Kayak motor

Here is an example of using drill longtail

 

I have used a 30 pound thrust trolling motor for the service you intend, and it has been entirely satisfactory cruising around in my 11 ft canoe, also 17 ft Grumman Square stern canoe with two passengers. These cost little, and are pre-engineered, 5 forward speeds, 5 reverse speeds, and a 12 VDC autompbile battery will let you cruise for several hours.

The motor you referenced has a maximum of 3200 Watts? That is far beyond what you need, and probably would turn far too fast, and need reduction gearing. Toothed belts are silent, but then you need to engineer, and build the reduction system. I agree with Gonzo, just get a small trolling motor, unless of course, you enjoy building unusual technical challenges. Hell, some even build sidewheel paddle boats powered by steam engines.

 

I originally had an e outboard, but I found that with power the thrust from the propeller forced the outboard to try to turn on its bracket, whereas with the longtail the thrust was directly in line with the vessel's direction and thus easier to control. The shaft was joined to the aluminium tube by a bungy strap which allowed movement of the motor for steering.

 

Lachie, what is the diameter and pitch on the propeller in your picture above? Did you experiment to find the best aluminum prop? From what I have read, the cordless drill will tend to overheat if propulsion is used continuously, unless the RPM is kept fairly low. Any idea what RPM you have been using?

 

I always had 2 brushless drills at $30 each so one could cool down both connected to 4ah batteries, they were normally run at about half revs which worked OK, not too hot. I still use the drills today. I checked today and the diameter is 7 in and they are made by KKK in Thailand, they are on the internet. Made of aluminium and will cost you around $3.00 US, look them up. It could be a good business for someone, the sort of get me home motor you keep on board, in case. I used threaded rod with agricultural 3/4 riser pipe and bolts and washers to keep it in place, same with prop and loctite it, cheap, simple and effective, cheers

 

Thanks for the info Lachie! Did you use any bearings on the two ends of the exterior pipe? Seems like threaded rod would cut/abrade the surfaces as it spins inside of the outer tube.

For those that don't want to build their own, you can get something similar on Amazon and other places,

https://www.amazon.com/Drill-Paddle-Outdoors-Pontoons-Watercraft/dp/B00KSWZZAA

The Amazon written reviews will give everyone an idea of the pros and cons of the setup.

Hope this helps.

 

No just 2 washers and nuts ( with loctite), the same with the prop. Contrary to what you would expect, apart from a rattle no problems. If using mild steel, the threaded rod would start to wear away after a while where it locked into the drill, I think because it on occasions was not tight enough.

 

Check out the brushless ROV motor’s being made by companies like BlueRobotics. Their T200 could easily be mounted at the end of a shaft supported through a gimbal mount for full steering and trim capability.

They sell I nice little external speed controller for it, even sell them with the controller built in.

Efficient powerful little lightweight motors with spare parts readily available.