Remote Stow Trolling Motor for 2 Person Kayak

My kayak is a 17 foot sit inside type (2 person Folbot Super) and its design precludes reaching the stern where a trolling motor could be mounted. Two problems arise, first the standard trolling motor is a transom mount, and the pointy stern has no transom to mount to, and second, I couldn't reach the stern to raise, lower, and stow even if the motor could be mounted there. Kayaks are often used in shallow water, so the ability to raise and stow a motor is needed to prevent getting stuck in the shallows. . A Minn Kota Ulterra is the only self stowing trolling motor, and it sells for $4,000. A cheaper version was needed, so I bought a Minn Kota Endura for $100 and did DIY on it to make a cheaper remote stowable version.

I made 3D printed trolling motor parts that replace all the stock transom mount parts that came with the motor. These parts fit the motor to the stern and fit where the rudder would go.Two small electric motors were added, one to tilt the motor, and one for electronic steering. My first design had a lift motor, but I found it easier to just pull the motor up via a cord. The tilt motor required a lot of thought; the motor needed just the right gear ratio to raise the heavy motor to the horizontal position. I 3D printed the gears in Nylon, the larger gear had to fit over the motor mount and be concentric with the mounting bolt. The smaller tilt gear attached to the motor had to climb up the larger gear during the tilting process. It took quite a while to get just the right gear thickness, stiffness, and alignment. The steering motor drive gear, shaft, and feedback gear use Nylon gears, although PLA+ works as well. An Arduino controls the 2 motors via separate H Bridges. A handheld remote has a steering knob, 4 buttons for tilting and alignment, and a function select switch.

Because the trolling motor center of gravity about the motor shaft is toward the prop, when the motor is raised and tilted, the motor swings prop end down. This would present a problem when the motor is tilted back down, because then the motor faces backwards and the feedback pot aligns backward as well. A button on the handheld remote corrects the alignment via software.

Fusion360 files: 3D printed assembly

3D printer. I used an Creality Ender 3 v2 (around $200)

Fusion 360 3D design software from Autodesk. Free for students and hobbyists.

3/8" bolt and nut 4" long

4 ea, 3" diameter Automotive hose clamps.

3D filament. I used Black Nylon, though an early version used PLA with good results..

Flexible power cables for trolling motor. I bought super flexible wire, though you could use the stiff stock wire that comes with the motor.

Ribbed flexible plastic conduit 1/2" diameter for power cables for a neater look

Waterproof project box for the electronics on the trolling motor (Small Pelican case)

Greartisan DC 12V 11RPM Turbo Worm Geared Motor High Torque Turbine Worm Gear Box Reduction Motor 6mm Shaft JSX950-370 for tilt motor

Bringsmart 12v 40 rpm DC Worm Gear Motor 40kg.cm (amazon) for steer servo

Hall sensor, 3 pin, 49E (to detect motor position aligned - amazon)

Hall effect potentiometer angle sensor 360 degrees 0-5v output, 5v supply voltage (amazon or aliexpress, for steer servo)

Arduino Pro mini (amazon)

10k center detent potentiometer for steering (amazon)

knob, for steering potentiometer (amazon)

PCB mount pushbuttons (4 ea) (amazon)

assorted resistors for pushbuttons (amazon)

small slide switch (amazon)

3D printed case for handheld controller

wire, 20 gauge, 50 feet

wire, 7 conductor 8 feet

servo extension cable 12 feet

This instructable is just for reference about how I made the trolling motor stowable. Unfortunately, Fusion360 does not allow sharing the design files unless you have a paid subscription. Hopefully there will be a way to do that in the future, or I could share the Cura print files, but that would depend on your printer and print filament settings.

The key to this project was recognizing that the stock motor's mounting system and manual tilt would not work in this application. I tried fitting an adapter to the stock transom mount, but it was too bulky and wobbly. After I designed a new motor mount (motor shaft support tube and mount adapter) that fit directly to the stern of the kayak (where the rudder used to go) I could manually raise and steer the motor. I even had a pull cable to raise the motor. But that wasn't ideal, as I couldn't entirely tilt the motor out of the water. Thus, I decided to make this design with electric motors for raising, tilting, and steering.

The system works well.