In addition to
Originally Posted by
WIChix
If the 500 has been sewing well, and this is a new problem, I would look elsewhere for the answer. Is the thread old? Pull the spool and do a complete rethreading. Check the upper tension setting, and look to see if the thread is between the right discs. Is the needle inserted with the flat side facing the correct direction? Is it the same needle as before, or is this a new needle? Sometimes needles (eyes) are missed in finishing....
and
Originally Posted by
bkay
... but I think filing the hook is asking for problems that can't be fixed. It might mess up the timing.
...my thought would be cleaning the bobbin area very well. I had some problems with thread knots that ended up with the machine locked up, and were resolved with cleaning.
I followed this
youtube video. The 401 is basically the same as your 500. It doesn't cost much and doesn't take long and it might resolve your issue.
bkay
Are you holding the thread behind when you start sewing? Another way to start is to pull threads behind foot, place fabric under foot, hold end of threads with one hand (left) and rotate hand wheel to lower the needle into the fabric with your right hand, with needle in the fabric, lower presser foot and begin sewing.
On page 14 of
http://ismacs.net/singer_sewing_mach...ion-manual.pdf It gives some causes of breaking the upper thread. However, number 8 wouldn't apply if you start with needle in the fabric.
Another possibility is that that the thread is getting caught on something, like the notch on the spool of thread. There also could be burrs or dirt in the thread path. Is the needle plate smooth or has it been nicked? Is the tension assembly clean?
Hopefully something will help. Slant needle machines are nice to sew on.
Janey - Neat people never make the exciting discoveries I do.