Once a week, I service my Featherweight. At that time, in addition to cleaning, oiling and lubricating the machine, I put in a new needle and wind bobbins with thread. I keep 8 filled white bobbins and 8 filled light tan bobbins. Since I use my Featherweight only for piecing, those colors usually work for me. If I know I will need other colors such as black, gray, or green, I wind them when servicing. I am left handed and threading the needle on a Featherweight is NOT my idea of fun. With the pre wound bobbins, I only thread my Featherweight once a week.