Corn Tortillas
Crankshafts & Camshafts
Bush Planes
Aluminum Bike Wheels

The corn tortilla is the original flatbread invented, legend has it, thousands of years ago by a mayan peasant to feed his king.

A royal appetite may have been the inspiration for this unleavened creation, but it soon gained mass appeal and became a staple of the mexican diet.

The corn tortilla has been popular for thousands of years.

In the last century, demand has grown as people in many countries acquire a taste for tex-mex cuisine, like tacos, enchiladas, and nachos.

Corn tortillas are now mass-produced in factories, and the process starts with grade-"a" corn-- dehusked and removed from the cob.

There are millions of kernels in one truckload.

They unload onto an elevator that takes them several stories up to deposit them in a silo.

They're stored here until the factory is ready to start production.

They then spill out of the silo and into big steel cooking vats.

A worker adds water, completely immersing the corn.

He activates a steam-injection heating system, and as the temperature rises, he tosses in numerous scoops of powdered limestone.

It acts as a preservative and helps soften the kernels during cooking.

As they soften, the outer skin, or pericarp, loosens, releasing starch and creating a foamy effect.

After 45 minutes, they turn off the heat, and the corn steeps for eight hours.

With the kernels softened even more by the long soak, it's time to wash off a lot of the loosened pericarp.

A little pericarp still clings to the cooked corn, but that's part of the plan.

It will act as a bonding agent when the corn is shaped into tortillas.

The corn now funnels into a spiraling blade that delivers it to a grinder.

They add water and a preservative.

The auger moves the ingredients between two volcanic stones that grind everything into a corn mash.

The mash has a grainy texture similar to couscous.

That changes when they press it through an extruder.

The extruder kneads it into a dough called masa.

As the masa exits the machine, it's collected by a worker.

He transfers the corn dough to a machine called a pre-sheeter.

Here, automated paddles push the masa between two sets of rollers.

The rollers press it into a thick sheet.

The sheet of dough travels through another machine called the sheeter cutter.

In this machine, more rollers squeeze the dough paper-thin as a die cuts out round tortilla shapes.

They roll and cut 84,000 tortillas an hour on the sheet cutter.

Another big roller takes up the matrix to be reused in the next batch of dough, as the cut tortillas head into the oven.

Once inside, the tortillas zigzag back and forth on three tiers of conveyors.

The lowest tier has the lowest temperature, and the top tier, the highest.

This three-tiered approach gradually bakes the tortillas in just 21 seconds, producing corn tortillas with just the right consistency.

A vacuum system suctions the tortillas to the next conveyor to keep them from falling off, as they now head to a cooling station.

Here, the tortillas again move to and fro-- this time on nine conveyor tiers to cool.

From a handful of corn kernels to a piece of round unleavened bread, once the corn has been cooked, the transformation happens in just minutes.

Whether the tortilla is made from white corn, yellow corn, or dyed other colors, the taste will be much the same.

Exiting the cooling zone, the tortillas move into lanes.

These lanes orient the tortillas in single file so they land in slots and stack up neatly.

A sensor keeps a running count, and when there's a pile of 40, a trapdoor opens and sends them to the packaging line.

These tortillas are now ready to add a little latin sizzle to the menu.

Packaged in stacks of 80, they're headed for restaurants and cafeterias-- fried, steamed, or just warmed in the oven.

When they start adding the fillings, things could get spicy.

In every vehicle, there are rotating shafts.

The crankshaft converts the pistons' vertical action into the circular motion that drives the wheels.

At the same time, the camshaft turns to open and close airflow valves.

These precision parts are behind every successful start-up.

Life on the road can be tough, and a good crankshaft has to keep on turning when the engine is under stress.

The crankshaft starts with a forged steel shape.

A computerized blade shaves off excess metal from sections called counterweights.

They offset the load of the engine's pistons and connecting rods, and this process slims them down to create a balance.

A computerized drill bores holes into one of the bearings to reduce the overall weight.

Next a worker removes marks the computerized tools have left on the metal.

He sands the entire crankshaft.

The surface must be completely flawless for it to operate smoothly.

Fine glass beads blast the part as it revolves in a rotisserie-like device to knock off sharp edges and give the crankshaft a consistent finish.

The crankshaft then spins in a lathe, as a blade slices away a precise amount of metal from each of the counterweights.

This machining provides enough clearance for the engine's pistons and rods to function.

The crankshaft then takes another spin in a device that has sensors to detect any imbalance.

It calculates that just over 29 grams of metal still needs to be removed.

Once the adjustment has been made, he measures the degree of straightness.

If it's off even slightly, he corrects it by applying pressure with a press and tapping a special radius chisel.

He then measures again to confirm he's done an even job.

On the left is a crankshaft that hasn't been balanced or straightened.

On the right is one that has.

Production now moves to the engine's other rotating shaft-- the camshaft.

Machining transforms a steel billet into the basic shape.

Like the crankshaft, this camshaft will need a lot of fine-tuning.

An automated tool first etches the part number and date onto one end, and then they get down to the precision work.

The camshaft must also be completely straight, so the technician measures it from one end to the other and makes adjustments where needed.

Next he selects a master template of a camshaft lobe and places it in a grinding machine.

This master is the pattern to be copied by a grinding wheel.

Once it's been locked in place, he activates the grinder.

It carves into the camshaft as it rotates and rocks back and forth in the machine.

The grinding wheel moves down the camshaft to shape all 16 lobes to the exact contours of the template.

This is how the camshaft looked before the master grinding...

And after.

Next a computerized probe measures the profile of each lobe and confirms that the dimensions and lift are identical.

At the next station, the camshaft spins to allow a worker to completely coat the journal bearings with a blue dye.

The dye masks the bearings to keep them smooth while the rest of the camshaft is being parkerized.

Parkerizing will give the camshaft an etched finish, which protects against wear.

They start with a quick rinse.

Then they plunge the camshafts into hot phosphorus acid.

The acid microscopically etches the metal while other chemicals in the bath add a thin graphite coating.

They rinse the residue.

After the finish has dried, a worker buffs the journal bearings as the camshaft spins.

This completely rubs off the blue dye and polishes the metal.

He then wipes down the entire camshaft with a dry rag.

He places the camshaft on a perforated metal shelf and floods it with oil.

Some oil drains away, but a residue clings to the part, and that residue will prevent rusting.

Once packaged, this rotating shaft is on its way to a garage or car factory, where, ultimately, it will do its part to help set the wheels in motion.

Bush planes are designed to fly in and out of remote areas.

They're engineered to be able to take off and land on short runways.

They can also be outfitted with floats to be able to land on water or skis to land on snow.

Some are made of metal, and others of tube and fabric construction.

A bush plane starts out as a design on paper.

This company handcrafts four-seater tube and fabric models-- the tubes forming the airplane's skeleton, the fabric, its skin.

Welders construct a tubular frame for the fuselage, the plane's main body.

The tubes are chromoly, a type of steel that contains chromium and molybdenum, which makes it stronger than standard steel.

Machinists make the aluminum fuel-tank components...

And prepare the landing gear.

Here, they're threading the axle for the tail wheel-- a small, rugged wheel at the back, which helps steer the airplane on the ground.

The landing gear consists of this tail wheel and two bigger wheels at the front.

They all have large low-pressure tires, which enable the plane to take off and land on rough terrain.

Workers spray aluminum pieces called ribs and spars with anti-corrosion paint, then rivet them together to build the internal structure of the wings.

Using a crimping tool, they make tiny indentations in the ribs to perfect the alignment.

Then they rivet on a skin of aluminum panels, about 1/50 of an inch thick in most areas.

They construct the wing's hinged surface, the flaps, and ailerons the same way.

The factory's paint shop sprays the wings, flaps, and ailerons with highly durable urethane paint, and the fuselage frame with powder-coat paint, which is then baked on for extra durability.

Now for the meticulous job of applying the fabric skin.

The material is heat-shrinkable polyester, commonly used in the aircraft industry because it's thin, lightweight, and exceptionally strong.

Workers brush an adhesive similar to contact cement onto the painted tubing, then adhere the fabric, working around the frame section by section.

Once the fuselage is completely covered, they run a hot iron over the fabric.

This shrinks it taut around the framework.

After letting the adhesive dry for a couple of hours, they take strips of fabric, coat them with a urethane-based adhesive, and reinforce the seams.

It's the same construction process for the tail components.

At the front of the fuselage now, they install the pedals, which control both the brakes and the rudder, which moves the tail from right to left.

Then the cockpit instrument panel, a thin sheet of aluminum with laser-cut openings for all the flight instrumentation.

Next two linked control yokes.

They move a series of chains, which maneuver certain components such as the aileron control sprockets.

Mechanics ran the fuel lines and most of the wiring within the fuselage frame prior to the fabric application.

Now they install a stainless-steel fire wall between the cockpit and the engine.

This seals the cockpit from engine heat, noise, and exhaust gases.

After installing the landing gear, brakes, and windshield, workers mount the engine and exhaust system.

Next the plane's aluminum propeller.

Other workers are busy installing the fuel tanks inside the wings.

The fuselage now goes to the paint shop.

When it comes back, workers bolt on the wings, supporting them from underneath with steel wing struts.

The wings on a bush plane are positioned higher than those on other types of aircraft to give the pilot better ground visibility.

After rigging up the flight controls and installing the interior trim, workers install the doors, plexiglas windows, and cockpit seating.

Each bush plane is inspected at every stage of the production process.

When it's completed, it undergoes a nose-to-tail final inspection.

And then a company pilot takes it out for a test flight.

A serious cyclist won't pedal just any bike.

It's got to have wheels made of strong-yet-lightweight material such as carbon fiber or aluminum.

Advanced bicycle wheels have tubing and spokes, shaped as aerodynamically as possible to lower wind resistance.

These elite-level racing wheels are made of aluminum.

They're designed to generate a smooth ride with optimum responsiveness to the rider's acceleration.

The starting material-- long, straight tubes of extruded aluminum, preshaped with a wheel-rim profile.

