Metal Polishing; Plastic Marking - Epilog Fusion M2 32 Manual

SECTION 14: MATERIAL ENGRAVING TECHNIQUES
We find for the best deep metal etching, moderate speed settings (20-30%) and more passes slowly chip away at the
metal for a better mark. Deep metal engraving requires maximum wattage. For these applications, a 30 or 50-watt fiber
laser is recommended.
Frequency is generally set between the 1-5% range. A lower frequency range provides more bursts of laser power per
pulse and is crucial to ablating the metal. We've found that focusing "into" the metal by .010" to .030" (.254 to .762
mm) helps in the removal of metal. No technical data is available on whether refocusing after each pass is helpful or
not. To better assist in removing metal cleanly, higher resolution (1200 DPI) with more overlap of laser pulses tends to
provide a cleaner, more defined etch.
Deep engraving will require multiple passes, which can be easily accomplished by changing the number of copies in the
print dialogue box for CorelDRAW. As with all materials including metals, the hardness or grade will ultimately determine
what settings and how many passes are needed to achieve a certain depth. Use the guidelines above as starting points
and experiment for best results.

Metal Polishing

Polishing of metals is accomplished by quickly heating up the metal's surface, changing its color, resulting in a
mirror-like finish. Polishing can be done on just about any metal including, but not limited to, raw alloys, heat-
treated metals, plated metals and precious metals.
For a high-contrast mark, polishing is best done on darker, matte finish metals. Cleaning the surface prior to processing
is recommended as oils, grease and other chemicals can affect the consistency and finish of the final marks. Dialing in the
settings for a polished mark is the most difficult of the three most popular metal marking techniques. Speed, power and
frequency play the biggest role.
• Speed is generally set on the high side, 50-100%, depending on wattage.
• The power is set in the 30-60% range, depending on wattage.
• Frequency is also set on the higher side, typically around the 50-100% range. A higher frequency setting equates
to less power per laser pulse. Too strong of a laser pulse and the laser beam starts penetrating the metal instead of
polishing, resulting in a dull or browning effect.
Focus should be set at zero. Printing resolution is in the range of 300 to 600 DPI but is mostly done at 400 or 600.
Start by determining your base speed, frequency and resolution setting. From there, select a power setting and start fine
tuning by adjusting the power in 1% increments or decrements.

Plastic Marking

The term "plastics" is commonly used to describe various grades and types of polymers. To keep things simple,
we'll refer to all polymers as plastic. There are many plastics that are compatible with the fiber laser's 1062 nm
wavelength of light. We refer to these as "engineered plastics" because many were designed to be laser-etched
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Fiber Laser Materials/Techniques