Original subtitles

Narrator: AROUND THE WORLD, THE RACE TO WIN WARS

AND EXPLORE THE UNIVERSE

HAS CREATED SOME OF THE MOST

INCREDIBLE PRODUCTS EVER DESIGNED,

AND WE USE THEM EVERY DAY,

UNAWARE OF THEIR AMAZING ORIGINS.

ON "INCREDIBLE INVENTIONS," THE DRUM,

ITS USE IN KEEPING TIME

BOTH MUSICALLY AND ON THE BATTLEFIELD,

THE SLINKY,

HOW A SIMPLE METAL SPRING DEFIES

THE LAWS OF PHYSICS,

AND THE FENCING SWORD,

THE DEADLY PAST OF AN OLYMPIC SPORT.

WE REVEAL THE AMAZING HISTORY

AND ENGINEERING OF THESE

INCREDIBLE INVENTIONS.

-- Captions by VITAC -- www.vitac.com

CAPTIONS PAID FOR BY DISCOVERY COMMUNICATIONS

♪♪

FROM THE NEOLITHIC ERA TO THE 21ST CENTURY,

THE DRUM HAS LIVED UP TO ITS NOISY REPUTATION.

IT'S BEEN USED BY THE ANCIENT CHINESE AND MONGOLIAN TRIBES,

THE AZTECS OF MEXICO,

AND NATIVE AMERICANS IN THE PLAINS

OF THE UNITED STATES.

Hicks: WHEN IT COMES TO DRUMS, YOU'VE GOT TO GO BACK IN TIME,

REALLY ANCIENT TIMES, AFRICA,

THE HOLLOWED-OUT LOG,

YOU KNOW, INTIMIDATING THE NEXT TRIBE,

THE ENEMY OR THE NEXT VILLAGE YOU'RE COMING.

THE NATIVE AMERICANS, WITH THEIR DRUMS,

IT'S TELLING YOU, WE'RE COMING.

Narrator: AS ONE OF THE OLDEST MUSICAL INSTRUMENTS,

A DRUM'S BASIC DESIGN HAS REMAINED

ALMOST THE SAME FOR THOUSANDS OF YEARS.

CLASSIFIED AS A MEMBRANOPHONE

BECAUSE IT CONSISTS OF AT LEAST ONE ANIMAL HIDE

THAT HAS BEEN STRETCHED AND,

WHEN STRUCK BY THE HAND OR DRUMSTICK,

PRODUCES A DEEP AND LOUD SOUND.

WHILE THE DRUM IS COMMONLY REGARDED

AS THE ROOT OF ALL MUSIC,

IT CAN'T ESCAPE ITS BLOODY PAST ON THE BATTLEFIELDS OF HISTORY.

MANY KINGDOMS, TRIBES

AND NATIONS HAVE RISEN AND FALLEN

TO THE SOUND OF A BEATING DRUM.

WELL, THE MOST SIMPLE USE FOR THE DRUM

IS MARKING TIME FOR THE REGIMENT

AND BEATING THE TIME OF THEIR DIFFERENT MOVEMENTS

WHEN THEY'RE DOING THEIR DRILL.

BOTH IN THE ENGLISH AND THE AMERICAN CIVIL WAR,

THE DRUM BEAT WAS PARAMOUNT.

IT WAS THE MOST IMPORTANT THING.

WITHOUT IT, YOU COULDN'T GET ALL OF YOUR MEN

TO PRESENT AT THE RIGHT TIME,

FIRE AT THE RIGHT TIME.

OTHERWISE, IT WOULD BE CHAOS ON THE BATTLEFIELD.

LIBERTY HAS BEEN MAKING DRUMS

IN COUNTY DURHAM, ENGLAND SINCE 2006,

AND ALL THEIR DRUMS ARE ENTIRELY HANDMADE,

MAKING THEM UNIQUE.

Street: WE BUILD THE DRUMS FROM THE RAW TIMBER,

SO WE SOURCE IN THE BIRCHES,

THE MAPLES, MAHOGANIES,

AND WE BUILD OUR KITS PLY BY PLY.

ESSENTIALLY, EVERY ELEMENT IS HANDMADE.

ALL THE TIMBERS ARE ALWAYS HANDLED BY HAND,

RIGHT TO THE FINISHING PROCESS.