Workers load one extruded tube at a time into a metal bender.

The machine coils the tube around and around, forming four connected rims.

After measuring to ensure the diameter is exactly what it should be, they mount the coil tube onto a cutter.

With a single downward slice, it separates the four rims.

They fuse the cut ends later on.

First the rims need a bath in a tank of acid.

The acid removes dust and other contaminants and etches the surface of the metal, both of which help ensure full adhesion of the anti-corrosion coating they later apply.

Next a multiphase heat-treatment process.

This restructures the aluminum molecules, making the metal harder and stronger.

They join the two ends of the rim by riveting on an aluminum connector tab.

Then they weld the joint to reinforce it.

Using a sharp, vibrating cutting tool, a computer-guided machine smooths the weld line until it's nearly invisible.

This makes the rim appear seamless.

Now for that anti-corrosion coating.

The process is called anodization.

In a tank, they plate the aluminum with a protective chemical, using an electrical charge to draw the coating particles onto the rim surface.

For this model, the anodized coating is black.

However, there are several color choices.

Next a computer-guided machine shaves off a minute amount of anodized metal from nearly a third of the rim surface.

This creates a smooth, perfectly flat area for the brake pads to grip.

The next computer-guided machine drills holes for the tiny aluminum nipples, which hold the aluminum spokes to the rim.

Now it's time to assemble the wheel-- a manual task entrusted to specialized bicycle technicians, as it requires a level of craftsmanship no machine can perform.

The first technician inserts a spoke into each slot of a carbon-fiber-and-aluminum flange-- part of the hub at the center of the wheel.

Once every spoke is in its respective spoke seat, as it's called, he sandwiches them with a locking ring.

Now for the rim end of the spokes.

The next technician places a small steel plug inside a spoke nipple to make it magnetic.

Then she puts the nipple into the rim, and, using a magnet, draws it to a spoke hole, then through the hole toward the inside of the wheel.

Then she removes the steel plug and inserts the free end of a spoke into the nipple.

She repeats the procedure for each spoke hole.

This is known as lacing the wheel.

The next technician holds each spoke steady while tightening its nipple with a spoke wrench.

Tightening the nipple straightens the spoke.

The process of perfectly aligning the wheel by straightening every spoke is called trueing the wheel.

This gauge tells him when the wheel is finally trued.

For quality-control assurance, this robotic machine inspects each spoke and makes any necessary tensioning adjustments.

Depending on the model, a high-end bicycle wheel can have anywhere from 10 to 46 spokes.

Different spokes for different folks.


Levels
Hot Dogs
Abrasive Grains
Sandpaper

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

Levels...

Hot dogs...

Abrasive grain...

And sandpaper.

The level was invented in the 17th century to keep structures plumb and true.

Without it, buildings would lean, floors would be crooked, and maps would have inaccurate elevation information.

No matter what you're making, this critical tool always gives it to you straight.

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

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

Production begins with a length of laminated birchwood.

An automated router carves out several holes, three of which will enclose the vials.

The other two will serve as handgrips.

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

Grooves are cut along the length of the wood for the level's brass binding.

Strips of brass are unwound into a forming machine.

Rollers iron out the curl from the coiling.

Other rollers then crimp the brass.

This process will allow the strip to fit into those grooves in the wood.

Lengths of brass binding are loaded into a machine that slides them into place.

This reinforces the edges of the wood.

Over at another station, a machine melts and molds the plastic for the vials.

Each one is slightly curved inside so the bubble has a place to sit.

The vials wind their way through a vibratory feeder.

It takes them to a gripper that rotates each one so the open end faces up.

In goes a squirt of yellow mineral spirits, leaving just enough room for a bubble to form.

A robotic arm plugs the vials with plastic caps.

Then this sonic welder melts the caps onto the vials using high-frequency sound waves.

Now it's time for inspection.

A tiny camera photographs the bubble and sends the picture to a computer that makes sure the bubbles are the right size.

For this production run, the bubble should be about half an inch wide.

If it's on the mark, the computer allows the vial to move on.

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

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

First it needs to bake for 24 hours.

The heat exposes any flaws, and the defective vials are rejected.

The vial is illuminated with a bright red light as it slowly spins between rollers.

A camera photographs the bubble, and a computer scans the image to check for shifting.

Too much shifting could compromise the level's accuracy.

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

Melted plastic is injected into the crevices to make a cradle for each vial.

Next, a technician glues the cradled vials in the openings in the wooden framework.

This is precision work.

Each vial has to sit perfectly level, so technicians rely on a magnified image to check their progress.

Some vials are installed vertically to gauge if the walls are plumb, while the horizontal ones let you know if the floor is level.

Acrylic-rimmed windows are fitted over the vials to protect them.

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

And finally, the trademark stamp goes on.

These levels are now ready to straighten up any jobsite.

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

Hot dogs are an all-american fare.

But most likely it was german sausage makers who first came up with the idea.

In fact, there are reports of german immigrants selling them from pushcarts in new york's bowery as far back as the 1860s.

A century and a half later, hot dogs are still the number-one treat on the street.

Traditional hot dogs are made from a mix of pork, beef, and chicken.

The cuts they start with are called trimmings-- pieces of meat left over from cutting steaks or pork chops.

The trimmings are ground the same way butchers chop up hamburger meat-- by pushing the cuts through grated metal plates.

Processed chicken trimmings are added to the ground meat, followed by food starch, salt, and other flavorings.

These flavorings vary depending on where the hot dogs are to be sold because people in different regions have different tastes.

Water is sprayed into the mix, and everything is blended together in a big vat.

Corn syrup adds a dash of sweetness.

The addition of even more water helps to disperse the ingredients and make the hot dogs juicier.

Another machine then purees the meat batter into a fine emulsion and vacuums out any air.

Long rolls of cellulose tubing are loaded into the stuffing machine.

It pumps the meat puree into these casings, twisting it every 5 1/4 inches-- the length of one hot dog.

It takes just 35 seconds to make a chain of hot dogs that would span a soccer field twice.

Then three of those hot-dog chains are linked together to make an even longer string, and they're loaded several at a time into another machine, which drapes the hot dogs onto moving racks.

The process is carefully timed so that a twist always lands on the bar.

The racks shunt the hot dogs through a liquid smoke shower, then into an oven with several cooking zones.

The liquid smoke seeps through the casing and adds flavor to the dogs as they bake.

Hot out of the oven, these franks are drenched in cold, salty water to chill them in preparation for packaging.

The hot dogs then file down to an unloading zone.

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

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

If you've been wondering about those black stripes on the casings, all is about to be revealed.

The stripe is a marker attached to the casing.

The absence of a black stripe means the hot dog is cooked and ready for packaging.

Inside the peeler machine, a tiny knife slits each casing along the top.

Then steamy air blows the casings right off the dogs.

This machine peels 700 hot dogs a minute.

An inspector makes sure the casing has been completely removed and that there are no defects in the dogs.

Then it's into a device that looks like a plastic bicycle chain.

The sprockets position the hot dogs for packaging.

This factory manufactures an incredible 300,000 hot dogs an hour.

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

They really do churn them out like sausages.

Fire up the grill, and a mouthwatering meal is just minutes away.

Up next, the hot scoop on abrasive grains.

It takes true grit to make sandpaper, as in abrasive grains.

People have been using abrasive minerals to sand and polish things for centuries.

Today, these minerals undergo heavy processing to make the grade, from very superfine to very coarse.

Whether you're working on metal or wood, the right grade of abrasive grit is essential for finishing the job.

The factory starts with bauxite, a naturally occurring mineral that resembles clay.

They add alumina, a white powdery material that's actually derived from bauxite.

The bauxite and alumina are blended with other minerals, then released into an electric arc furnace.

Here, three large electrodes use intense electrical current to heat the mix to over 3,600 degrees fahrenheit.

That's hotter than an active volcano.

In fact, the mixture looks a lot like lava as the minerals melt and blend together.

Standing well back and using a long ladle, a technician takes a sample for chemical analysis.

If the mix is right, the molten minerals are emptied into a big steel pot.

The searing liquid weighs several tons, so a crane is needed to transport it to a cooling area.

24 hours later, with the material hardened, it's time to bring in the wrecking ball.

It cracks open the hardened concoction, which is still quite hot at the core.

The wrecking ball is dropped repeatedly to break up the hardened minerals.

Next, the lumps of abrasive material are transferred to a conveyor system.

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

A magnet picks up any excess iron.

And then it's into the roll crusher, where iron cylinders grind the chunks to bits.

Workers assemble screens in decreasing mesh sizes to make a kind of shaking sieve.

It sifts the mineral particles through the screen with largest mesh first, then continues to sort the grits in progressively smaller sizes.

For some perspective, we placed a quarter against the various mesh sizes.

As you can see, only the finest particles could pass through tightest weave.

The bits of grit bounce across the screens and fall into hoppers--  a different one for each size.

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

The smaller the grain, the finer the finish.

The finest grits are virtually microscopic.

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

A sample is funneled into a cup.

Then it's weighed.

A higher weight means the bits are densely stacked and therefore blockish in shape with blunt edges.

A lower weight means they're flat and sharp.

A different test is used for the most minuscule grits.

The particles are suspended in an an electrolyte solution.

Then an electrical charge is applied.

This allows inspectors to count and evaluate the grits via computer.

Now these abrasive grits are ready to be packaged and shipped out.

Coming up, we'll go to the sandpaper factory, where the abrasive grits meet their ultimate destiny.

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

To make sandpaper, you need a lot of grit.

There are thousands of tiny abrasive grains on a single sheet.

The whole idea is to create friction.

By rubbing the sandpaper against wood or metal, you can remove defects and create a uniform surface.

It's ironic that something so abrasive can make things look so smooth and polished.

Sandpaper often isn't made from paper at all, but fabric like poly cotton.

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

Rollers lined with rubber printers stamp product information onto the cloth.

The cloth then travels underneath the printing press, where more rollers apply a heat-setting adhesive to the unprinted side.

