Sewing & Pattern making Terms


In sewing, a “bobbin” refers to a small spool or reel that holds the lower thread in a sewing machine. It is an essential component of the machine’s bobbin system and plays a crucial role in creating stitches.

Here’s what you need to know about bobbins:

  1. Thread supply: The bobbin holds the thread that forms the underside of the stitches when sewing. It is usually filled with the same thread from the one used in the upper thread of the sewing machine. The two threads interlock to create a secure and balanced stitch.
  2. Bobbin winding: Before inserting the bobbin into the machine, it needs to be wound with thread. Most sewing machines have a built-in bobbin winding mechanism that allows you to wind thread evenly onto the bobbin. This ensures a consistent thread tension and smooth stitching.
  3. Insertion and positioning: Once the bobbin is wound, it is inserted into the bobbin case or bobbin compartment of the sewing machine. The bobbin case is usually located beneath the needle plate. The bobbin thread is then threaded through the machine’s threading path, guiding it to the needle area.
  4. Stitch formation: As you operate the sewing machine, the bobbin and upper thread work together to form stitches. The needle thread passes through the fabric from top to bottom, while the bobbin thread is drawn up from below, creating a lockstitch or other stitch types, depending on the machine settings.
  5. Tension adjustment: Proper tension adjustment is crucial for achieving balanced stitches. The tension of the bobbin thread can be adjusted using a tension screw or dial on the sewing machine. Balancing the tension between the upper and bobbin threads ensures that the stitches are even and neither thread is too loose or too tight.
  6. Bobbin types: Bobbins come in various sizes and types, depending on the sewing machine model. The most common types are Class 15 and Class 66 bobbins, which differ in size and design. It’s important to use the appropriate bobbin size and style recommended by the machine’s manufacturer.

Understanding the role of the bobbin is essential for seamstresses, as it directly affects the quality and appearance of the stitches. Proper bobbin winding, correct insertion, and tension adjustment contribute to achieving well-formed and balanced stitches during sewing.

By ensuring that the bobbin is correctly prepared and inserted in the machine, you can sew with confidence, creating professional-looking garments and projects.

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Melissa Villegas
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