Ceramics have been used by humans for thousands of years to create both practical and decorative objects. With the advance of laser engraving technology, ceramics can now be personalized and decorated with detailed designs and patterns, enabling endless creative possibilities for makers, artists, as well as hobbyists.
In this blog, we will share everything you need to know to get started with laser engraving ceramics. We will explore the laser engraving on ceramics, including the types of ceramics suitable for laser engraving, the types of lasers used, and a step-by-step tutorial of processing ceramics with a visible blue laser using different methods including LaserPecker LP2.
Laser engraving ceramics is not easy, as it requires some procedures before and after engraving. Our goal is to help you navigate the learning curve and take your laser engraving skills to the next level.
Here is the outline of this blog:
1. A brief introduction to ceramics.
2. What types of ceramics are suitable for laser engraving?
3. What types of lasers are suitable for ceramics?
4. Step-by-step tutorial of processing ceramics with visible blue laser (with my product LP2)
4.1 Using black markers to paint the ceramic surface (not recommended after actual test)
4.2 Using Norton White Title Method (more complicated)
4.3 Using a black marking paper to cover the surface (recommended)
A brief introduction to ceramics
Ceramics refers to inorganic, nonmetallic materials made from clay and hardened by heating. Ceramics form when clay particles bond together during heating, a process known as sintering. Clays contain mineral fragments, carbonaceous materials, and metal oxides which fuse together to create glassy or crystalline ceramics.
Ceramics are typically durable and wear-resistant, making them ideal for use in various environments. Ceramics also have exceptional thermal stability, enabling them to endure high temperatures without deforming or breaking.
Additionally, they are chemically inert, meaning they do not react with most chemicals and are resistant to corrosion. These properties make ceramics suitable for use in various industries, including aerospace, automotive, electronics, and medical.
In our daily lives, ceramics are used in the form of pottery, tableware, and decorative items. They are also used in the construction industry as bricks, tiles, and pipes, providing strength and durability to buildings and infrastructure.
What types of ceramics are suitable for laser engraving?
The most suitable types of ceramics for laser engraving are those that have a high contrast between the surface and the underlying material. Some common types of ceramics that are suitable for laser engraving include porcelain, stoneware, and glazed ceramics.
(From left to right: Porcelain, Glazed ceramics and Stoneware. Source: Wiki)
For the best results, the ceramic material should have a smooth, non-porous surface. Stoneware, porcelain and glazed ceramics generally work better than raw earthenware or terra cotta. A consistent, fine-grained and minimally flawed composition is also important. Ceramic tiles, plates or bowls with simple geometric shapes tend to engrave more evenly than complex forms.
What types of lasers are suitable for ceramics?
Common ceramics like stoneware and porcelain are made primarily of clay minerals, feldspar, and quartz. These ceramics can be engraved using infrared lasers, especially fiber lasers and CO2 lasers with wavelengths of 10600 nm and 1064 nm, respectively. However, visible wavelength lasers, especially blue diode lasers around 445 nm, yield better results for ceramic engraving.
The shorter wavelength of blue lasers allows for finer detail and higher resolution engraving of ceramics. Blue lasers can achieve a beam diameter of around 0.07 mm, enabling extremely intricate designs. They also produce a narrower kerf, resulting in less fracturing of the ceramic surface during engraving. Blue lasers require less power to engrave ceramics compared with infrared lasers, typically 10-15 watts instead of 30 watts or more. This lower power means less heat is generated, reducing damage and cracking.
Step-by-step tutorial of processing ceramics with Blue Laser
While CO2 and fiber lasers are commonly used for ceramic engraving, their high cost makes them unsuitable for most hobbyists. A more affordable and practical option is a blue laser with a wavelength of around 450nm.
However, as we mentioned earlier, ceramics have high thermal stability and chemical inertness, making them highly durable but difficult to process without additional procedures. Also, many ceramic tiles or porcelain have a pale white color, making it easy to reflect the visible blue laser and hard to absorb the energy the laser creates.
To successfully engrave on a white ceramic surface using a blue light laser, it is necessary to use methods to cover the surface. After several tests, we have identified three methods for engraving on white ceramic using a blue light laser. We will use a white ceramic cup and the LaserPecker LP2 as an example to demonstrate two of those methods.
