You can use the same brush to add the other colors, but the brush must be first cleaned. Pour some paint thinner/cleaner into a disposable pie tin. You don’t need much, just a few teaspoons. Swirl the paint brush in the cleaner and occasionally pull the brush out and wipe the bristles against a clean paper towel. Repeat until no more color can be seen on the paper towel when you wipe the brush.

Follow the same procedure when cleaning brushes after you are done for the day. Store all brushes upright and make sure nothing touches and bristles. Otherwise, the bristles may bend as they dry, and the brush will be ruined.

During manufacture of the model, a type of grease is used to help the parts trees separate from the master metal molds. This grease, called mold release compound, is still on the plastic and must be cashed off before painting. Even if you don’t paint every part of the kit, you should still wash all of the parts.

To prevent the small parts from separating from the parts trees, don’t scrub the plastic to wash it; just immerse the trees in a skink full of warm water. Use a small dab of dish detergent in the water. Let them soak for a minute or so. You can help wash off stubborn release compound by gently stirring the water. Drain the sink and rinse the part sin cold running water. Be sure to keep the water cold because if you use hot water, the plastic will soften.

Place the wet trees on paper towels and let them dry for 15 or 20 minutes. While they are drying, turn the runners a couple of times and gently shake off any excess water. Remember: You can’t paint or cement when the parts are wet, so be sure they are completely dry before starting to build. Also remember that your hands can leave oily deposits on the plastic, so avoid touching the parts as much as possible. Handle the parts trees by the edges.

After washing, carefully inspect each runner. If any parts have come off, collect them and stick them to the face of a strip of masking tape. Use the instruction sheet to identify the part. If the parts are numbered (they usually are), write down the number of the loose part beside it on the tape.

Carefully study the instruction sheet and the illustrations on the packaging box of the kit for the color scheme. You’ll want the model to look as authentic as possible, so you should follow the suggested color schemes as much as you can. Experienced model builders often go to the library to look at books containing color painting and photographs of the real thing (call the prototype by experts). The prototype serves as the definitive or standard color guide for model building.

The color scheme can be more flexible when building model cars, because the real-life prototypes often come in various colors and are often customized by car dealers and car owners. Italian Red is a common color for Ferraris (and all sports cars). You are free to choose any color, but make it a car color. Testor has a full line of metallic pearlescent car color paints. The paints are formulated just like the paint in the real-life cars, and they come in a variety of colors.

Metallic car colors are really semi-transparent, so you’ll need to apply a coat of primer to the car before the finish color. Without the primer coat, the finish coat will not have that opalescent and shimmering quality. Worse, the molded-in color (the color of the plastic parts) may show through the finish color. Applying the primer is a small but necessary step if you want the model to look right.

Hobby paints come in two general finishes: flat and gloss. Flat paint look dull after it has dried, even when it is applied to a shiny surface. The dullness comes from the way the paint dries. If you were to look at the paint close up, you’d see that the surface is very rough. This roughness scatters the light when it hits the paint, so less light is reflected.

The surface of dried gloss paint is smooth, so light is reflected more evenly, like a mirror. That’s why gloss paint looks shiny.

The choice of whether to use flat or gloss paint isn’t always easy. Most cars use gloss paint, but only on the exterior and other parts that are supposed to look bright and shiny. You wouldn’t want to use gloss paint on the interior car seats, for example. Most car seats are vinyl or cloth, so they aren’t very shiny. If you use a gloss paint for these parts, the model won’t look very realistic.

Military models--planes, tanks, trucks, ships, and so forth--are almost never painted with gloss paint. A real plane, painted in gloss paints, would reflect light and the bad guys would spot it easily. If you plan on building and painting military models, use flat paints. U.S. Navy planes are often finished in gloss colors and are an exception to this general rule.

Generally, flat paints dry faster than gloss paints. The weather, the thickness of the coat of paint, and other factors influence drying time, so you have to take these into consideration.

