yeah, youll need to put a layer of primer down first, then once thats fully dry, your main coat, then the varnish after that. Make sure you let it all fully dry, otherwise itl start to flake after a little while
All Wrong! (ish)
To paint a hopper properly it needs to be done from the inside in which case you need to spray the final coat first and then work backwards to the undercoat and then seal it off with lacquer. This is the only way that it's guaranteed to last. This only works tho if your using clear shells, if you have coloured shells then spray from the outside but ignore the primer coat and just go straight on with the main coat. That may sound weird but to do it right you need to use the correct paint, car paint will look great for 2 minutes and then flake off and you've just wrecked your hopper.
The paint that you need is
Polycarbonate Paint for lexan remote control car bodies. It's available at any good remote control model shop and available in spray or brush format.
This paint literally eats itself into the surface of your hopper and will flex as you bash your hopper about so it will stay on the surface as you intended it to. Car paint will just flake off and look rubbish.
Simple metalflake clear coat backed over with a candy blue but done from the inside.
done 2 years ago but still looks the same today despite being bashed around in my kitbag