The Norton White Tile Method
Using a high-power CO₂ laser to engrave ceramic tiles can lead to a problem similar to that encountered when engraving glass. The laser creates the design by causing small cracks on the surface of the ceramic tile, which can compromise its integrity. Although the glazed surface of the tile is waterproof, the CO2 laser might remove material from this layer, causing the tile no longer to be completely waterproof. As a result, it is not suitable for use in areas where it may come into contact with moisture. To solve this problem, the Norton White Tile (NWT) method is introduced.
It is a little bit wrong to say “to engrave with NWT method”. This method is actually a laser marking process instead of engraving, which relies upon coating the white ceramic tile with Titanium Dioxide (TiO2) and using a laser to have a chemical reaction with the surface to leave the permeant marks.
However, when laser strikes the surface and causes the process of darkening the Titanium Dioxide, it can only create a black and white color. Therefore, it is recommended to engrave on white ceramic tile with a greyscale photo. And this method is called Dithering.
In dithering, the image is comprised of black and white dots. If you look at old newspaper photos using a microscope, you can see these dots.
The most important parameter of dithering is DPI, which stands for "Dots Per Inch." And this parameter can be influenced by spot size of laser. The smaller the spot size, the higher the DPI, and the higher quality of the photo. For example, a laser with a spot size of 0.05mm (the spot size of LaserPecker LP2), can achieve approximately higher than 282DPI, resulting in stunning and attractive images.
After all of this theoretical preparation. Now it’s time to get started:
The first step in engraving a ceramic tile is to prepare the surface. We recommend cleaning the ceramic tile with denatured alcohol, or acetone, or lacquer thinner to remove any oil or grease and ensure a clean surface for engraving.
The second step is to apply a layer of material containing Titanium Dioxide(TiO2) to the surface of the ceramic tile. While most white paint contains TiO2, we recommend using Rust-Oleum's Cold Galvanizing Compound or Rust-Oleum's 2X Gloss White for the best results. It is important to ensure that the surface is evenly coated, which can be achieved using a spray or roller. After painting, leave the tile outside to dry for 24 hours.
The third step is to prepare your design. You can create a grayscale image using any photo software, or you can upload your photo to the imag-R website (https://www.imag-r.com/), where you can resize and set the DPI parameters. The website also provides a material mode where you can choose the appropriate settings for the Norton White Tile.
Now, it’s strongly recommended to prepare some more tiles and run a power scale test to figure the proper setting for laser power and speed before any engraving. The final results depend on your type of tile, the paint you use, and the laser machine. Here is the recommended power scale test setting:
|Laser Power 20W||Laser Power 10W||Laser Power 5W|
Power setting 50%~100%
Power setting 50%~100%
Power setting 50%~100%
Speed 60mm/s to 130mm/s
Speed 15mm/s to 85mm/s
Speed 5mm/s to 20mm/s
After the preparation, it is time to begin engraving. The TiO2 in the white paint has two molecular structures: anatase and rutile. When laser engraving the ceramic surface with white paint containing TiO2, the laser heats the surface and causes the anatase to undergo a molecular structure reformation into rutile. Under the laser, the structure of rutile molecules gives a black color and permanently bonds together, while still retaining the features of waterproofing and scratch resistance.
(From anatase to rutile. Source: Wiki)
After you finish engraving, please remember to clean the surface with lacquer thinner or denatured alcohol.
Choose ceramic tiles with bright white color. Do not use any pale white appearance.
Make sure the tile is coated with equal thickness to achieve the best optimal outcome.
Try to have the white paint that has a high concentration of TiO2.
Using a black marker to paint the ceramic surface
If you don't have such tools like TiO2 white paint or denatured alcohol and want to engrave on everyday items, we recommend using the LaserPecker LP2. This portable and convenient laser machine can help you achieve your engraving goals with ease. The LaserPecker LP2, offers a 5-watt, 450nm blue light laser with an engraving speed of 6mm/s-600mm/s, high accuracy of 0.05mm, and maximum 2K resolution.
