Finish spraying with Enamel

Over time I have heard folks mention they sprayed on a tack coat, then later layed down the finish wet coats. The dry "tack coat" they sprayed on was done from quite a distance, and it left a spotty dotted look, with bare surface still showing between the paint dots. They felt that gave the final finish coats some "teeth" or "bite" for adhesion.

Those paint dots from the first coat makes for a rough surface, such as you described orange peel. If your first coats are being applied with that dotted appearance, that might well be the cause of the rough finish.

One or two light coats at the start is good, but they must be smooth and give full coverage. And the term tack coat, does not mean to spray on a dry dotted layer. I think it just means light and smooth finishes, wet enough for good surfaces that accept further applications, to arrive at the desired smooth surface for final finish.

Your thinning ratio sounds about right, but depending on the project I might thin anywhere from 1 part thinner to 2 parts paint, (1:2) or even as much as 1:1, when using enamels. Good luck getting it sorted.

Patrick

Thanks for the reply Patrick. 

I tried painting again earlier today, laid a few light tack quotes and then I covered it in a very wet coat. 

The gloss finish is perfect on it, however it seems to have attracted so much dust and bits so I’m not very pleased. We don’t have an extractor unit so its susceptible to the environment. I think I may have to build a small unit, would certainly take all the pain out of it. 

I find I must have proper lighting to get a good gloss coat.  I follow all the steps you do, but when I put on that last, wet coat,  I have the light positioned so I can see the direct reflection of the light on the model surface I am painting.  That way I can see the wetness build up by judging how shiny the wet layer is.  If I cannot see that direct, specular reflection I do not get good consistant gloss finish.

I call getting a good gloss coat an exercise in brinkmanship.  You must keep applying the paint until just before it runs.  How do you know when it is about to run before it actually does?  Experience, that is the only way.

Also, I often thin that last coat a bit thinner than I do the earlier coats.  I find it is hard to spray a very thin coat over bare plastic or even primer, but hard to get a good gloss unless the paint is thinner.