Airbrushing 203: Freehanding Multi-Color Camouflages
Up to this point, one could achieve good results with any airbrush, from the most expensive precision type to the cheapest spray gun. All that mattered was that the airbrush put out a consistent spray and the paint was properly atomized. With this article, though, we move into the real strength of an airbrush: that of becoming a scaled down spray gun. Here your choice of airbrush plays a very important role.
Materials & Equipment
Airbrush: Harder & Steenbeck Infinity double-action gravity feed
Compressor: Harder & Steenbeck Euro-Tec 10A with pressure regulator
Spray Booth: Model Expo Compact Spray Booth
Paint: Testors Model Master Enamels
Subject: Hasegawa 1/72 F-4EJ Phantom II
For painting a freehand camouflage, the airbrush needs to be able to hold a fine line. This is determined by the diameter of the needle and nozzle. A smaller opening in the nozzle, with a corresponding smaller needle, will result in a much finer line. Your choice of airbrush will be controlled by how fine a line you need. If all you build is 1/32 and larger aircraft, you can get by with a larger nozzle. If you want to freehand camouflages in 1/72 or 1/144, you will need a very fine nozzle.
Preparing to Paint
With the proper airbrush selection out of the way, the next step is to set things up for painting fine lines. Before, with single colors and masked camouflages, the primary concern was putting down a smooth coat of paint. This was done with a relatively high pressure and moderately thinned paint. To get a fine line with minimal overspray, we will need to modify things a bit by dropping the pressure down. A lower pressure will reduce the overspray potential, allowing the modeler to paint finer lines. In this case, I dropped the pressure down from 30psi to 20psi.
With a lower pressure, the rest of the painting equation changes, and to achieve a proper balance we need to change the paint as well. In general, the lower the pressure, the more thin the paint needs to be. Also, the closer you get to the subject, the thinner the paint needs to be. This is going to require a lot of experimentation, even if you have done this a hundred times, as environmental variables will introduce subtle changes as well. The best thing to do is to have a clipboard with bright white paper sitting next to your spraybooth. Use that as a palette and start spraying your paint. If you are seeing splatters, the paint isn't thin enough. If it is translucent and creating runs, the paint is too thin. In both cases you can adjust the air pressure a bit to even it out, or you can add more paint or more thinner. It will always be a balancing act, so be ready for some fiddling around to get everything dialed in right. Remember, even if you are using the same brand of paint, switching to a new color can result in a different thinning formula as well, depending on the various additives and fillers in the paint.
Preparing the Model
Since you will be freehanding the camouflage on the model, several things need to be in place before painting. The first one is that you will need a very sturdy and comfortable handle to hold the model with. If you are using a fast-drying paint like lacquers, you could hold the model itself, as long as you wear a protective glove. With curative paints like enamels, though, any handling during the painting process can result in fingerprints showing up. Propeller aircraft are easy, as one can simply insert a rod into the propeller shaft. Jet aircraft can be more problematic, but a rod inserted into the exhaust generally works.
Like with the masked camouflage subject, it is generally best to work from lightest to darkest in colors, but there are some situations where that is not necessarily the best choice. The camouflage on this Phantom is such a situation. Logically, working from lightest to darkest would mean starting with the underside light gray, then moving on to the upper surface colors. However, as several of the camouflage colors work over the edges of the wings and fuselage, this would be very difficult to maintain a consistent line between the upper surface and lower surface colors. So we will start with the upper surface camouflage and finish with the light gray undersurface color.
Painting the Model
With all the preparation out of the way, the next step is to start painting the camouflage. One of the reasons I wanted to do a Vietnam-era Phantom was to fade the camouflage. While I could work with adding various tints of black and white, I chose the simple route and used the underside camouflage gray as my tinting color. The key to mixing paints for airbrushing is to use the same brand of paint for your mixing. While it is possible to mix similar types of paint (for instance, Brand A enamel and Brand B enamel), potential formula differences can cause problems that are difficult to diagnose. In this case, I started with the tan and added a few drops of the camouflage gray. To ensure thorough mixing, I used a mixing cup. This also has the added benefit of being a larger container than the paint cut, which is very important when mixing custom colors. You will always want to have more paint than needed, just to make sure you end up with thorough coverage.
For the base tan color, once I mixed the paint up and thinned it properly, I painted the entire upper surface of the model with the color. I could have painted just the areas that will be tan on the finished camouflage, but by painting the entire upper surface tan I gave the model a good surface for the penciling project coming up. It also provides a uniform base for the subsequent colors, which is more important when dealing with spraying demarcation lines.
Once the tan was on and had dried for a couple of days (enamels require a longer drying time than lacquers, due to the curing process), I drew out the camouflage pattern in pencil. I drew on both the medium green and the dark green sections, clearly marking each with a G and a DG inside the lines. It is best to use a soft pencil, so you don't press a line into the paint. You also do not want too dark a pencil, as that will require more paint to cover up.
Spraying the Demarcations
With the base color down and the pattern marked up, the next step is to get that camouflage together. The next color is the medium green, and like the tan, I added a bit of camouflage gray to lighten it up. With extra mixed up, I put a little bit into the airbrush paint cup. It's better to have too little here than too much, as with the various twisting and turning you'll be doing, it is too easy to spill a cup that's too full. Few things ruin your day as much as dumping a cup of paint on your carefully painted model.
Even with this method, you will still very likely end up with hot spots. These show up as shiny spots at the beginning and end of your brush stroke, and it marks where more paint went onto the surface of the model. Given the small area we are working with, these are not going to be much of an issue, and once the paint fully cures they will disappear for the most part. That which does not disappear at that point will do so once a clear coat is applied.
Once the initial demarcation line is drawn, the next step is to fill in the color. To protect the fine fade line that you've just drawn, keep the airbrush set for the fine line and fill in the back side of the line slowly. Once you have a fairly broad line established, you can open the airbrush up a bit more and fill in the larger areas. Remember your settings, though, as you do not want to try to draw another fine line with your airbrush set wider.
A final step that some might find useful is to lightly sand the entire camouflage with extremely fine sandpaper (4000 grit or finer). This can help smooth out some of those hot spots and provide a better surface for the clear coat. It is not essential, though, and does require some practice to prevent sanding through the colors.
With freehand camouflage out of the way, all the basics of airbrushing are now at your fingertips. These basic skills are all that you need to create beautiful airbrushed subjects, but like every other tool, they require practice. The more you use a tool, the better your results, and the airbrush is no exception. Set aside a handful of models to work as practice subjects and experiment with these various techniques to become more comfortable with your specific system and environment.
The rest of this airbrushing series will build on these basic techniques to demonstrate some of the more advanced finishes that can be achieved through airbrushing.