IT'S A, YOU KNOW, A REALLY FINE INSTRUMENT.

Narrator: THE PROCESS BEGINS WITH THE SELECTION OF THE TIMBER

TO MAKE THE SHELL OF THE SNARE DRUM.

STRIPS OF PLYWOOD ARE MEASURED OUT

AND PRECISELY CUT TO SIZE.

THESE WILL BE LAMINATED TOGETHER

TO FORM THE DRUM SHELL.

FOR THE OUTER LAYER OF THE DRUM,

TWO STRIPS OF THE PLYWOOD

ARE LAYERED UP ON EITHER SIDE

OF A DECORATIVE BEADING STRIP

AND HELD IN PLACE USING MASKING TAPE.

EACH PLYWOOD LAYER IS COATED WITH A SPECIAL GLUE

AND CAREFULLY MANIPULATED INTO PLACE

WITHIN A SOLID-WALLED MOLD.

EACH FRAME GETS A COAT OF GLUE BY HAND

AND THEN PLACED IN THE MOLD.

EACH PLY, WE USE A SPECIFIC COMPOUND OF GLUE,

AND THEN EACH LEAF OR VENEER,

WE'VE PLACED IN THE MOLD TO MAKE THAT SPECIFIC DRUM.

SO IT DEPENDS THE TYPE, THE DESIGN OF THE DRUM,

HOW THICK, HOW MANY VENEERS.

THE MOLD'S PURPOSE IS TO APPLY EXTERNAL PRESSURE

TO THE PLYWOOD LAYERS.

THE SHELL IS LEFT TO DRY NATURALLY IN THE MOLD

FOR 24 HOURS TO ENSURE A GOOD BOND.

ONCE DRY, THE DRUM IS EXTRACTED FROM THE MOLD AND CHECKED

FOR ANY IMPERFECTIONS ON THE LAMINATE.

THE EDGES OF THE DRUM

ARE THEN PRECISELY TRIMMED USING A CIRCULAR SAW.

THE DRUM'S SURFACE IS THEN CAREFULLY SANDED BY HAND

TO ENSURE A GOOD, SMOOTH FINISH.

NEXT, THE DECORATIVE BEAD IS MASKED WITH TAPE,

AND ONE HALF OF THE DRUM

IS STAINED WITH A COLORED LACQUER.

ONCE THE LACQUER IS DRY, THE WHOLE DRUM IS COATED

WITH A LAYER OF WAX FOR PROTECTION

AND TO GIVE A SMOOTH FINISH.

WHEN THE FINISH IS COMPLETE,

THE EDGES OF THE DRUM ARE BEVELED USING A ROUTING TOOL.

THIS WILL FORM A BEARING EDGE

FOR ATTACHING THE DRUM SKINS LATER ON.

NEXT, MASKING TAPE IS APPLIED AROUND

THE CIRCUMFERENCE OF THE DRUM

SO THAT IT CAN BE MARKED UP FOR DRILLING.

A TEMPLATE IS USED TO MARK THE POSITIONS

WHERE THE DRUM WILL BE DRILLED.

MORE MASKING TAPE IS APPLIED

AT EACH POSITION AROUND THE DRUM,

AND A TEMPLATE IS USED TO MARK THE CORRECT POSITIONS

FOR DRILLING THE HOLES.

HOLES ARE DRILLED THROUGH THE DRUM

SHELL AT ALL THE MARKED LOCATIONS,

AND THEN ALL THE EXTERNAL METALWORK IS SCREWED ON AROUND

THE EDGES OF THE DRUM.

THESE ARE USED FOR ATTACHING THE DRUM HEADS

AS WELL AS THE SNARE WIRES.

NEXT, THE BOTTOM DRUM HEAD IS ATTACHED TO THE DRUM

USING A METAL HOOP,

WHICH IS SCREWED ONTO THE DRUM THROUGH THE METAL LUGS.

THE DRUMHEAD IS THEN TIGHTENED

AND TUNED TO ENSURE EVEN TENSION AROUND

THE HEAD USING A DRUM KEY.

THE WIRE SNARES ATTACH DOWN TO THE BOTTOM HEAD OF THE DRUM.

THE SNARE WIRES STAY IN CONTACT WITH THE DRUMHEAD

AND VIBRATE WHEN THE DRUM IS HIT.

