Transcript of YouTube Video: The Surprising Genius of Sewing Machines

- Can you explain how a sewing machine works?

I mean, think about it.

We've all seen them.

There's that little needle that's moving up

and down really fast, leaving a trail

of stitches behind them.

But if you think about it for a second,

how are they doing it?

Because the needle is never actually going fully

through the fabric.

If you're hand sewing, you have

to pass the needle up and down.

You have to let go of the needle

and grab onto it on the other side.

So in order to invent the sewing machine, we first had

to invent a whole new way of sewing.

It's one of these things that almost no one thinks about,

but is so important.

Every piece of clothing you've ever put

on virtually was made by a sewing machine.

So in this video, I'm going to explain

how sewing machines work.

And I promise when you find out, you will find it

so incredibly satisfying.

And what you'll realize is

that these machines are performing

tiny mechanical miracles every second.

A part of this video was brought to you

by KiwiCo, more about them at the end of the show.

- The foot pedal is right in front of your right foot.

You can gently rest it. It doesn't need a lot of pressure.

So easy does it, and you should be able to start going.

- All right. Ah, all right.

(sewing machine rumbling)

This is amazing.

- [Noah] I find it meditative.

- If I were going to sew two pieces

of fabric together, this is how I would do it.

Weaving the needle back

and forth through both pieces of fabric.

This is known as a running stitch,

and there are more sophisticated stitches you could do.

But if you're trying to mechanize any hand stitch, you run

into a major problem, which is

that any time you pass the needle

through the fabric, you have to release it on one side

and pick it up again on the other side.

This is almost impossible for a machine to do,

at least a machine from 200 years ago.

So in order to invent the sewing machine, we first needed

to come up with a totally new way of sewing.

And this came in three breakthroughs.

(dramatic music)

Human have been sewing clothes

for tens of thousands of years.

In 2016, researchers found a needle in a cave in Siberia

that dates back to about 50,000 years ago.

The crazy thing is

that homo sapiens didn't live in that cave.

It was inhabited by the Denisovans, a now extinct species

of early humans.

So sewing isn't just a homo sapien thing,

it is a human thing.

The needle is made of bone.

But in other regards, it looks like any modern needle,

a sharp end pierced through fabric

and an eye on the other end for the thread.

Needles have remained basically unchanged

for tens of thousands of years.

Artifacts from caves in France, ancient Egypt, Greece,

India, China, and Japan, all look about the same.

That is until 1755.

Charles Frederick Wiesenthal was a

German inventor living in England.

We're not exactly sure what motivated him,

some believe he was trying to invent a sewing machine,

but maybe he was just tired

of flipping the needle over twice every stitch.

But what he created was a needle that was sharp

on both sides, so you could pass the needle back

and forth through the fabric without flipping it over.

He patented his invention, a needle for ornamenting fabrics,

which may have sped up sewing a little.

But the two-sided needle delivered an unexpected benefit

used by all sewing machines up until this day.

It moved the eye of the needle next to the sharp tip.

But how does that help?

When I put the needle

into the fabric, the thread does go below the fabric,

but when I pull it out, the thread also gets pulled out.

So it seems like we've achieved nothing.

We need to find a way to tangle the thread

when it's at the bottom of the stitch

to stop it from pulling out.

And luckily, there are two ways of doing this.

(dramatic music)

If you can keep a loop of thread underneath the fabric,

as I pull the needle out, well then, I can move the fabric

over and pass that needle

through the loop, forming a little link.

And if I do that again, I can form a chain

of these stitches.

That is why this is known as a chain stitch.

The chain stitch was one

of the first stitches successfully performed

by sewing machines.

It's really hard to say

who invented the first sewing machine.

There were just so many people working

on the problem at the same time

and there are many competing claims.

In 1790, Thomas Saint drew detailed patent drawings

for a sewing machine design, but there is no evidence

that he ever built a prototype.

In 1814, Joseph Madersperger was granted a patent in Vienna.

It took him a decade to build the machine,

but he never commercialized it.

He spent the rest of his life trying to perfect the design.

In 1830, Frenchman Barthélemy Thimonnier

built his own version.

It created a chain stitch with a barb needle.

He was granted a patent

and set up a garment factory with 80 of his machines.

There, they began manufacturing uniforms

for the French army but this invention caused an uproar.

