Why Is My Sewing Machine Jamming?

A sewing machine jam is one of the most frustrating problems sewists experience. When the machine jams, thread can bunch up underneath the fabric and prevent the machine from stitching properly.

Fortunately, most sewing machine jams are caused by simple issues that can be fixed quickly.

Below are the most common causes of sewing machine jams and how to fix them.

Incorrect Threading

One of the most common causes of sewing machine jams is incorrect threading.

If the thread is not properly seated in the machine's tension system, the stitches will not form correctly and thread may collect underneath the fabric.

Fix

Remove the thread and rethread the entire machine carefully, making sure the thread passes through every guide.

Always thread the machine with the presser foot raised.

check out our threading guide HERE

Bobbin Inserted Incorrectly

A bobbin that is placed incorrectly can easily cause thread jams.

If the bobbin thread does not flow through the tension slot properly, the stitch will not form correctly.

Fix

Remove the bobbin and reinstall it following the correct thread direction.

Dull Needle

A dull or bent needle can cause the machine to skip stitches and jam.

Needles should be replaced regularly to ensure smooth stitching.

Fix

Install a new sewing machine needle and check that it is inserted correctly.

Need help picking the right needle? check out our needle guide HERE

Thread Tension Problems

Incorrect thread tension can also cause bunching underneath the fabric.

If the tension is too loose, thread loops can form and jam the machine.

Fix

Return the tension dial to the default setting and test stitches on scrap fabric.

Final Thoughts

Most sewing machine jams are caused by small setup mistakes such as threading problems or worn needles.

By checking the needle, bobbin, and threading path, you can usually fix the issue in just a few minutes and continue sewing smoothly.