Let us think a little out of the box on this we all came from a plastic models and we when it comes to paint we think Acrylics, enamels and such. But we are working with paper and to me the nearly perfect paint is water colors. Not the little color bricks that come in the $1.98 water color sets but the higher quality paste paint that you purchase in the little tubes. You do not need a 40 color set just Black, white. A couple of reds, a green or two Yellow and the two most important Burnt umber and Yellow Ochre. Michaels crafts will have a 12 color set on sale for around $10 every month or so or use one of their 40% off coupons. As with all model painting get the best brushes and take care of them.
What’s so good about water colors first and foremost you can mix an exact color match to the model and the finish is nearly identical to the printed surface of the model. Once you mix the colors and they dry out just add a little water and you are set to go. With an exact color match painting the crease lines that show white makes them disappear, for edges I color them before I glue up the part. Any glue on the edge of the part will tend to keep the water color from coloring the edge. If you do not match the color exactly and it is darker apply a thin wash of white to the mismatched color and it will blend in to the back ground. The figure painters in the group will recognize this technique.
Some hints for good results add a drop or two of liquid soap to the water this lowers the surface tension and the paint will spread better. Use as little water as possible for obvious reasons. When mixing colors do it on a sunny day out doors for the best match or use the new Compact Florescent lamps that have a color rating of 8500K or higher these lamps have a nearly pure white light (no yellow)
I know the first and the main objection will be, “You use WATER on your models!” this is not a problem as long as you use some common sense. I find that marking pens will bleed the color where you don’t what it and water color pencils do not easily color the edge.
But as I have said before give every thing a try and use what works best for you.
The attached photo is from my current build of the KW Models P-39 the amount of white that would show in the ribbing in the wing and dive brake is quite high. If you look closely there are several areas that need to be repainted and touched up but it is a work in progress. The inset are the throttles and it’s tough to paint the edges with a marking pen when the part is this small.
In the background you can see one of my color trays with the main colors used in this model.
There is a very fine line between paper modeling and mental illness.