I am applying Model Masters acrylic paint over plastic. The paint does not seem to stick to the plastic. If I mask a portion of a painted area to paint the adjacent area and then remove the masking tape, a good portion of the paint will remain with the masking tape leaving a very big blotch of unpainted plastic.
Should I apply a primer first? Is so, what primer? Should I rough up the surrface with sand paper before I paint? If so, what grit should I use? Should I do both? Or something else?
I was prety good at painting when I was a kid. What happened? Did they change paints?
Acrylics pretty much demand an absolutely spotless base to be painted on. Mould release oils, left-over sanding dust and even oil from your skin will prevent acrylics gettting a grip on the surface.
Before you begin to paint, wash your model with warm soapy water. Some people wipe down the surface with alcohol before painting. Handle the bare surfaces to be painted as little as possible Using a primer and/or lightly sanding the surface will help give your top coat a bit of bite.
Use a low-tack masking tape whenever possible. Tamiya’s masking tapes are great - low-tack and they trim very easily with a sharp knife.
I’d primer plastic, so you have a surface that can provide a little ‘tooth’ to the acrylics. I use an AB to prime most of the time, but can also use sprays. Krylon’s are good, as are some of the autoprimers. There is a krylon plastic spray now. Key with using a spray can is the same that applies with airbrushing: multiple light coats, which often will dry while you are spraying another part of the model. Key thing is to give yourself something besides bare metal/plastic/resin for the paint to stick to.
Krylon is an oil based primer. Can you apply acrylic paint over an oil base paint? Are there any special considerations that should be taken in account?
Ross…the maker’s of Simple Green should give you a royalty for all the advice. But, no doubt…I picked some up on your recommendation…spritz, wipe, rinse and dry. Done!
Yes, though…have to get release agents et al off that plastic!
I simply wash my model with liquid soap and allow it to dry. I then prime with a lacquer based primer like Tamiya’s. The primer helps to “lock-in” any oils, dust or contaminates that the washing might have missed. This gives the acrylic paint I use a “clean” surface to adher to. I’ve never had problems with this process.
Don’t I wish! I absolutely fell in love with the stuff. Best thing since sliced polymers… We buy it by the gallon and use it to clean almost everything. The only thing I never use it on is cranberry juice. The combination turns black and permanent! [:O] Must be some very interesting chemistry, there!