@jkwilborn TiO2 Method
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Thanks for the link.
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Denatured alcohol is ethanol plus methanal (to make unfit to drink). Is this what folks are using?
I use Everclear.
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They don’t use methanal (formaldehyde) for denaturing but they do use methanol (methyl alcohol).
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Silly little a
The brand I have on hand is KleenStrip. Everclear isn’t available by me. But as long as methanol isn’t a problem I’m good to go.
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Everclear is booze for drinking.
Keep in mind you breath this stuff, so methanol might not be the best choice.
Have fun.
The small amount of methanol that’s in methylated spirits isn’t usually considered an issue in normal use. It’s just there to stop people drinking it!
Ah! What we call White Lighting !90 Proof
I’ve been using denatured (DNA) wen I mix up dewaxed shellac for decades. I’m still around but I’ve noticed that I’m a little shorter than I was.
That is called getting old. 
I’ve got a 4W diode( Orture LM1 15W ) and getting back to NWT to try and get some of the artists in my Middle School classes interested and wondering if everyone is still doing Dithering or has grayscale been the norm now? I say now because 3-4 years ago when I was doing this I couldn’t get grayscale working and found Jarvis dithering gave the best results.
I’m starting off with white paint as I’d done before and validating the requirements before I switch to elmers glue and TiO powder which have both been acquired in classroom quantities.
The material pattern feature of LightBurn was used for this but the text didn’t burn.
That actually looks like a pretty good material test. Text needed more power or less speed.
It’s quite amazing a little 4-5W laser can do NWT projects, hence the interest in teaching middle school kids about it since the equipment is not out of their family budgets in many cases. Not speedy but pretty good.
I expect to use 23mm/s and 90% max power for my layer settings. But I’m wondering if everyone is using dithering or grayscale for designs with different levels of gray.
Dithering is best for images.
Greyscale is unpredictable because the relationship between tones is non-linear and varies wildly depending on the material.
Greyscale is better for 3D texture engraves.
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I has my best luck with Greyscale, but most do best with a dithering mode.
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Is that on a diode or a tube(CO2) machine?
I know diodes often have a beam which is rectangular instead of circular and you can get odd effects in different axis of motion because there’s more power along the axis parallel to the beam shape and then overlapping power when the beam shape is perpendicular to the motion.
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Do you mean the vertical banding? That watery sort of vibe?
If so that’s mechanical, its from the sudden change of direction wobbling the toolhead ever so slightly.
Fixing any mechanical slop in your machine, increasing Overscan (so that it has more of a chance to smooth out), or lowering acceleration in your firmware (so it jerks around less) should help.
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Yes that curtain effect. It seemed to correspond to the teeth on the belt. But maybe it’s like you say a resonance from changing direction. Next time I will play with accel. and overscan to see if that helps.
I upped the DPI from 72 to 256 in GIMP and tweaked the edges and contrast then decided to try one grayscale at 23mm/s 10%-90% power and it’s looking pretty good with white paint.
I did goof and forgot to blacken the outlines and letters so while they are darker, they are not black.
I’ve fixed that in the png file so next ones can/will have darker outlines and lettering.
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