Interresting

Hi ZASto,

I appreciate you are not running your laser with Mach3 but give the Norton method a try and perhaps report back with your findings.

Tweakie.

Will test one of these days with 2.5W blue laser (controlled with GRBL), and report back.

Interesting, hadnt heard of that technique. I like it.
I also find that black marble tiles do an excellent white image
 on the black tile as it cracks it slightly and the cracks are white.
Good contrast.

Art

Hi Art,

I have never tried a black marble tile, something to add to my list. 

With white ceramic tiles, the laser process I have used in the past creates small fissures in the glaze which are then filled with Rub’n’Buff (or similar) to create the image. Although long-lasting those images are not permanent (at least when subjected to paint stripper) so it is good to try another process.

I have now given up with the Mach4 laser raster process, too many problems. Perhaps, one day, it will all be resolved but sadly I have tired of waiting. 

The following pic shows the fissures produced in the glaze from my conventional laser engraving.

Tweakie.

Tweaky:


  Great thing about the black marble is the scattering of the light makes it turn very white at the cracks, so no rubbing needed. Pretty brilliant image. (Hmm, it may have been polished black granite tile..,Ill have to see if I can find the same I did..)

  Sry to hear the M4 laser isnt quite there. Im sure they'll get there eventually.

Art

Hi Art,

A few weeks back I laser rastered a couple of dozen small pieces of slate with different vehicle logo’s and other designs as part of a young children’s discovery game. The engraving turned out to be a light grey and reasonable contrast to the base material without any filling being necessary. Still looking for some black marble. 

Tweakie.

Way back in Post#1027;  https://www.machsupport.com/forum/index.php?topic=12444.msg250840#msg250840
I showed a picture of how I modified a ribbon cable to invert and change the pin allocation of an Active High, 57CNC generated PWM signal for connection to the Active Low input of my laser PSU. At the time no interest was shown but as coincidences go I have just had two requests (from different sources) to explain how the transistor is connected and how it works. On the off chance that others may also be curious, the following diagram shows the connections and explains the mystery of how the transistor gets it’s Vcc. 

Tweakie.

Hi ZASto,

I appreciate you are not running your laser with Mach3 but give the Norton method a try and perhaps report back with your findings.

Tweakie.

Well, you know that it's not Mach that I use for laser control, here are some samples, "fresh under laser"

Chinese blue 2.5W

2 different tiles, one with shiny glaze, other with mat surface.
Coated with white acrylic paint (from rattle can).
Controlling software was LaserGRBL, speed 700mm/min, power 245 (255 = max)

Enjoy pictures.

https://youtu.be/J_xjTOJJHs0

Excellent test results ZASto.

Because different laser wavelengths have differing effects on many materials it is most interesting to see others results on ceramic tiles.
Did your lasered paint infuse into the glaze so that the image cannot be removed with scraping or with thinners ?

Tweakie.