When winding a bobbin, what must you do before starting?

Before starting to wind a bobbin, it is essential to raise the presser feet and unthread the needle. This step is critical because the presser feet being lowered can cause the threading mechanism to interfere with the winding process. By raising the presser feet, you ensure that the tension on the thread is released, allowing for smooth winding without any obstruction. Additionally, unthreading the needle helps to prevent any additional strain or tangling in the thread during the winding process.

This preparation step is vital for achieving an evenly wound bobbin, which is necessary for proper sewing machine function. Having an evenly wound bobbin ensures that the thread feeds correctly and prevents issues such as snags or uneven stitches while sewing.