SINGER W1044 - Manual (Page 15)

17. CLEANING THE SHUTTLE RACE
When the thread is tangled in the race or lint gets into the
space, between the shuttle and shuttle-race, this will cause
abrupt heavy running or complete stoppage of the machine.
When this occurs
1. Raise the needle bar to its highest position and take the
bobbin case out.
Fig 20
2. Pull the KNOBS (A) on both side of shuttle race (Fig. 20
& 21) aside, then take out the outside ring and the shuttle
body with your fingers.
3. After shuttle race and bobbin case have been cleaned, put
all of them back in reverse order.
Fig21
1 4 -