Page "Hot-wire foam cutter" Paragraph 22

Cutting speed and wire temperature combine to determine the thickness and consistency of kerf.

For a given wire temperature, an attempted motion in excess of the wire's ability to melt the foam can lead to wire drag and poor surface finish of the cut foam.

Conversely, dwelling in the foam any longer than strictly required to melt the cut path can lead to excessively thick kerf.

A nonuniform feed rate can lead to a kerf of varying thickness.