Singer 99 Series - To Adjust the Bobbin Case Position Bracket

To Adjust the Bobbin Case Position Bracket
If for any reason it becomes necessary to adjust the bobbin case position
bracket to obtain the proper thread space between the bobbin case and the
bobbin case bracket, loosen the screw (E, Fig. 3) and move the bracket until
there is between .010 to .015 of an inch space at the heel of the bobbin case
and the cushion spring, then securely tighten the screw (E, Fig. 3).