories make encased fans that powerfully ventilate and also light the stovetop.

A stovetop is often called a "range," hence the name "range hoods".

No matter how well you cook, steam and smoke are inevitable.

Fortunately, the range hood's fan, called the blower, clears the air in seconds.

Production begins with this computer-guided machine.

It cuts out a sheet of galvanized steel to make part of the hood's housing.

A 300-ton press then perforates the sheet and cuts out up to 50 openings for screws, wiring, and exhaust outlets.

A worker inserts another panel for the housing in a 25-ton press.

The machine bends the steel in two places.

They'll use this component to make a circular channel that evacuates smoke and steam that often contain grease particles.

To curl the panel, the worker uses another machine with three rollers.

It forms the circular channel that fits around the blower to direct air through the exhaust.

Here a spot-welding machine joins two corners of the hood's housing.

This is mainly for aesthetics.

A weld looks better than a screw or bolt.

This 80-ton press bends the hood's shell, making one of 80 folds that give the component its final shape.

Now a worker removes the plastic coating that protected the steel during the cutting.

He applies a sticker with a product i.d. code.

Then a pad printing machine marks the brand name, 1 of 12 this factory produces.

This is the first of eight stops on an assembly line.

A worker installs a transformer to power the blower's motor and two halogen lights.

This circuit board regulates several functions, including three light intensities and the blower's four-speed motor.

She attaches the board to the housing with three screws.

This panel has lights that indicate what functions are on.

Next, the worker installs the blower's 165-watt electric motor.

The motor attaches with three screws into rubber bushings that reduce noise...

Then, light sockets made of heat-resistant plastic.

The blower's housing snaps into place around the motor.

A little silicone on the housing ensures an airtight seal around the blower.

Then she installs the blower wheel.

Next, she plugs the lights in to test them.

You press this button three times to make the lights increasingly bright.

There's one button for each of the motor's speeds.

After snapping a panel on to enclose the hood assembly, a worker attaches a plastic ring to direct air through the blower.

A computer system tracks each model's assembly.

When workers complete a step, they input it into the system.

An optical scanner also senses when they remove a part from 1 of 25 cubbies, like these removable air filters made of mesh aluminum.

The tracking system's called "polka yoke," a japanese-inspired method that insures thorough assembly.

It follows each model until workers place it in a box for shipping.

The system's final task is to ensure that they put in the mail-in guarantee card and the installation manual.

If workers forget anything, the system reminds them with a loud buzzer.

Once they staple the box closed, a machine with suction cups picks it up and stacks it 10 boxes per pallet.

All this work so you can stay in the kitchen even if you can't stand the heat.

In the mood to light a cozy fire in your wood stove or fireplace?

No need to put on your coat and boots and trudge through the snow to the outdoor wood pile.

Nowadays you can buy a box of manmade logs.

A lot less hassle for you, fewer trees die, and the environmentally friendly brands pollute less and are safer for your chimney.

These artificial logs are made entirely of compressed sawdust.

Their moisture content is less than 9%, compared to 30% in real firewood.

The compression and dryness combine to make these manmade logs easier to light than real ones.

They don't throw sparks while burning, and they produce 300% more heat than real firewood.

The high temperature burns up the gasses better, so the logs emit up to 50% fewer pollutants, and they produce fewer ashes and far less creosote, a highly flammable tar that's a natural byproduct of wood burning.

Creosote buildup in a flu can cause a chimney fire.

The sawdust comes from pure, natural hardwood, mostly oak and maple.

The log company buys it from factories that make hardwood flooring.

So from the start, these logs are ecological because they're made of recycled waste.

The sawdust is clean, and the log factory doesn't add chemicals, so it's safe to cook over the fire.

The sawdust moisture content is so low because the wood it came from was already dried in huge ovens to make the flooring.

The sawdust arrives in different consistencies, so the first step is to put it through a grinder to make the particles uniform in size.

The next step is the key one--  compression.

At a rate of 5,500 pounds per hour, an air-blowing system moves the sawdust from the grinder directly into a compression machine.

The machine is a giant cylinder with a piston that moves inside.

