Singer 4423CL Instruction Manual page 47

EN
Left and Right Side Balance for Buttonhole
Stitch density on right and left sides of buttonhole can be
adjusted by buttonhole balance control dial.
This dial should usually be in a neutral position (between "+"
and " ") –
If the stitches on the left side of buttonhole are too close
together, turn the dial to the left (+).
* Turning dial to the left opens left side.
If the stitches on the left side of the buttonhole are too open,
turn the dial to the right ( ). –
* Turning dial to right closes left side.
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