A computerized system measures the density of the coating to ensure that it's been applied correctly.

Then the cloth is pulled one floor down to the electrostatic pit.

Here, the environment is kept hot and humid-- perfect for applying abrasive grains to the cloth electrostatically.

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

The conveyor moves the grains under the rolling cloth and between electrodes and ground plates.

The system generates an electrical field that triggers a mini sandstorm.

Once airborne, the abrasive grains stick to the adhesive-coated cloth and become embedded in it.

This method allows for even distribution of the grains across the cloth.

The grain-coated cloth now rolls out of the pit and back up to the main level of the factory.

A technician cuts a swatch of the sandpaper, then peels away layers and makes three different cutouts-- one of the cloth alone, another of the cloth with the adhesive coating, and a third, the grain- and adhesive-coated cloth.

He weighs each cutout to confirm that the sandpaper has been formulated precisely to specification.

He also examines the gritty surface under a microscope to make sure the grains are standing up evenly.

This production run gets the go-ahead, so workers move the sandpaper through a hundred-yard-long oven.

It has three different heating zones, each progressively hotter.

The increasing heat bakes the grains into the adhesive.

The sandpaper is now rough enough, but it's not quite ready for use.

In the next step, a coat of resin is rolled over the gritty surface, binding the grains to the base.

After the resin is cured to the surface, these jumbo rolls of sandpaper are stored in a warehouse until it's time to cut them down to size.

Some rolls are sliced into big sheets.

These will be made into commercial sanding belts-- the kind used in heavy manufacturing.

Another machine punches out sanding discs.

And at this station, four rolls of sandpaper are simultaneously unwound into a machine.

It carves the four layers into rectangles.

These rectangles won't be used for sanding, but as grip tape for skateboards.

From refinishing your furniture to nose-grinding at the skate park, sandpaper will always give you an edge.

And with so many grits to choose from, there really is a sandpaper for every job.


Miniature Furniture
Garden Steam Locomotives
Hovercraft
Folding Bicycles

Selecting furniture is a matter of scale, especially when it's a dollhouse room.

Miniature furniture is sized for really small spaces.

A popular scale is 1/12 of full-sized furnishings.

But as far as attention to detail, there's no need to scale down one's expectations.

These are replicas of full-sized antiques, meticulously copied in miniature.

This grandfather clock is modeled on an 18th-century one, and for the craftsman, no detail is too small.

He first measures and cuts numerous components from pear-tree wood.

This wood's small grain scales down well to make the miniature clock look more authentic.

The parts are too thin and small to nail, so he glues them together, beginning with the front of the clock's trunk.

He applies the glue sparingly with a tiny brass tool to prevent messy overflow.

He installs the sides on the front of the clock trunk.

And he adds a substantial-looking pearwood base.

He spiffs up the front of the base with veneer paneling that's protected by a layer of tape for now.

He carves angles and trim to make it fit neatly around the paneling.

He now peels away the tape to reveal the swirled burl of the veneer wood, which has been cut from the root of a south-asian tree.

He rubs the paneling against sandpaper to smooth its surface and expose more of the wood grain.

Once the feet have been installed on the clock, he applies a strip of molding above the trunk.

The crisp profile of this limewood trim is a classic touch.

Carving a mini gable with the thin blade of a fretsaw is tricky, especially with this intricate design, called a swan neck.

He sands the edges to finish off the job.

The swan-neck gable is one of numerous little parts that, when pieced together, form the hood of the clock, which holds the face and clockworks.

He joins the hood to the trunk, and with the basic structure now complete, he glues a tiny wooden crest to the center of the swan neck.

He tapers it with a surgical scalpel.

After staining the clock a deep antique mahogany, he sands it to make it look more authentic.

He then brushes on coats of shellac sealer.

It both protects the wood and provides a smooth surface for the next finish.

After the sealer dries, he sands it a little and then applies two coats of traditional french polish.

This mix of alcohol and shellac gives the cabinetry a high-gloss finish.

Once it dries, he buffs the wood with wax to enhance the sheen.

The clock door with its exotic veneer is also stained, polished, and waxed.

Then, using tweezers, he positions tiny brass hinges on the door.

He presses little brass pins into holes in the hinge to secure it to the door.

He files the pinheads until their flush to the hinge.

He now dips the pendulum and its weights in acid, which gives them an antiqued finish.

He installs them in their compartment in the cabinetry.

He now sets the clock upright...

And paints the back basic black.

He inserts a piece of clear acrylic into the opening of the clock hood.

Acrylic has a slight wave to it that looks like old glass.

This small watch movement is what will make this miniature grandfather clock tick.

Using double-sided tape, he attaches it to the dial.

He fastens the hands to the clockwork shafts, and then he lowers the dial and clockworks into the hood compartment.

He signs the back with a paint-filled pen which makes his signature stand out against the black background.

And finally, he glues a tiny tassel to the door handle.

Including drying time for the various finishes, it has taken over three days to make this miniature grandfather clock.

No small effort, but it's the little details that make a difference in a small space.

It's out of the basement and into the backyard for the model train set.

This trend is called garden railroading, and it merges two hobbies--  gardening and model trains.

These outdoor train sets are often larger and more rugged than indoor ones, so people can hop aboard for a tour of the perennials.

These garden-variety train sets have become the fastest-growing segment of model railroading.

People design gardens to the scale of these trains to provide the perfect backdrop.

This particular locomotive is a quarter of the size of the 19th-century original.

It starts with a sheet of copper, cut to precise measurements with a guillotine blade.

An employee then turns the crank of a machine to curl the sheet into a cylinder shape.

This cylinder will serve as the barrel or outer casing of the boiler.

The next worker assembles the boiler's internal components.

He groups together numerous copper tubes and welds them to a firebox at one end and a copper plate at the other.

He's now ready to enclose the firebox.

He installs it on a base plate and then builds a protective shell around it.

He then encases the heat tubes in the barrel.

These boilers come in various sizes, depending on the scale of the locomotive being made.

Next, a lathe spins as tools contour a bronze cylinder.

This sizes it to fit a piston that sets the steam engine's wheels in motion.

The cylinder on the right is the one that's just been machined.

More tools transform basic steel disks into the train wheels.

They make four wheels per locomotive.

The next worker inserts a pre-cut sheet of steel in a device that, when activated, bends it in two places.

The folding action shapes the sheet into the locomotive cab.

Then it's into the paint booth for seven coats of epoxy paint.

This gives this model train cab a heavy-duty gloss.

With a steady hand, a painter now applies plastic tape around the perimeter of the cab to create a kind of linear stencil.

He arcs the tape at the corners to soften the look.

And then he brushes two coats of oil-based paint into the tape stencil.

He allows three days for each coat to dry.

Then he peels off the tape to reveal the crisp, clean lines that now frame the cab.

He adds black border next to the white to give more depth to this custom paint job.

They carve a piece of bronze into a valve to control the flow of steam to the piston.

They assemble the locomotive chassis and paint it.

They install the wheels and the network of pipes and parts that make them turn.

They run compressed air through the system to confirm everything works.

The worker adds a little oil to lubricate the wheels and the rest of the parts.

He then opens the steam chamber to check the valve-and-piston action, which is the driving force of this steam locomotive.

He pulls the forward and reverse lever to confirm that the wheels run in both directions.

He applies the brakes, and the wheels grind to a halt.

Now that everything on the chassis is checked out, this steam locomotive is ready for the chimney and boiler.

The steam dome and a safety valve go on next, followed by the cab and roof.

And this garden steam locomotive is now complete.

A worker now shines a light through the boiler tubes to examine them for any obstructions.

He pokes a brush through them to be certain and then gives them the all-clear.

It's time to fire up the boiler using real coal.

Hot gases flow through the tubes to heat the water in the boiler.

Like a big kettle, this locomotive builds up steam.

The pressure increases until it's ready to roll.

Aboard one of these garden locomotive replicas, one can relive the heady days of steam engines.

A hovercraft rides on a cushion of air created by powerful fans.

This enables the craft to travel over both land and sea.

The concept actually dates back to 1870, but it wasn't until the middle of the 20th century that a british inventor perfected it and the idea got off the ground.

This model of hovercraft is equipped with a single fan.

It both inflates the skirt, lifting the vessel about 10 inches, and creates thrust to propel the hovercraft over virtually any surface.

Production begins with a hull made of lightweight polyethylene.

The fabricator installs aluminum skids on the bottom to protect the hull during landings on rough surfaces.

He screws plastic attachments for the hovercraft skirt into pre-marked positions on the hull.

The technician drills 65 holes around the hull.

The fan's air will pass through these holes to fill the hovercraft skirt.

The hull consists of a thick, hard outer layer and a low-density inner layer that makes the material buoyant.

It's what keeps the hovercraft afloat during stops on water.

The crew now fastens the seat base and console in the front of the hull.

Once it's secure, they fit the gauge panel in its slot.

The team then moves to the back of the hull to install the drive belt, pulley, and the main drive frame.

This pulley will transfer power from the engine to the fan.

Once they confirm everything moves freely, they assemble the fan to the main drive frame with high-tension bolts.

This duct will divide the fan's air into two streams.

One stream will be directed under the craft to provide lift.

The other will be routed out the back to generate thrust.

They now return to the cockpit to attach handlebars to a steering mechanism.

The engine can be either a two-stroke or four-stroke, depending on the amount of power desired.

They connect it to the drive assembly and protect that connection with metal casing.

Once the engine has been bolted into place, they equip it with a radiator...

An air filter...

An exhaust system...

And a waterproof box containing the electrical components.

Then they connect the fuel tank to the engine and cover the engine with a polyethylene hood to keep it dry.

They install seating, including a rear bench, that accommodates three.

Then the installer attaches two rudders to the fan duct.

He links them with a bar so they'll move in tandem.

These steering parts are made of marine-grade steel to prevent rusting.

A quick check confirms the rudders are operational.

The hovercraft's skirt is made of the same material used on shoe soles--  sturdy polyurethane nylon.

They assemble the skirt to the hull in 65 different pieces.

