Tools Required: Respirator, Spray Booth, Spray Can Primer, Aerosol Spray Paint Applicator, Alligator Clips, Wooden Skewers, Styrofoam Boards.
Now that you have finished building and modifying your kits you may want to paint it because you are not satisfied with the colors of the plastic, you may want to create a custom color scheme or simply because you just enjoy it.
This is where priming comes into play. Applying 1 or 2 layers of primer is, in my opinion very important in order to achieve a higher quality paint job. Basically, you should think of primer as the “paint” you apply before the actual paint.
It serves 3 main purposes:
It gives you a neutral canvas to work on. Recoloring a black piece with red for example, will require several layers and the base color might have an adverse finish on the final paint job.
It reveals the scratch marks and imperfections in the plastic left behind by the earlier sanding and modifying processes. If a layer of primer can’t hide it, it is very unlikely that the final layers of paint will be able to do so.
It provides a surface for the paint to stick on. This is very important as some types of paints such as acrylics are easy to scratch off.
Some primers act as micro gap fillers and thus mitigate the side effects of your sanding job.
Once your kit is ready to be primed, separate the pieces in batches that are to be painted in the same color. I put them on skewers with alligator clips attached. I usually sort the colors on styrofoam boards, this makes the painting process much more manageable and less time-consuming. Some modelers assemble their kits entirely and then apply the primer. I have tried that method several times in the past and I found that I often forget spots that should be primed for paint, under the skirt armor and shoulders are perfect examples.
During the judging process at competitions, if a judge notices that there is no paint under the armor of your kit, it is more likely that you will lose a point. But at the end of the day, you should adopt the method that suits you best.
Once your pieces are ready, you can start priming, it is very important to use a respirator, primers smell very strong and have chemicals that can harm your lungs, I have built a spray booth in order to do it inside my apartment and even then, I have to go at in small batches, otherwise, the entire apartment smells awful.
The respirator that you will want to use must be using organic vapor filters. If you do not have the space for a spray booth, you can do it outside. Just make sure you do not do it when the wind is blowing in your direction, you will not enjoy what happens next.
IMPORTANT DISCLAIMER: A spray booth does not replace a respirator. Both items should be used together.
I started the hobby with Tamiya primer, it comes in white, light gray and dark gray. I often use white but if my final paint color will be white, then I go for the dark gray primer.
Nowadays, I tend to use Mr. Surfacer for my more serious builds, I find Mr. Surfacer to have a smoother surface when it dries, the drying time is much shorter (around 20 minutes) and it comes in various types. They have 500, 1000, 1200 and 1500. The higher the number, the finer the compound is. The 500 and 1000 types are ideal to fill those grooves in the plastic left from your sanding job. 1200 and 1500 act more as primers. Usually, the way I go about it is I will first spray my pieces, inspect them after the primer has fully cured, sand them down again if imperfections were found and apply another layer of primer again.
Wipe the pieces with a soft brush or cloth to wipe off dust and hairs. The primer can seal them under the layer and paint jobs won’t be able to cover them. You will have to sand the surface down, clean it and prime again.
I use an aerosol spray paint applicator to have greater control on my spraying but that is purely optional. Keep the can at about 10-15 cm away from the piece and with short bursts, go from left to right, stop and again from left to right. You can go from right to left, the starting point is not important. What is very important to remember is to never stop midway on the piece that you are priming. If you extend the duration of your burst, you might apply too much primer, which will give a very thick look to your paint afterward. I usually wait 24 hours minimum to give the primer enough time to cure before I start working on the pieces again.
In the event that you find an imperfection or you touched the wet surface, it is very important that you do not panic. Let it dry. Once the part has fully dried, you can sand it down and reapply primer again. Make sure to wipe it off with a cloth to remove excess dust before priming a second time.
I have seen modelers completely cover their kits with primer, to the point you do not see the color of the plastic underneath. Sometimes after I spray two thin layers, as you can see on the SD Freedom above, the base color of the plastic is still visible underneath the primer. I have not seen any difference in results in having a piece completely covered with primer compared to one where the base color is still visible. Primer is not cheap so might as well make it last. Once the pieces are dry and to your liking, you can start painting.
Once again, it is very important that this process is done in a well-ventilated area, outside if possible and that you take breaks in order to get some fresh air (no pun intended).
Look forward to my painting article.