Are All Bobbins the Same? A Guide to Sewing Machine Bobbins

22 min read

A number of confusing gadgets available are sewing machines. What exactly is it? because there are simply numerous buttons tiny parts and knobs to pull or push. This is why users often do not know the purpose of one button from the other. We recognize that not knowing the sewing machine’s entire function can lead to problems later on.

A bobbin is just one of the things that a lot of people ignore or fail to grasp. It’s among the smallest components of the sewing machine. That could be the reason they think it’s insignificant. In reality, it’s one of the most crucial parts and we’ll explain the reasons.

To help ease our readers’ lack of understanding concerning bobbins we’ve prepared this detailed guide. We’ll provide as much information as we can begin with the basics of what they are, then proceeding to their forms and their uses. So, let’s dive into it.

What Is a Bobbin?

What Is a Bobbin

What is an”bobbin? It is a tiny wood or plastic wheel with an elongated design. Its primary purpose is to keep the thread. There’s a specific area on the cylinder that the thread is wrapped around. There are also a number of winder mechanisms for bobbins that are able to wind the thread around there. However, many prefer to work it out manually. This means taking out the bobbin then winding it up with a thread, then placing it back. Thus, bobbins can be detached components.

The machine functions by catching the thread that is at the bottom of the bobbin (and the top thread from the needle). Therefore, the bobbin is an essential element because the entire procedure of making stitches is dependent upon it.

While it may appear to be it’s the most insignificant component of the whole machine, it’s not. A bobbin is equipment that can be used for multiple purposes Here’s the exact thing it can accomplish.

What Does the Bobbin Do on a Sewing Machine?

What Does the Bobbin Do on a Sewing Machine

In the preceding section, the primary purpose of Bobbins is to hold the thread or yard. It does not require both of these materials. You can weave with any material that can be used for weaving.

In the event that it is equipped with the required weaving material A bobbin pulls the thread through the plate before connecting it to the top thread. However, a bobbin cannot perform this task by itself. It must work in conjunction with another component of the machine, the spool holders. The spool holder typically will hold threads from either the side or from the top, and the bobbin holds it under. This creates an anchor for a thread while the sewing machine creates stitches.

Sewing Bobbin Sizes

Sewing Bobbin Sizes

We’re aware that there is a myriad of bobbins to pick from. One of the main elements that help us identify them is the significant differences in their dimensions.

The dimensions of a bobbin could differ, and there may be several factors that decide the size. For instance, the size of a bobbin’s case could determine the dimensions that the bobbin will be. If it’s too big the bobbin won’t fit inside the casing. In contrast, when it’s too small it will slide inside the casing, and sewing won’t be possible.

Most of the time the dimensions of a bobbin are matched to the exact style and model of a particular sewing machine (the one it was intended to be used for). So, it’s crucial to be aware of the class of the machine prior to purchasing the Bobbin. We’ll now discuss their sizes and ways to distinguish between them.

How to Tell Bobbin Size

For some who are able to distinguish the bobbins from their size is difficult. However, others manage it easily. It can be an issue in certain situations. We want to assist and offer some tips and tricks we’ve collected over the years.

The most efficient way to determine the size of a bobbin is by taking an examination of the thickness. Certain FW Bobbins are simple to identify since they are smaller than other bobbins. People who are aware of the kind and class of their machine may test every bobbin. If the machine is L class bobbins, and there are bobbins that are compatible, they will be 3/4 inches.

The most important thing is finding a method to label the bobbins, and then store them for later use. Color-grading is among the options that proved beneficial for us. This means that every type and size of bobbin should be in an individual container (preferably with various colors).

Another way to mark the bobbins is to use nail polish to put tiny dots on each. There are a variety of colors to use for this purpose as well.

Bobbin Sizes Chart

There are many different dimensions of sew-on Bobbins. While there could be additional variants and subtypes in these sizes, let us only mention the most popular ones.

We have the bobbin style L. These bobbins measure 0.350 inches tall as well as 0.910 millimeters in size.

There is a style M-bobbin which is used by people on medium and large-sized sewing machines. They are used to stitch upholstery, heavy fabric canvas, leather, and canvas. This is why their dimensions are slightly larger. They measure 0.430 inches high and around 1.000 inches wide.