A mob of 200 angry tailors ransacked his factory

and destroyed all of his machines.

It took a few more decades

before sewing machines were reliable enough

to be commercially viable.

The two most reliable ways

to build a chain stitch machine were invented

at nearly the same time in 1857, when James Gibbs

and Charles Raymond received their respective patents.

It was easy enough for me to grab the loop of thread

in the model, but it's much more difficult

to design a machine to do this reliably and repeatedly.

Charles Raymond's design used a hook.

The needle punctures the fabric

and carries the thread down with it.

Then as the needle moves up, the thread between the eye

and the fabric shortens

and buckles forming a little bulge of thread.

At exactly this instant, the sharp hook catches the bulge,

stretching it into a loop.

And as the needle comes back down, the hook moves backwards

and the needle passes through the loop.

The needle comes all the way down

and then as it moves back up, the thread between the eye

and the fabric buckles again,

the hook catches this bulge pulling the thread

into a loop for the needle to pass through once more.

Gibbs had a similar design, but the hook was rotating.

So as the needle lowers the hook grabs the thread,

the rotating hook spins around, the first loop is released,

and then the hook grabs the second loop.

It took Gibbs thirty-seven prototypes, all carved outta wood

to get this incredible looper shape just right

and then that same shape was used

on over 80 models of sewing machines for 80 years.

The looper was held by pieces of metal tightly enough

that it didn't fall out, but with enough of a gap

for the thread to pass through all the way around.

We are showing a simplified model here for clarity.

But there's a flaw with this simple way

of making a chain stitch.

If the thread comes loose, you can easily pull

out all the stitching.

It's remarkable how quickly

and easily the thread gets pulled out

because there's barely any friction with the fabric.

The only friction holding each stitch in place is the loop

from the previous stitch.

So once one goes, they just all go in a chain.

So people developed more complex chain stitches

that use more thread and are more robust.

You'll likely find chain stitches holding the hem

of your jeans together.

You can also embroider beautiful patterns

with the chain stitch.

- Anything that kind of had decorative stitches is

what it was originally used for, but then it became used

for all kind of lettering and flowers.

- You're sort of doing gymnastics figuring out,

if I feel it this direction, where is my next path gonna be?

You're trying to kind of think ahead of yourself.

And I think as you become more skilled with the chains too,

that's where your work begins to look a lot more refined.

(sewing machine rumbling)

- Besides the chain stitch,

there is a completely different way to secure the thread.

And honestly, it's kind of genius.

All it requires is two separate spools of thread.

Now this spool of thread is called the bobbin.

So here's how it works.

The needle goes through two pieces

of fabric all the way down,

and then you pass the second spool of thread completely

through a loop in the top spool,

and then bring the needle back up, pull in the excess

and what we have done is interlocked

these two pieces of thread.

That's why this is known as a lock stitch.

In 1846, Elias Howe patented it

and to promote his new creation,

he staged a live sewing demonstration, him

and his sewing machine versus five seamstresses.

Howe's machine worked, but it wasn't elegant.

The machine used a curved needle, the fabric hung

down vertically, and it could only make stitches

in a straight line.

Five years later, Allen B. Wilson dramatically

improved the lock stitch sewing machine

receiving two patents, one in 1850 and one in 1851.

The first patent was

for the vibrating shuttle lock stitch machine.

Although it's called a vibrating shuttle,

it actually oscillates back and forth

and inside it is a small bobbin of thread.

As it moves forward, it catches the top thread

from the needle forming a loop and as the shuttle passes

through this loop, it creates a lock stitch

by intertwining the top thread with the lower bobbin thread.

The shuttles movement is synchronized

with the needles up-and-down motion.

The shuttle was pushed around by pieces

of metal tightly enough that it didn't fall out,

but with enough of a gap for the thread

to pass all the way around the shuttle.

This type of sewing machine was incredibly common

in the late 1800s.

Many millions of just the Singer Model 27 were made,

and they were built incredibly robustly.

There are many machines that are now

over a hundred years old that are still working.

Sewing machines were developed before the idea

of planned obsolescence took off.

The second patent that Wilson received in 1851 is the basis

for how most modern sewing machines work.

Instead of a shuttle moving back and forth, the bobbin is

inside a rotating hook.

So let's see how that works.

The needle comes down, pulling that top thread,

and it goes down really low,

and then it pops back up a little bit

creating this little bulge right here.

