Enamel over Acrylic

Ross & Mike,

Thanks very much for the replies.  I'll sure place your responses in my AB notebook.

After considering the color in Floquil I was going to use over the Polly Scale I found that I can replace the Floquil color with a Polly Scale color that will work.

Ross, interesting that your thinking of trying Polly Scale as a primer. I was considering using a lacquer-based automotive primer-surfacer in a rattle can as the undercoat but taking note of your comment about the possibility of Polly Scale doing a good job as a subbase my try it myself.

The subject in question has a laminated basswood hull that has a base finish color of light gray (5-L) with some black patterns on the hull above the water line and Oxide Red below the water line.

Thanks again for the input gents. I think you have my gray (is that 5-L) matter started in the right direction.

Patrick

PS Mike, thanks to your thread on the Badger Spray Booth I have one on the way and it should be here any day. So, I'm almost ready to actually getting started on the project.

Well, that was pretty silly! (My original answer, that is. Dyslexia, you know. My name is Liz Dexia. Youse can call me Dizzy…)

Sorry 'bout dat!

To answer the question you really asked:

If the acrylic was applied over a clean substrate and is fully cured. Polly Scale has tremendous adhesion when properly applied and cured—I may even start using it as my primer of choice.

There are some things to watch out for, though: Some enamels contain solvents that will attack acrylics. As I don't use Floquil, I'm not familiar with their formulation. Spray a test panel with Polly Scale, allow to cure for at least 24 full hours. Spray the Floquil just as you plan to over the model and then wait another 24 hours. Carefully inspect the finish for problems. Burnish some masking tape over the panel and pull up. Properly applied and cured Polly Scale, provided it has not been affected by the Floquil, will not pull up with the tape.

The other thing to watch for is crawling, commonly called alligatoring, which produces map cracking in the finish. Enamels shrink more than acrylics, and it is possible that this will occur.

This is not to say that any of this will occur—many people use enamel clear coats over acylics with no problems. These are just the things that may occur.