Comments on: Bet You Didn’t Know This Is How A Sewing Machine Works

By: Benny

Benny — Wed, 08 Feb 2012 05:28:01 +0000

Many thanks for your sharing,it’s really a good article to read,and it’s helpful
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By: Ray B

Ray B — Thu, 19 Mar 2009 21:41:53 +0000

I have investigated these and can say this the GIF is a very simple picture of what goes on. There are several different ways to get the upper thread to loop around the lower thread. There are three basic ways it has been done in the past and Singer has used all three from time to time. There is an oscillating hook that catches the upper thread behind the bobbin thread and carries it a little more than halfway around to the front of the bobbinwhere it releases to go back and catch the next needle thread. Once the thread is released the tension becomes critical becuase the thread arm pulls the needle thread w quickly up to tighten the stitch. The bobbin just sits loosely in a cage so the needle thread can pass around it.
The Pfaff and the Viking and the singer 201, 301 and most industrial sewing machines use a full rotary hook that revolves twice for each needle stroke. Once to catch the thread, fully rotate and then release it and once without any thread to get back to position to catch the thread again.
The orientation of the hook and the bobbin varies with machine design. many are perpendicular to material motion (vertical or horizontal) but some are oriented exactly the way the gif shows (only running twice as fast on the bottom as the top). The critical parts of the design are the hook timing, the thread arm pull rate, the upper and lower friction on the thread (tension at critical junctures) and the cross sectional and hole shape of the needle and its orientation to the hook.
A lot of the industrial machines can stitch 5500 stitches per minute. At those speeds even the type and twist of the thread becomes critical.
Now if someone would only explain to me how a serger works with no bobbin and four spools.

By: bluedude

bluedude — Fri, 07 Nov 2008 21:11:01 +0000

I didn’t see any links to videos??? Where were those links?

By: bobbo

bobbo — Mon, 07 Apr 2008 03:41:17 +0000

#61–Randall–why don’t you click on the two different links to video’s provided?

By: Randall Munroe

Randall Munroe — Mon, 07 Apr 2008 02:20:26 +0000

I’m with all the confused posters. This doesn’t solve the basic mystery of sewing to me — how you pass the one thread around the spool for the one while the other one is held by something. In this animation, they get around that by just not showing what’s holding the spool. But I don’t quite follow any of the couple of explanations given in words here. A video would be much better.

So what it comes down to is I wish I had an animation showing how a sewing machine worked

By: Mrs. Micah

Mrs. Micah — Mon, 24 Mar 2008 02:52:13 +0000

That’s a great gif. I knew how it worked before, but I’ve always seen it in the heat of frustration of trying to figure out where in the cycle it was screwing up…so it’s nice to see it calmly and rationally.

By: Music Dummy

Music Dummy — Mon, 25 Feb 2008 15:26:38 +0000

Great. Never knew how it worked, it just does. That goes for airplanes, ships and a lot of other things. They just work, and aren’t we lucky? Other things I know and wish I did not. Milk cows fit the category or how weeds grow faster than the good plants.

By: jgtsngh

jgtsngh — Mon, 18 Feb 2008 13:38:19 +0000

It is diffcult to visualize or understand how the thread loop made by the upper needle makes it around the thread pully inside the lower part called bobbin. This mechanism needs some modification for more explicit animation.Three dimensional model will clarify all the confsion.Indeed it is a difficult mechanism.

By: anonymous

anonymous — Sat, 26 Jan 2008 20:18:15 +0000

its funny, i love to sew, i just got a new sewing machine for Christmas in fact, and never even thought about how one works!

By: KathleenSews

KathleenSews — Thu, 17 Jan 2008 20:30:20 +0000

#18
“1) The “catcher” does not rotate 360 Degrees- it reciprocates in a half moon arc (most important fact).”

The “catcher” is a “Rotary Hook.” Some bobbin assemblies are oscillating, as in the above explanation, and some are rotating and turn a full 360 degrees.

My Pfaff has a rotating bobbin hook. It catches a loop of the top thread when the needle comes down and brings half of it in front of the bobbin and bobbin case and holds the back part of the loop above the bobbin and bobbin case until the complete 360 degree turn brings the hook back up to the top and releases the thread.

By: KathleenSews

KathleenSews — Thu, 17 Jan 2008 14:07:54 +0000

#14
“But on the few occasion I have tried to use one of these beasts, there have been many expletive laced conversations between me and machine when the bobbin gets screwed up.”

Before beginning a seam, make sure the needle is in its highest position. Make sure you have at least 4″ of bobbin thread and 4″ of top thread pulled out. Hold them both firmly and start sewing. This will prevent both threads from laying loosely in the bobbin case and tangling.

On some machines or with some fabrics, do this plus start sewing in the middle of a scrap of fabric, feeding the project fabric under the presser foot abutting the starter scrap.

By: KathleenSews

KathleenSews — Thu, 17 Jan 2008 14:01:34 +0000

#13
“The bobbin thread should be the same thread as used on the spool. Same size and weight or they will not stitch properly.”

True only for garment sewing in order to get a nice seam that presses flat. I have used heavy threads in the bobbin to get lovely effects. I keep a separate, marked bobbin case for this so I can loosen the tension to allow heavy threads and narrow ribbon to feed through. I sew with the wrong side up.

When dong fancy zig-zag stitches, I use a thin but strong lingerie thread in the bobbin, use my spare bobbin case and tighten the tension. I loosen the tension for the upper thread so some of the upper thread can be seen on the underside.

Wonderful creative device, the sewing machine. Hard to use, though, on a bus or doctor’s office.

By: Jesus Campos

Jesus Campos — Tue, 15 Jan 2008 15:21:24 +0000

So anti-gravity was invented in the 1800′s to make this bobbin work. I wonder if would get more MPG if my car didn’t require a shaft for it wheels? You know; less friction! Oh, wait a minute I still have to deal with asphalt and concrete roads. Damm!

By: lherrin

lherrin — Tue, 15 Jan 2008 14:23:27 +0000

I have sewn for 50 years and never knew how it worked.
Absolutely Amazing.

By: ElphieFae

ElphieFae — Tue, 15 Jan 2008 03:45:11 +0000

THANK YOU!

I had always kind of wondered what happened in there, but I’m not much of a domestic soul, so I never used one often enough to care.