Further, lithium-polymer batteries are free from inherent performance degradation problems that Ni-MH packs have. First consideration with a lithium-polymer battery pack is the C rating, which refers to the amperage-discharge capability of a particular battery. A higher-rating battery pack can handle more load without any issue.
Battery charger. From the battery pack for handheld starters to the receiver pack, having a good battery charger can make it easier to run the boat. Although timer chargers and peak detection chargers are available for RC boats, the latter is recommended for better results.
A timer charger will save you money but a peak-detection charger, also known as peak charger, costs a little more and features advanced charging algorithms to ensure that the battery pack is brought to a complete charge safely.
ESC. Many of the latest RC boat model kits include a programmable ESC. The programming feature allows alteration of the cutoff voltage of the ESC to protect the battery pack from over-discharging. The enhanced option to programme the ESC through the use of an ESC programming module (EPM) will also make it possible to activate braking, set cutoff preferences and choose throttle curves.
These days it is easy to buy DIY kits for RC boats from many online vendors. Independent spare parts for these boats are also available at affordable rates. If you want to drive a boat but you do not have access to a wide area of open water, a mini boat kit is an option. It is smaller than other boats but features similar handling and performance characteristics of its larger counterparts.
These mini boat DIY kits require very little preparation time to get on the water and provide an inexpensive way for someone to get their hands wet in the world of RC boat modelling. Whether it is a minor kit or a major one, there should be a small plastic bag that includes a basic assortment tool kit, in addition to the boat kit. The tool kit comes in most popular sizes used in RC world, and you will realise its value the first time you use it.
Water cooling. Water-cooling technique is widely used to keep the motor and ESC running relatively cool. The components are wrapped with coils of aluminium tubing, and the coils are connected with flexible tubing to a water pickup at the bottom of the hull. As the boat moves forwards, water is forced into the pickup and through the coils to provide conductive cooling of components.
Fig. 8 shows the inside view of a brushless DC motor (BLDC) based RC boat with an effective water cooling system.
Before you run your finished boat for the first time, you should lubricate the main propeller shaft with plenty of marine grease. This not only helps seal the flex shaft tube better, preventing water from seeping into the hull, but also reduces friction. If the canopy is not sealed properly, water may seep in to the hull. So, remember to seal off the area between the canopy and the hull itself using flexible clear tape or a similar high-quality adhesive tape.
Similarly, ESCs and radio receivers used in boats are highly water-resistant. However, extra steps to better seal off the electronics will help these live longer down the water.
Finally, use fresh batteries in the radio transmitter and a fully-charged battery pack in the boat.
RC boat modelling is a great hobby. Through this basic guide you can make sure your RC boat is set up properly to maximise fun and minimise down time. Well, just roll up your sleeves and prepare your boat for the water. Get ready to make some good waves!
Warning! Since RC boats are not designed as flotation devices, retrieval of a stalled RC boat is not an easy task. Never attempt to swim after a stalled RC boat. Do not get in the water for any reason to retrieve your boat. Always use a personal flotation device (PFD) for retrieval.
T.K. Hareendran is an electronics hobbyist, freelance technical writer and circuit designer