How It's Made (2001–…): Season 11, Episode 1 - Binoculars/Sparklers/Rubber Boots/Circular Saw Blades - full transcript
Narrator:
A PAIR OF BINOCULARS
IS ESSENTIALLY A HANDHELD
DOUBLE TELESCOPE.
LIGHT RAYS FROM THE OBJECT
YOU'RE VIEWING
ENTER THE LENSES ON THE FAR
END,
THE OBJECTIVES.
THIS PROJECTS AN IMAGE
JUST BEHIND THOSE LENSES
INSIDE THE BINOCULARS'
HOUSING.
THE SMALLER EYEPIECE LENSES
YOU PEER THROUGH
THEN MAGNIFY THAT IMAGE.
THE OBJECTIVES ARE CURVED,
CAUSING THE IMAGE TO APPEAR
UPSIDE DOWN.
THE TURN IT RIGHT SIDE UP,
EACH BINOCULAR HALF
NEEDS A GLASS PRISM.
USING U.V.-LIGHT-ACTIVATED
GLUE,
WORKERS MOUNT SEVERAL PRISMS
ON STEEL PLATES
THAT TAKE THEM THROUGH A
SERIES
OF GRINDING AND POLISHING
STEPS.
PROTECTIVE PAINT
PREVENTS ANY DUST
FROM CONTAMINATING
THE PRISTINE SURFACE.
GRINDING WITH DIAMOND DUST
REMOVES MERE TENTHS
OF A MILLIMETER OF GLASS.
POLISHING
WITH AN EVEN FINER ABRASIVE
REMOVES ANOTHER 1/100
OF A MILLIMETER.
AT THE END OF IT ALL, THE
THREE
SIDES ARE PERFECTLY FLAT.
THIS MINIMIZES REFLECTION,
CRITICAL FOR MAKING THE GLASS
SEE-THROUGH.
TO MAKE EACH PRISM,
THEY GLUE TWO PIECES OF GLASS
TOGETHER AT 90 DEGREES.
THIS SPECIAL MACHINE ENSURES
THE ANGLE IS PRECISE.
A SHOT OF U.V. LIGHT
DRIES THE GLUE.
THE FIRST PIECE OF GLASS
ROTATES
THE INVERTED IMAGE 90 DEGREES.
THE SECOND ROTATES IT ANOTHER
90 DEGREES, COMPLETING THE
FLIP.
NOW FOR THE OBJECTIVES.
THESE CURVED LENSES HAVE
UNDERGONE THE SAME GRINDING
AND POLISHING STEPS
AS THE PRISMS.
NOW THEY GO THROUGH A
NINE-STAGE
COMPUTER-GUIDED
CLEANING PROCESS.
AFTER INSPECTING THE LENSES,
A TECHNICIAN GLUES TWO
TOGETHER.
A DOUBLE LENS LIMITS A TYPE
OF DISTORTION
THAT CAUSES FRINGES OF COLOR
TO APPEAR AROUND THE IMAGE.
IT'S CRITICAL TO MATCH THEM
TO EACH OTHER PERFECTLY.
IF THE ALIGNMENT'S OFF
BY MORE THAN JUST 1/100th
OF A MILLIMETER,
THE IMAGE WILL BE POOR.
THIS ALIGNMENT MACHINE
DISPLAYS A DOT
REPRESENTING THE CENTER
OF EACH LENS,
SO IT'S JUST A MATTER
OF MATCHING THE DOTS.
A 2-SECOND SHOT OF U.V. LIGHT
DRIES THE GLUE.
NEXT, A TECHNICIAN LOADS
MINERAL
PELLETS INTO A VACUUM CHAMBER.
THEIR EXACT FORMULATION
IS A COMPANY SECRET.
THE PELLETS PRODUCE
AN ANTI-REFLECTION LENS
COATING
THAT LETS MORE LIGHT
COME THROUGH THE LENSES.
INSIDE THE VACUUM CHAMBER,
A BEAM OF ELECTRONS
EVAPORATES THE PELLETS
INTO MICROSCOPIC PARTICLES
THAT COAT THE LENSES.
IT'S TIME TO BEGIN ASSEMBLING
THE BINOCULARS.
FIRST, THE OBJECTIVES
GO INTO THE HOUSING,
WHICH IS USUALLY MADE OF
PLASTIC, ALUMINUM, OR CARBON.
WORKERS CLEAN THE LENSES
WITH A FEW BLASTS
OF COMPRESSED NITROGEN...
...THEN SECURE THEM IN PLACE
WITH THREADED HOLDING RINGS.
NOW A FEW DROPS OF GLUE
BEHIND THE OBJECTIVES,
WHERE THE PRISMS WILL GO,
ANOTHER BLAST OF NITROGEN
TO REMOVE ANY DUST,
THEN THEY INSERT THE PRISMS.
THIS OPTICAL MACHINE ALIGNS
THE FOCAL POINTS OF THE PRISM
AND ITS CORRESPONDING
OBJECTIVE.
THEN, SOME MORE GLUE
TO LOCK IN THE POSITIONING
AND A BLAST OF U.V. LIGHT
TO DRY THE GLUE.
NOW THEY SILICONE THE
OBJECTIVES
AND PRISMS
TO THE HOUSING'S MIDDLE
SECTION.
SILICONE CREATES AN AIRTIGHT
AND WATERPROOF SEAL.
THIS HOLDING MECHANISM
PRESSES THE PARTS TOGETHER
WHILE WORKERS
DRIVE IN THE SCREWS.
ONTO THE OPPOSITE END OF THE
MIDDLE SECTION GO THE OCULARS,
THE SMALLER LENSES
THROUGH WHICH YOU LOOK.
THOSE ALSO ATTACH
WITH THREADED HOLDING RINGS.
NOW, THROUGH A VALVE
ON EACH SIDE,
A MACHINE SUCKS AIR
FROM THE HOUSING
AND INJECTS NITROGEN GAS.
NITROGEN PREVENTS THE LENSES
FROM FOGGING UP.