IT IS THIS THAT GIVES A SNARE DRUM

ITS UNIQUE, SNAPPY SOUND.

THE FINAL STEP IS TO ATTACH THE TOP DRUMHEAD AND TUNE IT.

NOW, IT IS READY FOR A THOROUGH TEST IN A DRUM ROOM.

[ DRUM ROLL TO BACKBEAT ]

SO THERE IT IS, THE SNARE DRUM.

FROM MARCHING BAND TO ROCKSTAR,

IT REALLY IS AN INCREDIBLE INVENTION.

AFTER THE BREAK, WE EXPLORE,

HOW DID A HAPPY ACCIDENT DURING WORLD WAR II

CREATE ONE OF AMERICA'S MOST POPULAR TOYS?

Narrator: THE SLINKY, A METAL MARVEL

THAT STILL CONTINUES TO AMAZE YOUNG AND OLD ALIKE.

BUT HOW IS THIS INNOCENT TOY CONNECTED TO WORLD WAR II,

AND WHAT IS THE AMAZING SCIENCE BEHIND ITS STRANGE ABILITY

TO WALK DOWN STAIRS?

THE SIMPLE PRECOMPRESSED HELICAL SPRING,

THAT'S A COIL TO YOU AND ME,

IS FIRST INVENTED BY RICHARD JAMES WAY

BACK IN THE EARLY 1940S

WHILE HE'S WORKING WITH THE US NAVY.

AS PART OF THE WAR EFFORT,

JAMES AND HIS TEAM ARE BUSY BUILDING SPRING SHOCK ABSORBERS

TO KEEP DELICATE NAVIGATION INSTRUMENTS ON BOARD WARSHIPS

SAFE AND FREE FROM DAMAGE, EVEN IN THE HEAVIEST OF STORMS.

THE SLINKY WAS AN ACCIDENTAL INVENTION, IF YOU WILL.

IT WAS DISCOVERED BY RICHARD JAMES

WHEN HE KNOCKED OVER SOME SPRINGS.

HE REALIZED THE WAY THAT THEY WALKED ACROSS THE FLOOR

COULD BE POSSIBLY BECOMING A PRODUCT,

AND THIS PRODUCT BASICALLY WAS DESIGNED

SUCH THAT YOU COULD PLAY WITH IT.

HE SHOWED IT TO A LOT OF LITTLE KIDS.

THE CHILDREN THERE LOVED IT,

AND HE REALIZED HE WAS ONTO A WINNER.

Narrator: WITH THE EXCITEMENT OF HIS INVENTION

STILL FRESH IN HIS MIND,

JAMES AND HIS WIFE BORROW $500

AND SPEND THE NEXT YEAR RESEARCHING

AND DEVELOPING THE IDEA

SO IT'S READY FOR THE 1945 CHRISTMAS RUSH.

AT FIRST, THE BIG DEPARTMENT STORES ARE SKEPTICAL,

SO JAMES TAKES INITIATIVE BY DEMONSTRATING

HIS CREATION TO SHOPPERS,

AND BY THE END OF THE YEAR, THE SLINKY IS THE MUST-HAVE

TOY ALL ACROSS THE USA.

THE SLINKY'S FORM MAY BE SIMPLE, BUT DON'T UNDERESTIMATE

THE COMPLICATED SCIENTIFIC PRINCIPLES AT PLAY.

NUDGE THE COILED SPRING DOWN A FLIGHT OF STAIRS

AND BE PREPARED FOR A MAJOR PHYSICS LESSON.

WITH A LIFE OF ITS OWN,

THE TOY BEGINS TO MOVE BY

INDEPENDENTLY FALLING OVER ITSELF

FROM ONE STEP TO THE NEXT IN A FLUID MOVEMENT.

THE SLINKY IS DEMONSTRATING A NUMBER OF FORCES

AS IT MOVES DOWN THE STEPS.

FRICTION, INERTIA,

MOMENTUM AND POTENTIAL AND KINETIC ENERGY

ARE ALL ACTING ON THAT COILED SPRING.

AT REST, THE SLINKY IS STILL AND DOES NOT MOVE.

THIS IS CALLED INERTIA,

AND IS THE RESISTANCE OF ANY PHYSICAL OBJECT

TO CHANGE ITS STAGE OF MOTION OR REST.

