• 3.5" OTW Dive Module - DUAL SHAFT

    NEW 3.5 inch diameter module with single output drive shaft.


    The standard version comprises of three tubes, measuring 8-10-8 inches, giving an overall tube length (including end caps and bulkheads) of about 27 inches.

    The FRONT section houses the + and -  input terminals, reversible water pump, solenoid valve and the pump control unit. The latter three mounted on a CNC`d tray. This front tube is attached to the middle BALLAST  TANK by three brass tie-bars.


    The 10 inch ballast tank has two baffles mounted on the central conduit which allows the power and servo cables to run from front to back.


    The THIRD and final tube, also connected by three tie-bars to the ballast tank, houses the propulsion  motors, speed control unit and, if required (at extra cost a digital self-levelling unit,) plus two push-rods for the rudder and the rear dive planes.

    The standard unit uses a sealed ballast tank. Venting of the tank to the remaining pressure vessel is possible with a simple 1/16" hole in the rear ballast bulkhead. This increases ballast capacity and reduces strain on the pump. 


    This unit does come with a forward push-rod, but a forward pushrod is available as an add-on option. All push-rods are stainless steel and come with clevises and waterproof bellows.


    Different length Ballast tanks are available by request.


    •    All our units run on 12 Volts and incorporate two fail-safes as standard.
    •    All wiring is connected with plugs for easy assembly and disassembly.
    •    All our dive systems come fully assembled and tested.

    NOTE: Product photo shows some optional equipment.

    • Details

      The module comes with the following items:

      • Two drive motors complete with motor mounts and waterproof shaft housings for the propeller shafts.
      • A speed controller rated up to 30 amps.
      • A BEC, which allows you to run the whole system AND the radio off a 12V battery.
      • Reversible water pump and hydraulic valve.
      • Electronic pump management system that is complete with two failsafe modes.
      • Three ballast tank probes.
      • Three stainless steel pushrods and clevises.
      • Three waterproof silicone rubber bellows for the control rods.
      • Two waterproof external battery connectors, one positive and one negative.
      • A set of baffles in the ballast tank.


      The electronic components are mounted on two easily removable trays. All internal connectors are of the Tamiya type. 90% of the components are produced in-house.

    • Shipping and Final Price

      These systems are sourced from the UK and due to the fluctuating USD/British Pound, the Nautilus Drydocks reserves the right to adjust final price depending on current exchange rates. 

      Shipping prices will likewise be adjusted at the time of final invoicing.

      For any questions, or for an accurate quote, please contact us and we will return your inquiry immediately.

    Ballast Tank length
    Add Self-leveler?


    The Nautilus Drydocks is the world's premier supplier of kits, parts, components and resources dedicated to the hobby of remote controlled submarines. 



    983 Tivoli Dr
    Naples, FL  34104 USA
    Phone: (239) 877-4280

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