The photo is a bit blurry to see the bleed but I know what you are talking about. I don't think you will ever get a full seal with shellac in the ply substrate. The cracks from the thick rotary veneer are just too big. I think you could change how you apply the black though. Still apply the shellac sealer but then try to spray a very dry coat of black. It is not easy with cans an air brush would be better. Many dry coats to get full colour.

I came out to the shop the morning and got a better photo.

BH

View higher quality, full size image (4032 X 3024)

My only thought would be to not use the can shellac. Mix your own from de waxed flakes to get a thicker consistency. Might fill the pores/seal faster than flooding with the thin can stuff.

Use a black paint that is comprised more of pigments and not dyes. It's the dyes that are creeping into the grain pores.

Have you tried a black primer, then a black paint?

Do you think the paint might be getting between the prefinished film layer and the plywood? Maybe that finish is brittle or not bonded well?

Good thoughts. I'll see what I can find for a base coat that doesn't affect the Oramask adhesive.

I've completed the current group so this won't happen for several months now. The double coat of rolled on full strength shellac improved the situation dramatically but not 100%.

Thanks for the ideas everyone. This has been a strange problem.

BH Davis

I've been finishing my local brewery's (Caldera Brewery Ashland Or.) wood tap handles for at least the last 10 years. At first we were using Ash cuts from Sawyer's oars until we needed more than they could provide so we started using Maple when the ash ran out.
The process we ran was;
Woodworker makes the handle
I finish with 3 coats of 2k WB poly
Then the engraver takes over; masking, laser engraving, painting black on the engraved surface.
On the first run with the maple the black paint looked to be weeping up under the masking but in reality one of the local wood turners pointed that the paint was being drawn up in tiny voids or straws that are present in maple. So we quit using the maple and went back to ash, problem solved.

Thanks Nick. That is very interesting.
BH Davis

I would try spraying a sanding sealer first. Or mist the black on with a primer first. You would need something that sprays better than a can to mist it. You could also try a water based, clear, grain filler. I also wonder if thinned down hide glue would seal the grain.

Interesting that maple drew in the paint worse than ash. I guess this is the power of capillary action. I presumed the larger the pore the worde the problem but it seems the opposite is true.
The only time I did black engraved graphics in wood was for a dining table. I v carved the female and cut the infill from Colorcore Formica. Then I painstakingly spread pva with a toothpick and pressed each formica letter in place. The outcome was good but I only did it once for a reason.

I doubt the maple is absorbing the color. It is most likely a poplar cross band below the maple that is absorbing it. Not knowing the plywood type, the poplar is a guess at best. With my suggestion on sealing it with hide glue- Id probably do a quick sample of mixing hide glue and then titebond, both thinned, on a flat surface, and see how well the paint sticks to both. I would lean toward using thinned hide over titebond but dont have a solid reason for that. I do think bw the glue, sanding sealer, or a thinned spray coat of primer, you will get it figured out.

I will be the obnoxious voice and say, simply, that wood is exhibiting one of its properties here, and the paint is wicking up the “grain” or vesicles of the Maple. Gee whiz, guys…..
‘Tis its nature, you see. I think any wood is likely to do it, though some more, others less than what you now have. While I support the use of our favorite material, if a change of species and technique does not remedy your dilemma, a different, non wood, material may be called for.
Upon a second cup of coffee, a ply of Wenge, with Maple on top will avoid all this business with shellac and such. While wood is often the problem, it is often the solution as well.

I think you should just go back to drinking your coffee. The sarcasm isnt really needed.

Starbucks -
“Lost in the wash of life” As a friend said this morning about problems we all face from time to time.

“While wood is often the problem, it is often the solution as well.“. Is suitable for framing. No sarcasm, sometimes I surprise myself. I hope you do the same. Two phrases that have bearing on life/work/wood this morning.
I spent my life selling wood as the solution and solved things for thousands of people. I did make mistakes, but the wonderful material wood is, I could overcome any problem. Wood is the solution. Literally and figuratively.

And I will bet lunch that the wenge layer under Maple will work just fine. 1/2” pre finished maple ply it ain’t, but it will not bleed like the various liquids mentioned.

Bernie - My apologies for hijacking your thread with my ramblings.

Maybe you could paint it with the Krylon in a color close to the wood color first. Some sort of tan? Then any wicking would be closer to the wood color. Topcoat with the black last. Just a thought.

Wyatt,

Actually a good thought. That was the idea of trying the Krylon clear first. However not all the Krylon Fusion colors are the same chemical make up. Some, like the clear, react with the Oramask adhesive and make the edges peel. The Ormask adhesive is designed for acrylic based paints. It's rather amazing any of the Fusion paints work with it. But trying a tan is a good thought. Certainly worth a shot.

BH Davis

It sounds like you've tried some solid solutions, but there are a few more things you can try to eliminate the paint bleed. First, consider using a thicker, higher-viscosity paint, which will reduce the tendency to seep into the grain. You might also try using a wood grain filler or sealant in the grooves before applying the paint. This can help to fill the microscopic gaps in the grain and prevent the paint from bleeding through. Additionally, applying a heavier coat of shellac and allowing it to fully cure before painting may help seal the wood more effectively. Another option is to experiment with a light sanding between coats of shellac to smooth the surface before applying the next layer. Lastly, make sure your paint is applied in thin, even layers, as multiple thin coats can help reduce bleeding compared to one thick coat.