The worker loops each segment over a side bumper and secures it with a steel clip.

He then attaches the bottom of each skirt piece to the little hooks on the hull.

He uses plastic cable ties for this job, and there's a good reason.

If the skirt becomes snagged on something, these ties will break and free that section.

Then other parts of the skirt will balloon out to fill the breach and maintain the air cushion.

And they also won't have to replace the whole skirt, just the section that's been damaged.

After a final inspection, they take this hovercraft for a test spin.

They check the steering and overall performance and enjoy gliding on air.

A folding bicycle is a compact set of wheels.

In seconds, it folds up into a neat little bundle, less than a third of its full size.

The concept has been around for well over a century, and in recent years, it's on the comeback trail as urban commuters discover the advantages of downsizing this mode of transportation.

A few quick folds and this bike no longer carries the rider.

He carries it.

The bike can then be carted onto public transit or into the office, and that makes it a handy way to get around town.

They lubricate the rim of tubing, which makes it easier for machinery to pinch that end.

The next machine uses several blades to trim the pinched end and cut a small groove.

These exact cuts will enable the team to precisely install a hinge to the tube.

Hinges are now gripped by a moving clamp that angles them for contouring and the drilling of holes for bolts.

It's computer choreographed to produce a hinge that will attach snugly to the main tube.

Once the hinge has been bonded to the main tube, a technician checks the job by exposing it to a magnetic field.

Variations in the field would indicate a flaw, but he finds none.

So next, he secures the tube on a work table so a tool can make scoops in the other end.

Scooping this end will enable it to interconnect with another part of the bike frame.

A hydraulic tool then bends the main tube to give it a slight curve so it will arch around a bicycle wheel.

You can see the difference in this before-and-after shot.

The main tube of the bike frame now undergoes a process called shot blasting.

An operator turns a crank to make the tube revolve in an enclosed chamber as nozzles blow fine grit at the hinge point.

This cleans up some of the rough patches.

A little manual filing smoothes the area around the hinge.

Smaller parts of the bicycle frame take a tumble with ceramic bits, and this agitation action improves the finish on these parts.

Further down the production line, a worker locks the main tube in a jig.

He butts a bracing tube to it at just the right angle...

And then melts metal into the joint in a process called brazing.

As the metal cools and solidifies, it seals the two parts.

He now fits the bottom bracket onto the scooped end of the main tube and brazes them together.

The frame of a folding bicycle is much more complex than that of a conventional one-piece a-frame bike.

There are six parts to assemble in tight alignment, and that means there's absolutely no room for error.

Once the main frame assembly has been painted, it's ready to be joined to the rear frame.

He attaches it by bolting the hinge.

He twists the bolts to just the right torque.

He tests the folding and unfolding action of the rear assembly and then checks the lock to confirm that it functions properly.

He installs the steering mechanism and wheel fork in the front of the frame...

And bolts the front wheel to the fork.

He verifies that the assembled steering column and handlebars are in working order...

And then slides them into place at the front of the bicycle.

He adjusts the position of the column so it folds at just the right angle.

He then attaches the rear wheel, along with the gear hub, to the frame.

He secures the chain wheel and pedals to the bicycle and fits the chain into the sprockets, joining the two ends so the chain will travel in a perpetual loop.

He flips the bicycle around to install the seat, and it's time to fold.

The rear frame flips neatly under the main tube assembly.

The front wheel locks on to the rear frame.

Sliding the seat pillar down locks the fold, and he lowers the steering column.

After a final inspection, this folding bicycle is ready for the big city.

And when dodging traffic becomes too much of a hassle, its owner can always fold it and take public transit.


Navajo Rugs
Crude Oil
Kaleidoscopes
Titanium Dental Implants

Rug weaving is a traditional art practiced by the navajo, an indian nation located in the united states where colorado, new mexico, utah, and arizona intersect.

They originally wove blankets and clothing.

Then, in the early 1800s, they began weaving rugs for sale.

While many weavers create contemporary designs, navajo rugs typically feature bold geometric patterns.

The wool-preparation and weaving techniques developed by the weavers' ancestors have been proudly passed down from generation to generation.

Everything in a navajo rug comes from nature, starting with fleece--  raw wool sheared from a sheep.

Working a handful at a time, the weaver removes the mats and tangles and places the wool on carders-- wooden paddles with metal teeth.

By pulling one carder against the other, she straightens the wool fibers, lining them up in the same direction.

This prepares them to be spun into one continuous strand of yarn.

After three or four pulls, she flips the carders to straighten the fibers on the underside.

Then she rolls up the fleece and adds it to the other rolls in the spinning pile.

She spins the fleece one roll at a time with the traditional spindle that she lays against her thigh and rotates towards her with one hand.

This movement twists the carded roll of fleece into a strand.

When she reaches the end of the roll, she connects another and resumes spinning and keeps repeating this process until she's produced one long, continuous strand from about 50 rolls.

Then she respins the strand to thin it out to the final weaving size.

When she's done, she checks the entire length of the strand, pulling on the thicker areas to thin them out so that the entire strand is a consistent size from one end to the other.

Here you can see the difference in thickness between the first spinning and the second.

To infuse her wool with color, she prepares natural dyes-- sunflowers for yellow, walnuts for tan and brown hues, and cactus bugs for bright red.

She puts the bugs in a stocking and soaks them in warm water overnight.

Then, she submerges them in a pot of water, pours in the presoak water, as well, and simmers for 45 minutes to an hour and a half, depending on how vibrant she wants the red dye to be.

Meanwhile, she soaks the yarn in warm water for at least a half-hour to open up the fibers so that they'll absorb the dye.

After wringing out the yarn, she immerses it in the pot of hot dye and simmers for at least 45 minutes, depending on the amount of bugs, water, and wool.

She stirs frequently to ensure it dyes evenly throughout.

It's the same process with plant dyes, except that she doesn't presoak the plants overnight before boiling them in water.

The shade of color depends on the ratio of plants to water during dye preparation, then of dye to the quantity of wool.

Proportionally more plants than dye, the darker the shade.

Proportionately less, the lighter the shade.

Sunflowers and walnuts are just two of many plants the navajo have traditionally used to produce a rainbow of dyes for their textiles.

With her wool now spun and dyed, the weaver picks up her weaving comb and begins.

Navajo ancestors used trees as the sides of their looms.

Today's weavers make looms from lumber or metal pipes.

After stringing tight, vertical strands of wool called the warp, she uses a flat, handmade stick called a batten to pry a wide enough opening through which to pass her hand with the colored weaving wool.

She weaves horizontally in and out between the warp first in one direction, then in the other.

Then, she packs down the wool tightly with her comb so that the warp doesn't show.

She mostly eyeballs the emerging unique pattern, occasionally counting vertical strands to calculate the symmetry, a signature feature of traditional navajo rugs.

Crude oil, also called petroleum, is unprocessed oil found deep in the ground.

It forms naturally from decomposed, prehistoric plants and animals.

The color can range from clear to black, the consistency from very watery to very thick.

Oil companies drill wells deep into the ground then install pumping units to draw up the fluid that contains crude oil and salty water.

This oil field in central california has 6,000 producing wells.

The pumping units can run 24 hours a day.

However, a sensor triggers them to pump only when the fluid flow stops.

Here's what goes on inside the well.

With each downstroke, the pumping unit pushes a steel rod down the steel tube lining the well.

With each upstroke, the rod rises, and the pressure difference between the fluid on the outside and fluid on the inside opens a ball-shaped valve plugging the bottom, letting the fluid flow up the tube.

Another valve at the top releases the fluid out of the well.

To drill a new well, workers first erect a drilling rig at the site then hoist a giant pipe with a drill bit on the end.

They feed this drill pipe through the center of a spinning disk called a rotary table.

As the table turns, the drill pipe turns, its weight bearing down and boring a hole through the ground.

Once the drill pipe descends its full 30-foot length, they connect another pipe then keep repeating with subsequent drill pipes until they bore into the reservoir containing fluid.

Throughout the drilling process, they pump a mud mixture down the drill pipe.

It comes out the drill bit at the end, hits the bottom of the hole, then backs up to the top, bringing the drilled-out rock with it.

After lining the well with a steel tube to keep the walls from collapsing inward, they mount the pumping unit and install the valves we saw in the model.

The pumping unit pushes the rod up and down through the well head at the surface.

As a safety measure, workers take readings to check the air for any hazardous underground gases that may be exiting the well.

Once they determine the area is safe, they draw a sample of fluid to test the well's water-to-oil ratio.

The typical ratio is 90% water to 10% oil.

The fluid from each well exits via a pipe, and the pipes from all the wells feed a main line leading to a gas-removal vessel.

The fluid contains carbon dioxide, hydrogen sulfide, and natural gas.

They naturally rise to the top of the vessel and exit via a pipe which runs to the company's gas-treatment plant.

There, equipment removes and treats the hydrogen sulfide, transforming it into sulfur, which a local farm buys to use as fertilizer.

The natural gas and co2, meanwhile, are piped to another area, where they fuel the company's steam generator.

The generator boils the water extracted from the fluid to produce steam.

The company injects steam into the wells to heat the fluid, thinning it so that it flows faster.

Once gasless, the fluid is piped to the treatment plant that extracts the salty water.

In this big tank, appropriately called the free-water knockout, the separation of oil and water happens naturally, the oil floating to the top.

However, to hasten that natural process, they add a chemical called an emulsion breaker.

The extracted water exits via a pipe leading to the steam generator.

The oil goes to a clarification tank in which a chemical process filters out sand, which the fluid brought up from the reservoir.

The emulsion breaker added in the previous tank continues to extract water.

By the end, when the ratio is 98% oil to 2% water or better, the crude oil is ready to sell.

Built-in meters give instantaneous water-content readings.

As an additional quality-control measure, however, the company also draws samples for analysis in its onsite lab.

In fact, there's testing throughout production to ensure sufficient water is being extracted at each phase of processing.

Refineries buy crude oil as a raw material for producing gasoline, asphalt, plastics, and many other products.

