D5 needles are specially designed for use with Fischbein portable bag closing machines mainly for the Model F.
- Broken or bent needles: This is the most obvious indicator. A damaged needle can not only snag and tear the material you’re sewing, but it can also damage the machine itself.
- Skipped stitches: If you’re noticing gaps in your stitch line, it could be due to a dull or burred needle that’s not piercing the fabric cleanly.
- Uneven stitches: Similar to skipped stitches, uneven stitches can be caused by a worn needle that’s not providing consistent tension.
- Excessive thread breakage: If your thread is breaking more frequently than usual, it could be due to a rough or damaged needle eyelet.
As a general rule, it’s a good idea to replace your D5 needles after sewing approximately 5,000 bags. However, the actual lifespan of your needles will depend on the materials you’re sewing, the frequency of use, and the overall condition of your machine. It’s always best to err on the side of caution and replace needles more often than not, especially if you’re noticing any of the problems mentioned above.
