Best Laser Technology for Engraving Paint on Backlit Display Panels?

[FONT=&quot]What is the best laser technology to engrave paint? CO2 or Fiber? I'm a machinist and do prototype and design work but I have never used a laser. A while back I made some display panels for a customer like show in the picture below. I outsourced the laser work. Was hoping for a big order but only ended up doing the prototyping. The panel is backlit and is made from acrylic that has been painted white, then black, and finally laser engraving to expose the white.
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[FONT=&quot]From what I have read Fiber is not suitable for acrylic but I don't actually need to engrave acrylic, just the black paint to expose the white paint layer. I hear Galvo units are much faster but how does the quality of the engraved area compare? I'm looking at doing about 500 panels a year similar to the one in the picture. Overall size will be around 3" x 6" (engraved area will be less). I'm a one man shop.
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[FONT=&quot]Should I go fiber or CO2? Glavo or gantry type? What wattage? Is fiber vs CO2, galvo vs gantry going to be easier to control engraving depth? Need to burn through the top layer of black paint but not the bottom layer of white paint. Engraved appearance is VERY important - clean crisp borders of engraved area and even engraved area without evidence of individual beam lines. Laser cost is more important right now than speed. Will a glass tube CO2 stepper motor machine give me good looking results if I take the time to dial everything in? If things work out I can always get a faster laser but if the quality of the engraving isn't top notch there wont be a next time. The guy I outsourced laser work to last time did a great job but I would like to bring the laser work in house.
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[FONT=&quot]If you have a machine for sale that would fit my need feel free to PM me.

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Fiber would possibly have an advantage here because it can go through the acrylic without damaging it, giving you a higher power window. I've seen the engraving from a stepper driven CO2 laser and honestly wasn't impressed. The bigger issue is unless it's made specifically for engraving, the power supply can't turn it's 25,000+ volt power supply on and off fast enough to produce sharp lines in the direction of travel. And without closed loop beam power regulation the engraving power can drift.

I'm almost thinking a laser diode would make the most sense here. I don't see high powers being particularly advantageous, unless you have the money for a very fast galvo machine.

I would say the choice of paint matters more than the laser, within reason. Say for the white paint you use a clear base that the laser can simply shine straight through, preferably a durable epoxy that can withstand higher temperatures. (Be aware epoxy paints may have poor UV stability). Then use a titanium dioxide pigment, which is very highly reflective, such that the beam scatters or diffuses through, but is only absorbed negligibly. I'm not sure what base should be used on the black paint.

Honestly I wouldn't think it could be done as cleanly as the parts you have, so the best I can say is I haven't seen any hobby price machines that can do it.

In the immediate before time (Jan of 2020) I bought a fiber galvo laser. 30W I think. $6K. Quite fast. Directly engraves metals (what I wanted forever but didn't want to pay $30K for.) Working area is 100mm square (maybe 100mm square) - so you can only do small areas.

I have no idea at all what it would do to paint though. And if the markings that need to be aligned are bigger than about 4" square you could have issues.

I have a dual head 130 watt china laser used for marking. I've learned a considerable amount about the small CO2 lasers, but only worked with a few processes because it's just for marking my parts.

I would say the speed, resolution and quality of the china lasers would surprise most everyone who hasn't used one.

What sucks is the user interface they come with.

I bought mine used. I hated the control/software. I researched. I bought the latest greatest Ruida 4 axis controller for $300 that is compatible with the user friendly Lightburn software that costs $100. Everything plugs in. Ruida actually has excellent support and Lightburn has a great forum.

I had four of these chinese dual head laser cutters. They ran production engraving jobs for 4 years with decent up time. 8 hours a day use and out of 8 laser tubes 4 were replaced at $700 a piece in that timeframe. They made millions of dollars in inventory. I sold off 3 of those lasers and all three are in use in industrial environments. 2 are cutting and marking acrylic sneeze guards and one actually cuts pieces for high end apparel items. The company that owned the lasers before I did upgraded because they were too troublesome to setup and use, especially for minimum wage employees. They bought European machines that were in the same class as Epilog. Can't remember the name, but they were around $45k each.

IMO, the China CO2 lasers are hard to beat. At first they seem confusing, but they aren't. Took a long time for me to figure out that "China laser" is the make, model, brand and serial number of every one of these regardless of what color it is. They all use the same parts. You have to think of it as being just like a printer or a fax machine, not an industrial machine.