Laser Engraving, Masking and Painting Help

[David Fierstien]

Hi everyone, I'm new to this site, but my google searches keep sending me here, so here's my question for you experience laser engravers/woodworkers.

I've been laser engraving for many years, love it, keep super busy with it. Recently, I've started engraving and painting. Currently, I'm using 1/2" birch plywood.

My process is, I sand the plywood nice and smooth using 220, then I paint it. I'm using a paint and primer combination paint from Home Depot and paints the wood red or blue or whatever other color I paint it. And then apply paper application tape over the top of the wood. I then engrave the design on my universal laser engraver which has air assist and outside ventilation. During the process a lot of times the tape comes up off of the wood, which i'm trying to figure out how to prevent. Generally once I am done engraving I use a sprayer and spray a layer of polyurethane over the top of it, let it dry for two hours and then throw another coat of polyurethane over the top of it and let it dry for another two hours. Then I can paing the project, let it dry and remove the paper application tape. Many times there's a little bit of bleeding, I personally think that's coming from the paper application tape coming off during the engraving process.

My question for you experienced woodworkers is what am I doing wrong? Is there a better way to keep the paper application tape applied to the wood during the engraving process, should I be putting a layer of polyurethane over the wood before I paint the wood? I'm just trying to refine my process so it looks beautiful when I am done and i've run into a stop where I don't want to keep going until I figure out what I need to change. Should I be using a different type of wood, different process, etc. My templates are 32x18 and 24x12 on my laser.

Any help or suggestions would be great. Thanks so much for any suggestions.

David