Epilog Laser LEGEND 24EX 6000, Owner'S Manual

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Section 10: Material Engraving Techniques
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The lacquer prevents the brass from oxidizing and the bright reflective surface will
stay bright for years.
Some manufacturers also sell painted brass that is solid brass, not brass coated steel.
If the brass is polished before the paint is applied you will have a nice reflective
engraved surface. If the brass is not polished, the result will be a dull, tarnished brass
that will require a secondary polishing process after laser engraving. This is time
consuming and most engravers do not want to spend the time and effort necessary to
turn this into an acceptable product.
Note - Always ask before lasering painted brass if you don’t know what the
substrate is!
If you are unsure if the piece that you have is brass-coated steel or brass, you can test
the material with a magnet. A magnet will stick readily to brass-coated steel, but
since solid brass is not magnetic, a magnet will fall helplessly away from solid brass.
Brass Engraving Techniques
Engrave painted brass at high speed and low power. It takes very little power to
remove the paint coating and too much power will melt the paint and distort the
image. If you are producing engraving that appears to be “fat” or has a balloon
appearance to it, you are probably using too much power. Reducing the power will
bring back the nice sharp images that are normally produced with painted brass.
Note - Use caution when trying to engrave brass coated pens. Many pens have a
very hard epoxy paint that is completely unacceptable for CO2 laser engraving.
You should only use pens that you have experimented with or that are specifically
designed for CO2 laser engraving. Be aware that there are many pens that can be
laser engraved with a YAG laser but these pens are usually not compatible with the
CO2 laser that you are using.
Some pens are “almost” CO2 laser engraveable. If you engrave through the paint and
there is a slight shadow remaining, try to clean the engraved area with EverBrite™ or
lacquer thinner. Depending on the paint, there is a good chance that the shadow will
disappear and an excellent engraving result achieved.
Use caution when trying to engrave blue painted brass. Blue paints contain very
aggressive pigments that penetrate the metal surface and it can be extremely difficult
to remove all of the blue color, but again, try EverBrite or lacquer thinner to remove
the shadow.