Thirdly, There are Class bobbins with the same diameter as Style L ones. But their height is 0.310 inches.

Then, we are left with class fifteen (A style) that measure 0.460 inches tall as well as 0.780 inches across. They are the largest of all three, but their dimensions may vary based upon the machine used.

As we’ve discussed how big these styles of bobbins We think it’s the right time to look into their specifics. Let’s look at this in the next section.

Sewing Machine Bobbin Types and Styles

We’ve established that bobbins are available in various styles and classes to be used with particular sewing equipment. The styles differ in terms of height, shape, and size. Furthermore, there are some classes that are universal, while others can only be used with certain machines. There are four common kinds of bobbins. They are according to the following. We know their dimensions therefore we’ll leave the details.

The first thing to note is that we have a 15 class Bobbin. It is a very popular style and the layout is quite simple and simple. The top and bottom of this bobbin are entirely flat. The components are made of either made of metal or plastic.

There’s the L Class style which is nearly universal. It’s flat in design and also lets it fit into the two types of loading.

The third thing is that we have an M Class design. This is fascinating since it’s often used for industrial machines. The reason it’s as popular with traditional sewing machines is the dimensions. The dimensions of its diameter allow the bobbin to accommodate more thread than the other bobbins.

The final bobbin type is called the 66 Class. Its design is peculiarly specific and only people with a Singer machine can utilize it. It is designed to work with models that are top-loaded due to its rounded design.

Metal vs. plastic. Metal

Visually, all bobbins are similar. However, in terms of their design and the materials which they’re constructed, there are some distinct differences. You can choose to use either steel or plastic bobbins however their use is based on the model of the sewing machine. For instance, older models don’t work well with bobbins made of plastic. What’s the reason? It’s true that they begin well but they loosen as time passes. In the end, you’ll see an abundance of jerking which can cause imperfections in the stitches. The stitches could be pulled out or exhibit noticeable tension differences. Even if bobbins made of plastic are suitable for older versions, the quality of the stitch isn’t ideal and there’s a possibility that an issue could occur.

On the other hand, modern machines are extremely compatible with plastic bobbins thanks to their design. The makers of these contemporary models constantly strive to ensure that their products are as diverse and as compatible as is possible. It’s still an excellent idea to put an extra thread on bobbins made of plastic to make them more durable. It reduces the likelihood of them being swung around.

In the case of metal bobbins, they’re generally stronger and more durable. But, they’re no less prone to problems (that those made of plastic have to face). They are prone to moving when they’re empty. However, they’re definitely an ideal alternative to older vintage machines as they’re significantly heavier.

Do Sewing Machines come with Bobbins?


Many sewing machine manufacturers offer different accessories to their machines. Certain of the accessories become the integral component of the package, whereas others aren’t. Bobbins are in the latter category.

There’s a reason that customers must buy bobbins in a separate manner as manufacturers market them as separate items. But, some sewing machine brands may offer one or two bobbins as part of their promotional package. However, we haven’t seen any of them recently.

Where on a Sewing Machine Does the Bobbin Case Go?

Bobbin cases are generally removable components that must be removed for replacement in order to replace the bobbin. There are a variety of elements that influence the placement of the case for a bobbin. This includes the model of a sewing machine and the dimensions that the bobbin. Bobbin cases are either “front-loading” or “side loading cases.

Front-loading Bobbin cases are the most popular type, and their opening is on the right side of the machine. This is the side that is in front of the user.

Furthermore, side loading bobbins work in the same way. The only distinction is that sideloading bobbins have a smaller hole on the top of the machine. This is the area in which it is that the machine’s needle will go downwards. It is important to keep in mind that these bobbins with side loading don’t work with front loaders. However, front-loading bobbin cases are compatible when used with side loaders. It’s not exactly common however that’s just how it works.

Are Sewing Machine Bobbins Universal or Interchangeable?

It’s a popular myth that Bobbins are interchangeable, or universal. It would be a great advantage to be able to swap the bobbin for another. It’s not an option because every machine’s bobbin must be in line with the bobbin it is attached to. We are aware that even the slightest variation can result in problems over the long term. What causes this?