INERTIA IS AIDED BY THE EFFECTS OF FRICTION,

A FORCE THAT RESISTS THE MOVEMENT OF OBJECTS

AS THEY SLIDE AGAINST ONE ANOTHER.

IN THE SLINKY'S CASE, THE AIR THAT PASSES THROUGH IT

AND THE CARPET THAT COVERS THE STEPS.

THE FACT THAT THE SLINKY IS AT THE TOP OF THE STAIRS

MEANS THE EFFECTS OF GRAVITY

ARE STORED AS POTENTIAL ENERGY

AS SPRING TENSION.

IF THIS ENERGY IS RELEASED, THE POTENTIAL ENERGY

IS CONVERTED TO KINETIC ENERGY,

THE FORM OF ENERGY GOVERNED BY MOTION,

WHICH MEANS THE SLINKY IS NOW MOVING.

SO WHY DOES THE SLINKY KEEP GOING?

WELL, AS THE SLINKY TAKES ITS DIVE DOWN

THE FIRST STEP, IT STRETCHES, THEREBY STORING ENERGY.

THAT ENERGY REACHES A POINT

WHERE IT MUST PULL THE TAIL ALONG,

FLIPPING IT OVER TO THE NEXT STEP.

NOW, MOMENTUM COMES INTO PLAY.

THIS FLIPPING ACTION CONTINUES AS THE SLINKY'S MOMENTUM

CANNOT BE STOPPED BY THE FORCES ACTING AGAINST IT,

FOR EXAMPLE THE FRICTION.

OBJECTS WITH A LARGER MOMENTUM

REQUIRE MORE ENERGY TO MOVE AND TO STOP,

WHILE THOSE WITH LOW MASS

AND VELOCITY HAVE LESS MOMENTUM,

THUS THE GREATER THE WEIGHT OF THE SLINKY

AND THE DOWNWARD ANGLE IN WHICH IT IS TRAVELING,

THE GREATER THE MOMENTUM,

WHICH IS WHY A METAL SLINKY

IS BETTER AT TRAVELING DOWN STAIRS

THAN A PLASTIC ONE.

THIS COMPLICATED BUT PLAYFUL ACTION HAS CAPTIVATED CHILDREN

EVER SINCE IT WAS FIRST INTRODUCED OVER 70 YEARS AGO,

AND ITS POPULARITY SHOWS NO SIGNS OF DECLINING.

ENOUGH SLINKYS HAVE BEEN SOLD

TO GO AROUND THE EARTH A STAGGERING 121 TIMES.

THAT'S OVER 300 MILLION INDIVIDUAL ITEMS.

THEY'VE GONE TO SPACE ON THE SHUTTLE

AND BEEN USED BY US TROOPS IN VIETNAM

AS PORTABLE RADIO ANTENNAE.

IT SEEMS THERE'S NO STOPPING

THE EXCITEMENT OF THE OLD TOY.

THE SLINKY, TRULY AN INCREDIBLE INVENTION.

COMING UP, A SPECIAL SLOW-MOTION

EXPERIMENT THAT REVEALS

JUST HOW THE SLINKY ACTUALLY WORKS.

♪♪

Narrator: THE SLINKY MIGHT HAVE BEEN FLYING --

SHOULD THAT BE FLOATING? --

OFF THE SHELVES SINCE THE 1940S,

BUT CAN IT ACTUALLY FLY -- OR MORE CORRECTLY, FLOAT?

LET'S TRY AND FIND OUT.

THE EXPERIMENT -- WE WILL DROP A LARGE SLINKY FROM A GREAT HEIGHT

AND FILM IT USING A SPECIAL SLOW-MOTION CAMERA

TO CAPTURE THE RESULTS.

TO START, A LARGE BUILDING

WITH EASY WINDOW ACCESS TO ALLOW FOR VERY SCIENTIFIC

DROPPING OF CLASSIC CHILDREN'S TOY, CHECK.

LARGE SLINKY, CHECK.

SPECIAL SLOW-MOTION CAMERA

FOCUSED AND EXPOSED

AT THE ABSOLUTE PERFECT SETTINGS TO CAPTURE

OUR SPECTACULAR SLINKY FALL, CHECK.

