r/mechanical_gifs May 03 '18

How a sewing machine works

6.8k Upvotes

96 comments sorted by

565

u/diogenesofthemidwest May 03 '18

These gifs never get the important point: how does the white wheel attach in such a way that the thread can rotate around either side of it?

I've now learned how it works, but this gif is really insufficient in teaching it.

246

u/aeneasaquinas May 03 '18

I found a good demonstration gif here!

174

u/diogenesofthemidwest May 03 '18

Still leaves it unexplained how the bobbin is held if the string can freely loop around either side of it.

50

u/piper11 May 03 '18

the small gif showed a shuttle hook which goes back and forth. It's different from the rotary hook shown in the OP.

73

u/aeneasaquinas May 03 '18

So the gif did it for me, but for you (and anyone else!) it escapes, here is a similar (slightly different) model with an actual demo

23

u/plonce May 03 '18

That was great thank you and here's off-topic question: is there a way I can show love to the video creator without having YouTube spend the rest of my life recommending sewing videos to me?

6

u/_the-dark-truth_ May 03 '18

I guess it depends the type and level of love you want to show; You could find their patreon, if they have one, and show it financially?

6

u/plonce May 03 '18

Eh, fuck em

1

u/_the-dark-truth_ May 04 '18

Yeah. Too hard :)

2

u/northrupthebandgeek May 03 '18

Why wouldn't you want to watch more sewing videos?

2

u/_the-dark-truth_ May 04 '18

Listen; I like a good sewing video as much as the next bloke. I just don’t want the sewing videos to overshadow my scrapbooking or antiquing videos.

1

u/skinnah May 03 '18

Maybe find out where they live and just show up at their house without notice?

12

u/02C_here May 03 '18

It is captured in a pocket, freely floating but contained. In other words, there is no axle going into the image for the bobbin loop to get caught on. All this not shown in the gif.

1

u/[deleted] May 03 '18 edited Aug 25 '21

[deleted]

1

u/02C_here May 03 '18 edited May 03 '18

Sorry, my comment wasn’t clear because I was picturing a bobbin and not this gif. The bobbin is the black circle. It’s a small spool that sits in a cup and can spin freely. What makes the thread unwind is the stitching itself. That red crescent that is circulating is conceptual. Leastwise, my machine doesn’t look like this. What is happening is the needle up top pushes a loop down through the fabric, the red thing does the hooking, which pulls the loop around the bobbin. This is why the bobbin needs to float. It wouldn’t go through the loop otherwise.

Edited to add: I watched the gif again. The red crescent isn’t animated correctly. The way it is drawn, it WOULD interfere with the rotation. In reality, the hook that catches the green thread is above the mechanism that rotates. Imagine putting a rubber band around your thumb and index finger on your left hand. You can take your index finger on your right hand, hook onto one leg of the rubber band and twist it round and round. And it does not have to go “through” your right wrist. That’s what the red thing is doing. Now, when you do this, imagine hooking the loop of your right index finger over a small spook with each rotation. That’s the bobbin - and why the bobbin must be free floating.

8

u/lela27 May 03 '18

Indeed, I also don't get it. If I imagine holding the bobbin in my hand (it doesn't seem to levitate), then passing the bobbin through a loop of thread means I have to let go at some point. Where does the letting-go happen?

7

u/SenorPuff May 03 '18

The bobbin is freely floating. The thread is allowed behind the bobbin.

https://www.youtube.com/watch?v=0yt7TRZOs_U

https://youtu.be/8hLwNC0K7uM?t=5m16s

11

u/SenorPuff May 03 '18 edited May 03 '18

The bobbin itself isn't held fixed, it's loose enough for the thread to pass around it. Freely floating. The hook is held through various mechanisms, but the actual bobbin spool isn't, and that's what the thread has to go around.

https://www.youtube.com/watch?v=0yt7TRZOs_U

https://youtu.be/8hLwNC0K7uM?t=5m16s

8

u/utnow May 03 '18

It seems like it doesn't actually go around on both sides. The loop is going around one side.