For instance, when machines use plastic bobbins, the tension is different from those which use metallic Bobbins. If users decide to switch between both the tension could fall off and cause a mess in the stitching. Also, if a particular bobbin is too high it could affect the stitch’s pattern negatively. This is particularly the case for machines with drop-in bobbins.

We suggest that you utilize the bobbins that the manufacturer of the sewing machine have mentioned. So, users will be able to ensure that nothing interferes with the operation of their machines.

How to Replace a Sewing Machine Bobbin

Do Sewing Machines Come with Bobbins

Replacing bobbins on sewing machines can differ from one machine to another. But the fundamental principle must be identical for every model. So, we’ll provide steps that will teach users how to perform it correctly.

The first step is to take off the cover of the bobbin, pressing the button just to the left. Once the cover appears it will give the users enough space to unload the old bobbin and then insert an alternative one.

After inserting the Bobbin the users must ensure that the bobbin rotates counterclockwise as they are pulling it. The thread should pass through the first slot and then return towards the left. The user should grip onto the top of the bobbin with a gentle hold and then drag in the slot in the second.

The final step is to pull the thread from the rear to the back of your machine. It’s quite simple.

How to Fill a Sewing Machine Bobbin

Filling a bobbin with a needle is easy and straightforward as long as you follow the right instructions. The most important thing to remember is that you wind your bobbin prior to threading the needle and machine. Here’s how to do it.

Then, we’ll put the thread spool on the spool pin, then place its cap on the edge of the spool. This stops the thread from getting caught and is crucial to ensure that users do this.

The next step is to push the bobbin winder’s pin to the left side and ensure that it’s in a firm position. Then, we can thread the thread from the spool into its a guide for the thread. After that, we’ll be able to place the bobbin into the pin and push the pin that winds the bobbin to the left. Then, it’s important to secure the thread’s end and then gently turn on the speed control.

Once the desired amount of thread has been wound, all we need to do is to move the bobbin to the left, then take it off. This is pretty much it.

How Much Thread Does a Sewing Machine Bobbin Hold?

The issue of the number of yards of thread a bobbin’s thread can hold is very common with this sewing group. The number of yards is related to specific factors including the tension setting as well as thread size and speed.

Professional pre-wound bobbins typically have more thread than regular bobbins. The reason is that professional bobbins always strive to achieve accuracy. In the case of the home versions, the standard thread length is anywhere between 35 to 60 yards. There is a chance that a bobbin can contain more than. We believe that anything longer than 60 yards is unnecessary.

How Does a Sewing Machine Pick up the Bobbin Thread?

In order to create an edging in order to form a seam, the needle must move the thread in a continuous manner across and up. A lot of people wonder what’s happening within the machine as the needle is moving. The entire process appears to suggest there’s some kind of magic involved. It’s an easy mechanism working.

There’s a hook underneath the needle which spins and grabs it from below. It then turns it around a different thread and then reels it back. When joined, these two threads create loops and that’s how the stitch is created.

The thread is wound by an assortment of pulleys and gears that are connected. Bobbins are one of the gears.

How to Adjust Sewing Machine Bobbin Tension

When it comes to changing the tension of the bobbin people can make use of an inserted screwdriver to turn the screw. It is important to keep in mind that some inconveniences may occur during the process. For instance, the thread of the bobbin could appear to be slightly on one side, or it may become looped.

To address the initial problem, users have to rotate the screw clockwise to increase tension. The angle of the turning is between 30 and 45 degrees.

To resolve the second issue, users need to rotate the screw counterclockwise in order to release the tension. The angle should be identical (around 45 °).

Sewing Machine Bobbin Problems and Solutions

Bobbin Thread Is Loose

A thread of bobbin that is loose is commonplace when sewing. There are many reasons why it occurs. The most common reason is that the machine isn’t threaded correctly. If this is the case, the user should reset the upper thread tension dial, and then rethread it all.

Another reason could be that the thread and needle aren’t suitable for the fabric that is being used. To resolve this it is recommended that the user verify that the installation of the bobbin is right. Furthermore, the bobbin must be compatible with your machine, and so it’s best to verify that too.

