Hey got a few technical questions I’ve always wondered but needed a lil depth on? This is for a project I have NOT started and may not for some time… depending on how this thread goes…
I’m looking to build an amphibious electric pontoon boat, wait hear me out, what Im thinking/wondering is if I aquire a used(or from scratch?) Pontoon boat is it possible to notch or section the pontoons in such a way that I can “store” the electric components IN the pontoons? (Properly sealed of course.) Meaning 2 battery banks tied to 2 motors, all housed inside the pontoons! Now whether those motors are prop driven or jetski “jets” is up to discousion… Now depending if all this works, and doesnt overcome its boyancee… Id like to have this contraption be “road worthy” aka if possible a pair of free rolling motorcycle wheels coming out of the bottem of the pontoons (shocks included) with a single wheel stearing on one end? This is all conceptial mind you!
Now time for the realing back to earth (from my head in the clouds!) How possible is most of this? The anphibiousness is obviously optional if at all possible… can a pontoon be used in such a manner and still allow the boat to float? (Stocks size need not be an hinderence!) Obvious battery compartment would be sealed off from pontoon, and liquid foam? Could be inserted into pontoon cavity to retain boyancy! Thoughts? opinion? Slap in the face? This is the result of a youth of watching shows like Junkyard wars and Red Green Teaching me you can make ANYTHING float! How long afloat was the variable!
Found an image of a pontoon boat patent done bout ten years ago, and this interests me for the amphibious mode, havine the wheels off center may not effect its in water ability. Dont know… interesting thing to throw in the design.
The major issue is weight and how much buoyancy you’ll be giving up by mounting the wheels and propulsion system inside the pontoons. I would expect the electric components (batteries/motors) to add many hundreds of pounds to the boat’s weight, thus reducing its carrying capacity severely. A typical 18 foot pontoon boat has a capacity of about 1400 pounds. 6 group 31 batteries will weigh 480 pounds and two 5-10 hp motors will weigh another hundred or two. That doesn’t leave much room for cargo in your weight capacity when you figure the normal 20 HP gas outboard and 6 gallon gas tank weighs only about 300 pounds.
If I were you I’d consider getting a 3rd pontoon to add to the buoyancy and put all your water drive and battery systems inside that center pontoon, eliminating (or adding onto) the engine mounting assembly currently in this spot at the stern. Adding a 3rd pontoon will allow the boat to keep its carrying capacity as well as adding to the stability and keeping the integrity of the existing sealed pontoons. You could then use a blown outboard engine as the basis for an electric drive and keep all the steering and engine tilt-up components. It’s much easier to swap propellers to get the appropriate pitch for your motor than it is to find custom impellers for a water-jet. And it’ll be lighter too. A GE SX controller or an AC controller (depending on motor choice) will give you a wider range of motor speeds to work with. It shouldn’t’ be hard to switch between water and land propulsion systems with those controllers either - just switch 3 or 4 wires between drive motors.
As for amphibious capability - you’re on your own there. I’d avoid putting any new holes into the main pontoons that would reduce their carrying capacity and go with outrigger wheels on the inside edges of the outer pontoons that you can lower to move it on land. Might not be as stable as recessed wheels, but you can’t expect a boat to make a good car anyway. It’s too wide and ungainly.
Thank you, that was VERY helpful, hadnt considered a 3rd pontoon, but it does make sense. Also with a third pontoon as the power source and battery storage, I could use a stock pontoon boat to begin with and scratch build the 3rd pontoon! Maybe out of metal barrels or something… hmm barrels would allow me to section off the individual parts into zones (battery banks 1& 2, and a “motor” barrel! Only having the needed wirering coming out of sealed factory holes… and the workings, if properly installed, could be easily removable if the need arose. In the end if properly designed this could end up being a third party alternative to a gas motor, maybe paired with a solar panel canopy to charge batteries… not a lot of sun obstructions in the middle of the water!