Use the ZigZag Width to set the width of Horizontal ZigZag, Rotational ZigZag and Calligraphy.
Enter the desired width directly in the box before selecting Horizontal ZigZag, Rotational ZigZag or Calligraphy. Alternatively, use the up and down buttons to change the width at any time. Set the width from 0.1mm to 9.0mm in 0.1mm steps. The minimum and maximum width is set in Stitches Preferences 
. Use this to prevent zigzag stitches from getting too narrow or too wide for the section you wish to draw. For example, limit the width when drawing tapered shapes so they have a uniform appearance.
Use Z (narrower) and X (wider) while drawing zigzag stitches to dynamically change the zigzag width. Tap the Z or X key to change the width by 0.1mm. Hold the Z or X key to continuously change the width.
When the ZigZag Width is set to a very low value, usually 0.5mm or less, the stitch points may be placed so close together that the 3D view does not display the stitches correctly. When this happens, the stitches appear to be broken up. Use 2D view to verify that your stitches have been created as desired.