A DAY AFTER FILLING,
THEY RECHECK
THE NITROGEN PRESSURE
TO MAKE SURE THERE'S NO LEAK.
THIS FACTORY PUTS ALL
THE BINOCULARS IT PRODUCES
THROUGH RIGOROUS TESTING,
SUBJECTING THEM
TO PROLONGED VIBRATION,
WATER PRESSURE, EXTREME HEAT,
FREEZING TEMPERATURES,
AND OTHER TRYING CONDITIONS.
AFTER EVERY TEST,
INSPECTORS MAKE SURE
EVERYTHING
STILL WORKS PERFECTLY,
BOTH MECHANICALLY AND
OPTICALLY.
Narrator: SPARKLERS HAVE
SIZZLED
ON THE PARTY SCENE FOR
DECADES,
ADDING PYROTECHNICAL GLITTER
TO WEDDINGS
AND BIRTHDAY CELEBRATIONS.
THEY EVOLVED FROM MORE
TRADITIONAL FIREWORKS
AND ARE THE ONLY KIND THAT THE
CONSUMER CAN HANDLE WHEN LIT.
LIGHTING ONE DEFINITELY MEANS
EXCITEMENT IS IN THE AIR.
THE SPLASH OF FLASH CAN LAST
A MINUTE OR MORE,
DEPENDING ON THE LENGTH
OF THE SPARKLER.
THEY START WITH STEEL WIRES
THAT ARE ABOUT 19 INCHES LONG.
THEY LOAD BUNDLES OF THEM
INTO SLOTS OF A SORTING
MACHINE.
THE MACHINE VIBRATES,
AND THE WIRES FALL IN SINGLE
FILE INTO SMALLER OPENINGS.
THE OPERATOR THEN MOVES
A SPRING-LOADED WOODEN RACK
INTO POSITION.
IT OPENS LIKE THE BELLOWS
OF AN ACCORDION.
THE OPERATOR ROCKS
THE SORTING MACHINE OVERHEAD,
AND THE WIRES DROP
INTO THE SLITS OF THE RACK,
PERFECTLY ALIGNED.
AFTER 300 SPARKLER WIRES
HAVE FALLEN INTO POSITION,
THE OPERATOR PULLS A HANDLE
TO CLOSE THE RACK.
NOW, CLAMPED IN
THE ACCORDION-STYLE RACK,
THE WIRES ARE READY TO MOVE ON
TO THE NEXT STATION.
WIRES FOR PARADE SPARKLERS
ARE MUCH LONGER --
36 INCHES, IN FACT --
WHICH MEANS THEY'RE HEAVIER
THAN ORDINARY SPARKLERS.
THE OPERATOR LOADS EACH OF
THESE
WIRES MANUALLY INTO A RACK
THAT'S LARGER AND STURDIER
THAN THE LAST ONE.
THIS SYSTEM OF LOADING
IS A LOT MORE TIME-CONSUMING,
BUT PARADE SPARKLERS ARE WORTH
THE EXTRA TROUBLE
BECAUSE THEY'LL HAVE
A LONGER BURN TIME --
UP TO FOUR MINUTES.
NEXT, AN OPERATOR LOADS
BORIC ACID AND BARIUM NITRATE
INTO A BIG MIXING TANK.
THE BARIUM NITRATE
IS AN OXIDIZER
AND WILL HELP THE SPARKLER
BURN.
THE BORIC ACID IS A
NEUTRALIZER.
HE ADDS WATER
AND MIXES IN CORNSTARCH.
IT WILL BIND
ALL THE INGREDIENTS TOGETHER.
NEXT, HE POURS IN
SOME VERY FINE IRON FILINGS.
THESE BITS OF IRON WILL GIVE
THE SPARKLERS THEIR GOLD
COLOR.
THE OPERATOR THEN SUITS UP
IN PROTECTIVE GEAR
AND CLOSES THE DOOR.
HE'S THE ONLY ONE ALLOWED
INSIDE
TO LOAD THE SPARKLERS'
MOST VOLATILE INGREDIENT --
ALUMINUM POWDER.
ONCE MIXED INTO THE WET
SLURRY,
THE POWDER
IS VIRTUALLY HARMLESS,
AND THEY DON'T NEED TO TAKE
AS MANY SAFETY PRECAUTIONS.
CHAIN CONVEYORS NOW MOVE
THE RACK OF SPARKLER WIRES
INTO POSITION.
AN ELEVATOR LIFTS UP A TANK
OF THE SPARKLER SLURRY
TO DIP THE WIRES IN IT.
THE NEXT RACK OF WIRES
THEN MOVES FORWARD FOR
DIPPING.
286 RACKS OF WIRES MOVE
THROUGH THIS DIPPING STATION
EVERY HOUR AND 45 MINUTES.
THEY GO THROUGH A SECOND
DIPPING
STATION FOR ONE MORE COATING.
THE TWO COATINGS DOUBLE
THE DIAMETER OF THE WIRES.
AFTER EACH DIP,
WIRES RIDE AN OVERHEAD RAIL
THROUGH AN OVEN
TO BAKE THE SPARKLER SLURRY
UNTIL IT'S HARD.
AN INSPECTOR THEN EXAMINES
EACH SPARKLER.
SHE CHECKS FOR CRACKS
AND DEFECTS.
ANY WIRE THAT'S FLAWED
WILL BE REJECTED
BECAUSE THESE SPARKLERS HAVE
TO OUTSHINE THE COMPETITION.
IT TAKES HER ABOUT THREE
MINUTES
TO EXAMINE THE 300 SPARKLERS
ON A RACK.
THEY CHECK THE DIAMETER
OF EACH SPARKLER
BY SLIDING IT
THROUGH A TEMPLATE,
AND THEY BEND IT
TO CHECK ITS INTEGRITY.
THE SPARKLERS HAVE BEEN STORED
FOR A WEEK PRIOR TO PACKAGING
TO ALLOW THEM TO CURE.
