How It's Made (2001–…): Season 3, Episode 10 - Wind Generators/PVC Gloves/Thermo-Formed Glass/Fire Trucks - full transcript
Find out how wind generators, PVC gloves, thermo-formed glass and fire trucks are made.
CAPTIONS PAID FOR BY
DISCOVERY COMMUNICATIONS, INC.
Narrator:
TODAY ON "HOW IT'S MADE"...
WIND GENERATORS.
PVC GLOVES.
THERMOFORMED GLASS.
AND FIRE TRUCKS.
WIND GENERATORS
HARNESS THE POWER OF THE WIND
TO PRODUCE ELECTRICITY.
AS THE TURBINE'S BLADES REVOLVE,
THEY DRIVE A ROTOR
THAT GENERATES POWER.
THIS CAN CHARGE
A SET OF BATTERIES
OR EVEN FEED
A TRANSMISSION GRID.
WIND POWER IS A RENEWABLE ENERGY
SOURCE THAT DOESN'T POLLUTE.
THIS TYPE OF WIND GENERATOR
IS A RECREATIONAL MODEL
DESIGNED TO POWER A BOAT
OR A COTTAGE
WITH UP TO 500 WATTS
OF ELECTRICITY.
TO MAKE THE PROPELLER,
THEY LAY A TEMPLATE
ON A PLANK OF WESTERN CEDAR,
A ROT-RESISTANT WOOD
THAT'S FLEXIBLE AND DURABLE,
YET LIGHTWEIGHT ENOUGH
FOR THE SLIGHTEST BREEZE
TO SET IT SPINNING.
AFTER TRACING, THEY DRILL A HOLE
AT EACH END AND IN THE MIDDLE,
THEN REMOVE THE TEMPLATE AND DO
A ROUGH CUT USING A BAND SAW.
THEY PUT THE TEMPLATE
BACK IN PLACE,
USING THOSE HOLES THEY DRILLED
TO ALIGN AND SECURE IT IN PLACE.
USING A ROUTER THIS TIME,
THEY DO A PRECISION CUT.
THE PLANK OF WOOD NOW HAS
THE CONTOUR OF A PROPELLER.
THE NEXT STEP
IS TO FORM THE PROFILE.
TO DO THAT, THEY BOLT THE WOOD
ONTO THE RIGHT SIDE
OF A SPECIALLY DESIGNED DEVICE
CALLED A
PROPELLER-CARVING MACHINE.
ON THE LEFT SIDE
IS A MODEL PROPELLER.
AFTER ADJUSTING THE MODEL
TO THE PROPER ANGLE,
THEY START TO CUT.
AS THE MACHINE'S ROLLER
RUNS OVER THE MODEL,
IT GUIDES A SHAVER TO CARVE
THE WOOD EXACTLY LIKE THE MODEL.
IT TAKES ABOUT EIGHT PASSES
TO GET THE PROPELLER'S PROFILE
JUST RIGHT.
YOU CAN SEE THE PROFILE WELL,
ONCE THEY'VE MARKED AND CUT OFF
THE EXCESS ON THE ENDS.
ONE SIDE IS FLAT,
WHILE THE OTHER IS CURVED
LIKE AN AIRPLANE'S WING.
NOW THEY WIDEN THE HOLE
IN THE MIDDLE OF THE PROPELLER
AND SAND OFF THE RIDGES
LEFT BY THE CARVING
USING A LOW-PRESSURE
INFLATABLE DRUM SANDER.
IT'S THE ONLY TYPE
FLEXIBLE ENOUGH
TO REALLY GET INTO THE CURVES.
NEXT THEY CHECK THE BALANCING.
WATCH HOW A MERE PENNY CAN THROW
OFF THIS PERFECT EQUILIBRIUM.
FINALLY, A COAT
OF WATERPROOF EPOXY PAINT --
THE KIND USED
ON THE HULLS OF BOATS.
NOW THEY ASSEMBLE
THE ALTERNATOR,
THE COMPONENT
THAT GENERATES ELECTRICITY
WHEN THE PROPELLER SPINS.
THEY WRAP INSULATION
AROUND WHAT'S CALLED
THE "PROPORTIONAL
ELECTRONIC REGULATOR"
AND THEN INSTALL IT,
ALONG WITH WIRING,
INTO THE ALTERNATOR'S CASING.
THIS REGULATOR CONTROLS THE
ELECTRICAL CHARGE AND CURRENT.
THE PROPELLER
SPINS THIS ROTOR SHAFT,
CREATING AN ELECTRICAL CHARGE
THAT SENDS A CURRENT FROM
THE ALTERNATOR TO THE BATTERIES.
ONCE THE CASING'S BOLTED SHUT,
THEY MOUNT A COOLING FAN
ON THE SHAFT'S PROTRUDING AXLE.
THIS FAN WILL EXPEL THE HEAT
ALL THAT SPINNING GENERATES.
NEXT THEY ASSEMBLE THE PARTS
THAT MAKE UP WHAT'S CALLED
THE "LOLLY SHAFT" --
THE AXIS ON WHICH
THE PROPELLER SITS.
THIS AXIS ENABLES THE PROPELLER
TO PIVOT TOWARD THE DIRECTION
OF THE WIND
WITHOUT TWISTING THE WIRES
THAT RUN TO THE BATTERIES.
FINALLY, THEY CONNECT THE WIRES
FROM THE LOLLY SHAFT
TO THE ALTERNATOR.
THIS RUBBER COVER
PROTECTS THE CONNECTION
FROM THE ELEMENTS.
