Bernette Airlock b64 - 2-Thread Flatlock; 2-Thread Overlock

Sewing test
69
2020-09 EN 5040064.00A.04
2-thread flatlock / 2-thread overlock
With a balanced stitch formation, the Lower Looper Thread (red) lies on the right side of the stitch from the
needle penetration point to the fabric edge.
The Needle Thread (yellow or green) forms a «V» on the wrong side of the stitch related to the insertion into
the fabric edge.
Stitch pattern Solution
The Lower Looper Thread overedges the
fabric edge towards the wrong side of the
fabric.
> Increase the Lower Looper Thread Tension
(red).
> Reduce the Needle Thread Tension (yellow or
green).
The lower looper thread doesn't reach to the
fabric edge.
> Reduce the Lower Looper Thread Tension (red).
> Increase the Needle Thread Tension (yellow or
green).
The Needle Thread doesn't reach to the fabric
edge.
> Increase the Lower Looper Thread Tension
(red).
> Reduce the Needle Thread Tension (yellow or
green).
The Lower Looper Thread overedges the
fabric edge towards the wrong side of the
fabric.
> Reduce the Lower Looper Thread Tension (red).
> Increase the Needle Thread Tension (yellow or
green).
The fabric edge forms a tunnel or curls.
> Increase the mtc Mircro Thread Control.
> Reduce the Cutting Width «CW».
> Shorten the Stitch Length «SL».
> Check the Rolled Hem Selection Lever position
«N».
Tab.7: Optimizing the stitch: 2-thread flatlock / 2-thread overlock