Invented in the early 19th century by a scottish scientist studying light, the kaleidoscope can still compete when it comes to producing stunning visual effects.

Peer inside and witness dazzling geometric images produced as mirrors multiply objects.

The images are spectacular and fleeting, each one lasting just seconds before the next appears.

Many years after its invention, the kaleidoscope is still worth looking into.

To make a kaleidoscope, this craftsman starts with a mirror sheet that has adhesive backing.

He scores it to create long and narrow rectangles and gently breaks it along the scored lines.

The mirror's reflective coating is on the front instead of the underside.

A mirror like this produces sharper reflections than a regular household mirror.

He slices the adhesive backing to separate the mirrored rectangles.

He snaps off the scored ends, creating perfectly linear edges.

Next, he peels backing from a strip of black-out felt paper and wraps it around a glass rectangle.

This felt-wrapped glass will be the third wall of a two-mirror system-- one with a triangular configuration.

He removes the adhesive film from the mirrors then builds the triangles with the mirrors' reflective surfaces facing inward towards the felt-wrapped rectangle.

This arrangement will reflect objects to create a circular image known as a mandala.

He aims the mirror system at a light box with a two-line drawing in it.

One line is curved, and the other is straight.

Peering into it, he adjusts the alignment of the mirrors until the lines morph into a five-point star.

This means the corners of the mirror triangle are precisely 36 degrees and it is multiplying images correctly.

He hot-glues the mirrors to the opaque part and applies metal tape to the top seam to complete the kaleidoscope mirror system.

Over in the art department, the artist assembles decorative objects against a black background in an acrylic cell.

With every placement, she checks the effect through the triangular mirror system.

She glues dichroic glass onto the backdrop.

It's a kind of glass that's been treated with metal oxides, and it appears to have different hues.

Other objects include jewelry parts, colored wire, buttons, and even paper clips.

She follows no specific design but works freestyle.

While she glues some down, she leaves others loose to simply tumble around.

A sprinkle of tiny beads completes the grouping.

As the mirror system multiplies these objects, they will create the mandalas.

These are photographs of actual mandalas, and they'll be used to decorate the outside of the kaleidoscope.

The other member of the team now applies an acrylic adhesive to the rim of the cell and presses a clear lid onto it.

The lid fuses to the cell body.

But it's not yet completely sealed.

There's a tiny hole in the side of the cell through which he now dispenses heavy mineral oil.

Submerged in mineral oil, the objects will float and move through the cell for greater effect.

He plugs the hole with an acrylic adhesive and screw.

He is now ready to assemble all the parts of the kaleidoscope.

He slides the mirror system into a heavy cardboard tube decorated by the mandala photos.

He cushions the mirror system with foam, and this stabilizes it.

He installs a metal eyepiece and glass lens on one end of the kaleidoscope tube.

He slides the object cell into a protective metal cage that rotates.

He places a transparent glass disk over the cell.

He applies adhesive to the cage and inserts the assembly into the other end of the kaleidoscope tube.

This kaleidoscope is now ready for a viewing.

Light passes through the object cell, illuminating the trinkets.

Reflections bounce off the mirrors to create one spectacular illusion after another.

Two centuries after its invention, the view through the kaleidoscope still fascinates.

The ancient mayans hammered seashells into their jaws to replace missing teeth.

Those seashells were likely the first dental implants.

Today, titanium tooth implants fill the gaps nicely, and, usually, the patient's jawbone will actually bond to them.

In the middle of the 20th century, it was discovered that titanium is a metal that bonds with bone.

It revolutionized restorative dentistry, making enduring tooth implants possible.

To make these implants, they start with a solid titanium rod.

This 13-foot rod will be used to make more than 200 implants.

The technician inserts the rod in a long tubular device that keeps it straight as it feeds to a lathe system.

The titanium rod spins as computerized tools slim it down and cut threads into it.

These threads will help anchor the implants in the patient's jaw.

The lathe pushes the rod out and then pulls it back in repeatedly to facilitate the shaping process.

A tool now grips the implant while another cuts it to length.

Then, a computerized drill hollows out the implant and carves threads inside for attaching the ceramic tooth.

In minutes, a solid, metal cylinder becomes a hollowed and threaded implant.

A robot now retrieves the implant from the clutches of another one.

It transfers it to a cleaning station and then over to what's known as a vision measuring system.

Here, a camera takes pictures of the implant from all angles and sends the images to a computer for analysis.

The computer confirms the dimensions are exactly right.

Then, the robot collects the implant and places it into a slot in a tray.

Once filled with implants, a technician screws a mesh lid on the tray and slides it into a metal basket.

The basket positions them for cleaning in a special washing machine known as a vapor degreaser.

Inside, solvent vapors envelop the parts to clean off residual lubricant oils used during the cutting process.

A robot transfers an implant to a holding device.

The device secures the implant for the next robot to press a plastic collar onto it.

This collar is temporary.

It will serve as a mask to protect the outside of the implant as the top undergoes a process of colorization.

A robot places the implant upside down in a mild acid.

They apply an electrical charge.

Different colors will appear at different voltages to color-code the part and indicate the diameter.

The process is called anodizing.

A robot now pulls off the masking collar.

It transfers the implants to another tray and screws them onto it.

This keeps them from falling off as machinery turns the tray upside down to immerse the implants in acid and anodize the exterior.

This time, the anodizing serves another purpose.

It changes the surface to make it more porous.

This will improve the bonding of the patient's jawbone to the implant.

The implant sparkles in the solution as it undergoes a transformation.

Here's the new porous surface magnified by a microscope.

A robot transfers the dental implants to another tray.

They're now ready for a final cleaning.

A technician puts a lid on the tray and lowers it into a tank full of hot, purified water.

A generator sends high-frequency sound waves into the water, creating bubbles and waves that gently scrub the implants.

After sterilization, these titanium dental implants are ready to take root in human jaws.

The clinician screws the implant into the patient's jawbone and then secures a made-to-match ceramic tooth to it.

Over time, bone will fuse to this artificial tooth, providing a long-lasting tooth replacement and giving the patient a reason to smile.


Digital Dentistry
Nail Clippers
Poster Restoration
Canola Oil

Digital technology is revolutionizing dental treatment.

3-d cameras and computers can now be used to produce crowns and other prosthetic restorations on site, eliminating the need to send the work to an outside lab.

For the patient, it means one appointment instead of two and less time in the dentist's chair.

With computer-driven tools, custom restorations take shape in a matter of minutes while the patient waits.

After donning dark safety glasses, the patient is ready for her close-up.

The dental assistant inserts a small video camera in her mouth to examine the problem area.

She then inserts a strip of carbon paper between the patient's teeth and instructs her to clench her teeth.

This leaves markings that indicate her bite profile.

The dentist meets the patient and reviews her case.

They agree to replace the silver filling with a ceramic inlay that will strengthen the tooth for much longer than a regular filling would.

He anesthetizes the tooth and the gums that surround it.

He then stretches a rubber dam across her mouth and exposes the area to be treated through a slit.

This keeps filling fragments out of the patient's mouth as he drills.

He switches to a smaller drill bit to excavate the remaining filling particles and to remove decay.

Each cavity must be completely clear before the restorative work can begin.

The dental assistant then scrubs an antimicrobial solution into the tooth.

Then she brushes an acidic conditioner into the cavity.

The dentist activates the conditioner with a halogen light.

He points a high-resolution l.e.d. camera at the tooth and downloads the image onto a computer, which converts it to 3-d.

Next, the dentist fills the cavity with the silicone putty.

When her teeth come together, they leave an impression in the putty that indicates her bite profile.

Once the putty hardens, the dentist and his assistant chip off the excess.

He downloads the image of the bite impression and then superimposes the images as he designs a custom dental inlay digitally.

The dental assistant selects a glass ceramic block of the appropriate size and color.

She anchors the block in a milling chamber and shuts the lid.

Two computerized drills now sculpt the block into the dental inlay, guided by the digitally produced design.

This process takes less than 10 minutes.

The dentist then pulls the ceramic inlay from the base.

This leaves a small nub that he then grinds away.

Next, using rubber wheels and diamond-impregnated brushes, he polishes the entire restoration to a high gloss.

He conditions the inlay with hydrofluoric acid to prepare it for adhesion to the tooth.

He dips the filling in water, and the hardened solution flakes off.

He then thoroughly dries the inlay.

Next, he adds a drop of silane that will promote the bonding of the inlay to the tooth.

The dentist injects tooth-colored resin cement into the cavity.

He presses the digitally designed and milled inlay into the cement, then scrapes away the overflow.

Halogen light on the dental work hardens the cement.

He takes another impression of the patient's bite to confirm the new inlay is perfect.

Finally, the dentist polishes the contours of the ceramic inlay.

And it's time for the reveal.

He uses the camera to magnify the new dental work for the patient's scrutiny.

It's taken just an hour and a quarter for her custom restoration to be designed, milled, and installed, all thanks to digital dentistry.

The nail clipper was invented in 1896 in the united states, and soon it was at everyone's fingertips.

By 1902 it, ads marketed it as the "gem," and it was sold by the dozen for $2.

As an alternative to scissors, it was the idea that just clicked.

More than a century after its invention, the nail clipper is still behind many a well-groomed hand.

Its popularity numbers in the millions, and no manicure set would be complete without one.

Production begins with this elaborate dye.

It's about a yard in length and has 12 different-shaped openings.

Hydraulic machinery repeatedly forces a steel sheet through the various openings as the sheet moves forward.

With each stroke, the parts look more like nail-clipper jaws.

The clipping edge starts out straight and blunt and gradually becomes concave.

The machinery also cuts and shapes the holes for assembling the nail clippers.

In just one minute, a total of 80 strokes generate a dozen nail-clipper jaws.

Here, the clipper jaws vibrate with abrasive stones and organic acid for up to 20 hours.

This gentle polishing makes the parts gleam, but doesn't ruin the edges and contours.

At the next station, a worker aligns pairs of clipper jaws for assembly.