OUR FEARLESS TESTER ASCENDS THE STAIRS,

TAKES POSITION AND IS ALL SET FOR THE EXPERIMENT TO BEGIN.

WITH HIS ARM STRETCHED OUT AT A PERFECT 90 DEGREES

TO HIS BODY, HE LETS THE SLINKY UNRAVEL

TO ITS FULLEST EXTENT

WHILE EXPERTLY HOLDING ONTO ONE END.

HE SIGNALS THAT HE IS READY,

AND A DISEMBODIED HAND PRESSES RECORD ON THE CAMERA.

THE TEST CAN BEGIN.

OUR MAN LETS GO OF THE SLINKY AND,

LESS THAN 2 SECONDS LATER, IT HITS THE GROUND.

DID YOU SEE THE SLINKY FLOAT?

NO?

NEITHER DID WE. LET'S REVIEW THE TAPE.

NOW, SEEN AT 150 FRAMES PER SECOND,

WE CAN SEE SOMETHING AMAZING HAPPEN.

AS THE SLINKY IS RELEASED,

THE TOP OF THE TOY FALLS VERTICALLY,

AS YOU WOULD EXPECT, BUT LOOK AT THE BOTTOM.

IT'S NOT MOVING.

ASTONISHED? WELL, WE ARE.

BUT HOW IS THIS STEEL SPRING CHEATING GRAVITY?

AGAIN, SCIENCE COMES TO OUR AID.

BEFORE IT IS DROPPED,

THE BOTTOM OF THE SLINKY IS SUSPENDED,

WITH GRAVITY PULLING IT DOWN IN ONE DIRECTION

AND THE SPRING'S TENSION PULLING IT UP ON THE OTHER,

SO EQUAL AND OPPOSITE FORCES

ACT ON THE BOTTOM, LEAVING IT MOTIONLESS.

WHEN THE TOP IS RELEASED, THE INFORMATION THAT THE TENSION

HAS CHANGED TAKES A MOMENT

TO REACH THE BOTTOM OF THE SPRING.

ONCE THE WEIGHT HITS THE BOTTOM OF THE SLINKY,

IT KNOWS TO FALL TO THE BOTTOM, SO TO SPEAK.

SO THERE YOU HAVE IT. POINT PROVED.

THE SLINKY CAN FLOAT, WELL, SORT OF.

AS WE SAID BEFORE,

THE SLINKY REALLY IS AN INCREDIBLE INVENTION.

FENCING IS A SPORT OF PRECISION, STYLE AND GRACE.

WATCHING TWO WORLD-CLASS FENCERS ON THE OLYMPIC STAGE

IS SOMETHING TO BEHOLD.

HOWEVER, IT IS A WORLD AWAY FROM THE DARK HISTORY

OF DUELING THAT WAS THE PREDECESSOR OF THE SPORT.

BEGINNING WITH PREHISTORIC CLUBS AND SPEARS,

ARMED COMBAT HAS BEEN AROUND ALMOST AS LONG AS MANKIND.

THROUGHOUT HISTORY, THERE ARE PLENTY OF REFERENCES TO DUELS.

WE'VE ALL HEARD ABOUT ROMAN GLADIATORS,

BUT IT IS PERHAPS A LESSER-KNOWN FACT

THAT ROMANS FREQUENTING BATHS

OFTEN DUELED WITH STICKS,

AN EARLY SIGN OF WHAT WAS TO EVOLVE

IN TO MODERN FENCING.

DUELING IS THE ENGAGEMENT IN COMBAT

BETWEEN TWO INDIVIDUALS,

BOTH WITH MATCHING WEAPONS

AND OFTEN WITH A SET OF PRE-AGREED RULES.

DUELS ARE FOUGHT AS A WAY OF REGAINING

OR RETAINING A SENSE OF HONOR,

AS OPPOSED TO NECESSARILY KILLING THE OPPONENT.

ROMAN SOLDIERS ARE TRAINED TO THRUST INSTEAD OF CUT,

AS A RAISED-ARM CUTTING MOTION

WOULD EXPOSE VITAL ORGANS TO THE ENEMY.

THIS THRUST IS THE BASIS OF MODERN FENCING TECHNIQUE.

BY THE 14TH CENTURY,

SWORD-FIGHTING SCHOOLS ARE COMMON

IN MANY EUROPEAN COUNTRIES.