NOW THEY ASSEMBLE WHAT'S CALLED
THE PROPELLER GOVERNOR --
A KEY COMPONENT THAT PREVENTS
THE PROPELLER FROM OVERSPINNING
AND BREAKING DOWN IN HIGH WINDS.
WHEN THE PROPELLER
SPINS TOO FAST,
THE CENTRIFUGAL FORCE
PULLS ON THESE SPRINGS.
THIS ACTIVATES
THE BRAKING FLAPS,
GENERATING DRAG
TO SLOW THE PROPELLER DOWN.
AGAIN, PRECISION BALANCING
IS CRITICAL.
OTHERWISE, YOU'LL HAVE
A DAMAGING VIBRATION.
AFTER APPLYING
THE MANUFACTURER'S DECAL,
THEY MOUNT
THE PROPELLER'S RUDDER
ONTO THE BACK END
OF THE WING GENERATOR'S FRAME.
ON THE OTHER END,
THEY INSTALL THE ALTERNATOR,
FOLLOWED BY THE PROPELLER
AND PROPELLER GOVERNOR,
BOTH PAINTED BLACK
TO PROTECT THE WATERPROOF
COATING UNDERNEATH
FROM THE SUN'S
DAMAGING U.V. RAYS.
Narrator: POLYVINYL CHLORIDE,
COMMONLY KNOWN AS "PVC,"
IS A DURABLE MATERIAL
SIMILAR TO PLASTIC.
PVC GLOVES ARE WATERPROOF --
EVEN CHEMICAL-PROOF.
ALL KINDS OF LABORERS WEAR THEM,
FROM COMMERCIAL FISHERMEN
TO OIL-REFINERY WORKERS.
PVC GLOVES ARE COMFORTABLY
FLEXIBLE, YET STURDY.
PRODUCTION BEGINS
AT THE CUTTING STATION
WITH STACKED SHEETS
OF COTTON FLANNEL.
USING A HYDRAULIC CUTTING
MACHINE AND A SERIES OF DIES,
WORKERS SLICE THROUGH SOME
20 LAYERS IN ONE FELL SWOOP,
CUTTING OUT THE PIECES REQUIRED
TO MAKE COTTON GLOVES.
THOSE GLOVES
WILL EITHER BE SOLD AS IS
OR USED AS LININGS
FOR PVC GLOVES.
THE NEXT STEP
IS TO SEW THE PIECES TOGETHER.
IT TAKES A SPEEDY SEAMSTRESS
JUST 30 SECONDS PER HAND.
NEXT THEY SEW ON A WRIST
MADE OF A STRETCHY,
COTTON-AND-LYCRA KNIT.
THIS SEAMSTRESS WORKS
THE WRISTING MACHINE SO QUICKLY,
WE HAD TO ASK HER TO SLOW DOWN
SO THAT WE COULD ACTUALLY SEE
WHAT SHE'S DOING.
THROUGHOUT THE SEWING PROCESS,
THESE COTTON GLOVES
HAVE BEEN INSIDE OUT.
THIS NEXT MACHINE
TURNS THEM RIGHT-SIDE IN,
TRANSFERRING THEM
ONTO A HEATED HAND FORM.
THE MACHINE THEN PRESSES
EACH GLOVE ONTO THE FORM.
THE GLOVES DROP DOWN
TO A CONVEYOR BELT BELOW.
IT TRANSPORTS THEM TO A WORKER,
WHO INSPECTS THEM AND PAIRS
THEM UP -- LEFT AND RIGHT.
ELSEWHERE IN THE FACTORY,
WORKERS PREPARE
THE PVC SOLUTION.
THE RECIPE VARIES
ACCORDING TO THE GLOVE MODEL,
BUT GENERALLY CONSISTS
OF COLORING
AND FIVE TO EIGHT
DIFFERENT CHEMICALS.
THEY ADD IN ANTIBACTERIAL,
ANTIFUNGAL SOLUTION
TO COMBAT ODOR
FROM HAND PERSPIRATION.
TO APPLY THE PVC,
WORKERS SLIP A METAL FORM
INTO THE THUMB OF EACH LINING,
THEN PUT THE LINING
ONTO A THUMBLESS HAND FORM.
IF THE HAND AND THUMB FORMS
WERE IN ONE PIECE,
IT WOULD BE DIFFICULT
TO REMOVE THE STIFF PVC GLOVE
WITHOUT TEARING.
THE LININGS GO THROUGH
WHAT'S CALLED THE SINGER --
A PROPANE FLAME THAT BURNS OFF
ANY DUST OR LOOSE THREADS.
THEN IT'S INTO THE PVC BATH.
THE BASIN OF LIQUID PVC MOVES
UPWARD, COATING THE LINERS.
AS THE BASIN DESCENDS,
THE EXCESS DRIPS OFF.
THEN THE GLOVES GO FOR A SPIN
UNDER INFRARED LAMPS
FOR 45 SECONDS.
THE SPINNING
SPREADS THE PVC UNIFORMLY
SO THAT IT DOESN'T ACCUMULATE
ON THE TIPS OF THE FINGERS,
FORMING CLUMPS.
AFTER A SECOND COAT,
THE GLOVES PASS THROUGH
A PROPANE-FIRED FURNACE
FOR ABOUT 20 MINUTES
AT 370 DEGREES FAHRENHEIT,
THEN THROUGH A COOLING CHAMBER
FOR FIVE MINUTES.
FOR GLOVE MODELS
WITH EXTRA-STRONG GRIP,
THEY BLOW PVC CHIPS
ONTO THE FIRST COAT OF PVC
WHILE IT'S STILL WET.
WHEN THE GLOVES
GO THROUGH THE FURNACE,
THE HEAT EMBEDS THE CHIPS.
