First thing to try is a brand new needle. A bent/damaged needle may not be able to pick up the bobbin thread.
Otherwise, it is possible it has a timing issue, ie the needle is arriving at the bobbin at the wrong time in order to connect with the bobbin thread. Search the internet web sites and videos. There is a lot of information on how to fix sewing machine timing. Or take it for service.
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First thing to try is a brand new needle. A bent/damaged needle may not be able to pick up the bobbin thread.
Otherwise, it is possible it has a timing issue, ie the needle is arriving at the bobbin at the wrong time in order to connect with the bobbin thread. Search the internet web sites and videos. There is a lot of information on how to fix sewing machine timing. Or take it for service.
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