How to Paint and Finish Your Remote-Controlled Car Body

For many RC enthusiasts, the chassis, the electronics, and the raw speed are the primary obsessions. But for the true artist of the radio-controlled world, the car's body—the shell—is the canvas. It’s the first thing you see, the identity of your machine, and a point of immense personal pride. A professionally finished body transforms your RC car from a toy into a showcase model. In this comprehensive guide, we’ll dive deep into the art and science of painting and finishing an RC polycarbonate (Lexan) body. We’ll pay special attention to a critical, often-overlooked component that directly influences your design choices and finishing process: the humble yet mighty micro servo motor.

Why the Micro Servo Motor is Your Design’s Starting Point

Before you even dream of paint schemes, you must understand the role of your micro servo. This compact powerhouse is responsible for your car’s steering. Its size, mounting location, and the geometry of its servo saver (the arm that connects to the steering linkage) have massive implications for your body shell.

• Clearance is King: A micro servo, especially a standard or low-profile one, occupies space under the front of the body. A body shell with an extremely low, sloping front end (think Lamborghini prototypes) might not fit over your servo and its linkages. You must perform a "dry fit" of the unpainted body onto your fully assembled chassis to check for physical interference. Mark these areas with a dry-erase marker.
• The Servo Saver Sweep: When you turn the wheels fully left and right, the servo saver arm swings in an arc. This arc must be completely clear inside the body. Failure to account for this will result in the saver grinding against the interior paint, causing chips and, worse, binding your steering.
• Ventilation Considerations: High-torque micro servos can generate heat during intense use. While not usually a primary concern for cooling, a tightly fitted body with no airflow can contribute to overall electronics heat buildup. Strategic window cuts or small vents in inconspicuous areas can help.

The Takeaway: Your paint design must work in harmony with the mechanical reality beneath. A stunning, intricate design on the hood is pointless if you have to cut a giant hole in it to clear your servo horn.

Phase 1: Preparation – The Foundation of a Flawless Finish

A perfect paint job is 80% preparation. Rushing this phase guarantees tears later.

Gathering Your Arsenal

You will need: * RC Polycarbonate Body: Clear, unpainted. * Lexan-Specific Paints: Tamiya PS (Polycarbonate Spray) series is the gold standard. Do not use regular hardware store spray paint—it will not adhere properly and will crack. * Design Tools: Liquid mask, masking tape (Tamiya masking tape for curves is excellent), sharp hobby knives (X-Acto), scissors, and permanent markers for outlining. * Surface Prep: Isopropyl alcohol, lint-free microfiber cloths. * Finishing Touches: Body reamer/drill for post-painting holes, lexan scissors, decal softener/setter (optional but recommended).

Step-by-Step Prep Work

1. Wash and De-grease: Remove the protective film from the inside of the body (this is the surface you paint!). Thoroughly wash the inside with warm, soapy water, then wipe down with isopropyl alcohol. Handle only by the edges to avoid fingerprints.
2. Cutting Out the Body: Use sharp lexan scissors to roughly cut the body from its main sheet. Leave a generous margin. Then, carefully follow the final trim lines. It’s easier to trim more later than to fix a cut that’s too deep.
3. Drilling and Piercing Holes: DO NOT DRILL MOUNTING HOLES YET. You will do this after painting to ensure perfect alignment. However, you should pierce small pilot holes for things like antenna mounts or roof vents if they are in non-stressed areas.
4. The Critical Dry Fit: Mount the body to your chassis using temporary clips or tape. Check for servo, shock tower, and tire clearance at full compression and steering lock. Mark any areas of contact. This is your last chance to modify the shell before paint.

Phase 2: Design and Masking – Where Vision Meets Precision

This is the creative heart of the process. Your approach here depends heavily on your skill level and ambition.

Conceptualizing Your Design

• Keep it Simple for Your First Body: Bold stripes, two-tone schemes, and simple geometric patterns are forgiving and look great.
• Draw It First: Use a dry-erase marker to sketch your design directly onto the outside of the body. Remember, you are painting from the inside, so your layers will be applied in reverse order. The first color you spray will be the top detail on the outside.

Masking Techniques for Complex Effects

1. Liquid Mask for Complex Curves: For areas with complex curves (fender flares, hood scoops, intricate shapes), painting liquid mask is a lifesaver. Paint it over the entire area you wish to protect, let it dry completely (it becomes a rubbery film), then use your hobby knife to carefully cut and peel away the mask from the areas you want to paint first.
2. Precision Tape Masking: Use tape for straight lines and long curves. Burnish the edges of the tape down firmly with a toothpick or the back of your hobby knife blade to prevent paint bleed.
3. The "Backing Color" Rule: Always plan your color sequence from the outside-in. If you want bright green flames over a black background, you must paint the flames first, then cover them with mask, then spray the black. The black becomes the "backing" that makes the flames pop.

