Laser Cutting and Fabrication Design Guidelines

Laser Cutting Process

A laser cuts metal by melting the material, and then using the assist gas, forces the molten material away from the cut. The laser beam head or torch is moved over the surface of the material using CNC motors. Repeatability is based on age and maintenance of the machine.

Edge Quality Concerns

  • The laser cut edge will be slightly angled away from the contour being cut. This is called the kerf of the cut.
  • The kerf is more pronounced the thicker the material. On 1/4″ thick steel, the kerf is approximately .004″.
  • The kerf creates a hole that is slightly tapered. The thicker the material the larger the impact.

Design Considerations

  • Laser’s can produce highly accurate, complex exterior contours.
  • Use to ramp up to higher speed production methods.
  • Laser cut plate can replace certain castings with lower overall cost and faster turnaround time.
  • Laser cutting will cause the contour to be case hardened on heat treatable materials. This may cause some difficulties if additional machining is required.

Tolerances

  • The tighter the tolerances of a part the more time and care needs to be taken to achieve those tolerances. The table shows guidelines for the cost conscious, standard commercial parts and specialized parts.
 CostStandardSpecial
Up to 16"+/-.015"+/-.010"+/-.002"
Over 16"+/-.030"+/-.015"+/-.005"