Custom Infill Tool Options

When you set the Infill Type to be Custom, the following options are available to control the infill:

Pattern Choose a Square Grid pattern or Rectangular Grid pattern
Sizing Options
Scale to Fit When you choose this option, you enter a length for scaling the selected custom infill shape. This allows you to increase or decrease the size of the custom shape. The option is Off by default, which uses the custom shape as-is.
Thickness Sets the infill wall thickness
Fill Options
Fill Shape The selected shape will be filled with material leaving voids between the shapes.
Fill Spaces The space between the shapes will be filled leaving a void in the interior of the selected shape.