I finally had a chance to play with something I’ve been meaning to for some time: trying to laser scratchboard!
Scratchboard is a wood board – much like draftboard – with two layers of paint on top, a white under-layer, and a black top layer. You’re meant to scratch off the black layer to reveal the white. I figured I could use my to scratch with
I chose to score one piece from a series of algorithmically-generated human-like figures that I wrote in Processing.
Settings
Manual Score
Speed: 500
Power: 8 (though anywhere from 3-10 works fine)
These boards were 5" x 7", and 1/8" thick, from Ampersand.
I also tried engraving, but the effect is pretty binary – it’s either white or black. Dithering worked “okay”, and you have to reverse the image since you’re removing black.
Really, I think it looks great for very graphic, thin-line vector art, or engraving bold, graphic images. There’s a slight discoloration to the white under-layer, making it yellow-ish and not as white as when I use a X-Acto blade to scratch with. I’m guessing it’s burning the white layer just a touch. Also the start and end of each line has a slightly wider round point to it (you can see in the detail pic above).
I would think it’s possible given people use acrylic paint as pre-laser masking already; you might just have to start at 1 pew and work your way up until you get through the top layer.
I also wondered if I could get through the white layer on these, creating three color images (black, white, brown wood underneath) but I didn’t try that; DIY boards might be able to more layers with specific colors…
Now, I figure if it’s meant to be used by scratching off the surface, creating dust of materials that can be “irritants” if you breath in while hovered closely over it and these, zapping it with a few pews with a suction fan going might not be terrible. And yes, I know there’s a different when things are burnt versus disrupted via mechanical means, but these MSDSs don’t show any chemical or burning details.
Indeed - I had tested that but it was rubbing off the black more than brightening the white. I might have been using a too-rough cloth, or any of the bunch of things , so I figured I’d just leave it as “good enough”.
to scratch with 
