I have a Universal ILS 1275, great laser, but I'm having problems with certain media. When I engrave materials that reveal to black, I can't get the black any darker than a dull grey, which is causing some major headaches.
Laser details:
Universal Laser Systems ILS 1275, 48" x 24", 50w CO2, external air assist. Less than one year old, awesome piece of equipment.
Material details:
Problems are arising mainly with Gravograph Gravoply, several different top colors, but all revealing to black. Also Rowmark brushed aluminium reveal to black.
Before you say it, switching materials is NOT an option... these materials & colours are specified by my Enormous State University client, and are non-negotiable.
Problem specifics:
After engraving & cleaning off the dust & residue, the revealed black portions quickly fade to a dull grey colour, rather than a sharp, crisp black. Polishing/wiping/washing with various chemicals, potions & unguents helps, but only temporarily. Eventually, it always fades back to grey.
Process details:
I've tried many, many, many different parameter settings on the laser, trying to find the happy combination that gets that perfect cut. I've managed to dial in some damn good recipes for most of my materials, but this black issue is blowing my mind. Also, don't know if it's relevant, but the Gravo in particular seems to have a much thicker top layer than the Rowmark, and I have to make two passes in order to get through it without heating the plastic so much that it warps & melts. The Rowmark engraves just fine on a single pass, either lightly etched to just below the surface layer, or much deeper to give a heavier relief effect. At any rate, I'm definitely getting through to the solid black underneath.
Cleaning details:
Firstly, I never (after a few nasty surprises) use any alcohol on my laser media, so THAT's not the problem. At present, my cleaning consists of a soft, dry brush to remove most of the dust, followed by a spray of citrus cleaner & a vigourous toothbrushing to get the dust out of the edges. Since the citrus crap (which is great, don't get me wrong) leaves kind of an oily residue, the final step is a quick wash with mild soap and water. The pieces come out looking great, the black engraving all dark & shiny as it should be, but after an hour or less, the black has gone grey.
I talked to a sales rep from Gravo yesterday, and asked if he had any suggestions, but the most he could offer was a list of laser settings in the Gravo catalogue (which is pretty effing useless to me, since they're all for a 35w laser, & mine's a 50w... if it was as simple as tweaking the parameters, doncha think I'd'a hit on that by now? I mean, I've tried lots of different settings...). The other thing he said to try was wiping the engraved piece down with WD-40 (!). 'Kay, I'm skeptical about that. Chemicals dry eventually, and won't it just fade to grey again, but maybe a little slower?
Conclusion:
Apologies for the long post, but I wanted to get as much info in here as possible, to help all you smartie-pantses out there come up with an answer. So what's it gonna be? Are my laser settings wrong? Is my cleaning technique killing the material? Is there some magic potion out there that'll remove laser dust & residue, while giving me the deep, deep black tones I so desire? Or am I just utterly f*ck*d like a duck?
I enthusiastically await reasoned and thoughtful responses. Hell, I'll even entertain hostile and childish ones if they offer a solution.
Thanks!
Laser details:
Universal Laser Systems ILS 1275, 48" x 24", 50w CO2, external air assist. Less than one year old, awesome piece of equipment.
Material details:
Problems are arising mainly with Gravograph Gravoply, several different top colors, but all revealing to black. Also Rowmark brushed aluminium reveal to black.
Before you say it, switching materials is NOT an option... these materials & colours are specified by my Enormous State University client, and are non-negotiable.
Problem specifics:
After engraving & cleaning off the dust & residue, the revealed black portions quickly fade to a dull grey colour, rather than a sharp, crisp black. Polishing/wiping/washing with various chemicals, potions & unguents helps, but only temporarily. Eventually, it always fades back to grey.
Process details:
I've tried many, many, many different parameter settings on the laser, trying to find the happy combination that gets that perfect cut. I've managed to dial in some damn good recipes for most of my materials, but this black issue is blowing my mind. Also, don't know if it's relevant, but the Gravo in particular seems to have a much thicker top layer than the Rowmark, and I have to make two passes in order to get through it without heating the plastic so much that it warps & melts. The Rowmark engraves just fine on a single pass, either lightly etched to just below the surface layer, or much deeper to give a heavier relief effect. At any rate, I'm definitely getting through to the solid black underneath.
Cleaning details:
Firstly, I never (after a few nasty surprises) use any alcohol on my laser media, so THAT's not the problem. At present, my cleaning consists of a soft, dry brush to remove most of the dust, followed by a spray of citrus cleaner & a vigourous toothbrushing to get the dust out of the edges. Since the citrus crap (which is great, don't get me wrong) leaves kind of an oily residue, the final step is a quick wash with mild soap and water. The pieces come out looking great, the black engraving all dark & shiny as it should be, but after an hour or less, the black has gone grey.
I talked to a sales rep from Gravo yesterday, and asked if he had any suggestions, but the most he could offer was a list of laser settings in the Gravo catalogue (which is pretty effing useless to me, since they're all for a 35w laser, & mine's a 50w... if it was as simple as tweaking the parameters, doncha think I'd'a hit on that by now? I mean, I've tried lots of different settings...). The other thing he said to try was wiping the engraved piece down with WD-40 (!). 'Kay, I'm skeptical about that. Chemicals dry eventually, and won't it just fade to grey again, but maybe a little slower?
Conclusion:
Apologies for the long post, but I wanted to get as much info in here as possible, to help all you smartie-pantses out there come up with an answer. So what's it gonna be? Are my laser settings wrong? Is my cleaning technique killing the material? Is there some magic potion out there that'll remove laser dust & residue, while giving me the deep, deep black tones I so desire? Or am I just utterly f*ck*d like a duck?
I enthusiastically await reasoned and thoughtful responses. Hell, I'll even entertain hostile and childish ones if they offer a solution.
Thanks!
