RC cars are designed for speed and performance, but their plastic bodies are vulnerable to cracking and breaking under the stresses of racing, jumps, and crashes. Reinforcing the body with materials like carbon fiber and fiberglass is a great way to improve durability and protect the electronics inside. In this guide, I’ll cover the reasons you may want to reinforce your RC car body, the materials needed to do it properly, the step-by-step process, and some tips for getting the best results. Whether you bash your RC car hard or are looking to bolster the body against impact, reinforcement is an easy upgrade that can extend the life of your car and maintain its performance. Read on to learn everything you need to know about properly reinforcing an RC car body.

1. Reasons to Reinforce Your RC Car Body

How To Reinforce RC Car Body?

Improve durability

Reinforcing the body of your RC car with materials like carbon fiber or fiberglass can greatly improve its overall durability. RC cars are often subjected to intense stresses from jumps, crashes, and general racing or bashing. The plastic material that makes up the outer shell can crack, bend or break over time. Adding a reinforced layer underneath helps absorb impact and stress, preventing damage. It protects the body from developing cracks or holes from small crashes that would ruin an unreinforced shell. A reinforced body can take much more abuse before needing to be replaced.

Protect electronics

The electronics inside an RC car, like the motor, ESC, receiver and battery can be expensive to repair or replace. When the outer shell suffers damage in a crash, it also exposes the sensitive electronics inside to damage as well. They can be directly impacted or exposed to the elements like dirt or water. Reinforcing the shell helps prevent this damage in the first place by making it more rigid and impact resistant. Electronics will be protected even in minor crashes that might normally crack the body. The reinforced shell keeps everything protected inside so you avoid expensive repairs.

Maintain performance

When an RC car body starts to suffer cracking or warping from repeated stresses, it can negatively affect the car’s overall performance. The cracked shell is more flexible, which allows more chassis twisting. This reduces responsiveness and speed. Extra flexing also causes more variability in how the car handles, making it harder to control. A reinforced body maintains its rigidness and shape over time. This leads to more precise and consistent handling with better cornering and more stable high-speed runs. The level of performance stays consistent for longer compared to an unreinforced shell.

2. Materials Needed to Reinforce RC Car Body

How To Reinforce RC Car Body?

Carbon fiber sheet

Carbon fiber sheets made of woven carbon fiber cloth are a great option for reinforcing RC car bodies. The carbon fiber material is very stiff and rigid, yet also lightweight. This helps add strength without significantly increasing weight. Carbon fiber sheets can be easily cut and shaped to fit the contours of the RC body. High-quality carbon fiber cloth with good weave density provides the most reinforcement. Uni-directional carbon fiber is also available but may be more difficult to work with.

Fiberglass sheet

Fiberglass sheets are another good reinforcing material option. They are affordable and easy to work with using basic tools. Fiberglass provides good impact resistance and stiffness. It can be purchased in various cloth-style weaves and weights. Standard fiberglass cloth works well for RC applications. Avoid super heavy/dense weaves as these will add unnecessary weight. Fiberglass is not quite as strong or rigid as carbon fiber but still provides good reinforcement at a lower cost.

Epoxy resin

An epoxy resin is required to saturate and hold the fiberglass or carbon fiber sheets to the RC body. Epoxy cures to a hard, durable finish that bonds well to plastics. A two-part epoxy must be mixed precisely as directed and used within its working time. Quick-set 5-minute epoxies allow you to complete the reinforcement project faster. Make sure to use an epoxy safe for modeling applications.


Sharp scissors are needed to accurately cut the fiberglass or carbon fiber cloth to shape before adhering it. Dedicated scissors just for carbon fiber are recommended to avoid dulling other scissors. The reinforcing material can be cleanly cut to fit curved areas of the RC body.


Various grit sandpaper (180, 220, 400) is required to scuff and prep the body shell for reinforcement. It is also needed later to smooth the edges of the applied reinforcing material so it blends seamlessly into the body. Sanding blocks help for even sanding.

3. Steps to Reinforce RC Car Body

How To Reinforce RC Car Body?