The piston compresses the sawdust using extreme high pressure--  6,000 pounds per square inch.

The result is a 40-foot-long compressed sawdust log.

Unlike some other brands of artificial logs, this one contains no binding agents which can pollute the air.

So how does the sawdust stick together, then?

The secret is the high compression.

The intense heat it creates bonds the natural resins in the sawdust.

As the log exits the compression machine, a cutter shapes a flat edge.

This is a safety feature.

With a flat edge on the bottom, the logs are easier to stack in the recommended three-log configuration, and they don't roll out of position.

Now, a guillotine chops the 40-foot log into 40 smaller logs, each 1 foot long.

A separator pulls them apart.

The company also produces a 10-inch log.

The logs drop onto a conveyor belt that leads to the packaging area.

The factory boxes its logs with instructions and two fire starters.

The starters are made of sawdust and candle wax, more effective than using newspaper to get the fire going.

This competitor's artificial log breaks easily because it isn't as dense.

This company's log, on the other hand, is more solid because it's so tightly compressed.

That high density translates into more burning time.

Three logs will keep your fireplace alight for about three hours.

For centuries, inventors tackled this challenge with determination and frustration.

The first snow machines trudged through winters awkwardly and slowly.

But by the late 1950s, new technologies and materials emerged to make snowmobiles that could blaze through the snow with increasing ease and comfort.

Snowmobilers often face rugged terrain.

Snowmobiles need a rock-solid build to keep the rider safe and comfortable.

It all begins with an aluminum-alloy frame.

The pieces arrive partly assembled to the radiator.

The robot spins and positions the frame.

A computer-guided frame-rivet machine punches holes and inserts rivets directly into the frame with great precision.

This process bonds the parts tightly so they can't vibrate.

Next comes the rear suspension, aimed at making the ride as smooth as possible.

Inserting this plastic slide onto the runner minimizes friction between the track and the suspension.

A conveyor belt carries the suspension system through several stations.

Wheels and sprockets will turn the track that grips the snow.

The suspension kit with springs and coils goes directly into the runners.

Along with these shock absorbers, the suspension will fit snugly into the snowmobile's frame.

Workers tighten everything manually for now.

Later, a machine will tighten things even more.

Assembling the transmission system starts with this countershaft.

First, they install a high-performance brake disc made of forged steel.

The chain case fits snugly on top thanks to the ridges on this ring.

This die-cast aluminum casing will house two gears and a chain.

This bolt connects to a spring that keeps the gears and chain tight as they turn.

The chain-tightener must slide smoothly back and forth in its groove to keep the chain's tension even.

This test checks that the spring expands and compresses properly.

Now comes the oil gauge.

It's essential that oil lubricate the parts thoroughly because the motor will generate a lot of friction.

The transmission fits on top of the frame.

These coils, springs, runners, and wheels fit easily into the rubber track.

The rear suspension system connects to the track system while this white plastic sprocket connects the track to the transmission.

The speed sensor attaches directly to the sprocket.

Four high-grade steel bolts anchor the rear suspension system to the frame.

They're so strong that the suspension can withstand the vibrations that come with high speeds.

Now for the engine assembly.

Bolts attach the electric starter directly to the engine.

The fuel-injected engine generates a lot of heat-- up to 1,300 degrees fahrenheit.

This shield has layers of insulating wool that act as a heat barrier to protect the driver from scorching-hot exhaust.

The engine's made of cast aluminum so it's relatively light--  just 100 pounds-- and it propels the snowmobile up to 120 miles an hour.

Now for the front of the snowmobile.

This front suspension system requires a different assembly from the rear one.

A hoist brings it all together.

The gas tank is made of lightweight molded plastic rather than metal.

The throttle controls the speed just like a gas pedal in a car.

They install the throttle assembly, and a few more functional details.

These lightweight, aerodynamic plastic side panels give this snowmobile a sleek look.

And now, the final step.

The zero-gravity hoist lifts it all onto a skid.

Polystyrene sheets protect the snowmobile during transport to the retailer.

From start to finish, it's taken three hours to assemble this showroom-ready, snow-travelling machine.