AFTER COOLING,
THE GLOVES ARE DRIED AND CURED
AND READY TO HANDLE
A HARD DAY'S WORK.
Narrator:
DECORATIVE GLASS OBJECTS
CAN BE BLOWN OR THERMOFORMED --
TWO VERY DIFFERENT
GLASSMAKING TECHNIQUES.
IN GLASS BLOWING,
THE ARTISAN SHAPES HOT GLASS
BY ROLLING IT
AND BLOWING AIR INTO IT.
THERMOFORMING
IS MORE OF A MOLDING PROCESS,
BETTER SUITED
FOR MAKING FLAT OBJECTS.
WHEN YOU LOOK AT THESE
MAGNIFICENT PIECES,
IT'S HARD TO BELIEVE THEY BEGIN
AS RUN-OF-THE-MILL WINDOW GLASS.
IT COMES IN READY-MADE PANELS
IN THICKNESSES RANGING FROM 1/10
TO 4/10 OF AN INCH.
THE FIRST STEP IS TO MEASURE
THE OVERALL DIMENSIONS
OF THE GLASS PANEL,
THEN DIVIDE IT INTO PIECES,
EACH SLIGHTLY LARGER
THAN THE OBJECT IT WILL BECOME.
THEY'LL TURN THIS PANEL
INTO LARGE DECORATIVE PLATES,
SO THEY DIVIDE IT
INTO THREE SQUARES,
EACH ABOUT 14 INCHES
IN DIAMETER.
THEY PLACE EACH SQUARE
OVER A PAPER PATTERN.
USING A GLASS CUTTER, THEY SCORE
THE SHAPE OF THE PLATE.
THEN THEY APPLY PRESSURE
WITH A RUBBER MALLET
TO SEPARATE THE GLASS
ALONG THE SCORE LINE.
THEY CUT AWAY THE EXCESS,
BREAKING IT OFF
WITH A FEW GENTLE TAPS.
NOW THEY POSITION
THE PLATE-SHAPED GLASS
OVER A DRAWING
AND BEGIN THE ARTWORK.
FIRST THEY TRACE THE OUTLINE.
NOW THEY EMBELLISH THE DESIGN
AND FILL IN THE DETAILS.
THEY USE ENAMEL PAINTS
SPECIFICALLY DESIGNED
FOR PAINTING ON GLASS.
ONCE THE BRUSHWORK'S DONE,
THEY USE A PAINT GUN
TO APPLY THE BACKGROUND COLORS
AND SHADING.
THE GLASS HAS BEEN CUT
AND DECORATED,
BUT IT'S STILL PERFECTLY FLAT,
SO THE FINAL STEP IS TO MOLD IT
USING EXTREME HEAT,
HENCE THE TERM "THERMOFORMED."
THE MOLD THEY USE IS MADE
OF FIREPROOF MATERIALS
DESIGNED TO WITHSTAND HIGH
TEMPERATURES INSIDE THE OVEN,
KNOWN AS A KILN.
THEY CAREFULLY LAY THE GLASS
OVER THE MOLD.
THEY MOLD SEVERAL DIFFERENT
PIECES AT THE SAME TIME.
IN THE INTENSE HEAT OF THE KILN,
THE GLASS WILL MELT
AND TAKE ON
THE EXACT SHAPE OF THE MOLD
RIGHT DOWN TO THE MOST INTRICATE
TEXTURAL DETAIL.
THESE SMALL PIECES OF GLASS
WILL BECOME THE PAINT POTS
ON THIS GLASS REPLICA
OF AN ARTIST'S PALETTE.
IT TAKES AN HOUR AND A HALF
FOR THE KILN TEMPERATURE
TO CLIMB TO A SCORCHING
1,550 DEGREES FAHRENHEIT.
AT PEAK TEMPERATURE,
THEY BRIEFLY OPEN THE KILN
TO MAKE SURE THAT EVERYTHING
IS PROGRESSING WELL.
THE GLASS AT THIS PHASE SHOULD
BE THE CONSISTENCY OF TAFFY
AND GLOWING BRIGHT RED.
IF IT IS,
THEY CAN CLOSE THE KILN
AND BEGIN THE COOLING PHASE.
SIX HOURS LATER,
THE GLASS PIECES HAVE HARDENED
INTO THE SHAPE AND TEXTURE
OF THE RESPECTIVE MOLDS.
THESE PLATES, SPOON RESTS,
AND OTHER PIECES
ARE COOL ENOUGH
TO COME OUT OF THE KILN.
THE BEAUTY OF THERMOFORMED GLASS
LIES IN THE STRIKING COMBINATION
OF TRANSPARENCY
AND VIBRANT COLOR.
ADD TO THAT
THE ENDLESS SHAPE POSSIBILITIES,
AND YOU'VE GOT
TRULY FUNCTIONAL ART.
Narrator: THERE ARE DIFFERENT
TYPES OF FIRE TRUCKS.
PUMPERS HOOK UP TO FIRE
HYDRANTS, BOOST THE PRESSURE,
THEN SHOOT WATER OUT
THROUGH HOSES.
LADDER TRUCKS
ELEVATE FIREFIGHTERS
ON EITHER A LADDER OR PLATFORM.
RESCUE TRUCKS HAVE TOOLS
TO CUT THROUGH METAL
AND CLEAR OBSTRUCTIONS.
EARLY FIREFIGHTERS
COULDN'T DO MUCH MORE
THAN PASS BUCKETS OF WATER
FROM MAN TO MAN.
