What is the final step when threading a properly wound bobbin?

The final step when threading a properly wound bobbin is to pull the thread under the tension spring. This step is essential because the tension spring regulates the amount of tension on the thread as it unwinds from the bobbin during sewing. Proper tension is crucial for achieving even stitches and preventing issues like thread breakage or uneven stitch formation. By ensuring the thread is correctly positioned under the tension spring, you set up the sewing machine to operate smoothly.

While inserting the thread into the needle eye, cutting the thread after it has passed the delivery eye, and wrapping the thread around the presser foot are important steps in the overall threading process, they do not specifically relate to finalizing the setup of the bobbin. It's important to prioritize the correct placement of the thread under the tension spring to ensure proper machine operation.