Most paint pigments are opaque, so once the paint is applied in a thick enough coat, the underlying color can’t be seen. The darker the pigment, the more opaque it is. If you are painting yellow over a black background, you will have to apply several coats of black paint over a yellow background before the yellow disappears. This is the reason that if you are using many colors in your model, you should always paint the lighter colors first.

The pigments in metallic paints are transparent, so you can see right through them even when you apply several coats. As mentioned in the previous section, you will usually apply a light primer undercoat so that you see the true color of the finish coat, not the background. For special effects, you can try applying metallic and pearlescent paints over colored backgrounds. The result is an interesting mixture of colors--the translucent finish coat and a tinge of the background.

The small parts are usually easier to paint before you cement the model. If all or most of the parts on a runner are to be painted the same color, you can probably use a spray can to apply the paint. But if the parts are all different colors, or if some of the parts need special painting, you will have to use a brush to apply the paint.

Applying Paint with a Spray Can

The proper way to spray with a spray can is to hold the nozzle 8 to 10 inches from the parts. Aim the can just past the piece to be sprayed. Press down on the spray button. The first squirt of paint will fall on the cardboard. Now, sweep the can from one end of the piece to the other. Move the can at a smooth and moderate pace. Don’t go so slowly that the paint forms puddles when it hits the model and don’t go so fast that only a faint wisp of paint appears. Don’t release the spray button until you are past the piece. You may need to repeat the procedure several times to apply the paint adequately. You do not need thick coating of primer, so go lightly.

Let Dry

Let the primer coat dry thoroughly before handling the pieces. That will take about 24 hours so put the pieces aside and concentrate on painting other parts of the model for awhile. spray the primer on the pieces.

Open the bottle and use a clean toothpick to stir the paint. If the lid of the bottle won’t come loose, use a pair of adjustable plumber’s pliers (sometimes called "water pump" pliers). Be careful not to use too much pressure on the lid or you’ll bend it out of shape, making it even harder to remove. To reduce evaporation, pour only the amount of paint required for the project into a separate container. Recap the bottle after removing all excess paint from inside the cap and outer bottle rim and securely seal for long term storage.

In this section you’ll learn the basics of using both spray and bottle paints to add color and realism to your models. Advanced painting and finishing techniques are covered in greater detail in the easy finishing techniques section and the adding detail section.

Pour a small amount of paint into the tin or palette. Don’t pour in too much or you will waste the paint. Open a bottle of fresh, unused thinner/brush cleaner. Use an eyedropper to pick up a few drops of thinner and squirt it into the paint; then stir it with a wooden stick. Keep adding more thinner until the pain is the consistency you want. Check the consistency by pulling the stick out of the paint. The paint should slowly drip off the stick. If it runs off quickly, it’s too thin. If you add too much thinner, the paint will be too running and will be hard to apply. It is much more difficult to thicken paint than it is to thin it, so add the thinner in small quantities until you get the right mix.

If you don’t have an eyedropper handy, you can use a paper straw to add the thinner (some plastic straws will also work, but beware of some straws that melt in the thinner!). Dip the straw part way into the thinner; then close up the top part with your finger. Being careful not to spill the thinner on anything, transfer the straw to the paint tin or palette. Release your finger and the thinner will come out of the straw. Don’t put the straw too far into the thinner or you’ll get too much. Just one or two drops at a time are all you need.

Some parts don’t come on a runner, or they may become separated from their runner, making painting more difficult. You can use a pair of ordinary tweezers to hold small parts. Avoid tweezers with teeth. The pressure of holding the part can cause the teeth to mark up the plastic. If you can’t avoid tweezers with teeth, glue small strips of felt or cloth to the inside of the tweezers, to act as a kind of cushion for the part.

Your finger may grow tired of pinching the tweezers to hold the part in place. Another alternative is to use locking surgical forceps. These are available from most retail and surplus hobby and industrial supply stores. The forceps are like giant tweezers and they are made with ratchet-locking mechanism. Most forceps have teeth so you should cushion them with felt or cloth, too, as explained above.