THE 1720s
SAW THE ARRIVAL OF WAGONS
CARRYING WATER TANKS
AND HAND PUMPS.
THOSE NEWFANGLED PUMPS
COULD SPEW OUT
AN IMPRESSIVE 60 GALLONS
OF WATER PER MINUTE --
ABOUT WHAT YOU'D GET
FROM TWO GARDEN HOSES.
THE FIRST HORSE-DRAWN FIRE
TRUCKS WITH STEAM-POWERED PUMPS
WENT INTO SERVICE IN 1852.
GAS-POWERED TRUCKS REPLACED THEM
IN THE EARLY 1900s.
THIS PUMPER TRUCK CAN DELIVER
ALMOST 1,600 GALLONS OF WATER
PER MINUTE.
MECHANICAL ENGINEERS USUALLY
CUSTOM-DESIGN FIRE TRUCKS
TO SUIT THE PARTICULAR NEEDS
OF THE FIRE DEPARTMENT
PLACING THE ORDER.
THE TRUCK'S BODY IS MADE
FROM SHEETS OF MARINE-GRADE
ALUMINUM 2/10-INCH THICK.
FOLLOWING
THE TECHNICAL DRAWINGS,
WORKERS CUT THE ALUMINUM PANELS
TO THE SIZES REQUIRED,
NOTCHING CERTAIN CORNERS
AT A 90-DEGREE ANGLE.
WORKERS WELD THE PIECES TOGETHER
TO FORM WHAT'S KNOWN
AS THE CREW CAB.
THE CREW CAB NOT ONLY CARRIES
THE FIREFIGHTERS,
IT ALSO HOUSES THE CONTROL PANEL
FOR THE WATER SYSTEM.
MEANWHILE, OTHER WORKERS MEASURE
AND THEN CUT PIECES OF ALUMINUM
TO BUILD THE SUBFRAME
THAT WILL SUPPORT THE CREW CAB
FROM UNDERNEATH.
THEY WELD THE PARTS TOGETHER.
INSTALLING THE STEPS,
WORKERS LEAVE A GAP
OF ABOUT HALF AN INCH
TO ENABLE WATER TO DRAIN DOWN.
THEY LINE
THE STORAGE COMPARTMENTS
WITH ALUMINUM SHEETS,
USING A SANDER TO MAKE TEXTURED
CIRCLES ON THE SMOOTH SURFACE.
THIS PATTERN
WILL CAMOUFLAGE THE SCRATCHES
THAT MOVING EQUIPMENT IN AND OUT
WILL INEVITABLY CREATE.
THEY USE A MACHINE
CALLED A PRESS BRAKE
TO BEND THE SHEETS
TO THE REQUIRED SHAPE.
THEN, USING WHAT'S KNOWN
AS A PUNCH PRESS,
THEY CUT HOLES
FOR THE BUILT-IN LIGHTS,
THE DOOR HANDLES,
AND THE VARIOUS CONTROL KNOBS.
WORKERS NOW ASSEMBLE THE PIECES
AND MAKE ANY NECESSARY
ADJUSTMENTS
BEFORE PAINTING,
RATHER THAN AFTER,
TO AVOID DAMAGING THE FINISH.
AFTER THIS FINE-TUNING,
THEY'LL DISASSEMBLE EVERYTHING
AND SEND THE PARTS
TO THE PAINT DEPARTMENT.
AFTER THAT, THEY'LL PUT IT ALL
CAREFULLY BACK TOGETHER.
THE FULL-SCALE ASSEMBLY
CAN NOW BEGIN,
STARTING WITH THE WATER PUMP.
IT ARRIVES HERE READY-MADE
FROM THE SUPPLIER.
NEXT COMES THE CREW CAB.
THIS ONE ISN'T FOR THE PUMPER,
BUT RATHER FOR A YELLOW
RESCUE VEHICLE.
THE PIPES THAT LEAD
TO AND FROM THE WATER PUMP
GO INTO A THREADING MACHINE.
THE PIPES ARE PART GALVANIZED
STEEL, PART STAINLESS STEEL.
ONCE THEY'RE THREADED,
THEY'RE READY TO BE SCREWED
INTO THE PUMP'S WATER OUTLETS.
THE DRIVE SHAFT --
THAT LONG PIECE
COMING FROM THE TRANSMISSION --
PERFORMS ITS USUAL JOB
OF TURNING THE REAR AXLE
WHEN THE TRUCK IS IN MOTION.
IT ALSO POWERS THE WATER PUMP
WHEN THE TRUCK IS PARKED,
FIGHTING A FIRE.
THIS CONTROL BOX RUNS THE FIRE
TRUCK'S ELECTRICAL SYSTEM,
INCLUDING THE FLASHING
EMERGENCY LIGHTS.
EACH WIRE IS COLOR-CODED,
NUMBER-CODED,
AND FUNCTION-CODED.
WORKERS RUN THE WIRES
FROM THE BOX TO THE CONTROL
PANEL IN THE CREW CAB.
THEN THEY HOOK UP THE ODOMETER,
SPEEDOMETER,
AND OTHER DASHBOARD INDICATORS.
THEY INSTALL
WATER-PRESSURE GAUGES,
ADAPTERS FOR CONNECTING
THE HOSES TO THE WATER SYSTEM,
AND PRESSURE-RELEASE VALVES
FOR ADJUSTING WATER PRESSURE.
LO AND BEHOLD,
A SHINY, NEW FIRE TRUCK
BUILT TO A DEPARTMENT'S
EXACT SPECIFICATIONS.
ONLY THERE'S ONE THING THE
CLIENT DIDN'T HAVE TO SPECIFY --
THAT IT BE PAINTED
FIRE-ENGINE RED.
