The outing the other day had me returning to my experiment for countering prop walk. A stern thruster would cost about 3k USD before install. So probably a 7k CDN bill. I do not need it this bad.
However; the idea is to mount an electric trolling motor to the swim grid and control it from the wheel house. (about $400 all in). This is not to be a proper stern ‘thruster’ – just a bit of help to counter the prop walk as I back out of the boat house and out of the marina (where I can find room to spin the boat).
I purchased a Newport trolling motor a few months ago with this in mind. The blue tooth version (remote control) was tempting but at a 30′ max range this seemed too ‘iffy’. So I opted for a standard unit. Pulled it out and took it apart last night.
Expected the control unit to be centered around some epoxied-in electronics. I was particularly keen to understand how it reverses the motor. Turns out it is some pretty slick (read; simple), mostly mechanical, control. The reverse/forward bit happens when a pair of contacts slide to a new position. Fully mechanical really. The speed is handled by two dedicated wires (yellow and white) that run into the motor housing (which I did not take apart). The adjustment is made by sliding their contact along a metal plate. Again; essentially mechanical.
I added a switch and a solenoid to experiment with it because at this point I thought I would be running some thin wire to the back to trigger one or two solenoids to control the motor.
This mechanical business was not going to work for me as I need to be able to adjust remotely – from about 35′ away. So I removed the entire control.
So the useful bit of the trolling motor is the motor and the pipe. The motor can be made to work by simply using the +/- wires and ignoring the white/yellow. The direction of spin can be done by a relay/solenoid made for this purpose – such as one used for controlling a winch or an actual thruster. I pursued the ones for a winch as they are cheap (< $100) and the ones for thrusters are expensive (> $500). I was also looking for at least 100amp capacity as the motor is 50amp.
Went online to find a solution. I found that I could get the solenoid with a wireless control. Importantly; the wireless was via radio frequency (FM I think) and not whatever Blue Tooth uses. So the range is much greater. So I ordered a kit. It will be interesting to see if there is any interference with the wireless by other devices in the area. I know that Warn makes a remote for their winches and they specifically state that the remote and the receiver are paired to only work with each other – nobody else stated this.
This project will resume in a week or two as I am now waiting for the kit. Decided to spend the rest of the evening sorting out 12v supplies so that I have a more robust 12v kit on the boat.