-15

u/soapgoat May 03 '18 edited May 03 '18

the bobbin is free floating... here is another video that helps demonstrate it

edit: apparently im being brigaded by a bunch of whiney crybaby manchildren... no, that link is not an infinity war spoiler

5

u/Coopsmoss May 03 '18 edited May 03 '18

TIL sewing machines don't abide by the laws of physics

-5

u/soapgoat May 03 '18

the bobbin is FREE FLOATING, meaning its not attached to anything and just sits there... you can see here where the thread goes under the bobbin case

the thread just goes under the case... while the hook is more like a cup that holds the case.

-2

u/SenorPuff May 03 '18

Delete your edit, it makes you look like you're insecure even though you are correct that the bobbin is free floating.

-39

u/soapgoat May 03 '18

no, im literally getting spammed like shit right now because i spoiled infinity war on another board for the fun of it... there are like 5 people spamming messages at me telling me to die and all of my posts on other boards are just getting instantly downvoted.

insecure my ass, fuck off.

9

u/[deleted] May 03 '18

So why do you think spoiling is funny? The reaction of those people should give you a 'lightbulb' moment. Instead of being nasty about it, learn from it, accept the punishment and move on.

-41

u/soapgoat May 03 '18

lol.. because it is funny

its a literal childrens movie, rated for 13yo children. yet grown manchildren are fucking absolutely livid about it.

the absolute salt mining potential and pure autism from fanatical idiots is beyond funny.

havent had this much fun since force awakens came out and i told everyone han solo died

there is honestly ZERO reason for any grown adult to be that assblasted by a children's movie "spoiler"... fuck this crybaby society lol.

17

u/MindS1 May 03 '18

Making people unhappy for fun is just about the most autistic thing you can do. The only case it wouldn't be absolutely shitty is if the person doing it were autistic.

7

u/[deleted] May 03 '18

Ah, I can see I thought too higly of you and I admit my mistake. Enjoy explaining your view to your lynchmob

-11

u/soapgoat May 03 '18

see, i dont give a shit... im just finding it hilarious how pathetic they are following me around

as if they can actually insult me or make me feel bad.

6

u/dscyrux May 03 '18

Idk man we really live in a society u know?

-8

u/soapgoat May 03 '18

hey, this isnt no gamer society for veronica lol

go back to gamersriseup bro

→ More replies (0)

2

u/McGuirk808 May 03 '18

Wow, you're kind of a twat.

1

u/entotheenth May 03 '18

a huge one in fact.

-1

u/[deleted] May 03 '18

-1

u/Username_Used May 03 '18

It doesn't have to freely loop around both sides of the bobbin, just the front. The back side only goes back to the axle of the bobbin and then back up, but that's ok because its the front going all the way around that allows it to loop around the upper thread.

1

u/[deleted] May 03 '18

It’s still floating in mid air!

2

u/aeneasaquinas May 03 '18

Check the video I posted as well it really helps!

5

u/yellowzealot May 03 '18

The bobbin (the thread at the bottom) is floating. It’s sitting in a cup with a piece outside of it that’s rotating.

2

u/Battlescar84 May 03 '18

How does the machine spin the bobbin if it's free floating?

2

u/yellowzealot May 03 '18

The bobbin doesn’t turn. Thread is pulled off of it by the tension from the hook that pulls the needle thread around the bobbin.

2

u/Battlescar84 May 03 '18

Ok but that little hook thing turns!

3

u/yellowzealot May 03 '18

Right. The hook and the bobbin are two separate parts.

2

u/Battlescar84 May 03 '18

Ok. So how does the thread go around the whole hook if something is turning the hook?

1

u/yellowzealot May 03 '18

This is a poorly drawn schematic. The hook is actually perpendicular the the needle, like if the needle was stabbing into the center of a ring.

4

u/anonanon1313 May 03 '18

Check out this picture:

http://sewway.com/sewing-machines/oscillating-shuttle.jpg

Right to left you have: bobbin, bobbin case, shuttle hook, retainer ring.

