Bernette b68 AIRLOCK - 2-Thread Overlock (LN) + Chainstitch (RC)

Sewing Test
86
2022-05 EN 50400685.00A.04
Stitch Formation Measures
Chainstitch needle thread (yellow)
forms loops on the bottom side of
the fabric.
> Increase RC-Thread tension (yellow).
> Reduce the CL Thread Tension (purple).
> Reduce the stitch length SL.
> Check threading path.
Chain looper (purple) thread loose
on the bottom side of fabric.
> Increase the CL Thread Tension (purple).
The fabric edge forms a tunnel or
curls.
> Reduce UL-thread tension (blue).
> Reduce LL-thread tension (red).
> Increase the mtc micro thread control.
> Reduce the cutting width CW.
> Check the rolled hem selection N/R position.
The seam puckers.
> Reduce RC-Thread tension (yellow).
> Reduce RN-thread tension (green).
> Reduce the CL Thread Tension (purple).
> Set the differential feed between 1 and 0.6 (stretching).
> Reduce the stitch length SL.
2-Thread Overlock (LN) + Chainstitch (RC)
Stitch Formation Measures
Lower looper thread (red) extends
over the fabric edge to the bottom.
> Reduce LN-Thread tension (green.
> Increase LL-thread tension (red).
> Reduce the cutting width CW.
Needle thread (green) doesn't reach
the fabric edge.
> Reduce LN-Thread tension (green.
> Reduce the cutting width CW.
> Increase LL-thread tension (red).
Lower looper thread (red) doesn't
reach the fabric edge.
> Reduce LL-thread tension (red).
> Increase LN-Thread tension (green).
> Reduce the cutting width CW.
Needle thread (green) extends over
the fabric edge to the top.
> Reduce LL-thread tension (red).
> Increase LN-Thread tension (green).
> Reduce the cutting width CW.
Chainstitch needle thread (yellow)
forms loops on the bottom side of
the fabric.
> Increase RC-Thread tension (yellow).
> Reduce the CL Thread Tension (purple).
> Reduce the stitch length SL.
> Check threading path.
Chain looper (purple) thread loose
on the bottom side of fabric.
> Increase the CL Thread Tension (purple).