Radio and receiver

I'm a huge fan of the Flysky FS-i6 series. The i6 and i6X are mechanically identical; the i6X firmware just supports up to 10 channels. Turnigy rebrands these and resells them too, so check Hobbyking's price before you pay for the name brand.

• Receiver: the FS-iA6B is my favorite. It's easy to waterproof: fill the clamshell case with E6000 and screw it closed again.

• Buttons: Shipkicker's plug-and-play button conversions drop into the FS-i6 and Turnigy Evolution Pro.

Power: every component gets its own battery

I've moved away from wiring harnesses. Every component gets its own battery, or two batteries on a parallel harness when it needs more capacity. BEC failures cause the overwhelming majority of boat fires. I haven't had a boat fire or a smoked component since I started doing it this way, knock on wood.

• Receiver: its own small pack. Many brands sell small NiMH packs specifically for receiver power applications. These can be found on Amazon all day long.

• Servo: Powered by the receiver's power bus from the receiver battery. I don't use BECs specifically because of servos. If one starts to fail, it can overload the BEC and cause an ESC fire.

• Drive ESCs: each on its own 3S pack (or pair). Never use the BECs.

• Pumps: paired 3S 5200 mAh packs on their own. The pump is about 70% of your boat's power use, so nothing shares with the pump batteries.

• Gun boards: tap power from a drive battery with an inline XT60 tap, or give them a small pack of their own. I've done both.

It's easier and faster to build, and it's redundant: a dead battery or a short takes out one component, not the whole boat. It's also diagnostic: if one shaft's batteries come back much lower, something's wrong on that shaft. Don't swap every pack every sortie. Check voltages between sorties and change what's low; on my Indiana that meant the pump packs once per battle.

Pumps

The SJS Pump V3 is a 3D printed kit. It takes 19 mm or 25 mm motor bolt patterns (25 mm with a recess for a brushed motor's end bell), comes with a vertical or 45° outlet, and has the restrictor (1 unit, 1/2 unit, etc.) built in. Paired with a 2400kv Tenshock inrunner on 3S, you get 3+ gallons per minute out of the box in a 1 unit application.

• Pump ESC: a brushless pump ESC like the Hobbywing Skywalker 60A (pot it yourself). On 4S LiFe, set the pump ESCs to NiMH mode, or their low-voltage cutoff will throttle the pump while the battery is still full. On a normal LiPo boat, set the voltage cutoff to what you feel is a safe cutoff point. Some people run with no LV cutoff, this is a risky trade. Obviously you don't want your pump dying in battle, but you also don't want to permanently damage a LiPo pack by over-drawing it.

• Plumbing: the hull outlet is 9/16" OD .014 wall brass to take a 1/2" OD vinyl tube. The tube into the pump body is 13/32" OD .014 wall brass, a tight fit inside the vinyl.

• Placement: keep pumps on the centerline (when she lists, the pump on the high side does nothing). Keep about 6" between pump motor shafts. Our boats spend 40% of their lives reversing, and most ships have volume in the bow, so a bow and stern pump is worth trying.

• Priming: SJS hulls have water channeling that runs to the pump sump. If the boat lists and the water sloshes to one side, the pump never primes. Add channeling, and space the pump a hair off the hull so it doesn't vacuum itself down. The water channel in the hull is what I consider the bare minimum required for a combat hull. You may find that you want to add more foam/filler/etc to try and keep water from collecting in specific spots. That's your call.

• Maintenance: Tenshock motors use 625ZZ bearings at about $0.15 each. Swap them once a year and fog the motor with WD-40 after every event. On your first bearing swap, drill a hole in the top plate so you can oil the top bearing without taking the motor apart.

Keeping water out

• Deck seal makes or breaks a boat. Following Kevin P.'s testing, I smoke-test my boats to near air-tight. I gasket the decks with Permatex The Right Stuff and keep through-deck holes to a minimum.

• Deck retention: magnets are nice, but nothing beats screws for sealing. SJS hulls with mechanical retention have 4-40 heat-set inserts; swap the button heads for stainless knurled thumb screws if you like. If you ever go "Man, this is a crapload of magnets! Why so many magnets Will??" it's because your deck seal needs compression to truly work. Those magnets need to squeeze the deck seal gasket to actually seal up tight.

• Electronics: pot anything not factory-waterproof in slow cure epoxy. Do it after you've tested it.

• Switches: cheap SPST rockers for gun tweaking, packed with dielectric grease. Simple exposed contacts, not much to fail.

• Leak test the hull before your first battle. There's always at least one spot that needs a dab of CA.

LiPo care

• Balance regularly, not necessarily every charge.

• After an event, run packs down on a dedicated discharger (I use ISDT), then storage-charge with a balance.

• Check balance plugs for green corroded wire, and replace as needed.

• A dropped pack gets set aside for disposal, every time. I had one I'd dropped on concrete get back into rotation. It started making noises on the charger at a hotel at Nationals, and I got it outside just before it went up.

Next up: Pneumatics, Cannons, Regulators. Questions? Find me on the Unofficial IRCWCC Discord or email info@southjerseyshipyards.com.