Thread breaks can occur from issues with the bobbin. To ensure that the bobbin is not the problem, look for the following issues when troubleshooting thread breaks.
- Wrong Type of Bobbin
- Bobbin Thread is Low or Out
- Bobbin is Overwound
- Bobbin Case Not Properly Inserted into the Machine
- Bobbin Tail Too Short
- Improper Bobbin Tension or Dirty Bobbin Case
- Damaged Bobbin Case
Wrong Type of Bobbin
The AMAYA uses a style L bobbin. Attempting to use a different style would be difficult and could produce many problems.
Using spun polyester bobbins can also cause some thread break issues. Spun polyester bobbins are created by spinning multiple polyester fibers together. This creates a fuzzier thread that pulls less smoothly through the system and generates a good deal more lint.
Use Style L continuous polyester filament bobbins.
Bobbin Thread is Low or Out
As bobbins unwind, the tension can become inconsistent. This can cause bobbin tension that is too loose or too tight. That can result in bobbin pulling through to the top of the design or thread breaks. It can also result in bobbin breaks.
Change to a new continuous filament polyester bobbin.
Bobbin is Overwound
Some pre-wound bobbins are overwound and become big enough to apply pressure to the bobbin case. This creates resistance as the bobbin attempts to spin. This resistance can mimic a bobbin tension that is too tight and produce thread breaks and misstarts.
Cast off bobbin thread before loading the bobbin into the bobbin case or try a new bobbin.
Bobbin Case Not Properly Inserted into the Machine
If the bobbin case is not inserted properly in the AMAYA, the machine cannot form a complete stitch. A loose bobbin case will rattle and can cause thread breaks and needle breaks.
If the bobbin case is not inserted at all, the machine cannot create a stitch. The thread will usually get caught on the central shaft of the rotary hook. You will also commonly hear a popping sound before the thread break.
Remove the bobbin case and insure that the rotary hook is clean. Clean the area with a brush or canned air. Then, with the pigtail in the twelve o'clock position and the bobbin facing the machine, insert the bobbin case into the rotary hook. If the lever on the case is not used, you can hear the bobbin case click into place. See how in the bobbin threading and tensioning section.
Bobbin Tail Too Short
If the thread breaks are occurring mostly as the machine is starting, the problem could be misstarts from the bobbin tail being too short when the bobbin case is inserted into the machine. Ideally, the bobbin tail should be two to three inches long. Longer tails can wrap up in the machine. Shorter tails may not allow for a stitch to catch when starting the machine.
When inserting the bobbin case into the machine, trim the tail to two to three inches in length.
Improper Bobbin Tension or Dirty Bobbin Case
Bobbin tension that is too tight can cause thread breaks, misstarts, puckering, and design registration issues.
Bobbin tension that is too loose can cause bobbin pull to the top of the design.
A dirty bobbin tension spring can mimic any of the problems above. If lint is caught under the tension spring and the spring is over-tightened to compensate, the tension spring may become damage and the case may need to be replaced.
Clean and properly tension the bobbin case. See how in the bobbin threading and tensioning section.
Damaged Bobbin Case
The bobbin case that holds the bobbin must maintain its original shape. If dropped, the bobbin case may have bent and is no longer round. This will apply uneven pressure on the bobbin and create uneven tension.
Replace the bobbin case with a new one. You can purchase one from www.shopmelco.com.