Choosing the right bobbin for your sewing machine
A bobbin holds the lower thread and works with the upper thread to form each stitch. Using the correct bobbin helps keep tension even and stitching smooth, and helps prevent thread jams and skipped stitches. Check your machine manual for the required bobbin class or part number
- Use plastic bobbins in machines with a top drop-in system and thread sensors.
- Metal bobbins are for machines designed for them.
- Keep several wound bobbins ready for large projects.
- Replace bobbins that are cracked, bent or warped.
Types of bobbins
- Plastic bobbins: lightweight and clear, so you can see the thread level.
- Metal bobbins: stronger, for machines designed to use them.
- Pre-wound bobbins: ready to use and convenient for embroidery and long projects.
- Bobbin cases: hold the bobbin and control bottom tension.
Bobbin classes explained
SINGER® machines use bobbin classes such as Class 15, Class 15J and Class 66. They look similar but are not interchangeable, so use the class your manual lists. A Class 15 bobbin is flat on the top and bottom, while a Class 15J has a slight curve and is a little shorter. Most modern PFAFF® machines use one clear plastic bobbin (part #820921096). HUSQVARNA® VIKING® bobbins are green, which marks them as genuine.
How to wind a bobbin
Follow the thread guides on your machine and wind evenly. A well-wound bobbin is firm and smooth, not loose or lumpy. Wind several in the colors you use most before a big project, so you do not have to stop and rewind.
Bobbin problems and fixes
- Uneven stitches: rewind the bobbin more evenly or check the tension.
- Thread nesting under the fabric: rethread the upper thread and check the bobbin is seated correctly.
- Thread sensor errors: check that you are using a clear plastic bobbin of the right type.
- Noise: clean lint from the bobbin area.
Why genuine bobbins matter
Genuine bobbins are made to your machine's exact specifications. Off-brand or wrong-size bobbins can cause tension problems, skipped stitches and wear on the bobbin case.
Colors and packs
Bobbins come in multipacks, pre-wound packs and colors. Color-coded bobbins help you organize thread by project or color.
Browse bobbin cases, bobbin winders, needles and thread to keep your machine running smoothly.