IF YOU HAVE ANY COMMENTS
ABOUT THE SHOW,
OR IF YOU'D LIKE TO SUGGEST
TOPICS FOR FUTURE SHOWS,
DROP US A LINE AT...
DISCOVERY COMMUNICATIONS, INC.
Narrator:
TODAY ON "HOW IT'S MADE"...
WIND GENERATORS.
PVC GLOVES.
THERMOFORMED GLASS.
AND FIRE TRUCKS.
WIND GENERATORS
HARNESS THE POWER OF THE WIND
TO PRODUCE ELECTRICITY.
AS THE TURBINE'S BLADES REVOLVE,
THEY DRIVE A ROTOR
THAT GENERATES POWER.
THIS CAN CHARGE
A SET OF BATTERIES
OR EVEN FEED
A TRANSMISSION GRID.
WIND POWER IS A RENEWABLE ENERGY
SOURCE THAT DOESN'T POLLUTE.
THIS TYPE OF WIND GENERATOR
IS A RECREATIONAL MODEL
DESIGNED TO POWER A BOAT
OR A COTTAGE
WITH UP TO 500 WATTS
OF ELECTRICITY.
TO MAKE THE PROPELLER,
THEY LAY A TEMPLATE
ON A PLANK OF WESTERN CEDAR,
A ROT-RESISTANT WOOD
THAT'S FLEXIBLE AND DURABLE,
YET LIGHTWEIGHT ENOUGH
FOR THE SLIGHTEST BREEZE
TO SET IT SPINNING.
AFTER TRACING, THEY DRILL A HOLE
AT EACH END AND IN THE MIDDLE,
THEN REMOVE THE TEMPLATE AND DO
A ROUGH CUT USING A BAND SAW.
THEY PUT THE TEMPLATE
BACK IN PLACE,
USING THOSE HOLES THEY DRILLED
TO ALIGN AND SECURE IT IN PLACE.
USING A ROUTER THIS TIME,
THEY DO A PRECISION CUT.
THE PLANK OF WOOD NOW HAS
THE CONTOUR OF A PROPELLER.
THE NEXT STEP
IS TO FORM THE PROFILE.
TO DO THAT, THEY BOLT THE WOOD
ONTO THE RIGHT SIDE
OF A SPECIALLY DESIGNED DEVICE
CALLED A
PROPELLER-CARVING MACHINE.
ON THE LEFT SIDE
IS A MODEL PROPELLER.
AFTER ADJUSTING THE MODEL
TO THE PROPER ANGLE,
THEY START TO CUT.
AS THE MACHINE'S ROLLER
RUNS OVER THE MODEL,
IT GUIDES A SHAVER TO CARVE
THE WOOD EXACTLY LIKE THE MODEL.
IT TAKES ABOUT EIGHT PASSES
TO GET THE PROPELLER'S PROFILE
JUST RIGHT.
YOU CAN SEE THE PROFILE WELL,
ONCE THEY'VE MARKED AND CUT OFF
THE EXCESS ON THE ENDS.
ONE SIDE IS FLAT,
WHILE THE OTHER IS CURVED
LIKE AN AIRPLANE'S WING.
NOW THEY WIDEN THE HOLE
IN THE MIDDLE OF THE PROPELLER
AND SAND OFF THE RIDGES
LEFT BY THE CARVING
USING A LOW-PRESSURE
INFLATABLE DRUM SANDER.
IT'S THE ONLY TYPE
FLEXIBLE ENOUGH
TO REALLY GET INTO THE CURVES.
NEXT THEY CHECK THE BALANCING.
WATCH HOW A MERE PENNY CAN THROW
OFF THIS PERFECT EQUILIBRIUM.
FINALLY, A COAT
OF WATERPROOF EPOXY PAINT --
THE KIND USED
ON THE HULLS OF BOATS.
NOW THEY ASSEMBLE
THE ALTERNATOR,
THE COMPONENT
THAT GENERATES ELECTRICITY
WHEN THE PROPELLER SPINS.
THEY WRAP INSULATION
AROUND WHAT'S CALLED
THE "PROPORTIONAL
ELECTRONIC REGULATOR"
AND THEN INSTALL IT,
ALONG WITH WIRING,
INTO THE ALTERNATOR'S CASING.
THIS REGULATOR CONTROLS THE
ELECTRICAL CHARGE AND CURRENT.
THE PROPELLER
SPINS THIS ROTOR SHAFT,
CREATING AN ELECTRICAL CHARGE
THAT SENDS A CURRENT FROM
THE ALTERNATOR TO THE BATTERIES.
ONCE THE CASING'S BOLTED SHUT,
THEY MOUNT A COOLING FAN
ON THE SHAFT'S PROTRUDING AXLE.
THIS FAN WILL EXPEL THE HEAT
ALL THAT SPINNING GENERATES.
NEXT THEY ASSEMBLE THE PARTS
THAT MAKE UP WHAT'S CALLED
THE "LOLLY SHAFT" --
THE AXIS ON WHICH
THE PROPELLER SITS.
THIS AXIS ENABLES THE PROPELLER
TO PIVOT TOWARD THE DIRECTION
OF THE WIND
WITHOUT TWISTING THE WIRES
THAT RUN TO THE BATTERIES.
FINALLY, THEY CONNECT THE WIRES
FROM THE LOLLY SHAFT
TO THE ALTERNATOR.
THIS RUBBER COVER
PROTECTS THE CONNECTION
FROM THE ELEMENTS.