THESE ESTABLISHED A CORRECT WAY TO FIGHT WITH A SWORD,

AND THE INABILITY TO DO SO IS SEEN AS UNGENTLEMANLY.

IT WAS A FENCING INSTRUCTOR CALLED GEORGE DE SILVA

WHO ACTUALLY SAID THAT, IF A MAN CARRIES A SWORD

BUT CANNOT USE IT,

IT'S AS FULL RIDICULOUS AS A MAN

WHO CARRIES BOOKS BUT CANNOT READ.

Narrator: BY THE 19TH CENTURY,

AS DUELS BECOME LESS COMMON AND ACTIVELY DISCOURAGED,

FENCING IS INCREASINGLY RECOGNIZED AS A SPORT.

SLOWLY, THE COMBATIVE ASPECT OF FENCING FADES

UNTIL WE ARE LEFT WITH THE PURE SPORT OF TODAY.

IT BECOMES AN OLYMPIC SPORT IN 1896.

AFTER THE BREAK, WE GET STRAIGHT TO THE POINT

AND SEE HOW A MODERN FENCING SWORD IS CRAFTED.

Narrator: MODERN OLYMPIC-STANDARD FENCING

IS BROKEN INTO THREE CATEGORIES,

EACH REFERRING TO THE WEAPON USED,

AND EACH WITH THEIR OWN DIFFERING SET OF RULES.

FOIL FENCING USES A LIGHT AND FLEXIBLE SWORD.

ARMS AND LEGS AREN'T ALLOWED TO BE TARGETED,

SO ALL OF THE ACTION TAKES PLACE

WITH ACCURATE THRUSTS TO THE TORSO, NECK AND GROIN.

EPEE IS SIMILAR, BUT THE SWORD IS HEAVIER

AND THE WHOLE BODY CAN BE TARGETED.

SABRE FENCING ONLY ALLOWS ATHLETES

TO TARGET ABOVE THE WAIST

AND USES A LIGHT, CUTTING SABER SWORD.

TODAY, BECAUSE OF THE HIGH-SPEED NATURE OF THE SPORT,

AND TO ENSURE ACCURACY,

ALL JUDGING IS DONE ELECTRONICALLY.

ONE OF THE LEADING PRODUCERS

OF MODERN OLYMPIC FENCING EQUIPMENT

IS LONDON-BASED LEON PAUL.

SO WE'VE BEEN PRODUCING FENCING EQUIPMENT FOR 96 YEARS,

BUT WE'VE BEEN CREATING SWORDS

AND FORGING THE BLADES FOR ABOUT 60 YEARS NOW.

Narrator: SO HOW ARE THESE INCREDIBLE INVENTIONS ACTUALLY MADE?

THERE ARE MANY INDIVIDUAL PROCESSES INVOLVED IN PRODUCING

AN OLYMPIC-STANDARD FENCING SWORD.

IT BEGINS WITH MARAGING STEEL,

A METAL OF SUPERIOR STRENGTH AND TOUGHNESS,

YET THAT HAS A HIGH LEVEL OF MALLEABILITY.

WE USE MARAGING STEEL FOR THE OLYMPIC BLADES,

AND THAT'S BECAUSE IT HAS VERY LITTLE CARBON IN,

AND THAT MEANS LESS FLAWS ARE LIKELY TO PROPAGATE,

AND THAT MEANS THAT IT'S GOING TO LAST

A VERY LONG PERIOD OF TIME.

Narrator: THE STEEL IS FIRST CUT

TO THE CORRECT LENGTH USING A SAW.

THIS PARTICULAR AUTOMATED SAW CAN CUT MANY BLADES AT A TIME

TO PRECISELY THE RIGHT MEASUREMENTS NEEDED.

ONCE CUT, THE AREA OF THE BLADE THAT WILL FORM THE HANDLE

IS THEN HEATED TO FORM WHAT IS KNOWN AS THE TANG.

THESE TANGS ARE ROUNDED AND ALLOW FOR COMFORTABLE GRIP

OR THE ADDITION OF A MOLDED OR WOODEN HANDLE.

