Bernette Airlock b64 - 2-Thread Rolled Hem

Sewing test
68
2020-09 EN 5040064.00A.04
2-thread rolled hem
With a balanced stitch formation, the looper thread (red) loops around the cutting edge. The Needle Thread
(green) is identifiable on the right side of the stitch as a straight line and on the wrong side of the stitch as
points.
Stitch pattern Solution
The Looper Thread is too loose around the
fabric edge.
> Increase the Lower Looper Thread Tension
(red).
The Looper Thread is too tight around the
fabric edge.
> Reduce the Lower Looper Thread Tension (red).
> Reduce the Cutting Width «CW».
The fabric edge doesn't curl as intended.
> Increase the Cutting Width «CW».
> Elongate the Stitch Length «SL».
> Increase the Lower Looper Thread Tension
(red).
The Needle Thread forms loops on the wrong
side of the fabric.
> Increase the Right Needle Thread Tension
(green).
The seam puckers.
> Reduce the Right Needle Thread Tension
(green).
> Set the Differential Feed between 1 and 0.6
(Stretching).
> Shorten the Stitch Length «SL».
Tab.6: Optimizing the stitch: 2-thread rolled hem