NOW THEY ASSEMBLE WHAT'S CALLED
THE PROPELLER GOVERNOR --
A KEY COMPONENT THAT PREVENTS
THE PROPELLER FROM OVERSPINNING
AND BREAKING DOWN IN HIGH WINDS.
WHEN THE PROPELLER
SPINS TOO FAST,
THE CENTRIFUGAL FORCE
PULLS ON THESE SPRINGS.
THIS ACTIVATES
THE BRAKING FLAPS,
GENERATING DRAG
TO SLOW THE PROPELLER DOWN.
AGAIN, PRECISION BALANCING
IS CRITICAL.
OTHERWISE, YOU'LL HAVE
A DAMAGING VIBRATION.
AFTER APPLYING
THE MANUFACTURER'S DECAL,
THEY MOUNT
THE PROPELLER'S RUDDER
ONTO THE BACK END
OF THE WING GENERATOR'S FRAME.
ON THE OTHER END,
THEY INSTALL THE ALTERNATOR,
FOLLOWED BY THE PROPELLER
AND PROPELLER GOVERNOR,
BOTH PAINTED BLACK
TO PROTECT THE WATERPROOF
COATING UNDERNEATH
FROM THE SUN'S
DAMAGING U.V. RAYS.
Narrator: POLYVINYL CHLORIDE,
COMMONLY KNOWN AS "PVC,"
IS A DURABLE MATERIAL
SIMILAR TO PLASTIC.
PVC GLOVES ARE WATERPROOF --
EVEN CHEMICAL-PROOF.
ALL KINDS OF LABORERS WEAR THEM,
FROM COMMERCIAL FISHERMEN
TO OIL-REFINERY WORKERS.
PVC GLOVES ARE COMFORTABLY
FLEXIBLE, YET STURDY.
PRODUCTION BEGINS
AT THE CUTTING STATION
WITH STACKED SHEETS
OF COTTON FLANNEL.
USING A HYDRAULIC CUTTING
MACHINE AND A SERIES OF DIES,
WORKERS SLICE THROUGH SOME
20 LAYERS IN ONE FELL SWOOP,
CUTTING OUT THE PIECES REQUIRED
TO MAKE COTTON GLOVES.
THOSE GLOVES
WILL EITHER BE SOLD AS IS
OR USED AS LININGS
FOR PVC GLOVES.
THE NEXT STEP
IS TO SEW THE PIECES TOGETHER.
IT TAKES A SPEEDY SEAMSTRESS
JUST 30 SECONDS PER HAND.
NEXT THEY SEW ON A WRIST
MADE OF A STRETCHY,
COTTON-AND-LYCRA KNIT.
THIS SEAMSTRESS WORKS
THE WRISTING MACHINE SO QUICKLY,
WE HAD TO ASK HER TO SLOW DOWN
SO THAT WE COULD ACTUALLY SEE
WHAT SHE'S DOING.
THROUGHOUT THE SEWING PROCESS,
THESE COTTON GLOVES
HAVE BEEN INSIDE OUT.
THIS NEXT MACHINE
TURNS THEM RIGHT-SIDE IN,
TRANSFERRING THEM
ONTO A HEATED HAND FORM.
THE MACHINE THEN PRESSES
EACH GLOVE ONTO THE FORM.
THE GLOVES DROP DOWN
TO A CONVEYOR BELT BELOW.
IT TRANSPORTS THEM TO A WORKER,
WHO INSPECTS THEM AND PAIRS
THEM UP -- LEFT AND RIGHT.
ELSEWHERE IN THE FACTORY,
WORKERS PREPARE
THE PVC SOLUTION.
THE RECIPE VARIES
ACCORDING TO THE GLOVE MODEL,
BUT GENERALLY CONSISTS
OF COLORING
AND FIVE TO EIGHT
DIFFERENT CHEMICALS.
THEY ADD IN ANTIBACTERIAL,
ANTIFUNGAL SOLUTION
TO COMBAT ODOR
FROM HAND PERSPIRATION.
TO APPLY THE PVC,
WORKERS SLIP A METAL FORM
INTO THE THUMB OF EACH LINING,
THEN PUT THE LINING
ONTO A THUMBLESS HAND FORM.
IF THE HAND AND THUMB FORMS
WERE IN ONE PIECE,
IT WOULD BE DIFFICULT
TO REMOVE THE STIFF PVC GLOVE
WITHOUT TEARING.
THE LININGS GO THROUGH
WHAT'S CALLED THE SINGER --
A PROPANE FLAME THAT BURNS OFF
ANY DUST OR LOOSE THREADS.
THEN IT'S INTO THE PVC BATH.
THE BASIN OF LIQUID PVC MOVES
UPWARD, COATING THE LINERS.
AS THE BASIN DESCENDS,
THE EXCESS DRIPS OFF.
THEN THE GLOVES GO FOR A SPIN
UNDER INFRARED LAMPS
FOR 45 SECONDS.
THE SPINNING
SPREADS THE PVC UNIFORMLY
SO THAT IT DOESN'T ACCUMULATE
ON THE TIPS OF THE FINGERS,
FORMING CLUMPS.
AFTER A SECOND COAT,
THE GLOVES PASS THROUGH
A PROPANE-FIRED FURNACE
FOR ABOUT 20 MINUTES
AT 370 DEGREES FAHRENHEIT,
THEN THROUGH A COOLING CHAMBER
FOR FIVE MINUTES.
FOR GLOVE MODELS
WITH EXTRA-STRONG GRIP,
THEY BLOW PVC CHIPS
ONTO THE FIRST COAT OF PVC
WHILE IT'S STILL WET.
WHEN THE GLOVES
GO THROUGH THE FURNACE,
THE HEAT EMBEDS THE CHIPS.