And when the rotating hook comes around, it is grabbed

by that rotating hook, pulling even more thread

so that this thread can pass entirely around the bobbin.

And then needle pops back up.

We pull in the excess

and we've formed another lock stitch like so.

From this, it might look like you're using more thread

from the top because when this thread comes in, you need

to pass an entire loop around the bobbin

but that thread then gets pulled back up.

So we actually filmed

in slow motion a sewing machine using a gradient thread

so you can see just how much thread is getting pulled

in from the top.

It looks like a lot, but ultimately you use the same amount

of thread from the top spool as from the bottom spool.

The tension needs to be identical

on both the top and bottom thread

so the same amount of thread is used in each stitch.

If the tension is off, the stitch won't meet perfectly

in the middle of the two fabrics leading

to a much weaker stitch.

This is true for both vibrating shuttle

and rotating hook lock stitch machines.

But what does result is a lot of friction.

You can imagine this piece

of thread is getting pulled back down

and back up a whole bunch of times with every stitch.

So what was developed was actually a groove

in the sewing needle right here

to reduce the friction between the thread and the fabric

as it has to keep getting pulled down

to go around the bobbin and then get pulled back up

when it's tensioned again.

This resulted in less fraying of both thread and fabric

and resulted in a cleaner stitch.

Practically all modern sewing machine needles have a groove

on one side.

But there's still an important piece missing.

After a stitch has been made, how do you move the fabric?

(dramatic music)

In the earliest sewing machines, the fabric would be moved

by hand after every stitch,

but that was obviously slow, inefficient,

and the stitches wouldn't have been identically spaced.

A few designs were attempted,

but the most successful one was also invented

by Allen B. Wilson.

His idea was a small piece of metal, the foot

that would press down on the fabric.

When the needle is not in the fabric, a small piece of metal

with grooves in it pushes up from below.

It grabs the fabric and then moves back a fraction

of an inch advancing it to where the next stitch should be.

This design is used

in practically all sewing machines today.

They're called feed dogs.

There are some modified versions

of this idea, like the universal feed machine used

for chain stitch embroidery.

- With these style of machines,

there's a handle underneath the machine

and it rotates the entire nose of the machine.

- [Derek] Okay.

- And this presser foot,

that will basically advance the fabric in 360 degrees.

So right now we've got this hooked up to a single motor,

but back then these cables went up to the ceiling

and were all powered by one big generator,

one big like steam power or coal powered generator.

And so I'm sure the factories were so loud.

There used to be a pin, we've taken them off just

'cause we don't need them anymore.

And what you would do is you'd pull down

and it would immediately engage the machine

because this was spinning continuously

'cause it was all hooked up by one motor.

Like nowadays, when you start a machine, you can kind

of like feather it a little bit, you can start slow.

Back then, they were going like 10,000 rpm right away.

- [Derek] You got to gotta be ready.

- Yep. Those women were heroes.

I mean, unbelievable skill.

- The most famous name associated

with sewing machines is that of Isaac Singer.

But Singer did not invent the sewing machine.

He was a shrewd businessman buying up patents

for various parts and building his company on that.

Inspired by interchangeable parts

that he saw in production of firearms,

he optimized the production process

and his company was able to drop the price

of sewing machines from a hundred dollars to around $10.

That's just over $300 in 2023 terms.

This lower price meant he could sell the machines

to families rather than to corporations.

Singer's business was also one of the earliest in the world

to offer an installment payment plan, allowing the buyer

to pay it off over a few months,

rather than paying the entire cost upfront.

Singer became one of the largest corporations in the world

and the first American multinational company.

Before the advent of sewing machines, it would take

over 12 hours to sew a single shirt.

It now takes less than 30 minutes.

In 1900, the average American family spent about 15%

of its total income on clothing.

In 2003, it was less than 4%,

but despite spending less, we own more clothes.

In 2019, the worldwide average number

of garments owned was over 130.

Each year, a hundred billion garments are produced.

And just in the US alone, 11.3 million tons

of clothing ends up in landfill.

That's nearly 35 kilograms of clothing for every man, woman,

and child that is thrown away each year.

But should we blame sewing machines?

The sewing machine is brilliant.

Invented, iterated upon, and improved by dozens of people.

They really have revolutionized the world.

All it took was inventing a completely new way to sew.

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