AND NOW THEY'RE READY
FOR A PARTY,
AND THEY'RE SURE TO BE
THE CENTER OF ATTENTION.
Narrator: WELLINGTON BOOTS,
BILLY BOOTS, GALOSHES.
BY ANY NAME,
RUBBER RAIN BOOTS
OWE THEIR EXISTENCE
TO A 19th-CENTURY AMERICAN,
CHARLES GOODYEAR.
HE INVENTED
THE VULCANIZATION PROCESS,
A WAY OF KEEPING NATURAL
RUBBER
FROM DETERIORATING.
NOWADAYS, RAIN BOOTS ARE MADE
FROM A SYNTHETIC MATERIAL
CALLED THERMOPLASTIC RUBBER,
OR TPR.
THEY'RE FUNCTIONAL --
EVEN FASHIONABLE.
MAKING RUBBER BOOTS BEGINS
WITH SPOOLS OF POLYESTER YARN
FOR THEIR LINING.
A COLORED SPOOL ADDS
A THIN LINE OF COLOR
TO INDICATE THE FOOT SIZE
OF THE LINING.
A COMPUTER-PROGRAMMED MACHINE
CROCHETS THE YARN
WITH 242 NEEDLES.
AS WE CAN SEE IN SLOW MOTION,
EACH GATE OPENS COMPLETELY,
THEN CLOSES ON THE YARN.
THE NEEDLES ROTATE
750 TIMES PER SECOND.
THEY CAN PROGRAM THE MACHINE
TO MAKE LININGS
FOR ANY SIZE OF BOOT.
FOR QUALITY CONTROL,
WORKERS SPOT-CHECK A FEW
LININGS
FROM EVERY BATCH.
NOW THE ACTION MOVES
TO THIS AUTOMATED
INJECTION-MOLDING MACHINE
WITH SIX STATIONS.
EACH ONE PRODUCES
A PAIR OF BOOTS.
WORKERS CAREFULLY ROLL A PAIR
OF LININGS
ONTO EACH STATION'S FOOT FORM,
CALLED THE LAST.
THESE LASTS WILL CREATE
THE SPACE INSIDE THE BOOT
FOR THE LOWER LEG AND FOOT.
A FIVE-PART BOOT MOLD
CLOSES AROUND THE FOOT LAST.
THEN, A HIGH-PRESSURE
INJECTION SCREW
PUSHES IN MELTED
SYNTHETIC RUBBER,
FIRST IN THE SOLES,
THEN IN THE UPPER BOOT.
THE COMPANY LAB
REGULARLY TESTS SAMPLES
OF THE SYNTHETIC RUBBER
PELLETS
THAT FEED THE INJECTION
MACHINE
TO MAKE SURE THEY MELT
AND FLOW WELL.
THE LAB TECHNICIAN POURS IN
SOME PELLETS, MELTS THEM,
THEN PUSHES IN A PISTON
TO EXTRUDE THE MOLTEN RUBBER.
THE MACHINE MEASURES WHAT'S
CALLED THE MELT FLOW INDEX.
BACK ON THE FACTORY FLOOR,
A LARGE SUCTION HOSE
FEEDS RUBBER PELLETS
TO THE INJECTORS --
BLACK FOR THE BOOT BODY,
RED FOR THE SOLES.
AND AT THIS FACTORY,
NOTHING GOES TO WASTE.
IT RECYCLES RUBBER LEFTOVERS
OR REJECTS OF ALL COLORS
INTO A BATCH OF BLACK RUBBER.
THE SUCTION HOSE THEN
SENDS THE PELLETS INTO A
HOPPER
WHICH FEEDS THE BARREL
OF THE INJECTION UNIT.
THE HEATER BANDS
INSIDE THE BARRELS
MELT THE PELLETS
AT 200 DEGREES CELSIUS.
THEN, AT THE PRECISE MOMENT
THE MOLD ARRIVES,
THE INJECTOR SHOOTS
IN THE MOLTEN RUBBER.
GIANT CLAMPS APPLY PRESSURE
FOR ABOUT 10 SECONDS,
THEN RELEASE.
A HYDRAULIC CYLINDER
PUSHES UP THE LAST,
HELPING TO EXTRACT THE BOOTS.
THEN IT'S QUICKLY ON WITH NEW
LININGS FOR THE NEXT PAIR.
TOTAL MOLDING TIME?
JUST 30 SECONDS.
THE BOOTS COOL FOR 45 MINUTES,
THEN HEAD OFF TO PACKAGING...
MAKING JUST ONE STOP
ALONG THE WAY
AT THE PAD PRINTING MACHINE
TO GET THE COMPANY'S LOGO.
ELSEWHERE IN THE FACTORY,
A SEAMSTRESS
CAREFULLY CONSTRUCTS
A PATTERNED BOOT LINING.
THE FACTORY CROCHETS WHITE
LININGS IN A CONTINUOUS ROLL,
THEN HAS ANOTHER COMPANY
PRINT ON THE DESIGN.
THE TRICKIEST PART
IS SHAPING THE TOE
BECAUSE SHE HAS TO CURVE AND
CUT
THE MATERIAL AT THE SAME TIME.
FOR THESE PATTERNED BOOTS,
THE MACHINE INJECTS
A TRANSPARENT SYNTHETIC RUBBER
INTO THE MOLD
SO THAT THE PRINTED LINING
WILL SHOW THROUGH.
THE MIRROR-FINISH SURFACE
OF THE MOLD CAVITY
PRODUCES A HIGH-GLOSS BOOT.
THE PRINTED BOOT REQUIRES MORE
WORK AND COSTLIER MATERIALS
AND IS THEREFORE MORE
EXPENSIVE.
AFTER THE MOLDING, FOR
EXAMPLE,
IT HAS TO GO
TO THE TRIMMING STATION.
THERE, A WORKER SHAVES OFF
EXCESS MATERIAL
FROM THE TOP OF THE BOOT.
