What Is Kerf? Laser and CNC Cutting Explained
Definition
Kerf is the width of material removed by a cutting process, such as a laser beam, saw blade or router bit. Because the cut follows the center of the design line, parts come out smaller and holes larger by the kerf width unless the path is offset.
Also called: kerf width, cut width, kerf offset.
Every cutting tool removes some material. On a laser, that strip is narrow, but on a press-fit joint it is the difference between snug and loose.
Compensating for kerf
Measure the kerf with a test cut, then either set a kerf offset in your laser software (half the kerf) or adjust the design. The kerf calculator does both, and laser kerf explained walks through the test.
Questions
What is a typical laser kerf?
On diode and CO2 lasers, usually 0.1 to 0.3 mm, depending on material, thickness, focus and power.
What is kerf offset?
A kerf offset moves the cutting path by half the kerf, outward on outer cuts and inward on holes, so parts come out at their drawn size.