Laser Q&A With Expert Jordan Buhagiar – Alfex CNC Australia Laser Division Manager

Q: WHAT ARE THE BENEFITS OF HAVING MORE LASER POWER?

A: Generally speaking, the more laser power you have the faster you can engrave or the thicker you can cut. Keep in mind that not all materials require a lot of power – if you are only engraving materials like anodised aluminium or cast acrylic you do not need much power however if you plan on predominantly using your laser to cut then you’ll need to consider a suitable power depending on your specific application.

 

Q: HOW DO I KNOW WHICH DPI SETTING TO USE?

A: As a general rule you will want to use a mid-to-high dpi for engraving text or other items with fine details, and a lower dpi for photographs or large block-style objects. Again this is a general rule and you should experiment with the different settings to understand the different results you can achieve. The higher the dpi the more dots the laser will mark (basically more details) however this also increases the overall marking time. A lower dpi will provide for faster marking times but is not suitable for all jobs. One thing to keep in mind is that the lower the dpi you use the more laser power will be required in order to achieve the same depth/darkness of mark.

 

(1)    If the wood has been sealed/lacquered you should be able to remove most or all of the residues with a damp cloth, however, if the wood is raw you may need to use some fine sandpaper to remove the residue – we recommend having some 220 grit sandpaper on hand in case you ever need it

(2)    Alternatively, you can be proactive and use a light to medium tack masking paper first and then engrave it into the wood, allowing the residue to settle on the mark instead of your part. Then after the job simply remove the mask to reveal your perfectly clean engraved design

For materials other than wood

(1)    You can try using Isopropyl Alcohol (IPA) to clean away any leftover residue

(2)    Another tip is to use the Bottom-Up engraving feature found in your print driver (a standard feature on Epilog Lasers). In standard top-down engraving, there can be a large amount of engraving debris generated and as that debris is pulled towards the exhaust ports at the rear of the machine, some of it will collect in the areas that have just been engraved. The Bottom-Up function reduces the amount of smoke and residue so that it is not dragged across freshly engraved marks.  This feature is particularly useful for two-ply engraving plastics where you are engraving through a colour like red/blue/green into white underneath.

Regardless of the material you are engraving it is also a critical factor to make sure you have sufficient extraction otherwise the smoke and residue will hang around and settle on your material instead of being immediately sucked away after engraving.