AFTER COOLING,
THE GLOVES ARE DRIED AND CURED
AND READY TO HANDLE
A HARD DAY'S WORK.
Narrator:
DECORATIVE GLASS OBJECTS
CAN BE BLOWN OR THERMOFORMED --
TWO VERY DIFFERENT
GLASSMAKING TECHNIQUES.
IN GLASS BLOWING,
THE ARTISAN SHAPES HOT GLASS
BY ROLLING IT
AND BLOWING AIR INTO IT.
THERMOFORMING
IS MORE OF A MOLDING PROCESS,
BETTER SUITED
FOR MAKING FLAT OBJECTS.
WHEN YOU LOOK AT THESE
MAGNIFICENT PIECES,
IT'S HARD TO BELIEVE THEY BEGIN
AS RUN-OF-THE-MILL WINDOW GLASS.
IT COMES IN READY-MADE PANELS
IN THICKNESSES RANGING FROM 1/10
TO 4/10 OF AN INCH.
THE FIRST STEP IS TO MEASURE
THE OVERALL DIMENSIONS
OF THE GLASS PANEL,
THEN DIVIDE IT INTO PIECES,
EACH SLIGHTLY LARGER
THAN THE OBJECT IT WILL BECOME.
THEY'LL TURN THIS PANEL
INTO LARGE DECORATIVE PLATES,
SO THEY DIVIDE IT
INTO THREE SQUARES,
EACH ABOUT 14 INCHES
IN DIAMETER.
THEY PLACE EACH SQUARE
OVER A PAPER PATTERN.
USING A GLASS CUTTER, THEY SCORE
THE SHAPE OF THE PLATE.
THEN THEY APPLY PRESSURE
WITH A RUBBER MALLET
TO SEPARATE THE GLASS
ALONG THE SCORE LINE.
THEY CUT AWAY THE EXCESS,
BREAKING IT OFF
WITH A FEW GENTLE TAPS.
NOW THEY POSITION
THE PLATE-SHAPED GLASS
OVER A DRAWING
AND BEGIN THE ARTWORK.
FIRST THEY TRACE THE OUTLINE.
NOW THEY EMBELLISH THE DESIGN
AND FILL IN THE DETAILS.
THEY USE ENAMEL PAINTS
SPECIFICALLY DESIGNED
FOR PAINTING ON GLASS.
ONCE THE BRUSHWORK'S DONE,
THEY USE A PAINT GUN
TO APPLY THE BACKGROUND COLORS
AND SHADING.
THE GLASS HAS BEEN CUT
AND DECORATED,
BUT IT'S STILL PERFECTLY FLAT,
SO THE FINAL STEP IS TO MOLD IT
USING EXTREME HEAT,
HENCE THE TERM "THERMOFORMED."
THE MOLD THEY USE IS MADE
OF FIREPROOF MATERIALS
DESIGNED TO WITHSTAND HIGH
TEMPERATURES INSIDE THE OVEN,
KNOWN AS A KILN.
THEY CAREFULLY LAY THE GLASS
OVER THE MOLD.
THEY MOLD SEVERAL DIFFERENT
PIECES AT THE SAME TIME.
IN THE INTENSE HEAT OF THE KILN,
THE GLASS WILL MELT
AND TAKE ON
THE EXACT SHAPE OF THE MOLD
RIGHT DOWN TO THE MOST INTRICATE
TEXTURAL DETAIL.
THESE SMALL PIECES OF GLASS
WILL BECOME THE PAINT POTS
ON THIS GLASS REPLICA
OF AN ARTIST'S PALETTE.
IT TAKES AN HOUR AND A HALF
FOR THE KILN TEMPERATURE
TO CLIMB TO A SCORCHING
1,550 DEGREES FAHRENHEIT.
AT PEAK TEMPERATURE,
THEY BRIEFLY OPEN THE KILN
TO MAKE SURE THAT EVERYTHING
IS PROGRESSING WELL.
THE GLASS AT THIS PHASE SHOULD
BE THE CONSISTENCY OF TAFFY
AND GLOWING BRIGHT RED.
IF IT IS,
THEY CAN CLOSE THE KILN
AND BEGIN THE COOLING PHASE.
SIX HOURS LATER,
THE GLASS PIECES HAVE HARDENED
INTO THE SHAPE AND TEXTURE
OF THE RESPECTIVE MOLDS.
THESE PLATES, SPOON RESTS,
AND OTHER PIECES
ARE COOL ENOUGH
TO COME OUT OF THE KILN.
THE BEAUTY OF THERMOFORMED GLASS
LIES IN THE STRIKING COMBINATION
OF TRANSPARENCY
AND VIBRANT COLOR.
ADD TO THAT
THE ENDLESS SHAPE POSSIBILITIES,
AND YOU'VE GOT
TRULY FUNCTIONAL ART.
Narrator: THERE ARE DIFFERENT
TYPES OF FIRE TRUCKS.
PUMPERS HOOK UP TO FIRE
HYDRANTS, BOOST THE PRESSURE,
THEN SHOOT WATER OUT
THROUGH HOSES.
LADDER TRUCKS
ELEVATE FIREFIGHTERS
ON EITHER A LADDER OR PLATFORM.
RESCUE TRUCKS HAVE TOOLS
TO CUT THROUGH METAL
AND CLEAR OBSTRUCTIONS.
EARLY FIREFIGHTERS
COULDN'T DO MUCH MORE
THAN PASS BUCKETS OF WATER
FROM MAN TO MAN.
THE 1720s
SAW THE ARRIVAL OF WAGONS
CARRYING WATER TANKS
AND HAND PUMPS.