THEN HE SEWS ON A FABRIC
BINDING
TO SANDWICH THE LINING.
THE FACTORY RANDOMLY SELECTS
A BOOT FROM EACH BATCH
AND PUTS IT THROUGH A BATTERY
OF TESTS ON THIS FLEX MACHINE.
IT BENDS THE BOOT IN VARIOUS
WAYS SOME 300,000 TIMES,
ENSURING THAT THESE RAIN BOOTS
CAN WALK THE WALK.
Narrator: WHEN A CONSTRUCTION
SITE IS BUZZING WITH ACTIVITY,
IT'S USUALLY THE SOUND
OF THE CIRCULAR SAW.
ITS SPINNING TEETH CAN TAKE A
BITE OUT OF ANY JOB IN
SECONDS.
THERE ARE MANY CLAIMS
TO THE INVENTION
OF THE CIRCULAR SAW,
BUT THERE'S NO DOUBT THAT
WHEN ITS DESIGN WAS PERFECTED
IN THE LAST CENTURY,
IT REVOLUTIONIZED WOODWORKING.
WITH A CIRCULAR SAW,
YOU CAN GIVE ODD JOBS A WHIRL,
AND WHEN THE SAWDUST SETTLES,
YOU MAY HAVE DISCOVERED
YOUR INNER HANDYMAN.
TO MAKE A CIRCULAR-SAW BLADE,
A LASER BURNS
INTO A SHEET OF STEEL
TO CUT OUT JAGGED DISKS
IN THE BASIC SHAPE
OF A CIRCULAR-SAW BLADE.
THEY FEED EACH DISK TO ROLLERS
THAT PRESS GROOVES
ONTO BOTH SIDES.
THESE GROOVES
ARE TENSIONING RINGS
THAT WILL KEEP THE BLADE
FROM VIBRATING WHILE CUTTING.
WITHOUT THESE GROOVES,
THE CIRCULAR BLADE
WOULDN'T CUT STRAIGHT.
AT THE NEXT STATION,
THE ASSEMBLER MEASURES SAGS
AND BUCKLES
BEFORE FEEDING THE DISKS
TO A MACHINE
THAT ROLLS THEM FLAT
LIKE A PIE CRUST.
A GRINDING WHEEL
POLISHES THE BLADE.
AND THEN THEY LOAD BARRELS
OF THE DISKS INTO AN OVEN
TO BAKE UNTIL THEY'RE VERY
HARD.
THIS WILL TAKE ABOUT 24 HOURS.
MEANWHILE, CARBIDE TIPS
FOR THE BLADES' TEETH
FUNNEL PAST A LASER
THAT CONFIRMS
THEY'RE PROPERLY POSITIONED
FOR THE NEXT STEP.
A ROBOT THEN PICKS UP
ONE TIP AT A TIME
AND DELIVERS IT TO NOZZLES.
THE NOZZLES PUMP A PASTE
CALLED FLUX ONTO IT.
ANOTHER ROBOT PLACES A PIECE
OF SOLDER METAL ON THE FLUX.
THE NEXT ROBOT DELIVERS THE
TIPS
TO THE SAW-BLADE BODY.
ELEMENTS MELT THE SOLDER METAL
AND FLUX
TO FUSE THE CARBIDE TIPS
TO THE TEETH.
IT'S A TECHNIQUE CALLED
BRAZING.
TEETH WITH CARBIDE TIPS
LAST LONGER
WITHOUT LOSING THEIR
SHARPNESS.
CIRCULAR BLADES FOR SAWMILLS
HAVE A LARGER
AND DIFFERENT DESIGN.
THEY BRUSH FLUX
AROUND A SIDE HOLE
AND THEN PLACE SOLDERING METAL
ON AN ELONGATED CARBIDE TOOTH.
THEY BRAZE THE TOOTH
TO THE FLUX-COATED HOLE
AND INSTALL SEVERAL MORE
OF THESE CARBIDE SIDE TEETH.
THE SIDE TEETH WILL ENABLE
THIS SAWMILL BLADE
TO TEAR THROUGH BIG LOGS.
THE SMALLER CIRCULAR-SAW BLADE
NOW SPINS ON AN AXLE
WHILE A SPRAY NOZZLE
SANDBLASTS IT.
THE SANDBLASTING
CLEANS THE SURFACE
AND GIVES THE BLADE
A BRUSHED TEXTURE.
A MECHANICAL FINGER NOW MOVES
ONE OF THE BLADE'S TEETH
INTO POSITION FOR SHARPENING.
A GRINDING WHEEL
TAPERS EACH TOOTH.
A DIFFERENT WHEEL MOVES IN
AND GRINDS THE OUTSIDE
DIAMETER
OF THE BLADE.
THE GEOMETRIC ANGLE
OF THE GRINDING CAN VARY,
DEPENDING ON THE TYPE OF BLADE
BEING MADE.
THE GRINDING WHEEL THEN HONES
THE FACE OF EACH TOOTH
TO GIVE IT A SHARPER EDGE.
NEXT, A STRAIGHTENING
SPECIALIST
POUNDS OUT ANY REMAINING BUMPS
IN THE BLADE...
...AND DOUBLE-CHECKS IT
WITH A STRAIGHTEDGE TOOL.
HE WIPES OFF ANY SMUDGES
AND THEN HOLDS THE BLADE
TO THE LIGHT
AND EXAMINES IT TO CONFIRM
THAT IT HAS NO FLAWS.
A LASER THEN ETCHES THE
COMPANY
INSIGNIA ONTO THE BLADE.
AND NOW THE CIRCULAR-SAW BLADE
IS READY FOR ITS CLOSE-UP.
A CAMERA FOCUSES ON THE TEETH
AND SENDS THE PICTURE
TO A COMPUTER.
IT ANALYZES THE CUTTING ANGLE
AND THE CLEARANCE OF EACH
TOOTH
TO MAKE SURE
EACH ONE MEASURES UP.