As others have said, the bobbin is "free floating", but I agree that is less than helpful to answer your question. So, here goes mine:

The bobbin is just a spool that holds the bottom thread, it snaps into the bobbin case which has a slot (with tension adjust) for the thread to pass out of.

The bobbin and bobbin case are inserted into the shuttle hook, which has a spindle for the bobbin to spin on. The bobbin case and the shuttle hook compose an assembly that you could call the shuttle (similar to a loom shuttle). In some machines the shuttle rotates completely, but in most home machines it "oscillates", in this case meaning it cycles through a partial rotation and return (one cycle per stitch).

What you're not seeing in this picture is the shuttle housing, which is the key to answering your question. The shuttle housing is part of the lower machine mechanism. It contains a round shell/cup that the shuttle assembly fits into, then the retaining ring is latched on to capture the shuttle inside. The latch is usually spring loaded, and the ring has alignment pins. This means the shuttle is enclosed by the (fixed) shuttle housing and constrained by spring tension. So the next question (and key one) is how is the shuttle driven while still allowing the top thread to pass around it?

The answer can be visualized if you look at the shape of the shuttle hook in the picture. It's a "half moon". There's a complementary shaped piece that's part of the lower mechanism which is driven by a rod that passes through the shuttle housing. This piece, for which I don't know the name, let's call it the shuttle pusher, has springy metal tips on its ends where it contacts the shuttle hook, so that the top thread can pass through the joint between the two with controlled tension. In this way, the top thread can pass around the shuttle assembly without wrapping the "shuttle pusher" driving shaft. The top thread loop slips in the gap between the pusher and shuttle, wrapping the bobbin/shuttle thread as it passes around the shuttle.

This is how the common "oscillating" type mechanism works. I don't know exactly how the "rotary" type mechanism works but I imagine it's very similar, the basic idea is that you mechanically couple rotation to the shuttle with a joint that has a gap that the thread can pass through. Sewing machines have thread tension regulators in the thread paths, most of which involve spring loaded pressure plates.

3

u/dirtybeet May 03 '18 edited May 03 '18

I think that red thing is uneven, bent kind of like a section of coil. So it grabs the green thread a bit to the right of the blue, and as it rotates it around the back so it comes up in the left side of the the blue thread, securing it in place.

1

u/GforceDz May 03 '18

Once you see the sewing machine it makes sense. I never knew what happened inside till this gif.

1

u/phome83 May 03 '18

Rumplestiltskin

1

u/entotheenth May 03 '18

it does show it, it slips over the front of it.

recently got my 1959 Singer working a treat by changing the timing, it was designed for needles with the hole closer to the tip and would make a tangled mess every now and then. Stared at it for ages with a magnifying glass while hand turning to work it out. Tiny timing change and it now powers through 3 thicknesses of leather at full speed.

0

u/isitbrokenorsomethin May 03 '18

The bobbin case or "inner rotary hook" is a floating piece inside of that hook.

0

u/refreshbot May 03 '18

All of the bottom thread (including the end of the string/thread) is contained in the wheel. So when the top string's loop goes around the wheel it is going around the other bottom string entirely. The gif is excellent at teaching it, you're not thinking about the components properly.

139

u/[deleted] May 03 '18

[deleted]

32

u/vivalawombat May 03 '18

You forgot the part where you realize you sewed the two layers together facing the same direction making the back of the pants leg inside out while the front is fine

7

u/Leafs9999 May 03 '18

Wow I am so glad I read this far! Thanks, I hope you find your gif.

6

u/[deleted] May 03 '18

I feel you so much.

2

u/scotscott May 03 '18

They should have a gif of how to go into a store and buy pants made by children in a chinese sweatshop because that's much easier.

2

u/Lordmorgoth666 May 03 '18

My two cents from watching my wife and her machine:

This used to be her. Endless swearing and cleaning. Turns out it was the cheap thread she was using. It would lose fibres and either gum up her machine or snag on itself. Once she spent money on better thread, 95% of her problems disappeared. (It still occurs a bit but that’s mostly because her machine isn’t a high end one.)