Using a mechanical press, he drives a rivet into the hole at the gripping end of the jaws.

He flips the assembled clipper jaws over, inserts the other half of the rivet, and then presses the two tightly together.

The rivet locks the gripping end of the nail clippers together so that the two jaws can't be twisted apart.

Next, a worker smoothes the edges of the clipper's gripping end against an abrasive wheel.

This grinding evens out any irregularities and makes the two clipper jaws appear as one at the gripping end.

Attention now turns to the cutting end of the clippers.

After locking them in a device, a worker grinds the concave edges until they match up.

These nail-clipper jaws are now ready for the lever, but the lever itself still needs some work.

Using a little press, they make a whole and an indentation between its two prongs, allowing the lever to sit more comfortably on the clipper.

Levers are then fed one at a time to a set of drills that carve little holes into the prongs of the fork.

The holes are just big enough for a pin that's 0.05 of an inch in diameter.

Here's the view from the side before and after drilling.

A worker now inserts a bolt in the cutting end of the clipper jaws.

This bolt has a little hole in the end of it.

He presses the jaws together, and it's now time to attach the lever.

He inserts the pin in the holes in the lever and the bolt.

He pinches the pin with pliers to secure it, and the lever now pivots freely on the cutting jaws.

All the pieces of the nail clipper have come together, but the assembly processes have left oil and other residues on this tool.

It's time for a cleaning in a special tub.

Sound waves keep the water moving to distribute the soap and scrub them clean.

Once they dry, a worker uses a combination of acid and positive electrodes to etch the company name and item number onto the nail clipper.

The next employee sands the cutting edges to sharpen them.

It takes skill and practice to get them just right.

He holds the nail clipper to a light and scrutinizes the alignment of the jaws as he opens and closes them.

This cardboard test confirms that these nail clippers are up to the job.

From a blunt clipper on the left to a really sharp tool on the right, what a difference the sanding has made.

The lever swivels for various clipping angles and then folds down neatly when not in use.

It takes 11 people to manufacture 100 of these clippers an hour, and that means they've been working at a very fast clip.

Long before the internet and electronic media, the poster was an important means of communication.

These lithographed notices were used to sell everything from soap to political propaganda.

Today they're being painstakingly restored to preserve both the artistry and history behind them.

These are the signs of a different time.

And decades later, the bold artistry of these poster lithographs is still an attention grabber.

Some vintage posters can be worth tens of thousands of dollars, which makes them worth restoring and preserving.

Posters often become brittle and break along the fold lines.

So first, this restoration specialist reassembles the torn sections and examines them to determine if this poster can be saved.

He decides to proceed.

He loosens old tape with solvent and carefully peels it away.

Next, he separates the poster sections with plastic mesh-- to keep them from sticking together-- in a bleach bath.

The bleach gently removes dirt and mildew to reveal the vintage poster's original colors.

He presses out air pockets between the layers to maximize its effect.

While the pieces of this poster dry, he prepares a paste of water, wheat, and calcium.

The calcium will counteract the acid in the vintage paper, preventing further deterioration.

He rolls the wheat paste onto a big sheet of acid-free paper.

And he spreads more paste on a piece of linen-textured cotton.

He then presses the paper to the fabric, and they adhere.

He now has a big piece of fabric-backed paper.

He rolls out the air bubbles and excess paste for a more even surface.

He now reconstructs the poster on the fabric-backed paper, which is now saturated with glue.

He works carefully and quickly to put the pieces together before the glue dries.

One false move and he could make a real mess of things.

But experience pays off.

He aligns the four sections perfectly.

The glue dries, giving the vintage poster a solid backing.

He flips through a collection of paper scraps in search of one that's similar in texture and thickness to the posters.

He'll now use it to repair the poster's ripped corner.

He traces the outline of the tear onto transparent paper.

He cuts the scrap paper along the traced line, producing a new corner for the poster-- one with exactly the right profile.

He sands the edge a bit to give it a more gradual slope.

He brushes vegetable-based glue onto the cutout.

He aligns it with the torn edge and glues it in place, then flattens the new corner to make it level with the rest of the poster.

It's now time to complete the picture by repairing the torn images.

The tricky part is mixing the paint to match the poster's vintage colors.

It sometimes takes a few tries to get it right and make the repair blend in.

Even the white on the border has to match.

No detail is overlooked as he restores the corner of this poster to its original condition.

He touches up the rest of the artwork with watercolor pencils, applying color heavily or lightly where needed.

And with a practiced hand, he makes all the flaws and fold lines disappear.

By the time he's done, the vintage poster will look good enough to frame.

With all the details now covered, he trims the poster on all sides and examines his work for imperfections.

The repairs have to both look and feel real.

From a tattered relic of the past to one that looks fresh off the press, a restored vintage poster is an important piece of history, now preserved for future generations.

Canola oil is a commonly used type of cooking oil.

It's derived from the seed of the canola plant, which north american farmers have been growing for about 30 years now.

The plant blooms in the summer, producing bright yellow flowers.

Farmers harvest the seeds from pods which form after those flowers die off.

Canola oil is one of the healthiest cooking oils.

Compared to olive, sunflower, and soybean oils, it has the lowest level of saturated fat-- 7%.

It also contains more healthy omega-3 fatty acids and is high in monounsaturated fat, which lowers cholesterol.

When the canola seed arrives at the processing factory, it contains foreign material-- mostly plant pieces.

So the first step is to clean the seeds in a vibrating sieve.

The seeds-- smaller than the openings in the sieve's mesh-- fall through to a conveyor below.

The foreign material remains on top.

A conveyor moves it to a storage bin, where it's collected for sale as cattle feed.

The seeds pass by a magnet.

It removes any metal that may have fallen in during the journey from field to factory.

Next, the seeds enter a roller mill.

They pass between two steel rollers, which crush them into thin flakes.

A conveyor then feeds the flakes into a screw press.

It has a large revolving screw-shaped shaft enclosed within a slotted cage.

As the shaft turns, its threads squeeze the flakes with high pressure, forcing out the oil, which then drains out through the slots.

42% of canola seed is oil.

This group press extracts nearly 3/4 of that.

The remainder is still trapped in the pressed flakes, now referred to as canola cake.

The cake exits the other end of the press and moves on to a second extraction, this one a 70-minute wash with a solvent.

This chemical-extraction process removes all but a trace of oil.

The factory then grinds the cake into protein-rich meal that it sells as animal feed.

The extracted oil, stored in large tanks, now enters the refining phase.

First, they wash the oil for 20 minutes with sodium hydroxide.

During this wash cycle, they spin the oil at high speed so that the centrifugal force separates the natural impurities, which the factory later sells to soap manufacturers.

After this cleaning process, the canola oil is visibly clearer.

However, it still contains natural waxes, which makes it look cloudy.

So the next step is to cool the oil to 41 degrees fahrenheit.

This thickens those waxes so that they can be filtered out.

The waxes don't go to waste, either.

The factory uses them to produce vegetable shortening.

In the factory's lab, technicians recreate production on a small scale to ensure performance and quality.

Meanwhile, back in the factory, after washing and filtering the oil, they bleach it to lighten the color, then use a steam-injection heating process to remove the canola odor.

The oil is now fully refined and ready for bottling.

The equipment first turns the plastic bottles upside down and injects filtered pressurized air to blow out any dust or dirt inside.

Then it turns the bottles right side up again to position for filling.

Just before a nozzle starts filling, it applies a vacuum.

If there's no suction, indicating a leak in the bottle, the machine automatically ejects that bottle from the line.

Each bottling machine in the factory fills 22,000 bottles per hour.

The labeling machines work at the same speed.

They spread glue on the back of each label, then apply the label's edge to the bottle.

The bottle spins, wrapping the rest of the label around itself.

As the bottles come off the labeler, a robot separates them into groups of 12.

Then it picks up and deposits each dozen in a shipping box-- from field to factory to your pantry, where, once opened, canola oil has a shelf life of about a year.


Industrial Wire Ropes
Living Walls
Large Format Cameras
Gemstones

Industrial machines often have heavy loads to lift or pull.

Whether it's a dragline excavator working in an open-pit mine, an oil-drilling rig, a construction crane, or farm machinery, the weight is borne by ultrastrong wire ropes.

Industrial-wire ropes typically range from 8/10" to 5" in diameter.

Besides machinery applications, they also serve as support cables for large static structures, such as bridges and stadium roofs.

Manufacturing a wire rope begins with steel wire that's anywhere from 3/1,000" to 3/10" in diameter.

The first step is to wind several of these wires together into a strand.

How many wires per strand depends on the job the rope will perform, because different applications require different degrees of flexibility and strength.

Each wire is spooled onto a steel bobbin and loaded onto a stranding machine, which is essentially a giant winder.

There can be as many as 64 wires in a strand, although the typical range is between 19 and 36.

The twisting wires converge in a die that forms them to the required diameter.

Lubrication is critical, and not merely to help the wires move smoothly through the die.

It also penetrates within to allow slight movement between the wires.

This increases their life span and prevents the strand from seizing.

The strand exits the machine saturated in lubricant.

A large rubber band skims the excess off the surface.

The strand now travels through a row of straighteners.

These heavy rollers apply vertical pressure, effectively erasing the wire's memory of being spooled on a bobbin prior to stranding.

This prevents the wires from unraveling.

This cross-section shows all the wires inside the finished strand.

The clothespin gives you a sense of its size.

Wire strands are by themselves typically used as structural support cables.

To make wire ropes used in machinery and for heavy lifting, they take several of these wire strands and wind them together on a far bigger and stronger machine called a closer.

They make this particular rope from six wire strands.

Before the strands converge in the die, rollers pre-shape them into a corkscrew-like form.

The strands then enter the die, twisting together over a core, which is itself a small steel-wire rope.

A core at the center of the cable provides additional strength.

This cable's finished diameter is 3 1/2".

However, there are always small variations here and there, so now four calibration rollers, two compressing vertically, two horizontally, correct the cable to the right diameter all along its length.

