How to Repair a Rattling Bobbin on a Sewing Machine

Twist the hand wheel so the needle is in the up position. Remove the bobbin and, if your machine has a removable one, bobbin case. Either slide the metal or plastic plate back or flip down the plastic door.

Spray the shuttle or bobbin area with spray duster to remove all lint and dust. If there are any visible threads stuck in the shuttle, remove them with tweezers.

Dip a cotton swab in sewing machine oil and apply to the moving parts of the shuttle. Rub the cotton swab lightly over the areas that look like hinges. Only apply a small amount of oil so that the mechanisms are properly lubricated.

Check the way your bobbin is loaded. Every sewing machine requires you to load your bobbin with the thread spooling from a specific direction. Remove your bobbin from the case and reload it, making sure the thread is wound in the correct direction.

Replace plastic bobbins with metal one. Plastic bobbins are lightweight, causing them to rattle and not dispense the thread evenly. A metal bobbin will sit firmly in the bobbin case and spin evenly.

Rewind your bobbin. Often rattling is caused by a badly threaded bobbin. The thread may have been wound crooked around just a small part of the bobbin. Unwind some of the thread from your bobbin, or try a new one.

Adjust the bobbin tension. If your bobbin is still rattling after cleaning and replacing it, remove the bobbin and case again. Locate the tension screw inside the shuttle. It is normally on the right, but varies by machine. Turn the screw with a screwdriver counterclockwise to loosen the tension. Only turn the screw slightly and test the adjustment by sewing on a piece of scrap fabric.