Custom CNC Laser Engraving Glass
CNCROi.com got a new fridge in the shop recently and with glass shelving, an opportunity to illustrate what’s possible using our Austrian industrial CNC laser opened-up!
Before we begin, note that there is nothing particularly special about this glass, we don’t know the grade or anything about where it was produced. This is not specialty glass made for lasers at all… just some random piece that came with the fridge!
Generally you can tell that a piece of glass was “laser processed” as you see the lines going across it. In this case, our goal was to match what you’d achieve using an industrial sand blaster (which we also have in the shop). The masking serves two purposes, it keeps the shatters in place and protects the glass from scratches during handling.
After the glass was masked, it was time to laser engrave it, this was done using a variety of power settings and passes as again, we wanted to make sure there were none of those “typical” laser lines produced, just an even and consistent frosting!
The black you see comes from the paper masking being vaporized, not the glass itself becoming black which is an entirely different process not outlined in this blog post though completely possible.
As the laser works its way down the mask, its shattering the upper layer of the glass from the heat generated by our industrial wide-format Trotec laser.
Unlike an industrial sand blaster, for flat work, the laser does a better job with the proper settings because we don’t have to deal with under spray, which is what happens when the masking raises-up due to the compressed air involved with sand blasting and frosting areas that you don’t want engraved.
In this case, the extremely fine points in the palm tree leaves is precise and absolutely crisp, something that would be exceedingly difficult using an industrial sand blaster, especially if the job was across several units.
Generally, cheaper glass produces better results due to its higher lead content than more expensive glass, our Trotec Speedy 400 flexx has no trouble harnessing the power of the photons to shatter the glass.
This does bring-up a common question we have, regarding wine bottles. Do you need to empty the bottle before laser engraving the bottle? No. The reason being is that the beam of energy is highly focused at the very top of the surface, the heat never goes to any depth, so your wine bottle is safe in a laser.
Additionally, CNCROi.com also has a rotary system so we can engrave AROUND a wine bottle as well, but when it comes to uneven surfaces or odd shapes and sizes, our industrial sand blaster comes into being. The shards that come off the final piece are incredibly small but care is still taken, nothing worse than having a microscopic shard of glass under a fingernail which you have no way of removing!
After a few passes, the black above is replaced with shattered glass below.
Although this looks great, it does require some clean-up as this shattered laser engraved glass will fall off, there is nothing holding it there other than the glass underneath. On something with this level of detail, the clean-up process can be extensive as the shards don’t always just fall off but must be motivated.
You can see a little of the shattered glass came off already in the bottom right of the image below, right at the edge of the “.com” and “cutting”.
As the laser engraved glass pane is moved more, the shattering becomes more apparent, you can see more of it around the “a” in engraving and there is still a little masking left around the palm tree leaves as well. All of this is removed during clean-up.
One last look before clean-up. This glass is engraved with a little depth so when you run your finger over it, you feel edges between what was laser engraved and what wasn’t.
After clean-up you can still clearly see the frosting we achieved, there is a little more shattered glass to be removed but the results produced here are permanent and will not fade, crack (unless the glass breaks) or peel off unlike some vinyl printing solutions.
The reflectivity is also not affected, again, a few very small shards remain in the bottom of the palm tree leaves but that’s easily removed with additional cleaning. It’s also possible to paint fill the glass because the paint will adhere to the shattered surface more than the smooth surface that wasn’t engraved by our CNC laser.
Looking at the engraving we did with our industrial laser, you can clearly see there are no lines anywhere, the results are crisp and sharp.
Regarding applications using glass, it ranges from custom corporate awards (which we can design and fabricate) to architectural elements. Glass is also a good material for use outdoors (where acrylic fails over time) and for harsher environments. We can engrave a variety of glass types, from glass blocks to tile as well, so you are not limited to anything flat or standard at the CNCROi.com shop.
Generally, for most applications, we end-up using acrylic as it’s less prone to break which is important in public areas and produces a similar result in a fraction of the time. The added advantage of acrylic over glass is that it’s available in a variety of shades and transparencies.
Looking for some awesome laser engraving on your glass? Contact CNCROi.com today!
