Bernette b79 - Troubleshooting

Attachment
139
2019-02 EN 5020079.00A.04
17.2 Troubleshooting
Failure Cause Repair
Uneven stitch formation
Upper thread too tight or too
loose.
> Adjust upper thread tension.
Needle blunt or bent. > Replace the needle, make sure that a new BERNINA
quality needle is used.
Poor quality needle. > Use a new BERNINA quality needle.
Poor quality thread. > Use quality thread.
Incorrect needle/thread
combination.
> Match the needle with the thread size.
Incorrectly threaded. > Rethread.
Fabric has been pulled. > Feed the fabric evenly.
Skipped stitches
Incorrect needle. > Use the needle system 130/705H.
Needle blunt or bent. > Replace the needle.
Poor quality needle. > Use a new BERNINA quality needle.
The needle is incorrectly inserted. > Insert the needle with the flat side to the back as far up
as it will go into the needle holder and tighten the
screw.
Incorrect needle point. > Match the needle point to the texture of the material.
Faulty stitching
Thread remnants between the
thread tension discs.
> Fold a piece of thin material and slide the folded edge
(not the raw edges) between the thread tension discs.
Incorrectly threaded. > Rethread.
Thread is caught in the hook. > Remove the upper thread and the bobbin case, turn the
handwheel backwards and forwards by hand and
remove the thread remnants.
Incorrect needle/thread
combination.
> Check the needle/thread combination.