The finished cable winds onto a big steel reel, ready for shipping.

The factory tests random samples in its quality-control lab.

There, a machine measures the tensile strength-- how much pulling force the cable can withstand.

The machine pulls the cable at both ends until it snaps.

for this mega cable, the breaking point was 104 tons.

To pass the test, a cable must exceed the tensile strength it's designed to withstand.

For certain demanding applications, such as mining, wire ropes are double-coated in plastic to protect against wear and tear.

To prepare the plastic, the factory mixes a recipe of clear and colored plastic pellets.

An extrusion machine heats the pellets until they liquefy, then forces the molten plastic through a die, coating the rope as it passes through.

As the rope exits the extrusion machine, it passes through water, which cools and hardens the hot plastic.

The plastic not only jackets the rope's surface, it also provides cushioning when on the jobsite, the strands inside rub against each other as the rope moves.

By reducing wear and tear on the steel both internally and externally, plastic coating can extend the life of a rope by up to 50%.

A cable's internal construction determines its strength and flexibility.

A structural one needs to be strong, immobile, and taut, so it's a single strand made of large wires, whereas a moving rope and large machinery contains many strands made of smaller wires.

A living wall is a vertical structure covered with fully grown plants.

This green screen serves many purposes, such as hiding an eyesore or shielding an area for privacy.

Some are installed in the ground, while others are mounted on building facades and have integrated irrigation systems.

Living walls are modular systems.

Each module contains fully grown plants, so upon installation, the green-screen effect is immediate.

The plants are hedera helix woerner, a variety of ivy that's highly resistant to cold and drought.

In the manufacturer's greenhouses, horticulturalists take cuttings from the mother plants...

Then cut off the foliage and separate the leaves, leaving each with a small stem.

Then they plant the cuttings five leaves to a pot.

The soil is a secret recipe of organic and nonorganic materials and feed.

Over the next month to six weeks, each stem develops a good root system.

Meanwhile, workers construct a welded frame out of high-strength carbon steel.

The metal is galvanized so it's rust-proof.

Once the frame is ready, they take a mat made from biodegradable, recycled coconut husks and fold it into a planter box, which fits inside the bottom of the frame.

Two side wires hold the box securely in place.

An automated machine fills the box with the same soil mix used for the cuttings.

Then the horticulturalists plant 13 pots of plants.

That's 65 ivies per box.

They wrap the longer stems around the uprights of the frame.

The frames now move to the greenhouse, where they're hooked up to an irrigation system.

For the next 18 months or so, the plants grow, and as they do, the horticulturalists keep wrapping the ends around the uprights.

This is called training the plants.

As the plants thicken, the nursery workers prune them to promote upward growth.

The factory produces these green-screen modules in 3 heights, ranging from about 3 to 7 feet.

After installation, the plants can grow on-site to a total height of 13 feet.

Each frame-- one module of the living-wall system-- is 4 feet wide, making it easily transportable.

At shipping time, workers load the screens 10 to a pallet and truck them to the installation site.

Each module of the system installs just like a fence.

Workers embed a wooden post on either side of where each screen will go and dig a trench that's the width and depth of the planter box running in between.

They sit the screen in the trench, then, with galvanized-steel brackets, clip it to the side posts at the top and bottom.

Then they fill in the gaps with dirt.

The screens have a 45-year life expectancy, and the leaves remain on them year-round.

This variety is used on living walls in europe and warmer regions.

In colder climates, the manufacturer uses a hardier species of ivy that stays green even throughout harsh, snowy winters.

A large-format camera is essentially great-granddad's camera, the one with accordion-style bellows, the big film, and the curtain draped around the viewfinder-- 19th century technology with some modern refinements.

For many serious photographers, the basic concept still clicks.

In an age when cameras are miniaturized and digitized, the large-format camera might seem to be a relic.

But for pros, it's a creative tool.

The flexible bellows allow for a wide range of movements for incredible control of the image.

Image quality is another attraction.

This camera uses big sheet film, 4" x 5" and up, generating big negatives that don't need to be enlarged as much during printing, so the image has better resolution.

At this factory, they mold many of the camera's parts out of plastic.

They inject liquid plastic into molds, and the parts quickly solidify.

Other parts are made of laser-cut aluminum and stainless steel.

The camera maker assembles the base first, attaching rails that slide back and forth for focusing.

The next parts allow for swing and shift action-- movements that come in handy when composing a shot.

He attaches the camera's molded, plastic body to the swing and shift assembly.

Next, he assembles the front part of the camera, which holds the lens and shutter.

It has a swing and tilt mechanism for changing a shot's depth of field.

He slides the lens holder into place and secures it.

It can be raised and lowered when composing the shot.

He inserts spirit levels into the slots in the front and rear sections of the camera.

These levels will be used to check the angle of the shot.

Moving now to the focusing screen, it's made of ground acrylic to diffuse light.

He protects the acrylic from scratches with a glass plate and secures the assembly with stainless-steel clips.

He snaps the completed focusing screen to the body of the camera, where it can be easily switched from portrait to landscape position.

He tests the focus mechanism and confirms it's operational.

He now folds and glues fabric in an accordion configuration to create expanding bellows that will link the front and rear parts of the camera.

He applies double-sided tape around the inner lip of the folded bellows.

He sticks more double-sided tape onto a plastic frame...

And peels away the tape backing in strategic locations.

He inserts the frame into the bellows and aligns it with the taped inner border.

He then completely peels off the taped backing and presses the frame to the bellows' taped rim.

This frame adds crucial rigidity to the bellows.

Using more double-sided tape and adhesive, he secures the bellows' accordion to a larger fabric bag.

Next, he glues plastic flanges to each end of the bellows.

The flanges are connector pieces for attaching the bellows to the front and rear sections of the camera.

There are two kinds of bellows.

The one with the bag attached is usually used with a lens of short focal length.

An accordion without the bag has a much longer range of extension to accommodate a bigger lens.

He now connects the back of the camera to the front with the bellows.

They are a flexible link between the two.

By expanding or retracting the bellows, the photographer can adjust the distance between the lens and film to focus the shot.

Finally, he attaches the lens to the front of the camera.

It's now ready for a film test.

He loads the film into the holder.

Normally, this is done in complete darkness to prevent exposure of the film.

But he's left the lights on for our camera.

The film slides into the holder into the camera back.

And while film still rules in large-format photography, there are now digital camera backs for photographers who want instant results with traditional focus movements of the bellows camera.

It's all a matter of focus.

Man has used gemstones since ancient times.

Genuine gemstones come from nature-- minerals, rocks, or even certain organic materials.

Shaped, cut, and polished to bring out their colors and brilliance, the rarest ones are classified as precious gems, the others as semiprecious.

This semiprecious stone is called blue john.

It's a variety of the mineral fluorite, also known as fluorspar.

While common fluorspar is cream or white, blue john also has magnificent bands of purple, blue, and yellow.

There's only one place in the world where blue john is found, and that's in the village of castleton, derbyshire, in central england.

The stone comes from a cavern located some 55 yards deep in a hillside.

The miners don't use explosives, because the stone is quite soft and brittle in its natural state, and blasting would simply shatter it.

Instead, they use drills to carefully dislodge pieces of blue john from the rock wall.

They carry the blue john to the surface to the mine's workshop, where stone processors manually wash off the clay.

The stone is wet due to having been underground for some 240 million years, so they put it into an oven at low heat-- 176 degrees fahrenheit.

When the stone comes out of the oven a couple of weeks later, all its moisture has evaporated.

The dried stone, however, is still brittle, so they submerge it in a bowl of liquid resin, then place the bowl into a vacuum oven at 176 degrees fahrenheit.

This process draws out all the air and forces the resin deep into the stone's pores.

The stone then goes into another oven at 122 degrees fahrenheit for about 12 hours.

This hardens the resin, stabilizing the stone so that it can be worked without crumbling.

To create large items, such as goblets and bowls, the workshop's artisans turn the stone on a lathe.

To avoid fracturing it, they must work the blue john slowly and with diamond-tipped tools.

Diamond, being harder than all other rocks, cuts with less force and stress.

To supply jewelry makers, the mine workshop saws stones into slices using a diamond-edged saw.

At the jewelry workshop, a gemologist examines the slices on a light box to highlight the coloring and any flaws.

This helps determine which parts of the slice will yield the most striking gemstones.

Meanwhile, in another part of the workshop, a silversmith crafts the piece of jewelry-- in this case, a sterling-silver ring which will receive the blue john gemstone.

She bends, then solders together the ends of the ring's shank, the part that encircles the finger.

After grinding the solder seam flat, she fuses the top of the ring, called the setting, onto the shank.

Then she polishes the ring and passes it onto the gemologist, who takes a slice of blue john and, with a diamond-edged lapidary saw, cuts out the gemstone's shape, making it slightly larger than the setting.

Next, she glues on a backing cut from mother-of-pearl.

Just like the white light on which the gemologist examined the blue john slices, this mother-of-pearl backing highlights the colors in the stone.

Now, using a diamond-grit grinding wheel, she shapes the stone to perfectly fit in the setting.

She applies glue to the setting and fits the gemstone snugly inside.

Once the glue dries, she uses a diamond-grit sanding belt to smooth down the edges, gradually transforming the rough oval into a sleek dome.

This gem shape is known as a cabochon.

Finally, she polishes the entire ring's surface until the silver and richly hued blue john glisten.

Whether it's one of several, the shape funky or traditional, a gemstone sure makes a piece of jewelry rock.


Nails and Staples
Safety Glasses
Fabrics
Bicycles

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

Nails and staples-- a fascinating manufacturing process.

Safety glasses-- focused on protecting your eyesight.

Fabrics-- we'll weave our way through a textile mill.

And bicycles-- we gear up to see how they're made.

If you've ever needed to attach two pieces of wood, you know there's no shortage of fasteners.

You can choose from common nails, spiral nails, finishing nails, and even staples.

And if you've ever wondered where these useful little items come from, well, we've got it all nailed down for you.

