Threading the bobbin is the first step before you sew
The bobbin is the small spool that holds thread underneath your fabric. On a Singer machine, you wind thread onto an empty bobbin, then insert it into the bobbin case so the machine can use it during sewing. If your bobbin is not threaded correctly, your stitches will bunch, break, or look loose on the underside of your fabric.
The process has two parts: winding the bobbin with thread, and then placing it in the bobbin case. Both take less than a minute once you know where each part is on your machine.
Key Takeaways
- The bobbin winder is a small wheel or post on the side or top of your Singer machine where you wind thread onto an empty bobbin.
- You must push the bobbin winder away from the machine or flip a lever to disengage the needle before winding, or the needle will keep moving and jam.
- Wind the bobbin until it is full but not overstuffed — the thread should stop automatically when the bobbin is full on most Singer models.
- The bobbin case sits below the needle plate and holds the wound bobbin; you insert it with the thread tail facing the correct direction so the machine can catch it.
- If stitches look loose underneath your fabric, the bobbin thread is usually too loose or the bobbin is not seated all the way in the case.
Locate the bobbin winder on your machine
The bobbin winder is a small wheel or spindle attached to your Singer machine. On most Singer models, it sits on the right side of the machine near the top, or on the top of the machine itself. Look for a small post or wheel that sticks out — this is where you will place an empty bobbin.
If you cannot find it, check your machine's manual or look at the diagram printed on the inside of the machine's cover. Different Singer models place the winder in slightly different spots, but it is always visible and straightforward to reach.
Disengage the needle before you wind
Before you start winding thread onto the bobbin, you must stop the needle from moving. If the needle keeps going while you wind, the thread will jam and the bobbin will not fill evenly.
On most Singer machines, push the bobbin winder wheel or spindle away from the machine — it should click or snap into place. On some older models, you may need to flip a small lever or turn a dial. Once the bobbin winder is engaged, the needle will not move when you turn the hand wheel or press the foot pedal.
Wind thread onto the bobbin
Place an empty bobbin onto the bobbin winder post. Pull thread from your top spool, wrap it around the bobbin two or three times by hand to anchor it, then press the foot pedal or turn the hand wheel to start winding. The machine will pull thread onto the bobbin automatically.
Keep light tension on the thread with your fingers as it winds — do not pull hard, just guide it gently. The bobbin will fill in a spiral pattern. Most Singer machines have a sensor that stops the winding automatically when the bobbin is full. If your machine does not have this feature, stop winding when the bobbin is nearly full but not bulging — overstuffed bobbins jam in the case.
Once the bobbin is full, cut the thread and remove the bobbin from the winder. You now have a wound bobbin ready to insert into the bobbin case.
Insert the bobbin into the bobbin case
The bobbin case is a small metal or plastic housing that sits directly below the needle plate. Raise the presser foot — this opens the bobbin case so you can insert the wound bobbin. On most Singer machines, you lift the bobbin case cover or slide it to the side to access the case itself.
Hold the wound bobbin with the thread tail facing toward you. Insert the bobbin into the case so it sits flat and does not wobble. The bobbin should slide in smoothly; if it does not, you may have the wrong size bobbin or the case may be damaged.
Once the bobbin is seated, pull the thread tail through the tension spring or slot in the bobbin case — this is usually a small metal loop or notch. The thread should fit snugly but not be forced. Close the bobbin case cover and lower the presser foot.
Thread the needle and test your setup
Before you sew, thread the top of the machine with thread from your main spool. Raise the presser foot, hold both the top thread and the bobbin thread tail, and turn the hand wheel toward you one full rotation. This brings the bobbin thread up through the needle plate so both threads are ready to sew.
Place a scrap of fabric under the presser foot and sew a few stitches. Look at the underside of the fabric — the stitches should be tight and even, with no loose loops or bunching. If the underside looks loose, the bobbin thread is too loose in the case. If the top looks loose, the top thread is not threaded correctly or the tension dial needs adjustment.
Troubleshoot if the bobbin is not working
If your stitches break, bunch, or look uneven after you insert the bobbin, check these things first. Make sure the bobbin is wound evenly and is not overstuffed — a lumpy bobbin will not feed smoothly. Verify that the bobbin is seated all the way in the case and that the thread tail is threaded through the tension spring.
If the bobbin still does not work, remove it and check the bobbin case for lint, dust, or thread bits. Use a small brush or a piece of lint-free cloth to clean inside the case, then reinsert the bobbin. If the case itself is bent or cracked, it may need to be replaced — contact Singer or a local repair shop for a replacement case.
Frequently Asked Questions
What size bobbin do I need for my Singer machine?
Singer makes several bobbin sizes. Check your machine's manual or look at the bobbin case — the size is usually printed on it. Class 15 and Class 66 are the most common sizes for home machines. Using the wrong size will cause the bobbin to sit loose in the case and create uneven stitches.
Can I use a plastic bobbin instead of a metal one?
Yes, most Singer machines accept both plastic and metal bobbins as long as they are the correct size for your machine. Plastic bobbins are lighter and less likely to rust, but metal bobbins last longer. Either type works the same way — the difference is durability, not performance.
Why does my bobbin thread keep breaking?
Bobbin thread breaks most often when the bobbin is wound too tightly, the case is dirty, or the thread is old and brittle. Wind new bobbins at a moderate speed, clean the bobbin case regularly, and use fresh thread. If breaking continues, the bobbin case may be damaged and need replacement.
How full should the bobbin be before I use it?
Wind the bobbin until it is full but not bulging. A full bobbin should have thread wound evenly from bottom to top with no gaps. If the bobbin is too full, it will jam in the case; if it is too empty, you will run out of thread in the middle of sewing and have to rewind.
Do I have to rewind the bobbin every time I change thread color?
Yes, if you want the bobbin thread to match or coordinate with your top thread, you need to wind a new bobbin. You can keep several wound bobbins in different colors on hand so you do not have to wind one every time you sew. Store them in a small container to keep them clean and organized.