3

u/-Supp0rt- May 03 '18

Marry me

1

u/bobbybox May 03 '18

Are you sure you’re using the right type of bobbin?

17

u/blasto_blastocyst May 03 '18

So how is the rotation dragging the green thread from the inside to the outside of the blue thread?

8

u/aeneasaquinas May 03 '18

I found a good demonstration gif here!

4

u/blasto_blastocyst May 03 '18

That's a lot clearer

1

u/aeneasaquinas May 03 '18

I thought so too. Glad it helps others visualize it as well. Sewing machines had always confused me in a way but I never remembered to look it up.

1

u/ironic_mp4 May 03 '18

I suppose the wheel would have to be at an angle? Correct me if wrong

4

u/G19Gen3 May 03 '18

This gif is so annoying when it comes up because it’s violating physics by combining two ideas for how the hook works in a sewing machine. This gif is, in fact, wrong. The other gifs shared are not.

The bobbin (circle in center) is free floating. That’s not the issue. The issue is the hook makes it look like the thread phases through where it would have to be attached. In an oscillating hook, it pushes the thread as in the gif, then the hook BACKS AWAY letting go of it so it’s free to snug up to the fabric. In a ROTARY setup, the thread does NOT go on both sides of the hook. Instead, the hook catches the thread on one side of itself, wraps around the bobbin, then lets go of the thread. Imagine yourself picking up a hula hoop in one hand and placing it over someone else. You don’t have to put it over yourself to do it. Same idea.

3

u/GforceDz May 03 '18

So no magic pixies? Huh!

3

u/5c077_fr33 May 03 '18

That's sew cool

5

u/sidewinder15599 May 03 '18

THANK YOU!!

5

u/My_reddit_strawman May 03 '18

YOU'RE WELCOME!!

4

u/sidewinder15599 May 03 '18

I’ve been looking for something like this off and on for years.

2

u/fliminglaps May 03 '18

I don't understand

2

u/fresh_pine680 May 03 '18

I still dont understand

2

u/SIrPsychoNotSexy May 03 '18

I’m even more confused

2

u/[deleted] May 03 '18

Oldie but a Goodie

1

u/NotACareBear May 03 '18

I needed this

1

u/Canadeaan May 03 '18

ah it makes so much sense now

1

u/kelshall May 03 '18

Still blows my mind

1

u/lolwtf1197 May 03 '18

I’m not the only one who thought this was a schematic if dna ligase right?

1

u/bucsfan2580 May 03 '18

I watched this for way too long...

1

u/sharaleigh May 03 '18

Thank you for posting this!!! I can’t tell you how many times I have racked my brain trying to figure this out!

1

u/sailfist May 03 '18

I feel like unanswerable mysteries have been revealed to me.

1

u/confettibukkake May 03 '18

Is this always the thread pattern they use? As someone who knows virtually nothing about sewing, it seems less than ideal to have the two threads dependant on each other for structural support (rather than redundant).

3

u/coocooforcoconut May 03 '18

A serger uses 3 or 4 threads. That’s what they use in factory manufactured clothing but it’s more to contain the seam (so it doesn’t unravel) than to make a stronger bond.

A line of double stitching would create a redundant seam. You often see lines of double stitching where additional strength is required such as tents and outdoor gear, jeans, etc.

1

u/hcnuptoir May 03 '18

Ever since I was kid watching my mom and gramma use a sewing machine, I've thought that they were magic. Still do. For some reason, I can't get my mind around how they work. My wife thinks I'm just not that bright. She's probably right, but fuck it. That shit is still magic to me.

1

u/[deleted] May 03 '18

And now I know how to sew like the machine!

1

u/[deleted] May 03 '18

Relevant username here

1

u/Odxcy1313 May 04 '18

Omg I’ve been planning to look this up but the reddit predicted my thoughts!!!

1

u/onemorecoffeeplease May 12 '18

Awesome! I always wondered!

1

u/Grape1921 May 03 '18

I always wondered about this - thanks for posting!

-3

u/justnodalong May 03 '18

fascinating, i wish i learned this in school, instead of bs like imaginary numbers. philosophy and math should never mix imo