Glass is an amazing material. The naturally occurring ingredients to make it are abundant throughout nature (sand, soda ash, and limestone). Not only are the ingredients abundant, but the glass itself is 100% recyclable, and there is no loss in quality or purity regardless of how many times it is recycled. So as far as materials go, it is one of the most abundant sustainable commodities available to use in your laser system. CO2 laser glass etching creates some of the most elegant results imaginable.
Although a CO2 laser can’t cut glass, it can etch and mark with impressive results. The CO2 laser creates micro-cracks in the glass creating a white, “frosted” look on laser engravings that are highly detailed and clean. You aren’t just limited to sheets of glass, either. With amazing features like the 3D Camera along with the Rotary (and Riser on the Muse Core and 3D Autofocus), you can create elegant CO2 laser glass etching on things such as wine and champagne glasses. You can even etch on a full bottle of wine!
Glass Properties
Glass comes primarily from silica (sand), along with some other minerals, melted together to create glass with different colors and characteristics. The way the laser reacts to glass is much different than most other materials, as the laser is not removing material but creating heat reactions that expand the material creating microfractures on the surface of the glass.
Many types of glass use metal (such as leaded crystal). These metals can cause the laser to not mark the glass at all. For laser cutters, less expensive common glass (soda ash glass) works best. This includes most consumer glass such as your average bottle or glassware. CO2 laser glass etching on less expensive glass (such as items you can find at a dollar store), will have better results due to their lower metal content.
CO2 Laser Glass Etching: Applications
Soda-ash glass is the most common type of glass, making up nearly 90% of consumer glass products which includes the following:
- Flat Glass: Also called plate glass or sheet glass, commonly used for windows.
- Glassware: Great for laser marking, glassware includes drinking glasses, beer mugs, wine/champagne glasses, shot glasses, and more.
- Pressed/Molded Glass: A process of pressing molten glass into molds.
Please note: Leaded crystal glass or other high-end glass with heavy metal content will not be suitable for CO2 laser glass etching.
Etching glass turns a normal piece of glassware into a special showcase piece that can commemorate any occasion. Add logos, names, promotions, celebratory dates, graphics and custom designs to glassware, bottles, jars, mirrors and more. There is always a high-demand for custom glass etching, and the return on investment can be rather high, especially if you have customers who supply their own materials.
CO2 Laser Glass Etching: Considerations
In your laser engraver, glass will behave differently than other materials and each piece of glass can have a slightly different reaction to a CO2 laser. It is always best to have extra glass material on hand to dial in your settings. Bottles and glasses are popular items to laser engrave, but their roundness creates uneven focusing. For these, riser and rotary attachments are ideal as they keep the laser focused at one length the entire job. Since your CO2 laser glass etching is accomplished by creating microfractures in the glass, there is always a small chance that the glass may break as your laser etches the surface. Make sure to take all the proper safety precautions and never leave the laser unattended during the etching process.
Please note: It may be tempting to run your thumb or finger across the freshly etched glass. Do not touch the etching until after you have cleaned it first so you can avoid getting any glass splinters in your skin. Cleaning can be done by running the glass under lukewarm water and using a soft brush like a toothbrush. Just wait until the glass is completely cooled down before putting it under the water.
CO2 Laser Glass Etching: Approach
Testing your laser etching power setting on glass is critical since the outcome is sensitive and has a smaller window for success than regular materials. The power settings are going to be where you make the most fine tuned adjustments. You’ll want the most frosted look without the microfractures breaking loose from the main piece of glass.
If you need to refine your results, and the CO2 Laser is not giving you the fine results that you need, consider using a UV laser instead. A UV Laser system like the Muse UV Open Galvo, will produce finer and more consistent results.
Finishing Tips:
- Removing Debris: Use a small brush, like a toothbrush or stiff bristled paint brush, to remove any glass shards that are clinging to the surface of the glass.
- Cleaning: Use a small amount of rubbing alcohol or isopropyl alcohol with a paper towel to clean any oils or smudges.
- Adding Color: The frosted look can sometimes hide details in the engraving. There are paints that work well in filling in the gaps of the engraving and then easily wipe away the excess top layer. “Rub’n Buff” is a brand of wax metallic finish that you can apply to the engraving, then buff it out to get a nice metallic fill like gold or silver.
Wrap up:
There is a lot of potential when it comes to CO2 laser glass etching. Combined with a rotary tool, the options are nearly endless. So whether you are looking to add a little flare to your own projects, or if you are producing high quality gifts and materials to sell, a CO2 Laser will expand your capabilities. And if you want to take it to the next level, consider the Muse UV Open Galvo system with the 5W source.
Full Spectrum Laser is a leader in laser cutting and laser engraving systems. Our systems range in size from desktop units and high-volume machines through industrial-grade production equipment. Our machines are running all over the world: from grade schools to National Labs, garage startups and many Fortune 500 companies. Contact us today to learn more.