THE RESULT
IS CIRCULAR-SAW BLADES
THAT SHOULD BE ABLE TO KEEP
THEIR EDGE ON THE JOB.
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A PAIR OF BINOCULARS
IS ESSENTIALLY A HANDHELD
DOUBLE TELESCOPE.
LIGHT RAYS FROM THE OBJECT
YOU'RE VIEWING
ENTER THE LENSES ON THE FAR
END,
THE OBJECTIVES.
THIS PROJECTS AN IMAGE
JUST BEHIND THOSE LENSES
INSIDE THE BINOCULARS'
HOUSING.
THE SMALLER EYEPIECE LENSES
YOU PEER THROUGH
THEN MAGNIFY THAT IMAGE.
THE OBJECTIVES ARE CURVED,
CAUSING THE IMAGE TO APPEAR
UPSIDE DOWN.
THE TURN IT RIGHT SIDE UP,
EACH BINOCULAR HALF
NEEDS A GLASS PRISM.
USING U.V.-LIGHT-ACTIVATED
GLUE,
WORKERS MOUNT SEVERAL PRISMS
ON STEEL PLATES
THAT TAKE THEM THROUGH A
SERIES
OF GRINDING AND POLISHING
STEPS.
PROTECTIVE PAINT
PREVENTS ANY DUST
FROM CONTAMINATING
THE PRISTINE SURFACE.
GRINDING WITH DIAMOND DUST
REMOVES MERE TENTHS
OF A MILLIMETER OF GLASS.
POLISHING
WITH AN EVEN FINER ABRASIVE
REMOVES ANOTHER 1/100
OF A MILLIMETER.
AT THE END OF IT ALL, THE
THREE
SIDES ARE PERFECTLY FLAT.
THIS MINIMIZES REFLECTION,
CRITICAL FOR MAKING THE GLASS
SEE-THROUGH.
TO MAKE EACH PRISM,
THEY GLUE TWO PIECES OF GLASS
TOGETHER AT 90 DEGREES.
THIS SPECIAL MACHINE ENSURES
THE ANGLE IS PRECISE.
A SHOT OF U.V. LIGHT
DRIES THE GLUE.
THE FIRST PIECE OF GLASS
ROTATES
THE INVERTED IMAGE 90 DEGREES.
THE SECOND ROTATES IT ANOTHER
90 DEGREES, COMPLETING THE
FLIP.
NOW FOR THE OBJECTIVES.
THESE CURVED LENSES HAVE
UNDERGONE THE SAME GRINDING
AND POLISHING STEPS
AS THE PRISMS.
NOW THEY GO THROUGH A
NINE-STAGE
COMPUTER-GUIDED
CLEANING PROCESS.
AFTER INSPECTING THE LENSES,
A TECHNICIAN GLUES TWO
TOGETHER.
A DOUBLE LENS LIMITS A TYPE
OF DISTORTION
THAT CAUSES FRINGES OF COLOR
TO APPEAR AROUND THE IMAGE.
IT'S CRITICAL TO MATCH THEM
TO EACH OTHER PERFECTLY.
IF THE ALIGNMENT'S OFF
BY MORE THAN JUST 1/100th
OF A MILLIMETER,
THE IMAGE WILL BE POOR.
THIS ALIGNMENT MACHINE
DISPLAYS A DOT
REPRESENTING THE CENTER
OF EACH LENS,
SO IT'S JUST A MATTER
OF MATCHING THE DOTS.
A 2-SECOND SHOT OF U.V. LIGHT
DRIES THE GLUE.
NEXT, A TECHNICIAN LOADS
MINERAL
PELLETS INTO A VACUUM CHAMBER.
THEIR EXACT FORMULATION
IS A COMPANY SECRET.
THE PELLETS PRODUCE
AN ANTI-REFLECTION LENS
COATING
THAT LETS MORE LIGHT
COME THROUGH THE LENSES.
INSIDE THE VACUUM CHAMBER,
A BEAM OF ELECTRONS
EVAPORATES THE PELLETS
INTO MICROSCOPIC PARTICLES
THAT COAT THE LENSES.
IT'S TIME TO BEGIN ASSEMBLING
THE BINOCULARS.
FIRST, THE OBJECTIVES
GO INTO THE HOUSING,
WHICH IS USUALLY MADE OF
PLASTIC, ALUMINUM, OR CARBON.
WORKERS CLEAN THE LENSES
WITH A FEW BLASTS
OF COMPRESSED NITROGEN...
...THEN SECURE THEM IN PLACE
WITH THREADED HOLDING RINGS.
NOW A FEW DROPS OF GLUE
BEHIND THE OBJECTIVES,
WHERE THE PRISMS WILL GO,
ANOTHER BLAST OF NITROGEN
TO REMOVE ANY DUST,
THEN THEY INSERT THE PRISMS.
THIS OPTICAL MACHINE ALIGNS
THE FOCAL POINTS OF THE PRISM
AND ITS CORRESPONDING
OBJECTIVE.
THEN, SOME MORE GLUE
TO LOCK IN THE POSITIONING
AND A BLAST OF U.V. LIGHT
TO DRY THE GLUE.
NOW THEY SILICONE THE
OBJECTIVES
AND PRISMS
TO THE HOUSING'S MIDDLE
SECTION.
SILICONE CREATES AN AIRTIGHT
AND WATERPROOF SEAL.
THIS HOLDING MECHANISM
PRESSES THE PARTS TOGETHER
WHILE WORKERS
DRIVE IN THE SCREWS.
ONTO THE OPPOSITE END OF THE
MIDDLE SECTION GO THE OCULARS,
THE SMALLER LENSES
THROUGH WHICH YOU LOOK.
THOSE ALSO ATTACH
WITH THREADED HOLDING RINGS.
NOW, THROUGH A VALVE
ON EACH SIDE,
A MACHINE SUCKS AIR
FROM THE HOUSING
AND INJECTS NITROGEN GAS.
NITROGEN PREVENTS THE LENSES
FROM FOGGING UP.
