I tried the water/PVA/TiO2 mixture with a Universal Laser Systems(ULS) 60W machine by setting up a narrow tile-wide grayscale pattern set to lowest power it seemed to remove the coating instead of blacken it.
Because it was the lowest possible power setting I tried the fastest speed and still it looked like it removed the coating instead of blackening.
To verify the coating had TiO2 was OK I used my small Ortur 4W(actual) diode laser on the same tile. I made a 4x4 grid of squares in LightBurn setting to different speeds across the 4 rows and increasing power across the columns.
I was able to get blackening in the 4x4 grid using the diode laser.
Anyone have any thoughts on if it’s possible to do the Norton White Tile method with a ULS 60W laser? I’m hoping to expose some middle school kids to creating a solution( water and PVA and food coloring ) and suspending the TiO2 for an even application. So a bit of chemistry with some artistic flare. But I’d like to use the school equipment(ULS 60W laser) vs bringing in my optical diode laser.
Thanks.
Hoping @jkwilborn has some insights since IIRC he’s used a CO2 laser to do NWT.
The software doesn’t provide speed numbers, just percentages just as it does power but it does have a DPI setting which was first tested on the default of 500 but for the 2nd pass which was at min power(10%) and 100% speed I tried 300 DPI but I should have tried a minimum like 100 or 150 for the 2nd test. I’ve seen posts that CO2 lasers can do this but the sweet spots are tricky to find and the ULS software(not LightBurn) isn’t as easy to work with as LightBurn.
Takes very little power. My 40W is set to about the lowest it will lase, around 10%.
Interval is also an effective adjustment. The laser everything video on photo engraving is good for determining a proper interval. You’ve probably seen it, but other may not have.
A good thing to have is either a microscope or image magnifier. I have one of these from Amazon that works better than the microscope. A good thing to have is either a microscope or image magnifier.
It has a tendency to just blast everything away with any higher power. So I’m running in the dpssl range of < 4W.
I run the LBT100 stuff at low power also, the process is similar with all these coatings.
LBT100 recommends a thin coat and low power, as do the other manufacturers such as Cermark.
A thicker coating lowers the available interval, hence resolution.
I’ve started to do more of these with my fiber than my co2…
I tried again with just the one coat, 10% power, 50% speed and 100dpi on a black to white gray scale and it still obliterated the coating and no color change in the transition to the white end.
And I agree with you that the ULS cartridge is not your typical water cooled DC excited CO2 laser. I still see their spec saying it’s CO2 so must be RF excited CO2 and some special cooling configuration.
I would look around for some power grid templates. That way you can get an idea where you are at. Unfortunately it only works for a particular batch if you’re using the DIY method.
There is an amazing amount of information about white tile method over on the lightburn forum. There’s a lot of opinions!
I’m tempted to give the white primer a try just to see how it does but what a PIA the UCP software is. It does not work with LightBurn so I can’t use the Laser Tools- Material Test grid generator.
UCP only has a few colors to pick to make settings changes to so I thought my best bet was a gray scale generated in Adobe Illustrator going from black to white was my best shot and then I could set the max power in a repeating steps by moving the grayscale image strip, adjust the speed and running again. But, the lowest possible power, 10% just cleaned the tile of coating so it seems the lowest setting is too high power.
I was hoping to give the kids some chemistry hands-on by having them mix the water, PVA, food coloring and TiO2.
I was thinking the same thing about grayscale so I painstakingly tested more than a dozen settings by creating one square, burning it, changing settings, burning it, etc etc. Still did not get/find a setting of power/speed which could get me anything close to even a light gray color.
And it has to be an RF excited CO2 instead of DC excitation and thought I mentioned that along the journey. The tube is too short to be a DC excited CO2 laser.
Unfortunately I had to give up on the idea of presenting the NWT project to the class. It was planned in hopes of them being able to make a gift for a family member for the holiday break. And ULS has not returned my support request regarding using their laser for NWT making.
Sorry to hear this… I’m sure your students would have found it valuable…
Maybe getting a machine like this for students isn’t really a good idea as there doesn’t seem to be much information available and proprietary software is usually sucks.
It’s bad when you don’t know how fast 100% relates too…
Tell me about it but it seems to be a very common machine for K-12, colleges and universities. Money to burn I guess and it’s got to have a service contract.
I hate to say it but nobody could even fix some simple Simplex synchronized clocks at my daughters elementary school a few years back. Teachers were covering up the clocks so kids didn’t see the wrong time. I took one home, figured it out and fixed it and started going through all the classrooms when I was told to stop because it was the job of a school district employee even though they couldn’t fix them and had been called out many times. A week later I was told all the clocks would be replaced with battery powered clocks. ugh.
I am coming in late on this one, but I am having the same problem in etching white tile with my K40. I had achieved very good results image engraving on white tile using my previous diode laser and using a grey primer coating worked best for me (better than white primer). In the meantime, @jkwilborn directed me to Russ Sadler’s videos and I learnt that it is the TiO2 in the paint that produces the darkness of the engraving which answered the question of why some paints work better than others. So, using a high-definition test image I use which works well on my K40 on borax coated acrylic pad and grey painted tile, I wanted to try a TiO2 powder solution to further darken the image. The preparation prescribed is to produce a solution of TiO2 and isopropal alcohol and spray it on the tile. After trying several images and a power/speed matrix, I simply could not get anything that compared to grey paint and it made a mess inside the machine, so I gave up on this method. I then spotted an alternative method that @dougl describes to produce a solution of 1-part TiO2, I part PVA glue and 3 parts water and paint it on the tile with a foam brush. Although this was cleaner inside the cabinet, it also did not produce good results either yet the results I have seen do seem to be excellent although these were all done using diode lasers. I then saw a further post to simply apply masking tape to the tile and again, I would say this is no better than the TiO2 results, and I still need brush thinner to properly clean off the residue burnt masking tape so I’ll be sticking to grey primer unless anyone has any other ideas.
