The first few stitches are just fine but then the machine seems to seize up and stops. When I try to remove the fabric I can barely lift it and then I must cut through a veritable bird's nest of threads on the underneath side of the fabric. The bobbin is loaded correctly and the bobbin tension seems fine. The top thread is also loaded correctly. The feed dogs are up and the needle down. I'm not sure what else to try
Sewing Machines - PfaFF
Answers & Comments
You may have a jam under the needle plate. Take it off and have a look.
It is often a simple case of one of the threads not passing through the tension discs correctly. Try re-threading upper and lower, making sure the presser foot is up at the time.
Are you sewing a fine material? Sometimes fine fabric gets pushed down through the universal needle plate hole which is slightly elongated. If this is the case you need a straight stitch needle plate. You cannot do zig zig or anything other than straight stitch with this plate.
If re-threading does not do it and you do have a soft fabric, try popping some freezer paper or similar under the first few centimeters of sewing before buying another needle plate, it might work.