Hello Ruth,
Those Apollo bobbin cases were a pain in the backside, if you have the black bobbin case you should not have any problems, however, look at the bobbin case and move it to the left with you left thumb and look at the gap between the bobbin case and the silver guide, you should have enough room for the thread to pass through taking into account that you would not use a thread thicker than a number 40, remember that singer machines were made to take Sylko and Trylko thread or a perfect mercerised thread number 40, 50, or 60.
If the gap is too wide between the bobbin case and the guide you can slacken the screw off that is on the guide and adjust it slightly, before you do that have a check of the bobbin case to make sure there is no damage on it, even the slightest nick will cause problems, if you have any problems e-mail me at the address below because I don't go back to the questions to see if anyone has left answers there.
Ken
drivewithken@blueyonder.co.uk
September 2007
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