A DAY AFTER FILLING,
THEY RECHECK
THE NITROGEN PRESSURE
TO MAKE SURE THERE'S NO LEAK.
THIS FACTORY PUTS ALL
THE BINOCULARS IT PRODUCES
THROUGH RIGOROUS TESTING,
SUBJECTING THEM
TO PROLONGED VIBRATION,
WATER PRESSURE, EXTREME HEAT,
FREEZING TEMPERATURES,
AND OTHER TRYING CONDITIONS.
AFTER EVERY TEST,
INSPECTORS MAKE SURE
EVERYTHING
STILL WORKS PERFECTLY,
BOTH MECHANICALLY AND
OPTICALLY.
Narrator: SPARKLERS HAVE
SIZZLED
ON THE PARTY SCENE FOR
DECADES,
ADDING PYROTECHNICAL GLITTER
TO WEDDINGS
AND BIRTHDAY CELEBRATIONS.
THEY EVOLVED FROM MORE
TRADITIONAL FIREWORKS
AND ARE THE ONLY KIND THAT THE
CONSUMER CAN HANDLE WHEN LIT.
LIGHTING ONE DEFINITELY MEANS
EXCITEMENT IS IN THE AIR.
THE SPLASH OF FLASH CAN LAST
A MINUTE OR MORE,
DEPENDING ON THE LENGTH
OF THE SPARKLER.
THEY START WITH STEEL WIRES
THAT ARE ABOUT 19 INCHES LONG.
THEY LOAD BUNDLES OF THEM
INTO SLOTS OF A SORTING
MACHINE.
THE MACHINE VIBRATES,
AND THE WIRES FALL IN SINGLE
FILE INTO SMALLER OPENINGS.
THE OPERATOR THEN MOVES
A SPRING-LOADED WOODEN RACK
INTO POSITION.
IT OPENS LIKE THE BELLOWS
OF AN ACCORDION.
THE OPERATOR ROCKS
THE SORTING MACHINE OVERHEAD,
AND THE WIRES DROP
INTO THE SLITS OF THE RACK,
PERFECTLY ALIGNED.
AFTER 300 SPARKLER WIRES
HAVE FALLEN INTO POSITION,
THE OPERATOR PULLS A HANDLE
TO CLOSE THE RACK.
NOW, CLAMPED IN
THE ACCORDION-STYLE RACK,
THE WIRES ARE READY TO MOVE ON
TO THE NEXT STATION.
WIRES FOR PARADE SPARKLERS
ARE MUCH LONGER --
36 INCHES, IN FACT --
WHICH MEANS THEY'RE HEAVIER
THAN ORDINARY SPARKLERS.
THE OPERATOR LOADS EACH OF
THESE
WIRES MANUALLY INTO A RACK
THAT'S LARGER AND STURDIER
THAN THE LAST ONE.
THIS SYSTEM OF LOADING
IS A LOT MORE TIME-CONSUMING,
BUT PARADE SPARKLERS ARE WORTH
THE EXTRA TROUBLE
BECAUSE THEY'LL HAVE
A LONGER BURN TIME --
UP TO FOUR MINUTES.
NEXT, AN OPERATOR LOADS
BORIC ACID AND BARIUM NITRATE
INTO A BIG MIXING TANK.
THE BARIUM NITRATE
IS AN OXIDIZER
AND WILL HELP THE SPARKLER
BURN.
THE BORIC ACID IS A
NEUTRALIZER.
HE ADDS WATER
AND MIXES IN CORNSTARCH.
IT WILL BIND
ALL THE INGREDIENTS TOGETHER.
NEXT, HE POURS IN
SOME VERY FINE IRON FILINGS.
THESE BITS OF IRON WILL GIVE
THE SPARKLERS THEIR GOLD
COLOR.
THE OPERATOR THEN SUITS UP
IN PROTECTIVE GEAR
AND CLOSES THE DOOR.
HE'S THE ONLY ONE ALLOWED
INSIDE
TO LOAD THE SPARKLERS'
MOST VOLATILE INGREDIENT --
ALUMINUM POWDER.
ONCE MIXED INTO THE WET
SLURRY,
THE POWDER
IS VIRTUALLY HARMLESS,
AND THEY DON'T NEED TO TAKE
AS MANY SAFETY PRECAUTIONS.
CHAIN CONVEYORS NOW MOVE
THE RACK OF SPARKLER WIRES
INTO POSITION.
AN ELEVATOR LIFTS UP A TANK
OF THE SPARKLER SLURRY
TO DIP THE WIRES IN IT.
THE NEXT RACK OF WIRES
THEN MOVES FORWARD FOR
DIPPING.
286 RACKS OF WIRES MOVE
THROUGH THIS DIPPING STATION
EVERY HOUR AND 45 MINUTES.
THEY GO THROUGH A SECOND
DIPPING
STATION FOR ONE MORE COATING.
THE TWO COATINGS DOUBLE
THE DIAMETER OF THE WIRES.
AFTER EACH DIP,
WIRES RIDE AN OVERHEAD RAIL
THROUGH AN OVEN
TO BAKE THE SPARKLER SLURRY
UNTIL IT'S HARD.
AN INSPECTOR THEN EXAMINES
EACH SPARKLER.
SHE CHECKS FOR CRACKS
AND DEFECTS.
ANY WIRE THAT'S FLAWED
WILL BE REJECTED
BECAUSE THESE SPARKLERS HAVE
TO OUTSHINE THE COMPETITION.
IT TAKES HER ABOUT THREE
MINUTES
TO EXAMINE THE 300 SPARKLERS
ON A RACK.
THEY CHECK THE DIAMETER
OF EACH SPARKLER
BY SLIDING IT
THROUGH A TEMPLATE,
AND THEY BEND IT
TO CHECK ITS INTEGRITY.
THE SPARKLERS HAVE BEEN STORED
FOR A WEEK PRIOR TO PACKAGING
TO ALLOW THEM TO CURE.
AND NOW THEY'RE READY
FOR A PARTY,
AND THEY'RE SURE TO BE
THE CENTER OF ATTENTION.