Clean and prepare the body

Thoroughly clean the inside of the RC car body shell with soap and water to remove any dirt, grease or oil. This allows the epoxy resin to properly adhere. Use a sanding block with 220 grit sandpaper to scuff the interior of the body. This roughs up the smooth plastic so the epoxy can grip. Pay special attention to sanding the areas that will have reinforcing material applied. Wipe away any dust with a tack cloth.

Cut reinforcing material to size

Make paper templates first to get the sizing and shape needed for each piece of reinforcing fabric. Trace the templates onto the carbon fiber or fiberglass sheet. Use sharp scissors to carefully cut each piece out. Cut the material just a bit oversized so you can trim for a perfect fit on the body later. Cut small relief notches in areas that contour and bend.

Apply epoxy resin

Mix a small batch of two-part epoxy resin per the instructions. Apply a layer of epoxy using a foam brush over the area of the body that will receive the reinforcing material. Quickly place the cut out carbon fiber or fiberglass piece into the epoxy. Use the brush to wet out the material completely with epoxy until it is fully saturated.

Attach material to inside of body

Once saturated, press and smooth the reinforcing piece firmly so it adheres to the interior of the RC body. Avoid trapping air bubbles. Use masking tape strips to help hold the material tightly in place as the epoxy begins to cure. Slowly go over all areas and trim off any excess material with scissors for a clean finish.

Smooth edges

As the epoxy cures, use a sanding block with 400 grit sandpaper to sand the edges of the applied reinforcing fabric. Blend and smooth the edges so no ridges are felt for a seamless look. Be careful not to sand all the way through the material.

Apply finish coat

Mix another small batch of epoxy and apply a finish coat over the entire reinforcing piece and surrounding area. This seals the weave and bonds everything together into one solid piece. It provides extra strength and a glossy finish. Allow the finish coat to fully cure before handling.

Sand and paint

Once fully cured, wet sand the entire body with fine 600 grit sandpaper to prep it for paint. This removes any protruding fibers and provides a smooth surface profile. Clean and paint the body shell per your desired paint scheme to complete the reinforcement process.

4. Tips on Reinforcing RC Car Body

How To Reinforce RC Car Body?

Focus on high-stress areas

To optimize the reinforcement, focus applying the carbon fiber or fiberglass to the areas that get subjected to the most stress and impact. This includes the front and rear ends, sides, and any thin panels prone to bending. Reinforcing just these key zones helps strengthen where it’s needed most without going overboard.

Don’t overdo it with weight

While reinforcement does add strength, it also adds weight. Too much additional weight can bog down the acceleration and handling. Apply the reinforcing material selectively in thinner sheets and only critical areas. Use lighter weaves if needed. Keep weight gain to a minimum for best performance.

Work slowly to avoid air bubbles

Working slowly and methodically is key to avoid trapping air bubbles in the epoxy resin. Bubbles lead to weak spots so take your time when saturating the fabric. Use a brush to fully wet out each piece and gently smooth over it as you apply it to the body. Pause to pop any visible bubbles using a toothpick.

Let epoxy cure fully before handling

It’s critical to allow the full recommended cure time with epoxy before doing any sanding or handling of the reinforcement job. Insufficient curing will allow the material to shift or delaminate, ruining the hard work. Be patient and wait the full cure time before touching or painting the body.

Final Thoughts

Reinforcing the body of your RC car by adding a layer of carbon fiber or fiberglass cloth can significantly improve its durability and lifespan. This simple upgrade helps protect the body from cracking or bending on impact, while also protecting the electronics inside. By following the steps outlined, you can reinforce key high-stress areas to make your RC car more rigid and impact-resistant. Just be sure to work slowly with the epoxy resin to avoid bubbles and allow full curing time before handling. With a reinforced body, you can drive your RC car harder, take bigger jumps, and bash with confidence knowing it can handle the abuse. The body will maintain its shape and last much longer before needing replacement. If you regularly use your RC for racing or bashing, reinforcement is a smart way to boost its strength while keeping weight gain minimal.

Enjoyed this guide of How To Reinforce RC Car Body? Then be sure to check out our other RC Rating guides.