I have heard/seen two views on applying a primer before airbrushing with acrylic paints—most suggest using a primer, while a few suggest against, directly applying the paint. What is the best approach?
Second, primers are available in multiple colours: white, black, and grey. When should a particular colour be used?
Thirdly, can the primer be used as a base colour in itself? So a grey primer also reflects a grey paint.
@biswasg
Excellent questions.
Yes, primers are a good practice. They allow the paint to adhere to the primer. Bare plastic is too smooth and has slight imperfections for paint to get good adhesion.
I have done it both ways and get much better results with primer.
You can use any color for primer just as long as it’s a lighter color than your finished paint.
You do not need to buy specific paint that says primer. You can use any MATT finish paint.
Primer also helps you to see and repair defects,and they help cover up small imperfections in your finish
My personal preference is to use a primer before painting. I usually use black and occasionally I will use gray, but that is a personal preference and dependent upon color. When in doubt, you can test on a test model or plastic sheet and see what looks good to you.
Be careful not to apply primer too thickly if your model has really fine detail. It can obscure panel lines, hull plates, etc. I learned when building my USS Missouri. All the hull plate detail vanished under the self-leveling Mr. Surfacer Primer. I know now to be careful.
Great point. I’ve made a mistake too many times with thick primer. Go very very light.
I brush paint, but I also prime my models sometimes, so I think I can help.
When brushing very light colours like yellow, orange, white or red or use Vallejo Model Color paints, I apply a coat of light grey primer to give the top shades something to grip to. For Vallejo, if you don’t prime, paint over the bare surface and then mask, the tape will pull the underlying colour (which has never happened with Revell Aqua paints). For the other shades, the light grey primer is a good way to build opacity while at the same time avoiding to waste paint (for example, painting red over a primer will cover in 5 coats, but unprimed it’ll take 10 coats or more).
I always use primers. With Vallejo its a must. I like to use the primers as a preshade. A single ight coat is all that’s needed as mentioned to many coats and the fine details vanish like magic.
I’ve painted models both with and without primer, results vary depending on paint brand, type, even colour. I tend to prime more regularly when using acrylics, less so when using enamels. I find the enamels bite to bare plastic better and thus don’t always require priming. Acrylics don’t have the same bite.
White as a primer allows colours to be quite vibrant, black primer tends to mute colours a bit. Grey (my go to primer) … well, in between. Priming with a base colour, if possible, removes one step in the painting sequence, which I will take any day.
Priming is a must on most P/E metal pieces as well as most resin I’ve worked with. Aside from biting into the surface better than straight paint, it also gives a uniform colour / texture for the base coat.