Do RC Cars Run on Water?

Last Updated on December 8, 2023 by Jaxon Mike

RC (radio-controlled) cars are a popular hobby for enthusiasts around the world. These miniature vehicles are operated remotely using a specialized transmitter that sends signals to a receiver inside the car.

This allows the user to control the car’s speed, direction, and other functions. But can you take your RC car for a drive across the water? Let’s take a closer look at whether RC cars can operate on water.

How Do RC Cars Work?

To understand if an RC car can run on water, you first need to understand how they work on land. RC cars are powered by small electric motors or gas engines. The motor turns the wheels and propels the car forward.

Most RC cars have two or four-wheel drive. Some even have functional differentials, suspensions, gears, and shocks – just like real cars!

The motor and steering are controlled by the transmitter. When you turn the steering wheel on the transmitter, it sends a signal to the servo motor connected to the front wheels telling them which way to turn.

The throttle trigger controls the speed of the motor. All of this is powered by a rechargeable battery pack inside the car.

Challenges of Running RC Cars on Water

So in theory, an RC car should be able to run on water if the wheels can gain enough traction. However, water provides much less traction than solid ground. The tires will tend to spin on the surface rather than propelling the car forward.

Another issue is buoyancy. The weight of the car is supported by the ground when running on land. But on water, the car’s weight may cause it to sink if it doesn’t displace enough water. The minor waves created as the car moves through the water will also work against its progress.

Modifications Needed for Water Travel

Some creative RC enthusiasts have found ways to modify their cars to enable water travel. Here are some of the main approaches:

Larger Tires

Fitting larger, paddle-style tires gives more surface area to grip the water. These tires are similar to those found on amphibious vehicles. They provide more flotation and traction compared to normal RC tires.

Sealing the Electronics

The electrical components like the battery and servo motors need to be sealed so they don’t get immersed in water. Waterproof cases will prevent short circuits and damage.

Floatation Devices

Adding extra buoyancy helps compensate for the car’s weight. Small floats can be attached to the front and rear. Larger pontoons will give even more lift.

Water Propulsion

For the ultimate RC water car, add a propeller and rudder to supplement the wheels. The propeller provides forward thrust in the water while the rudder steers. This turns the car into a radio-controlled boat when traveling across water.

DIY Water-Running RC Cars

Many hobbyists have taken on the challenge of creating a DIY RC car that can run across water. This involves waterproofing the electronics, adding floats for extra buoyancy, and fitting paddle tires to the wheels.

With some trial and error, these modified RC cars can successfully skim over small bodies of water like a pond or pool.

But handling wakes and waves are still an issue, so performance may not match expectations. Here are some examples of inventors who managed to get their RC cars driving on water:

• A team of students from UC Berkeley used pontoons and a four-paddle-wheel design to create a crafty water-straddling RC car.
• Mark Rober, a NASA engineer turned YouTube star, modified an off-road RC truck with inflatable pool floats to tackle his hot tub.
• Mechanic maestro Adam Savage fabricated enormous pontoons to keep his large-scale RC car from sinking in a lake.

Commercially Available Amphibious RC Cars

While homebrew water-running RC cars are fun projects, specialty manufacturers have also created commercially available amphibious models:

• Tamiya MadBull – This bulky design is meant for high-speed water operation with its fan-powered pontoons.
• Radio Control Boat Model S100 – Despite the name, this RC boat can operate on land too thanks to its four-wheel drivetrain.
• AquaCraft Rio 51 – Featuring both a marine propeller and grippy tires, this versatile RC machine transitions from land to water driving.

These products prove that with the right modifications, RC cars can motor over water for short distances. But expect limitations in handling and speed compared to land.

Practical Uses of RC Water Cars

Amphibious RC cars have some niche applications despite their drawbacks:

• Exploring – Drive over rivers, lakes, or marshes to scope out the terrain.
• Retrieval – Collect small floating objects in ponds or pools.
• Racing – Test your modified RC car’s water-crossing abilities against others.
• Entertainment – Enjoy the novelty of running your car where it shouldn’t go.

Most RC enthusiasts pursue the water-running challenge just to see if they can and have fun experimenting. But for serious RC use, cars optimized for land or water separately remain ideal.

Key Considerations Before Running an RC Car on Water

If you want to make your RC car amphibious, keep these tips in mind:

• Start with a water-resistant chassis – avoid open-frame designs.
• Waterproof all electronics inside to prevent electrical damage.
• Add lightweight floats or pontoons for extra buoyancy.
• Choose wide, paddle-style tires for traction and flotation.
• Consider supplemental propellers for propulsion if needed.
• Test in very shallow and calm waters first.
• Expect reduced speed, maneuverability, and run time compared to land.
• Be prepared to make design adjustments through trial and error.

Frequently Asked Questions

What types of RC cars can run on water?

With the right modifications, most four-wheel drive RC cars can be made to traverse calm water for short distances.

