Having upgraded to a K40 a few months ago from a few years of using a diode laser, I am well through re-testing all the materials I used before. In the case of engraving tile before, I was able to produce reasonable results using the Norton White Tile method and my starting point was the same, spraying a while tile with white paint (I actually found grey paint gave better results) and using a dither pattern – done using LaserGRBL. So, my starting point was the same, but this was a complete failure in that it was low quality and very light. Having checked on YouTube, I found that it is the Titanium Dioxide in the paint that causes the etch to be black. Most people seem to swear by Rustoleum 2X paint which has a high TiO2 content and indeed my grey paint was but not the white paint I had tried hence it worked better. So, I decided to buy TiO2 powder, suspend it in Isopropanol and spray it onto the tile as directed. This has the advantage that the residue can be washed away with water but the downside is that the alcohol evaporates leaving the powder on the surface of the tile so it can be messy and the machine does need a good clean down afterwards. Although this did lase black, I simply cannot get the same quality as before. I appreciate the resolution of a CO2 laser runs out at about 0.1mm (254dpi) which is a lower resolution than for a diode laser, but the final result is certainly not what I have seen on YouTube so I was wondering if anyone has any suggestions or ideas I can try.
Played this game also… Many of the users doing this at the Lightburn Forum use a variation of this on tile. Mainly using water, TiO2, gum Arabic and maybe white acrylic paint. All of this washes off easily, unlike the alcohol variant that leaves tracks everywhere it touches something.
I did this on the co2 with just water and TiO2, that didn’t come out too bad…
I’ve also done a number using the forum formula… both fiber and co2.
Don’t know about this… Many of the lasers that have concentrated beams or just 0.08x0.10mm spots…
My Chinese laser out to the box would do 0.10mm dot.
With a compound lens, down to 0.05mm, for 508 dpi… Haven’t seen a dpssl laser on a hobby laser there yet … at visible light frequencies.
On the fiber a 0.254mm interval for a 1000dpi is possible with a short lens.
If you haven’t watched the Laser Everything video on photo engraving you should check it out… it shows how to find the interval (dpi/lpi) for any laser with any material… Some insight into how to use the dot adjust in Lightburn from one of the developers…
You have a nice machine, don’t underestimate it’s abilities…
Good luck
Yes that is an excellent image and is what I am looking for. I have looked at the Laser Everything video series and understand the principles of carrying out the checks to maximise the resolution and achieve an ideal contrast. When you say water how do you apply that and you say white acrylic paint which might be worth a try. There is only so much I can do using K40 Whisperer and Inkscape and I have tried using ImagR so I clearly need to persevere and get the best set of variables so perhaps it is time I changed my controller and moved to Lightburn which is where I do intend to get to.
Yes a controller upgrade is something to look at…
I know a dsp type of out of range, money wise, for a k40, but it’s a much better controller… Actually has the proper control lines for a laser…
Good luck