There are hundreds of varieties of nails being made, and they're made of very durable carbon steel, all starting from steel wire.

Rolled up on a drum, this steel wire weighs in at 5,500 pounds.

The wire's diameter is a quarter of an inch.

And that's too large, so they'll have to reduce its size.

Using many drums, they're going to pull the wire successively to gradually thin it.

Then they'll roll it up again.

When full, this roll will contain almost 80,000 feet of wire weighing 2,500 pounds.

The wire now has a diameter of 1/10 of an inch, so it will have to be reduced by half.

Now they're going to cut the wire into little rods.

The cut rods are gathered up with this electromagnet and dumped into a machine that will process them.

Here, the rods are made into nails.

The metal rods move along slowly, and a blade forms the nail points.

These blades are changed every 600 hours.

This machine forms nailheads by flattening them with great pressure on the rod ends.

Nailheads are formed at a rate of 1,400 per minute.

The manufacturing of nails is now finished.

They fall into a chute, then into this collecting bin.

Nails are sold by the pound or embedded in plastic rolls, as we see here.

This machine inserts 167 nails into each roll.

The plastic strip has teeth, and the nails hook into these.

They handle the rolls with gloves, since the coating applied to the nails is not yet dry.

This machine produces five rolls a minute for a total of 835 nails.

Making spiral nails requires an extra processing step.

This machine puts the spirals into the nails with these cylinders and welds them.

It makes 1,200 nails a minute.

Then the nails are put together into strips for use in pneumatic nailing guns.

Each strip contains 30 spiral nails.

To help them in place, the nails are coated with a resin that dries in four minutes.

This is the nailing device that uses nails on a strip.

It sets the nails in one strike with the user's trigger finger.

Now we move on to the fabrication of staples.

The staple press binds 80 iron wires, which have been well-lined up.

The 80 small wires are placed side by side.

The wires are glued together.

Then the wires come out well-adhered to one another.

The staple strips are fed into this machine.

It cuts the staples to the desired length and folds them in one stroke of this press, which applies 40 tons of pressure.

Staples are formed on this gauge, and the staple strips are then ready for packaging.

Every day they produce a total of some 25 million nails here, which require the processing of 11,000 tons of metal annually.

At work and at play, our precious vision can be at risk.

For instance, we need to protect our eyes when we're using power tools and when we're playing squash.

Thankfully, all we need to do is wear safety glasses.

How do they make them so resistant?

Let's have a look.

Many sports and trades require the wearing of safety glasses.

These glasses are made with plastic molding.

Here we see the interior of a mold.

The optical part of the lens is mirrored in order to be as transparent as possible without being deformed.

The glasses are made by melting the primary material, a plastic resin called polycarbonate.

The resin granules are poured into this machine.

It becomes liquefied at a temperature of 450 degrees.

The liquid plastic is injected into the mold under pressure over a 30- to 60-second period.

The plastic hardens rapidly, and the glasses are then removed from the mold.

They mold several glasses at a time.

The glasses are separated by hand and then are given an initial visual inspection.

The glasses are placed on this support.

They're then taken to the laboratory, where they'll be given a surface treatment.

But before beginning the treatment, they're washed to eliminate any impurities and to assure that the coating treatment adheres well to the lens.

When they've been washed, the glasses are then rinsed in clear water.

The glasses are now gently soaked in a chemical solution, which prevents misting and scratching of the lens.

This coating now has to be cooked.

They direct the glasses toward an oven heated to 480 degrees.

The soaking and cooking processes vary between 30 minutes and 2 hours.

Each pair of glasses is inspected to make sure there are no imperfections or distortions in the lenses.

Then the glasses are placed on this support.

This milling machine automatically removes the last piece of polycarbonate.

This one was left in place so that they would be able to handle the glasses without having to touch the lenses.

At this stage of the production of the glasses, the nosepiece is glued on.

Certain pairs of glasses are selected from each production run.

Here they evaluate the resistance of glasses to a racquetball hurled at them at 90 miles per hour.

Here a hockey visor is tested against a puck traveling at 60 miles an hour.

To conform to safety standards, the glasses must withstand these tests.

It confirms that they're truly safe.

They now proceed to final assembly steps in making the glasses.

The last few pieces of the glasses, such as the plastic ear stems, are installed.

Now completed, the glasses are placed in cases.

It's the final step in their fabrication.

They make several types of safety glasses here-- industrial, hockey and football visors, swimming goggles, and racquetball glasses.

This facility turns out thousands of safety glasses every day, and the polycarbonate resin used to make those safety glasses could very well save your eyes one day.

Early man relied on animal skins to protect himself against the elements.

Eventually, fabrics were invented, giving us a bit more choice in the matter and eliminating the need to hunt or go naked.

Today textile mills make fabrics in every conceivable pattern and color.

Fabric is made from thousands of braided threads.

This mill has 700 bobbins of polyester.

Each bobbin contains 155 miles of thread.

We begin by separating the threads.

This warp unit takes the 700 strands and assembles them.

Then this comb separates them.

Other strands are added, and in total there will be 7,000 of them.

One fabric is composed of threads braided at 90 degrees.

The warp threads are assembled lengthwise, while the weft threads are joined transversely.

To prevent the threads from tearing, they pass through a bin of glue.

These rollers eliminate the surplus.

The glue will be removed with water before dyeing the threads.

The glued-together threads exit this machine.

These large green cylinders are heated and dry the glue on the threads.

Knitting will soon begin.

The 700 strands are newly separated on this loom roller.

Each thread must pass through a blade to produce a specific design.

This machine takes the 7,000 strands of thread, one by one, and they pass through the blade.

It's a highly precise operation.

The threads pass through a blade, and the weaving finally begins.

On this jacquard-type loom roller, the warped thread is inserted by a jet of air.

The weaving machine assembles two loom rollers made of 7,000 strands.

The fabric reaches a width of 12 feet.

The dark threads are inserted into the weave.

They insert 600 weft strands per minute.

The blades remove the weft strands to insert the warp ones between the two.

A comb pushes the weft.

The plate of the breakage chain stops the machine if a thread should break.

This bobbin contains 155 miles of thread.

The weft thread is in the insertion nozzle.

When a weft is inserted, an air jet nudges it in.

The loom roller operates at full tilt.

It makes 600 thread intersections a minute.

Weaving is now over.

We move on to the following steps-- washing and dyeing.

Washing is done in a soapy solution at 175 degrees and at a speed of 195 feet of fabric a minute.

The fabric is rinsed in clear water of about 85 degrees.

Now it's on to dyeing.

This is done with jets.

Up to 7 1/2 miles of fabric is placed in clean water into which colorants have been added.

The solution is heated, and the fabric soaks here for about six hours.

Then it will be rinsed in lukewarm water.

The fabric is placed in a bin.

This machine is called an opener.

It unfolds and stretches the material before rolling it up on an immense roller.

And now the roll is almost full.

We now move to thermosetting in a high-temperature oven that dries the fabric.

The temperature is almost 400 degrees at the oven's entrance.

The fabric circulates here for 45 seconds.

The bobbin that we saw at the beginning has produced 15 miles of fabric.

This finished roll weighs 3,300 pounds.

Bicycles have come a long way from the original basic design.

Now they feature multiple gears, high-tech materials like carbon-fiber frames and featherlight metal alloys.

And they're made to tackle everything from quiet bike paths to the most rugged mountain trails.

A french invention of 1790, the first bicycle resembled a 2-wheeled wooden horse without pedals or handlebars.

In 1817, a german gave it direction control.

The addition of pedals to the front wheels came from france in 1861.

The british contributed as well, adding the large front wheel in 1870.

By 1903, all countries participated in the first bicycle tour de france.

A bicycle is a beautiful piece of engineering.

The frames are made of steel or a chromium-molybdenum alloy known as chromoly.

Fabrication begins with these hollow tubes.

The tube cutter cuts the steel before sending it to the bender.

The bender curves the tubes cold, exerting strong pressure against the bending jig.

The tubes must now be machined-- that is, cut into lengths so that they correctly fit into one another.

During this operation, cutting oil cools the tube.

The tube is cut, taking into consideration the insertion angle of the other pieces.

Tubes to be welded together are placed in this support.

They insert a piece in an alloy of silver and bronze, which increases the strength and produces a better finish at the welding point.

Welding now takes place.

Welding of the frame requires about two minutes at a temperature of over 1,400 degrees.

Once welded, the part takes four minutes to cool.

They proceed in the same way with all the tubes that form the frame of the bicycle.

At this stage, it's important to straighten the frame, which could have deformed during welding.

They verify the alignment of the tubes and straighten it out cold with a tool that sets it to the right dimensions.

Now they're going to paint the frames.

Paint is applied with a spray gun and adheres to the frame by static contact.

Then the paint will be baked in a natural-gas oven at 425 degrees for 15 minutes.

The frame is now cooled, and we can begin the assembly.

The labels are now applied.

In another department, an employee assembles the handlebars.

He installs the mechanism for the brakes and the gears.

Now we move on to the wheel rims.

The 36 stainless-steel spokes of each aluminum wheel are installed manually.

The dexterity of these workers allows them to install spokes on 65 wheel rims in an hour.

This spoke tool allows them to screw the spokes into the rim.

This machine exerts a pressure on the spokes so that they'll have the desired tension.

If there's too much or not enough tension, the rim will be crooked.

This machine aligns the rims, essential for proper functioning of the bicycle.

It automatically adjusts the spokes so that the wheel will be truly straight.

Next step-- placing of the tubes and the tires on the wheel rims.

Set upside down, the bicycle circulates from one workshop to another, where they will install the last mechanical parts.

These accessories are not made here.

The handlebars, the pedals, the fork, the brake, and chain mechanisms are all installed manually.

Here they screw on the rear brake plate.

Finally they inspect each bicycle to make sure that the bolts are well-tightened and that everything's working properly.

Then it's on to packaging.

This factory makes 2,500 bicycles each day.

Assembled from various tubes of chromoly, each one weighs about 25 pounds and will run for thousands of miles.