I’ve been trying to make laser cut jewelry with different woods. I practiced with draftboard, then tried birch plywood and walnut.
Whenever I paint the pieces, I give them a ton of drying time, and coat them with polyurethane spray. Still, days later the paint can be easily peeled off and the wood looks normal again. (I also sand before I paint anything). It’s like the paint just sits on top of the wood but is never really sealed off no matter what I try.