THE BLADE IS THEN TAKEN TO THE MAIN FORGE,

WHERE IT IS HEATED TO APPROXIMATELY

1,500 DEGREES FAHRENHEIT,

USING RADIOFREQUENCY COILS,

MUCH LIKE THE HEATING PROCESS IN A MICROWAVE.

ONCE THE METAL IS RED-HOT,

ROWS AND ROWS OF VERY STRONG HAMMERS THIN THE BLADE OUT

TO THE CORRECT PROPORTIONS

TO PRODUCE THE PERFECT FOIL SHAPE.

NOW FORMED, THE BLADE IS BEGINNING

TO RESEMBLE A RECOGNIZABLE FOIL.

THE METAL IS THEN HEAT TREATED.

THIS IS VITAL TO PRODUCING A GREAT-QUALITY BLADE.

BECAUSE THE STEEL CAN BECOME BRITTLE IN THE FORGING PROCESS,

HEAT TREATING RESTRENGTHENS THE METAL AND ALSO INCREASES

ITS FLEXIBILITY AND LONGEVITY.

THE WORLD RECORD FOR THE LONGEST LIFESPAN

OF A BLADE IS ABOUT 37,000 CYCLES,

SO THAT'S 37,000 HITS,

AND THAT RECORD IS ACTUALLY HELD BY A LEON PAUL BLADE.

Narrator: THE SURFACE OF THE BLADE IS THEN FINISHED,

FIRST IN A GRINDING MACHINE

WHICH GIVES IT A SMOOTH FINISH.

NOW THE BLADE CONTINUES

THROUGH THE SHOT PEENING PROCESS.

THIS FIRES SMALL BEADS OF GLASS AT THE STEEL

THAT CREATE A COMPOSITE RESIDUAL STRESS LAYER IN ADDITION

TO INCREASING ITS SHEEN.

THE BLADE IS TAKEN TO BE LASER ENGRAVED

WITH THE LEON PAUL STAMP,

SHOWING WHEN AND WHERE IT WAS MADE

AS WELL AS THE GRADE OF STEEL.

A WIRE THAT CONNECTS THE ELECTRONIC

TIP OF THE BLADE TO THE SENSOR IS FITTED WITH GLUE,

COMPLETING THE BLADE-MAKING PROCESS.

IT IS NOW TIME TO CREATE THE GUARD OF THE SWORD.

THIS IS MADE FROM AN ALUMINUM SHEET,

WHICH IS BENT TO SHAPE USING A HYDRAULIC PRESS,

WHICH FORMS THE PERFECT ROUNDED SHAPE

FOR PROTECTING THE HAND OF THE USER.

IT IS THEN RIVETED IN ORDER TO REINFORCE THE BASE

BEFORE BEING STAMPED WITH THE LEON PAUL LOGO.

THE BASE IS THEN POLISHED

BY RUNNING WATER OVER THE METAL,

SCRUBBING IT WITH CHINA

AND FINISHING IT OFF UNDER THE POLISHING WHEEL.

NOW THAT WE HAVE A FINISHED BLADE AND GUARD TO MATCH,

IT ALL NEEDS TO BE ASSEMBLED INTO A FULL SWORD.

THE ELECTRONIC WIRES ATTACH TO THE ELECTRONIC SOCKET,

MEANING THE SWORD IS NOW EQUIPPED

TO SCORE ELECTRONICALLY.

THIS IS FITTED ALONG WITH A CUSHION PAD AND HANDLE.

THE HANDLE CAN BE CUSTOM-MADE USING A 3-D PRINTER OR BE FITTED

WITH A MORE TRADITIONAL WOODEN HANDLE

THAT HAS BEEN HAND-WRAPPED IN LEATHER.

THE SWORD IS THEN TESTED TO ENSURE IT CONFORMS

WITH ALL THE OFFICIAL REGULATIONS.

THE FENCING SWORD,

CERTAINLY AN INCREDIBLE INVENTION.

SO THERE YOU HAVE IT,

A GLANCE THROUGH THE HIDDEN HISTORY

AND SUPER SCIENCE OF SOME AMAZING PRODUCTS

WE USE EVERY DAY,

THE DRUM, THE SLINKY, AND THE FENCING SWORD.

THEY MAY SEEM COMMON AND ORDINARY,

HOWEVER, THESE PRODUCES HELPED CHANGE THE WORLD

ONE INCREDIBLE INVENTION AT A TIME.