In the first article of this series, I covered the cosmetic changes that I incorporated to make my Alpha Patrol Boat from ProBoat Models look like the Erebus from 'Apocalypse Now'. This time around, I'll talk about mechanical upgrades that I made to the model. These changes were intended to add a little more realism, make the model more dependable, and also make it easier to drive. As before, some of the techniques I tried were new to me and the efficacy of my efforts varied.
The model comes with most of what you need to make the forward gun turret articulate. There is a servo mount inside the hull below the turret. The turret itself has parts to attach it to a standard servo arm. The only thing missing is the actual servo.
I used a Spektrum S605 waterproof servo ($14). It bolted right into the existing mount and the included servo arm mated perfectly with the turret. The boat's manual indicates that you cannot add a servo to the turret if you are using the included 2-channel radio system. That's not entirely true. You can use the stock radio if you connect the turret servo in parallel with the steering servo using a common servo Y-cable. You just will not have independent control of the turret. It will move in response to your steering commends.
I didn't think that I would be coordinated enough to command the turret and drive at the same time. So I was planning to keep the stock radio and connect the turret to my steering channel. As I dug deeper into the project, however, it became clear that my other upgrades would demand a more capable radio. I swapped out the stock radio for a 4-channel Spektrum DX4C pistol-grip controller and SRS4210 receiver. I still slaved the turret to the steering. The DX4C's channel mixing menus allowed me to skip the Y-cable and accomplish the same goal. Less wire is always better.