If by "threading," you mean the needle is not picking up the bobbin thread, the first thing to do is install a brand new needle. If the needle is damaged/bent, sometimes it will not connect properly with the bobbin thread.
If it is still not picking up the thread, then most likely there is a needle/hook timing issue when the needle arrives at the bobbin thread at the wrong time in order to make the connection. There are many web sites and videos on the internet that provide instructions on how to correct the timing. Otherwise, you could take it for service.
Answers & Comments
Here is a manual for your machine (if you need one):
https://www.sewshop.com/1007_Singer_Instruction_Manual___pdf_format_-8-4055-5653.html
If by "threading," you mean the needle is not picking up the bobbin thread, the first thing to do is install a brand new needle. If the needle is damaged/bent, sometimes it will not connect properly with the bobbin thread.
If it is still not picking up the thread, then most likely there is a needle/hook timing issue when the needle arrives at the bobbin thread at the wrong time in order to make the connection. There are many web sites and videos on the internet that provide instructions on how to correct the timing. Otherwise, you could take it for service.
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