Mrchntmarine
So now i have a question -
have been using plastikote and worked good, but... The last model i used the white plasticote primer and noticed while brusing with tamiya acrylic, it didnt seem to stick well and I had to paint multiple coats...
That you were using Tamiya acrylics makes it necessary to ask you for some additional info.
First, did you apply the Tamiya paint by hand or with an airbrush? And second, did you thin it with Tamiya's proprietary acrylic thinner, with some other thinner, or did you apply it without thinning?
I use Tamiya acrylics today with no issues, but I had to learn some things along the way. I applied them by hand long before I started using an airbrush, and I did not thin them.
I noticed similar problems to what you describe. I would lay down a color, let it dry, then try to lay down a second coat of the color. The fresh paint would lift off the dried paint, and it would clump on the brush. Eventually I read a post somewhere that Tamiya paints are formulated for airbrushing, and are meant to be thinned for use. I started thinning the paints when hand-brushing, but I tried water, and isopropyl. Neither worked. I still got paint lifting, and clumping. Then I started using an airbrush, and I bought a bottle of Tamiya's thinner, to thin the paint for airbrushing. That worked best for me, and I also tried it for hand-brushing. That worked best, too. I can apply the color by hand and get a coat as thin and fine as if I had airbrushed it.
The only exception to using Tamiya's proprietary thinner, in my experience, is that I can use lacquer thinner, too. When airbrushing, lacquer thinner gives me an absolutely dead-flat matte finish. It's no good when applying paint by hand, though, because the thinner is too hot and it ruins the paint already on the piece.
If you're already thinning your Tamiya acrylics with Tamiya's acrylic thinner, then I can't explain why the paint didn't work for you over Plasticote primer.
Best regards,
Brad