Painting wood over laser char?

[Dmitriy Kumets]

Sorry - I tried many searches assuming this had been covered but...

Has anyone tried painting over the char on laser cut BB plywood? I am cutting large letters on a 60watt and the char is all on the edge (no raster).

Has anyone just tried doing an extra coat instead of cleaning first? Are there issues with the paint peeling? Any other tips?

-Dima
PS - I still haven't decided on the paint but am considering an eggshell acrylic base house paint, montana gold spray paint or some sort of gesso coating.

[Mike Chance in Iowa]

I'm not sure what specific plywood I have, but I have at least 3-4 different types of it and I have painted all of them with Krylon, Rustoleum & other generic acrylic spray paints. I've have no problem with peeling and a majority of them all I did was a quick wipe to get any dust off them after they were cut. I have not tested outdoor durability. I typically do 2-3 light coats depending upon the paint.

[Chris DeGerolamo]

brushing may smear the char into the paint. As Mike said, spray paint should do just fine.

[Michael Hunter]

The char (or the resins in it) dissolves in water-based acrylic emulsion paint and comes to the top, spoiling the finish. You need a zillion coats* to cover it up.

Best put a coat of oil based primer or paint (or possibly cellulose lacquer, but haven't tried that) on first, before the finish of your choice.

(* Voice of experience)

[Dmitriy Kumets]

Thank you!
I'll stay away from water based acrylic and try the spray.

[Neil Pabia]

It sounds like you are wanting to put paint on an unstable surface, if you were to use a good primer you would stand a better chance, but I personally would want the char gone and a stable base for the paint. You may want to try Minwax Wood Hardener (or something like that) on the char area just to give it some substance.