Narrator: WELLINGTON BOOTS,
BILLY BOOTS, GALOSHES.
BY ANY NAME,
RUBBER RAIN BOOTS
OWE THEIR EXISTENCE
TO A 19th-CENTURY AMERICAN,
CHARLES GOODYEAR.
HE INVENTED
THE VULCANIZATION PROCESS,
A WAY OF KEEPING NATURAL
RUBBER
FROM DETERIORATING.
NOWADAYS, RAIN BOOTS ARE MADE
FROM A SYNTHETIC MATERIAL
CALLED THERMOPLASTIC RUBBER,
OR TPR.
THEY'RE FUNCTIONAL --
EVEN FASHIONABLE.
MAKING RUBBER BOOTS BEGINS
WITH SPOOLS OF POLYESTER YARN
FOR THEIR LINING.
A COLORED SPOOL ADDS
A THIN LINE OF COLOR
TO INDICATE THE FOOT SIZE
OF THE LINING.
A COMPUTER-PROGRAMMED MACHINE
CROCHETS THE YARN
WITH 242 NEEDLES.
AS WE CAN SEE IN SLOW MOTION,
EACH GATE OPENS COMPLETELY,
THEN CLOSES ON THE YARN.
THE NEEDLES ROTATE
750 TIMES PER SECOND.
THEY CAN PROGRAM THE MACHINE
TO MAKE LININGS
FOR ANY SIZE OF BOOT.
FOR QUALITY CONTROL,
WORKERS SPOT-CHECK A FEW
LININGS
FROM EVERY BATCH.
NOW THE ACTION MOVES
TO THIS AUTOMATED
INJECTION-MOLDING MACHINE
WITH SIX STATIONS.
EACH ONE PRODUCES
A PAIR OF BOOTS.
WORKERS CAREFULLY ROLL A PAIR
OF LININGS
ONTO EACH STATION'S FOOT FORM,
CALLED THE LAST.
THESE LASTS WILL CREATE
THE SPACE INSIDE THE BOOT
FOR THE LOWER LEG AND FOOT.
A FIVE-PART BOOT MOLD
CLOSES AROUND THE FOOT LAST.
THEN, A HIGH-PRESSURE
INJECTION SCREW
PUSHES IN MELTED
SYNTHETIC RUBBER,
FIRST IN THE SOLES,
THEN IN THE UPPER BOOT.
THE COMPANY LAB
REGULARLY TESTS SAMPLES
OF THE SYNTHETIC RUBBER
PELLETS
THAT FEED THE INJECTION
MACHINE
TO MAKE SURE THEY MELT
AND FLOW WELL.
THE LAB TECHNICIAN POURS IN
SOME PELLETS, MELTS THEM,
THEN PUSHES IN A PISTON
TO EXTRUDE THE MOLTEN RUBBER.
THE MACHINE MEASURES WHAT'S
CALLED THE MELT FLOW INDEX.
BACK ON THE FACTORY FLOOR,
A LARGE SUCTION HOSE
FEEDS RUBBER PELLETS
TO THE INJECTORS --
BLACK FOR THE BOOT BODY,
RED FOR THE SOLES.
AND AT THIS FACTORY,
NOTHING GOES TO WASTE.
IT RECYCLES RUBBER LEFTOVERS
OR REJECTS OF ALL COLORS
INTO A BATCH OF BLACK RUBBER.
THE SUCTION HOSE THEN
SENDS THE PELLETS INTO A
HOPPER
WHICH FEEDS THE BARREL
OF THE INJECTION UNIT.
THE HEATER BANDS
INSIDE THE BARRELS
MELT THE PELLETS
AT 200 DEGREES CELSIUS.
THEN, AT THE PRECISE MOMENT
THE MOLD ARRIVES,
THE INJECTOR SHOOTS
IN THE MOLTEN RUBBER.
GIANT CLAMPS APPLY PRESSURE
FOR ABOUT 10 SECONDS,
THEN RELEASE.
A HYDRAULIC CYLINDER
PUSHES UP THE LAST,
HELPING TO EXTRACT THE BOOTS.
THEN IT'S QUICKLY ON WITH NEW
LININGS FOR THE NEXT PAIR.
TOTAL MOLDING TIME?
JUST 30 SECONDS.
THE BOOTS COOL FOR 45 MINUTES,
THEN HEAD OFF TO PACKAGING...
MAKING JUST ONE STOP
ALONG THE WAY
AT THE PAD PRINTING MACHINE
TO GET THE COMPANY'S LOGO.
ELSEWHERE IN THE FACTORY,
A SEAMSTRESS
CAREFULLY CONSTRUCTS
A PATTERNED BOOT LINING.
THE FACTORY CROCHETS WHITE
LININGS IN A CONTINUOUS ROLL,
THEN HAS ANOTHER COMPANY
PRINT ON THE DESIGN.
THE TRICKIEST PART
IS SHAPING THE TOE
BECAUSE SHE HAS TO CURVE AND
CUT
THE MATERIAL AT THE SAME TIME.
FOR THESE PATTERNED BOOTS,
THE MACHINE INJECTS
A TRANSPARENT SYNTHETIC RUBBER
INTO THE MOLD
SO THAT THE PRINTED LINING
WILL SHOW THROUGH.
THE MIRROR-FINISH SURFACE
OF THE MOLD CAVITY
PRODUCES A HIGH-GLOSS BOOT.
THE PRINTED BOOT REQUIRES MORE
WORK AND COSTLIER MATERIALS
AND IS THEREFORE MORE
EXPENSIVE.
AFTER THE MOLDING, FOR
EXAMPLE,
IT HAS TO GO
TO THE TRIMMING STATION.
THERE, A WORKER SHAVES OFF
EXCESS MATERIAL
FROM THE TOP OF THE BOOT.
THEN HE SEWS ON A FABRIC
BINDING
TO SANDWICH THE LINING.
