Plastic - Epilog Laser Legend 6000 Owner's Manual

Owner's Manual for EPILOG Legend Model 6000
December, 2000

PLASTIC

PLASTIC BACKGROUND
Engraving plastics have changed greatly in the past few years. Before lasers, plastic manufacturers designed
plastic for rotary engraving systems. A rotary engraving system uses a mechanical spinning bit to remove
material. Therefore the depth of the top layer or "cap sheet" was designed to make it easy to rotary engrave.
Cap sheet thickness was approximately .010 inches thick and laser engraving was nearly impossible because
by the time you applied enough power to get through the cap sheet the laser melted and deformed the plastic.
Plastic manufacturers have developed a broad range of plastics that have thinner cap sheets that are .002 to
.003 inches thick that provide much better engraving and cutting characteristics. These plastics are commonly
referred to as Micro Laminates, Micosurfaced, or simply laser engravable plastics. These plastics are
generally very easy to engrave with a laser since they all have similar characteristics.
Because there is such a broad range of plastics it is necessary to experiment to determine if a particular type
of plastic is laser compatible. Different color plastics, even if they are from the same manufacturer will have
unique speed and power settings. Use the guidelines in this manual as a starting point when determining the
correct speed and power settings. If you do not get acceptable initial results with the recommended speed and
power settings start experimenting by first changing only the power setting. If adjusting the power setting
does not work, start over and adjust only the speed setting. Once you have acceptable results, record those
settings for that particular plastic so that you do not have to repeat the experimentation process.
PLASTIC ENGRAVING TECHNIQUES
Always remove the clear protective cover layer before engraving.
Once you have the correct speed and power settings you can improve your engraving results even more by
taking the focus lens out of focus (lower the table) by about 1/16 of an inch. This technique enlarges the
focus beam a little bit and provides more beam overlap on each pass of the laser. The greater overlap
produces a smoother engraved surface on the plastic and eliminates the grooves that you sometimes see when
engraving plastic.
With some plastics it is best to engrave using two passes. The first pass cuts through the cap layer and the
second pass cleans away the residue that some plastics leave behind.
Another technique that can be useful is to mask the plastic before engraving with transfer or masking tape.
This will prevent a buildup of residue on the plastic surface. Misting the transfer tape with water will reduce
heat buildup and melting on sensitive plastics.
54 Section 10 – Engraving Techniques