THOSE NEWFANGLED PUMPS
COULD SPEW OUT
AN IMPRESSIVE 60 GALLONS
OF WATER PER MINUTE --
ABOUT WHAT YOU'D GET
FROM TWO GARDEN HOSES.
THE FIRST HORSE-DRAWN FIRE
TRUCKS WITH STEAM-POWERED PUMPS
WENT INTO SERVICE IN 1852.
GAS-POWERED TRUCKS REPLACED THEM
IN THE EARLY 1900s.
THIS PUMPER TRUCK CAN DELIVER
ALMOST 1,600 GALLONS OF WATER
PER MINUTE.
MECHANICAL ENGINEERS USUALLY
CUSTOM-DESIGN FIRE TRUCKS
TO SUIT THE PARTICULAR NEEDS
OF THE FIRE DEPARTMENT
PLACING THE ORDER.
THE TRUCK'S BODY IS MADE
FROM SHEETS OF MARINE-GRADE
ALUMINUM 2/10-INCH THICK.
FOLLOWING
THE TECHNICAL DRAWINGS,
WORKERS CUT THE ALUMINUM PANELS
TO THE SIZES REQUIRED,
NOTCHING CERTAIN CORNERS
AT A 90-DEGREE ANGLE.
WORKERS WELD THE PIECES TOGETHER
TO FORM WHAT'S KNOWN
AS THE CREW CAB.
THE CREW CAB NOT ONLY CARRIES
THE FIREFIGHTERS,
IT ALSO HOUSES THE CONTROL PANEL
FOR THE WATER SYSTEM.
MEANWHILE, OTHER WORKERS MEASURE
AND THEN CUT PIECES OF ALUMINUM
TO BUILD THE SUBFRAME
THAT WILL SUPPORT THE CREW CAB
FROM UNDERNEATH.
THEY WELD THE PARTS TOGETHER.
INSTALLING THE STEPS,
WORKERS LEAVE A GAP
OF ABOUT HALF AN INCH
TO ENABLE WATER TO DRAIN DOWN.
THEY LINE
THE STORAGE COMPARTMENTS
WITH ALUMINUM SHEETS,
USING A SANDER TO MAKE TEXTURED
CIRCLES ON THE SMOOTH SURFACE.
THIS PATTERN
WILL CAMOUFLAGE THE SCRATCHES
THAT MOVING EQUIPMENT IN AND OUT
WILL INEVITABLY CREATE.
THEY USE A MACHINE
CALLED A PRESS BRAKE
TO BEND THE SHEETS
TO THE REQUIRED SHAPE.
THEN, USING WHAT'S KNOWN
AS A PUNCH PRESS,
THEY CUT HOLES
FOR THE BUILT-IN LIGHTS,
THE DOOR HANDLES,
AND THE VARIOUS CONTROL KNOBS.
WORKERS NOW ASSEMBLE THE PIECES
AND MAKE ANY NECESSARY
ADJUSTMENTS
BEFORE PAINTING,
RATHER THAN AFTER,
TO AVOID DAMAGING THE FINISH.
AFTER THIS FINE-TUNING,
THEY'LL DISASSEMBLE EVERYTHING
AND SEND THE PARTS
TO THE PAINT DEPARTMENT.
AFTER THAT, THEY'LL PUT IT ALL
CAREFULLY BACK TOGETHER.
THE FULL-SCALE ASSEMBLY
CAN NOW BEGIN,
STARTING WITH THE WATER PUMP.
IT ARRIVES HERE READY-MADE
FROM THE SUPPLIER.
NEXT COMES THE CREW CAB.
THIS ONE ISN'T FOR THE PUMPER,
BUT RATHER FOR A YELLOW
RESCUE VEHICLE.
THE PIPES THAT LEAD
TO AND FROM THE WATER PUMP
GO INTO A THREADING MACHINE.
THE PIPES ARE PART GALVANIZED
STEEL, PART STAINLESS STEEL.
ONCE THEY'RE THREADED,
THEY'RE READY TO BE SCREWED
INTO THE PUMP'S WATER OUTLETS.
THE DRIVE SHAFT --
THAT LONG PIECE
COMING FROM THE TRANSMISSION --
PERFORMS ITS USUAL JOB
OF TURNING THE REAR AXLE
WHEN THE TRUCK IS IN MOTION.
IT ALSO POWERS THE WATER PUMP
WHEN THE TRUCK IS PARKED,
FIGHTING A FIRE.
THIS CONTROL BOX RUNS THE FIRE
TRUCK'S ELECTRICAL SYSTEM,
INCLUDING THE FLASHING
EMERGENCY LIGHTS.
EACH WIRE IS COLOR-CODED,
NUMBER-CODED,
AND FUNCTION-CODED.
WORKERS RUN THE WIRES
FROM THE BOX TO THE CONTROL
PANEL IN THE CREW CAB.
THEN THEY HOOK UP THE ODOMETER,
SPEEDOMETER,
AND OTHER DASHBOARD INDICATORS.
THEY INSTALL
WATER-PRESSURE GAUGES,
ADAPTERS FOR CONNECTING
THE HOSES TO THE WATER SYSTEM,
AND PRESSURE-RELEASE VALVES
FOR ADJUSTING WATER PRESSURE.
LO AND BEHOLD,
A SHINY, NEW FIRE TRUCK
BUILT TO A DEPARTMENT'S
EXACT SPECIFICATIONS.
ONLY THERE'S ONE THING THE
CLIENT DIDN'T HAVE TO SPECIFY --
THAT IT BE PAINTED
FIRE-ENGINE RED.
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