SINGER 15-91 - Manual (Page 14)

After threading, take the bobbin case b
3
^ the
latch, holding it between the thumb and forefinger
12
To Replace the Bobbin Case
F ig . 10. B obbi - x C. vse T hiie . a . ded and II eplaced
of the left hand. Place the bobbin case on the center
stud (B, Fig. 10) of the shuttle bodj^ with the posi­
tion finger (A, Fig. 10) opposite the notch at the top
of the shuttle race. Release the latch and press the
bobbin case back until the latch catches the groove
near the end of the stud. Allow about three inches
of thread to hang free from the bobbin case and
close the slide in the bed of the machine.