THE FACTORY RANDOMLY SELECTS
A BOOT FROM EACH BATCH
AND PUTS IT THROUGH A BATTERY
OF TESTS ON THIS FLEX MACHINE.
IT BENDS THE BOOT IN VARIOUS
WAYS SOME 300,000 TIMES,
ENSURING THAT THESE RAIN BOOTS
CAN WALK THE WALK.
Narrator: WHEN A CONSTRUCTION
SITE IS BUZZING WITH ACTIVITY,
IT'S USUALLY THE SOUND
OF THE CIRCULAR SAW.
ITS SPINNING TEETH CAN TAKE A
BITE OUT OF ANY JOB IN
SECONDS.
THERE ARE MANY CLAIMS
TO THE INVENTION
OF THE CIRCULAR SAW,
BUT THERE'S NO DOUBT THAT
WHEN ITS DESIGN WAS PERFECTED
IN THE LAST CENTURY,
IT REVOLUTIONIZED WOODWORKING.
WITH A CIRCULAR SAW,
YOU CAN GIVE ODD JOBS A WHIRL,
AND WHEN THE SAWDUST SETTLES,
YOU MAY HAVE DISCOVERED
YOUR INNER HANDYMAN.
TO MAKE A CIRCULAR-SAW BLADE,
A LASER BURNS
INTO A SHEET OF STEEL
TO CUT OUT JAGGED DISKS
IN THE BASIC SHAPE
OF A CIRCULAR-SAW BLADE.
THEY FEED EACH DISK TO ROLLERS
THAT PRESS GROOVES
ONTO BOTH SIDES.
THESE GROOVES
ARE TENSIONING RINGS
THAT WILL KEEP THE BLADE
FROM VIBRATING WHILE CUTTING.
WITHOUT THESE GROOVES,
THE CIRCULAR BLADE
WOULDN'T CUT STRAIGHT.
AT THE NEXT STATION,
THE ASSEMBLER MEASURES SAGS
AND BUCKLES
BEFORE FEEDING THE DISKS
TO A MACHINE
THAT ROLLS THEM FLAT
LIKE A PIE CRUST.
A GRINDING WHEEL
POLISHES THE BLADE.
AND THEN THEY LOAD BARRELS
OF THE DISKS INTO AN OVEN
TO BAKE UNTIL THEY'RE VERY
HARD.
THIS WILL TAKE ABOUT 24 HOURS.
MEANWHILE, CARBIDE TIPS
FOR THE BLADES' TEETH
FUNNEL PAST A LASER
THAT CONFIRMS
THEY'RE PROPERLY POSITIONED
FOR THE NEXT STEP.
A ROBOT THEN PICKS UP
ONE TIP AT A TIME
AND DELIVERS IT TO NOZZLES.
THE NOZZLES PUMP A PASTE
CALLED FLUX ONTO IT.
ANOTHER ROBOT PLACES A PIECE
OF SOLDER METAL ON THE FLUX.
THE NEXT ROBOT DELIVERS THE
TIPS
TO THE SAW-BLADE BODY.
ELEMENTS MELT THE SOLDER METAL
AND FLUX
TO FUSE THE CARBIDE TIPS
TO THE TEETH.
IT'S A TECHNIQUE CALLED
BRAZING.
TEETH WITH CARBIDE TIPS
LAST LONGER
WITHOUT LOSING THEIR
SHARPNESS.
CIRCULAR BLADES FOR SAWMILLS
HAVE A LARGER
AND DIFFERENT DESIGN.
THEY BRUSH FLUX
AROUND A SIDE HOLE
AND THEN PLACE SOLDERING METAL
ON AN ELONGATED CARBIDE TOOTH.
THEY BRAZE THE TOOTH
TO THE FLUX-COATED HOLE
AND INSTALL SEVERAL MORE
OF THESE CARBIDE SIDE TEETH.
THE SIDE TEETH WILL ENABLE
THIS SAWMILL BLADE
TO TEAR THROUGH BIG LOGS.
THE SMALLER CIRCULAR-SAW BLADE
NOW SPINS ON AN AXLE
WHILE A SPRAY NOZZLE
SANDBLASTS IT.
THE SANDBLASTING
CLEANS THE SURFACE
AND GIVES THE BLADE
A BRUSHED TEXTURE.
A MECHANICAL FINGER NOW MOVES
ONE OF THE BLADE'S TEETH
INTO POSITION FOR SHARPENING.
A GRINDING WHEEL
TAPERS EACH TOOTH.
A DIFFERENT WHEEL MOVES IN
AND GRINDS THE OUTSIDE
DIAMETER
OF THE BLADE.
THE GEOMETRIC ANGLE
OF THE GRINDING CAN VARY,
DEPENDING ON THE TYPE OF BLADE
BEING MADE.
THE GRINDING WHEEL THEN HONES
THE FACE OF EACH TOOTH
TO GIVE IT A SHARPER EDGE.
NEXT, A STRAIGHTENING
SPECIALIST
POUNDS OUT ANY REMAINING BUMPS
IN THE BLADE...
...AND DOUBLE-CHECKS IT
WITH A STRAIGHTEDGE TOOL.
HE WIPES OFF ANY SMUDGES
AND THEN HOLDS THE BLADE
TO THE LIGHT
AND EXAMINES IT TO CONFIRM
THAT IT HAS NO FLAWS.
A LASER THEN ETCHES THE
COMPANY
INSIGNIA ONTO THE BLADE.
AND NOW THE CIRCULAR-SAW BLADE
IS READY FOR ITS CLOSE-UP.
A CAMERA FOCUSES ON THE TEETH
AND SENDS THE PICTURE
TO A COMPUTER.
IT ANALYZES THE CUTTING ANGLE
AND THE CLEARANCE OF EACH
TOOTH
TO MAKE SURE
EACH ONE MEASURES UP.
THE RESULT
IS CIRCULAR-SAW BLADES
THAT SHOULD BE ABLE TO KEEP
THEIR EDGE ON THE JOB.
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