You can use a number of other tools to hold parts for painting. A weighted soldering stand, often called a "third hand," has two alligator clips attached to a weighted base. You can place the part in one of the clips and use both hands for painting. Dental picks and tools, also available at most hobby and industrial outlets, let you hold parts for painting. If the part has a hole or crack in it, stick the end of the pick firmly into it. The design of the tool lets you easily rotate the part so that you can paint all of it.

Spray the finish coat as you did the primer coat. Be especially careful of airborne dust--you don’t want any flecks of dust settling on the car as the paint dries. When painting outdoors or in the garage (never spray inside the house), you can prevent dust particles from settling by using a "paint booth." This is merely a large cardboard box that acts to protect the model against dust and wind.

Place the model in the box and apply the spray. Cardboard is fairly dusty, so before painting use a spray bottle to wet down the inside of the box. Use a piece of coat hanger or other stiff wire to hang the model pieces.

With all paints, but especially with spray paints, it is better to apply several thin coats rather than one thick coat. The paint job will look a lot nicer and the paint won’t puddle up on any of the parts. The penalty of applying thin coats is that you have to wait for the paint to dry before respraying. Wait the usual 12 to 24 hours between coats and wipe down the model with a clean, lint-free cloth to get rid of any dust before you apply more coats. Experienced model builders like to use sticky "tac rags" for this. Tac rags are available at most lumber and hardware stores.

After the paint is dry, assemble the kit as indicated in the instruction manual. Remove the parts from the runners as discussed in "Model Building Using Cement." Model cement won’t stick to parts that have been painted. Therefore, you will need to remove the paint from the cement joints prior to cementing. If you don’t remove the paint, the cement will cause the paint to soften and you’ll have a gooey mess.

You can remove the paint from the joining surfaces of the parts in any of several ways. The easiest is to use a small file or piece of sandpaper. File or sand the piece until the paint is removed. Back the sandpaper with a small block of wood. Hold the p per in place with your fingers or attach the paper with double-stick tape.

Remember not to remove any of the plastic underneath the paint, especially if the mating joints must fit into one another snugly. If you take off too much plastic on an alignment pin, for example, it may fit sloppily into its mating hole, and the model won’t be as strong. Go slowly.

Another way to remove the paint is with a technique called "adzing." With adzing, you scrape the excess paint off the part with a hobby knife, much the same way you clean the scales off fish with a fishing knife. You must be careful when using the adzing technique, because there is a chance that the knife can slip and cut your finger. The duller the knife the better, so it’s okay to use an old, worn-out blade.

To adze the paint off a part, cock the blade so that it’s almost perpendicular to the surface of the piece. Apply light pressure and draw the blade toward you. You will have to go over the spot several times before all the paint is off. If the part is round, don’t go over the same spot twice. Move the blade each time so you don’t create a "flat"--an indentation caused by over-adzing.

If the pieces are large, you can remove the layer of paint with extra-fine steel wool. As with the other methods, avoid removing any of the plastic. Discard the steel wool when it become full of dry paint.

Liquid cement should never be applied to painted surfaces because the paint will run. And you should always apply the cement to the inside of the parts (when possible), so any cement marks won’t appear on the outside of the model.

Any solvent that will remove the cement from a polystyrene model will also destroy the model; however, nail polish remover that contains acetone will remove the cement. Blot at affected area, taking care not to smear.

You apply epoxy the same as you do white glue, except that you must first mix epoxy together. Squeeze out an equal amount from each tube and swirl it together with a toothpick. After the two parts are thoroughly mixed, apply the epoxy to the model. Unused mixed epoxy must be thrown away. You can’t place the mixture in a bottle and store it for later use.

Decals can be successfully applied to any gloss finish paint, but you may want to apply Glosscote for an even smoother surface. The smoother the surface, the better the decal will set. Follow the instructions given in the last chapter on how to apply decals. Remember to wait at least two or three days before applying decals to a painted model. You must be sure the paint is thoroughly dry and set.