Trucks tend to work better than low-profile cars thanks to more clearance and better weight distribution. Amphibious RC cars designed for both land and water operation are also available.

Do I need to waterproof my RC car to run it on water?

Yes, you’ll absolutely need to waterproof the electrical components to prevent shorts and damage. The battery, servo motors, receiver, and any other electronics will need to be sealed up with a waterproof casing or marine-grade protective coating.

Can I just drive my normal RC car into a lake?

It’s not advisable to run a stock RC car right into a body of water. It will likely short circuit and get damaged very quickly. Modifications like waterproofing the electronics and adding floats are needed to have any chance of it working on water.

What size floats do I need for an RC car to run on water?

Small cylindrical floats about 2-3 inches in diameter can be attached to the front and rear of the car. For better lift, install larger rectangular or cylindrical pontoons that run along the side of the chassis. Their size depends on the weight of the car – aim to displace around the same volume of water as the car’s weight.

Is it possible to 100% waterproof an RC car?

A truly waterproof RC car is difficult to achieve, especially for the moving parts. Special marine grease can help protect the gears, bearings, and axles. Use conformal coating or potting compound to waterproof the delicate electronics.

O-rings, gaskets, and seals will also prevent water intrusion into the chassis. But it’s tough to guarantee no water penetration, so care is still required when running in water.

Can I drive my RC car underwater?

RC cars are not designed for full underwater operation. While the electronics can be waterproofed, the tires will not be effective and the car will lack propulsion force. The engine or motor will also not work properly submerged. RC submarines with propellers are a better choice for underwater driving.

How fast can an RC car go on water?

RC cars driving on water will go much slower than on land – typically 5-15 mph is the maximum speed range. Traction is limited, so acceleration and handling also suffer. If equipped with a supplementary marine propeller, the speed may be improved, but still well below land speeds.

What motor is best for an amphibious RC car?

Electric brushless motors have some advantages for RC water cars compared to nitro/gas motors. They are sealed against water, provide instant throttle response, and have simpler waterproofing needs.

Brushless motors also provide ample power in a compact unit. Just be sure to waterproof the rest of the power system too.

Can saltwater damage an RC car?

Freshwater is gentler on RC cars than saltwater. The salt can cause corrosion of metal components and clog moving parts over time. Ensure proper waterproofing and lubrication. Thoroughly rinse the car with freshwater after use in saltwater. Avoid saltwater operation as much as possible to extend the lifespan of your RC car.

Where is the best place to run an RC car on water?

Calm, confined bodies of water work best for RC cars, like a small pond, pool, or puddle with minimal waves. Stay close to shore in case you need to retrieve the car. Small creeks, inlets, or other sheltered areas are also good test spots. Open water with potential boat traffic is riskier. Practice in bathtubs or kiddie pools at first.

Can I drive my RC car in the ocean?

It’s not recommended to run RC cars in the ocean. The waves, swells, potential tide changes, and saltwater will quickly overpower and damage the car. RC boats built specifically for ocean use are a better choice. Leave the RC car fun to small ponds and lakes.

Do I need to register an RC water car?

You generally don’t need to register RC vehicles, including water-running models. But do check your local state laws if operating in public waterways. For example, a gas/nitro powered RC car over 10hp would require registration as a motorboat in Minnesota. Always exercise good judgement too when running RC vehicles around others.

Is it illegal to drive an RC car in public waters?

The legality depends on the laws in your area, but it’s usually not permitted to operate RC vehicles on public lakes, rivers, etc. They can pose risks to others on the water and create a nuisance. Find a private pond or pool instead. Some RC enthusiasts have reported fines for illegally operating RC vehicles on public waterways.

Can RC cars go in the rain?

Driving RC cars in light rain is generally fine since most have some basic weatherproofing. But take precautions like limiting operation time and avoiding deep puddles that could splash inside the chassis. Properly waterproofed RC cars will withstand wet conditions much better. Always dry them off and allow components to air out afterward.

Is it possible to build an RC car that drives on land and transforms to work on water?

With some very creative engineering, it is possible to create transforming RC vehicles. The key is making the modifications quick and reversible – detachable pontoons or deployable propellers, for example. But in most cases, optimized separate machines for land and water remain simpler and more effective.

Conclusion

While not without limitations, RC cars can be modified to drive over relatively calm water with additions like pontoons for flotation, waterproof casings for electronics, and paddle-style tires for traction. It makes for an exciting engineering challenge for hobbyists.

For casual, short-term fun, water-running RC cars provide enjoyment. But for performance driving, purpose-built vehicles designed specifically for land or water operation are still optimal choices.

With creativity and patience, transforming RC machines to traverse both terrains can be achieved as well. For those seeking a thrill and in search of their next project, making an RC car skim across the water’s surface brings endless experiments and rewarding successes when you finally get it maneuvering over the lake.