Silly putty works great with acrylics. The rounder and higher the edge the softer it will be. Murray hit it on the nose, its too easy to use and a couple of "eggs" of the stuff will pay back big in results. Use thin sheets of it to make the hard edges "squiggle" patterns like you see on French and Japanese tanks. (BTW, it may feel oily or seem like it has a film to it, but it doesn't and it won't leave anything on the surface of the model or paint)
You can also hold a piece of torn paper about 1/4" from the surface and shoot past it. That will also create a soft edge.
Most fair to good airbrushes will give you a fine line and should be adequate for most soft edge camo patterns. Try changing the angle of the work piece and shooting upwards (i.e. from the lower edge of where the blue meets the underside white, up towards the top of the plane, or from the edge of the pattern towards the inside of the pattern area). By rotating it and shooting it from the lower side up you will sharpen the edge of the spray cone and reduce overspray spatter. Adjusting flow rate and air pressure as well as distance to surface will also adjust your paint line.
My next piece of advice would be to practice. Pick up some index stock (card stock) and practice making lines with your airbrush, areas of color, blends, fades etc. Roll up a piece of paper or cardstock into a tube and practice shooting it (as if it were a plane fuselage). Inexpensive water paints, guaches or dyes used for the airbrush and practiced with (no matter how mundane it may seem) will again pay off in results and expected results. Once you're comfortable with it, then try the same exercises with model paints. Though it may seem expensive at first, it will be a small price to pay compared to a ruined finsih on your models. Learn the limits of your airbrush and what its capable and not capable of doing. Experiment with different mixtures and air pressures. Keep a notebook or pad so that you can consistently achieve results that you have experimented with to achieve. Some paints may act differently than others. Tamiya acrylics will shoot differently than Modelmaster, than Vallejo etc. (yeah it seems like alot, but it will become second nature before you know it) Once you are familiar with it, you can try out techniques on your models, but more importantly you will understand your airbrush and not expect it to do more than you and it are capable of doing. With practice comes skills, so while you may be limited to simple patterns now, later and with experience will come greater technique and skill to try more complicated and involved designs. "It's not how good the equipment is that you fish with, its how good you fish" my dad told me. And that addage holds true for just about everything.
Good luck.
Mike
Mike
"Imagination is the dye that colors our lives"
Marcus Aurellius
A good friend will come and bail you out of jail...but, a true friend will be sitting next to you saying, "Damn...that was fun!"
