Hello Alison,
The bobbin case should not move at all, there are two screws on the spring clip at the right hand side of the bobbin case, slacken the screws and move the clip towards the bobbin case so there is only enough gap between the bobbin case and the clip for thread to pass through, if the machine sews okay you will need to keep adjusting that clip, if the machine does not sew okay then you may need to retime the machine, I can attach timing instructions if you email me but you will have to get my email address from any answer from page 25 down because this site no longer allows emaiul addresses to be shown.
Ken
drivewithken
March 2009
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