Cleaning the Bobbin Case

Thread wax and dust easily collect around the notch in the tension spring on the bobbin case, resulting in an incorrect thread tension. Therefore, the bobbin case should be cleaned as necessary should tension problems arise.
When cleaning the bobbin case, use card stock or another type of paper of similar thickness and sturdiness in order to prevent pieces of paper tearing off and getting lodged in the bobbin case.

1. Follow steps 1 to 8 in “Cleaning the Race” to remove the bobbin case.

   Cleaning the Race

2. Using a piece of paper of adequate thickness and sturdiness, slide the paper between the tension plate base and the tension spring and also slide the paper behind the notch of the spring to remove any dirt or dust.

   
   1. Tension plate base
   2. Notch
   3. Paper (e.g. business card type)
   4. Tension spring

   Do not bend the tension spring. In addition, do not use anything other than recommended paper to clean the bobbin case.

3. Use the cleaning brush to remove any lint and dust from inside the bobbin case.

4. Replace the bobbin case and needle plate.