The basic steps to load a bobbin
A bobbin is the small spool that holds the bottom thread in your sewing machine. To load it, you wind thread onto an empty bobbin using your machine's winding mechanism, then place the wound bobbin into the bobbin case (or directly into the machine, depending on your model). The process takes about two minutes once you know where each part is.
Most machines follow the same sequence: thread the bobbin winder, wind the thread onto the bobbin until it stops automatically, remove the bobbin, and insert it into the bobbin case with the thread tail tucked under the tension spring. The exact location of these parts varies by machine type, so your manual will show you where yours are.
Key Takeaways
- Wind the bobbin on your machine's winding mechanism before inserting it, using the same thread color and weight as your top thread.
- Most bobbins wind automatically and stop when full—do not force them or overfill, as this causes tension problems.
- The bobbin case (a small metal or plastic housing) holds the bobbin and has a tension spring that the thread must pass under.
- If your machine has a drop-in bobbin, you skip the bobbin case step and place the wound bobbin directly into the machine's center.
- Incorrect bobbin loading causes loose stitches, thread breaks, and skipped stitches—so check your manual if something goes wrong.
Finding your bobbin winder and understanding your machine type
Your sewing machine has one of two designs: a bobbin case machine (older and industrial models) or a drop-in bobbin machine (most modern home machines). Knowing which you have changes where you wind and load the bobbin.
On a bobbin case machine, the bobbin winder is usually on the right side of the machine, near the top. You'll see a small wheel or spindle where you place an empty bobbin. On a drop-in machine, the winder is often in the same location, but the bobbin inserts directly into a slot in the machine's center (no separate case). Open your manual and look for the diagram labeled "bobbin winding" or "threading"—it will show you exactly where yours is. If you don't have the manual, search your machine's brand and model number online; most manufacturers post PDFs for free.
Winding thread onto the bobbin
Place an empty bobbin onto the winder spindle. The spindle usually has a small notch or groove that holds the bobbin in place. Make sure the bobbin sits flat and snug—if it's loose, it won't wind evenly.
Thread the machine as if you were sewing normally (through the tension discs, guides, and any other points your manual shows), but instead of threading the needle, guide the thread through a small hole or notch on the bobbin winder itself. This is usually marked on the machine. Holding the thread tail, press the foot pedal or turn the hand wheel to start winding. The bobbin will spin and fill with thread.
Most machines have an automatic stop—the winding slows or stops when the bobbin is full. Do not overfill it. If your machine does not stop automatically, watch the bobbin and stop when it looks full (thread should not bulge beyond the sides). Cut the thread, remove the bobbin, and trim the tail close to the bobbin.
Loading the bobbin into a bobbin case
If your machine has a separate bobbin case, it's a small metal or plastic housing that sits under the needle plate. Open or remove it according to your manual—some slide out, others unscrew. The case has a slot where the bobbin sits and a tension spring (a thin metal piece) that holds the thread.
Insert the wound bobbin into the case with the thread wound in the direction shown in your manual (usually clockwise). Pull the thread tail under the tension spring—this is the most common mistake. The thread must sit in the groove under the spring, not on top of it. If it's not under the spring, your tension will be wrong and stitches will be loose.
Once the thread is under the spring, leave a 4- to 6-inch tail hanging out. Close or reinsert the bobbin case into the machine. Some cases click into place; others screw in. Make sure it's fully seated before you sew.
Loading a drop-in bobbin
Drop-in bobbins are simpler. After winding, open the access door or plate in the center of your machine (usually under the presser foot). You'll see a small circular slot or chamber.
Insert the wound bobbin into the slot with the thread wound in the direction your manual shows. Most machines have a small notch or arrow that shows the correct orientation. The bobbin should sit flat in the chamber. Pull the thread tail up and to the side—some machines have a small hook or guide where you catch the thread. Leave a 4- to 6-inch tail.
Close the access door. The machine is now ready to sew. When you thread the needle with top thread and lower the presser foot, the needle will catch the bobbin thread and create a stitch.
What to do if the bobbin is not winding evenly
If the thread piles up on one side of the bobbin or winds too loosely, the bobbin winder spindle may be dirty or the bobbin itself may be damaged. Clean the spindle with a dry cloth and try again with a fresh bobbin. If the problem continues, the bobbin may have a crack or burr—replace it with a new one of the same size and type.
Also check that you're using the correct bobbin for your machine. Bobbins come in different sizes and styles (metal, plastic, class 15, class A, etc.), and using the wrong one causes winding problems and tension issues. Your manual lists the correct bobbin type. If you're unsure, take a wound bobbin to a fabric store and ask them to match it.
Common problems and when to call a professional
If your stitches are loose on the bottom after loading a new bobbin, the thread is probably not under the tension spring, or the bobbin case is not fully seated. Remove the bobbin, check that the thread is under the spring, and reinsert the case firmly. If stitches are still loose, the tension spring itself may be bent—this requires a professional repair.
If the bobbin thread breaks while you're sewing, the bobbin case may have a rough spot or burr inside. Stop sewing and remove the bobbin case. Run your fingernail gently inside the case—if you feel a catch or rough edge, the case is damaged and needs replacement. Do not try to sand it smooth; a professional should replace it.
If the bobbin will not wind at all, the winder spindle may be stuck or the bobbin may not be seated correctly. Make sure the bobbin is pushed all the way onto the spindle. If it still won't wind, the winding mechanism may need service—contact the machine's manufacturer or a local sewing machine repair shop.
Frequently Asked Questions
Can I use any bobbin in my machine?
No. Bobbins come in different sizes and materials (metal, plastic, snap-on, screw-on). Using the wrong bobbin causes tension problems and may damage the machine. Check your manual for the correct type, or bring your machine to a fabric store and ask them to match it.
How full should the bobbin be?
Wind the bobbin until it stops automatically, or until the thread reaches the edge of the bobbin without bulging. An overfull bobbin causes tension problems and may jam in the case. An underfull bobbin runs out of thread mid-project.
What if I don't have an empty bobbin?
Most machines come with two or three bobbins. If you've lost them or they're all in use, buy replacements at a fabric store or online. Make sure they match your machine's type. Bobbins are inexpensive (usually a few dollars each) and worth keeping extras on hand.
Do I have to wind the bobbin every time I sew?
No. Wind several bobbins at once and store them ready to use. This saves time when you're switching thread colors or running out mid-project. Keep wound bobbins in a small container so they don't unwind.
Why is my bobbin thread showing on top of my fabric?
This usually means the bobbin tension is too tight or the top thread tension is too loose. First, check that the bobbin thread is under the tension spring in the bobbin case. If it is, the tension spring itself may need adjustment—consult your manual or ask a repair professional, as adjusting tension requires care.