Bobbin Is Not Catching

The people who have this issue should keep the thread inside your needle towards the left. While doing this they must place the needle so that it can pick up the thread of the bobbin. It could be difficult to determine if the thread from the bobbin came out or whether it did not. If this happens, users need to simply take the darning needle, and make sure to put it through the foot pressure. The thread that runs through the bobbin is there and they’ll have to straighten it. Then, everything will function exactly as it is supposed to.

Bobbin Is Not Spinning

If a bobbin doesn’t spin There could be a variety of reasons. It could be that something is blocking the bobbin, or the gears may be worn out. Whatever the reason the best thing to do is bring the machine to a repair shop.

There were a lot of people searching for some DIY solution to this issue We strongly suggest against it. This could further harm the machine and could make the repair shop cost more.

The only thing people could do is search for any signs of lint, and then possibly clean the area. Lint is typically the culprit in such situations and it’s a good idea to look for it.

Bobbin Thread Keeps Breaking

We’ve seen numerous reports where people claimed they believed that it was the thread responsible for breaking the thread. This could be the case. We believe, however, that the tension on the bobbin is too tight , and this is the reason why the thread splits. To stop that the thread breaks, users have to loosen the tension. We’ve already covered how to do this and we’ll leave the part about loosening up.

Thread Is Stuck Around the Bobbin

If a thread becomes trapped in the bobbin region first step is to unzip the casing of the bobbin. Then, users must always attempt to rethread the thread since it resolves the majority of problems immediately. In order to do this, it is necessary to take the bobbin off and examine it. If they find any kind of knots or loops, they should simply pull the thread away and then make sure it’s all smooth. If the problem persists, even after rethreading, then they may have a problem with their machine. If that’s the situation, it’s a great idea to take the machine to a repair shop.

Bobbin Case Fell Out

If a bobbin case is ripped out, there are three pieces that are loose and need to be fixed into the right arrangement. The most crucial piece is that one that appears like a crescent moon. For the purpose of putting it back, it is necessary to adjust the knob on the right side. The piece that is inside the Bobbin Case must fit with the “crescent moon” one.

After that’s completed after that, the piece to be put back is the one that appears like a large circle (the largest of three). Once it’s returned to its place, users must lock it by pulling the arms of plastic toward the center.

Last but not least, the final thing to replace is the bobbin itself and we know how to do it.

Bobbin Bunches Up

It might sound repetitious but the simplest solution to a thread that is clumping up is to simply restart it. We’ve already mentioned that 90% of issues can be solved with rethreading and should become the primary thing you do.

The thread could be bunching up due to it not getting through the discs of tension correctly. So, tension is at fault and can be corrected by changing the thread.

Bobbin Keeps Jamming

Bobbin Keeps Jamming

A lot of people make a rookie mistake of not holding the thread’s end before beginning sewing a seam. The result is that the thread that is on the top gets pulled into the bobbin’s area and can cause chaos. To avoid jamming the bobbin it is recommended to just hold the thread loosely for the initial few stitches.

Another reason that a bobbin can’t stop jamming could be due to an issue with the machine’s threading. Rethreading remains a viable option and could be a solution, so those who are interested ought to try it.

Bobbin Loops

Alongside poor threading and the presser foot, one of the causes for loops could be the needle. The needle could be slightly bent or may not be the correct needle for the fabric being used. A change in the needle is most likely will resolve the issue.

Bobbin Keeps Knotting

Knotting is in essence the same thing as bunching. Thus, the same strategies are applicable. If the bobbin is knotting then the user can replace the bobbin’s threads or adjust the tension. The tension that is on the top of the fabric can be due to knotting that happens in the bobbin. If it’s at the lower side, this is most likely caused by the thread that is on top.

Final Words

We’d like to wrap up this lengthy article by stating that we’re not true experts but. We’re still learning however, we’ve gained all the knowledge needed throughout the many years. These are just a few tricks and tips that have helped us through this time. So, we have decided to share them with the world. We really hope our readers could discover something new about bobbins through us.

Did this article help you? If yes, it would be a huge help for you to make sure to share this article with others. We’re also always looking forward to hearing the things you’ve had to share. This is why we invite you to post your feedback in the box below.



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