This method is the most cost effective and easy one. It only needs to cover the ceramic surface with a black marker. The blackr color helps to absorb the energy emitted from blue light laser and leaves marks on the surface.
However, choosing a suitable marker for this process can be a bit tricky. The marker should fully cover the surface with black color, but some markers, especially on curved surfaces, may leave white spaces after painting. When painting the cup, some markers would erase the black color and turn this area into white again and badly damage the final result. Here is a negative example of painting the cup, which should be avoided:
After painting the surface of the cup, assemble the LaserPecker LP2 by tightening two screws. One screw is used to stabilize the electric stand, while the other is used to secure the machine.
Connect the power cord to the machine, which is located on the right in the picture below. The machine's light will turn on if it is charged. Next, connect the wire between the machine and the electric stand, which is located in the middle of the picture, to provide power to the stand so that you can adjust its height.
Finally, since we will be engraving on a cylindrical cup, we will need the LP2 Electrical Roller. Connect the wire between the machine and the roller. Please note that the LaserPecker logo on the roller accessory should be facing the same direction as the logo on the engraving plate to ensure a consistent engraving direction.
Next, connect your LaserPecker app with the machine using Bluetooth. When you turn on the app, Bluetooth will search for the device and connect automatically. Once connected, you can upload your patterns or images. The app also supports self-creation, allowing you to create your own designs.
Next, set the focal length by putting down the L-shaped ruler to touch the surface of engraving area (or just measure the 11cm distance between machine and the surface).
Remember to turn on the Versatile Electric Roller by clicking the button on the up-right corner.
You can preview the engraving area by the motion of the roller after pressing the preview button. You can resize the engraving area by changing the image size inside the app, and the preview area will adjust accordingly. Once you have set up the engraving area, you can begin engraving.
Since we did not have a suitable marker in our office for our test, we will show you a result created by one of our customers. As you can see, her paint was able to fully cover the surface of the cup. Please remember to set a protective shield or wear a safety goggle to protect your eyes.
(Source: @elodiedelassus in INS)
Using a black engraving paper to cover the surface
The most effective way to cover the surface of the cup is to use black engraving marking paper. Its tight surface can completely cover the cup, allowing it to absorb the energy from the laser light.
Firstly, you need to prepare the ceramic cup, engraving paper and a pair of scissors.
Wrap the cup in the engraving paper, measure the approximate length and area, and cut off any excess with scissors.
Wet the engraving paper with water to make it easier to tear off.
Tear off a small part of the engraving paper and paste it onto the surface of the cup. Roll the cup to ensure that it is completely covered by the engraving paper. Squeeze the black engraving paper to ensure a flat surface without any bubbles or folds.
Assemble the LaserPecker LP2 as we mentioned above, and don't forget to measure the 11cm focal length using the L-shaped ruler or your own ruler.
Connect the LP2 to your app via Bluetooth, and turn on the Versatile Electrical Roller. Upload the pattern into the app, making sure that the direction of the pattern is correct. For example, if the cup mouth is on your left, the top of the pattern you want to engrave should be on your right side. You can also choose to invert the color if desired.
You can preview the engraving area and make adjustments to the engraving size by pulling and stretching the pattern on your app.
After previewing, click "send file" with a 2K resolution and set the final engraving parameters. Since the LaserPecker LP2 has a 5-watt power and a range of engraving speeds between 6mm/s-600mm/s, we recommend using 100% power and a depth of 9% with 1 pass.
Now you can start engraving. After you finish engraving, gently tear off the engraving paper with a brush, and your engraving is complete! The pattern is still waterproof and can afford slight scratching.
Another engraved ceramic cup made by our colleague. The parameters are 100% power, 7% depth, with 1 pass.
Ceramic is a versatile, durable, and cost-effective material that can be applied to various areas, including industry and daily items. However, due to its thermal and chemical stability, some procedures may need to be considered to cover the surface of ceramic material for easy engraving of patterns. For hobbyists who cannot afford an expensive CO2 or Fiber laser machine, we recommend using blue light laser and white paint method or a LaserPecker LP2 with a marker or engraving paper for processing ceramic materials.