Having talked with @RoughDraft40 about the Nicky Norton Method of laser engraving a ceramic tile permanently, I started using the method today. Apart from lots of tiles and a laser, I needed to obtain some white spray paint and some acetone.
Step one - Method: The four tiles which I prepared were wiped over with acetone. I understand that ceramic tiles may have a coating that is resistant to paint. Cleaning the glazed surfaces of the tiles with acetone was very quick and it dried rapidly. I then sprayed the tiles with a coat of Rust-Oleum all surface, matt paint which was described as Flat White in colour.
The tiles were touch dry in 30 minutes and the paint can be re-coated after one hour. Re-coating was not necessary and I left the tiles to dry completely for 24 hours. The image was grabbed from Google as a screen grab and left as a PNG file for Lightburn.
My settings follow: Feed rate 250mm at 100% power. The image was a line drawing so I did not need much resolution and I set the interval to 0.180 which equates to 141 dpi. The image mode was set to Stucki for high quality dither and more speed than Jarvis. Cells per inch numbered 50 and the halftone screen angle was 22.5° Total burn time was a shade over 3 hours.
The tiles were painted with a light coat of paint until they looked to be matt finished.
The laser engraving apart from the paint is as one would normally undertake. There is a faint clouding of the image because the white paint is still in situ.
The completed image looks slightly veiled because of the white paint which still required removal.
Tah Dah! The image was wiped with acetone and the white paint came off very easily. The permanently engraved ceramic surface is still shiny, having been protected by the paint. This method produces a very high quality finish and it is very easy to achieve. I can recommend it as another process to increase the versatility of the Shapeoko CNC machines. I have seen other people suggesting the use of black paint on a white tile. I see no need for it if you want the engraving to reflect the image exactly as it was produced.
Next on my list will be engraving photographic images. I use Affinity Photo and if anyone here does use that and wants to try laser engraving of photographs on tiles, I use a method of creating pencil sketches that may prove useful. I reproduce it below:
- Import image [⌘+O] for open or (place) image
- Duplicate background image - [⌘+J]
- Add B+W adjustment layer (then add that to the newly duplicated layer)
- Menu Bar - Layers - Merge visible (or right click for context sensitive menu)
- On the merged pixel layer - [⌘+I] to invert the layer
- Change the blend mode to colour dodge
- Add live filter to newly inverted layer - gaussian blur
- Move radius slider to the Right to see and adjust the pencil sketch effect
Mac users will know the [⌘] key.
Windows or Linux users will need to substitute it with the [Ctrl] key.
A brief clip of the laser in action will give some idea of the speed with which the job was engraved.