3-Thread Flatlock Narrow (RN)

Upper looper thread (blue) extends over the fabric edge towards the bottom.

  1. Reduce RN-thread tension (green).
  2. Increase UL-thread tension (blue).

Upper looper thread (blue) doesn't reach the fabric edge.

  1. Reduce UL-thread tension (blue).
  2. Increase RN-thread tension (green).

Lower looper thread (red) not straight along the fabric edge.

  1. Increase LL-thread tension (red).
  2. Reduce RN-thread tension (green).
  3. Reduce UL-thread tension (blue).

The seam puckers. Lower looper thread (red) too tight.

  1. Reduce LL-thread tension (red).

Needle thread (green) doesn't reach the fabric edge.

  1. Reduce RN-thread tension (green).
  2. Increase UL-thread tension (blue).
  3. Increase LL-thread tension (red).

Needle thread (green) extends over the fabric edge to the top.

  1. Reduce UL-thread tension (blue).
  2. Increase RN-thread tension (green).

The fabric edge forms a tunnel or curls.

  1. Reduce RN-thread tension (green).
  2. Reduce UL-thread tension (blue).
  3. Increase the mtc micro thread control.
  4. Reduce the cutting width CW.
  5. Check the rolled hem selection N/R position.