Phase 3: Painting – The Art of Layered Light

Painting lexan is a unique process because light interacts with the translucent plastic and the paint from behind.

The Painting Environment

• Warm, Dry, and Dust-Free: Paint in a well-ventilated area (a spray booth is ideal). Ensure the body and paint cans are at room temperature.
• Shake, Shake, Shake: Shake your Tamiya PS can vigorously for a full two minutes after the mixing ball rattles freely.
• The Golden Rule: Multiple Light Coats: Never try to cover in one heavy coat. It will run, obscure detail, and take forever to dry.

Application Process

1. First Color Application: Hold the can 8-10 inches away. Apply the first color in a light, even "dusting" coat. This acts as a primer. Let it dry for 10-15 minutes. Apply 2-3 more light coats until you achieve solid, even coverage. Allow at least 30 minutes of drying time before considering the next masking step.
2. Masking for Subsequent Colors: Once your first color is dry to the touch, apply your masking for the next color. Be meticulous with seal edges. Apply your next color, again in light coats.
3. The Final Backing Coat: After all your design colors are applied and fully dry, it is essential to apply a backing coat. This is typically white, silver, or black.
   • White/Silver: Makes fluorescent and light colors (yellow, orange, light blue) incredibly vibrant. It reflects light back through the paint.
   • Black: Creates a deep, rich, and opaque finish. It kills light transmission, making colors appear darker and more metallic. It’s excellent for creating shadows and depth but can mute bright colors.
4. Drying and Curing: Let the body cure for a minimum of 24 hours in a warm, dry place before handling for final assembly. The paint will continue to harden over the next few days.

Phase 4: Final Assembly – Marrying Beauty and Beast

Now, your painted shell is ready to meet the chassis—and its micro servo—for the final time.

Post-Painting Body Modifications

1. Cutting Ventilation and Cooling Holes: If you’re running a high-stress setup, consider cutting small, neat holes behind windows or in the rear windshield to allow heat from the motor and ESC to escape. Use a body reamer or a sharp hobby knife.
2. Drilling Mounting Holes: This is the most nerve-wracking step. Place the body perfectly on the chassis. Use a sharp drill bit or body reamer to slowly pierce the body from the inside out at the center of each post. This minimizes paint chipping on the exterior.
3. Installing Body Accessories: Mount your interior wing, mirrors, and light buckets (if used) according to the kit instructions. Use lexan-safe glues (like shoe goo or specific poly cement) for permanent attachments.

Final Fit and Micro Servo Clearance Check

Before you secure the body with all clips, perform one last comprehensive check. * Re-attach the body and slowly turn the steering from lock to lock. Listen and feel for any scraping or binding. * Compress the suspension fully. Ensure the tires don’t rub against the freshly painted wheel arches. * Verify that the body posts don’t put undue stress on any single point of the shell.

Applying Decals and Details

• Soapy Water Method: For large, complex decals, mix a drop of dish soap in a spray bottle of water. Spray the area, apply the decal, and you can slide it into perfect position before squeezing out the water and sealing it.
• Decal Softener: Use a decal softener (like Micro Sol or Tamiya Mark Fit) to help decals conform over complex curves and rivet details, making them look painted on.
• Final Protective Coat (Optional): Some modelers apply a very light coat of clear polyurethane spray (designed for lexan) on the outside to protect decals and add a uniform gloss. Test on scrap first!

Advanced Tips: Elevating Your Paint Game

Once you’ve mastered the basics, the world of advanced techniques opens up.

Fade and Candy Effects

• Fades: Achieved by spraying your primary color lightly at the starting point, then gradually moving the can further away or reducing pressure as you move across the body. Practice on a spare soda bottle first!
• Candy Colors: These are transparent colors over a metallic base (usually silver or gold). The metallic base provides the sparkle, and the candy color layer provides the hue. The result is a deep, luminous finish.

Using an Airbrush for Ultimate Control

For unparalleled detail and complex color gradients, an airbrush is the tool of choice. You must use airbrush-specific polycarbonate paints (like Createx Wicked Colors with a polyurethane reducer). This allows for intricate flame jobs, realistic weathering, and photorealistic details impossible with a spray can.

Lighting Integration and the Servo Link

With the proliferation of micro LED kits, adding functional headlights and taillights is popular. When planning this, consider wiring routes. Often, the steering servo area is crowded. Neatly routing light wires away from the servo saver’s path is crucial to prevent snagging and servo failure. Use small zip ties or adhesive-backed wire clips to secure wiring along the chassis, not the body.

The journey from a clear polycarbonate shell to a rolling work of art is one of the most rewarding aspects of the RC hobby. It demands patience, planning, and a respect for the interplay between form and function—epitomized by the need to design around the hard-working micro servo motor. By following these steps, you’re not just painting a body; you’re crafting an identity for your machine, ensuring it stands out in the pits and performs flawlessly on the track. Now, go grab that can of paint and start creating. Your canvas awaits.