Electric v gas outboard: R & D for self-rescue.

[@mjf1036]

I love that you are open minded to shift the project as your interest change. Thanks for the reminder to not be overly rigid it our pursuits. Life is an adventure and we are never in control as much as we tell ourselves.

[@garygrissom1031]

Cant lie your bicycle raps and bike builds brought me to your channel but i love your content and adventures Paul i appreciate you sharing . life is way to short not to enjoy yourself so do what makes you happy. Thanks again Paul

[@fossilfool]

Thanks a lot Gary. There aren’t too many people who’ve stuck with me this long after going from rapping to sailing and beyond. You’re always one of the first to drop a comment. I appreciate your interest and support. Did we meet in the world at Rock The Bike event or only through KZbin?

[@garygrissom1031]

@@fossilfool just youtube im in Washington but you have me as subscriber love the content keep doing what makes you happy

[@john3Lee]

If I was converting to boat electric propulsion I would convert a small outboard motor.. Just replace the petrol motor, and use all the shaft and gearsbox components... Good luck, I enjoy all your projects... Cheers

[@fossilfool]

I’ve seen that approach on Pauli Juppi’s channel. I want to make a lighter outboard using a carbon over cedar shaft, and I’ve made the structure for that already ( next video) . What I like about the approach you’re describing is low drag in the water. What I don’t like is the inefficiency of a gear box and having to use a heavy gas outboard structure. Thx for checking out my progress so far!

[@davidyeager8869]

Interesting build, I think maybe overkill for your craft, 1kw should be plenty to get you home in most conditions with the right prop pitch. I used a 1kw torqueedo on my 11metre long ,1500kg sailboat and it would push it into a 12knot breeze at 4knots. Unfortunately it was impossible to buy parts from torqueedo, I had some electronic glitches and just got the “return to your dealer” brush off. Much better to build up what you need from generic modules as you’re doing. Good luck, you’re learning fast!

[@fossilfool]

Thx David. The power difference between hull speed and planing is indeed striking. I have been impressed at the speed I can go for only 500-1000W. I don't know how to find props for the motor spline that Maytech sells so I have been stuck with their prop. I do find it challenging to go fast on this boat, so I'll probably continue trying to make something work in the 10-12KW range.

[@hurdurdur7rl696]

the exclusivity of parts / battery of the torqueedo is scaring me off as well. i do not mind a lithium battery for the price alone, but i do mind on being vendor locked for all the parts. this is not fun. and as i live far from places that could have them on the shelf i do not wish to wait for weeks without sailing to get them. we need standardized cables and plugs for such things as the first step

[@iamyourantonberteaux3296]

Some thoughts: I put a 4kw Torqeedo on a Prindle 19 catamaran and was able to go about 12knots (It's been a while, and I didn't write anything down, so consider these numbers nominal) at 4kw with one person at 150lbs, in a 300lb boat, and maybe another 350lbs of stuff. I could do 6.5 knots at about 800 watts, which was the amount of solar I had on the shade cover, so in theory I oculd do that as long as the sun shined. Note more than half the speed at less than 1/4 the watts. That is a lesson about boats and powering them Consider a Yuloh. I have no direct experience with one yet, but it is said that they are more efficient and much easier to use than just sculling. It is a special kind of sculling oar that is tied to the boat so you just move it back and forth, you don't have to use muscle to push the water. The bluntness of the motor is a problem, if it were tapered for a distance after the blunt back end of it, the suction of the propellor would keep the water in smooth flow from the wider section to the back, and would allow the smaller prop to work much better. One of the ways the torqeedo motors get efficiency is by using large props, so if you wanted to be way more efficient, you'd go slow and use a big prop, in fact I have a torqeedo prop that I plan to experiment with, possibly even with that exact motor you are using. If you want to borrow it, I could send it your way. I have sent you a friend request on FB. I think you're probably smart enough to not need the advice, but you can buy those little props for cheap, and just machine them down to get the spline, and stick it into another prop that you want, or use that spline to make an adaptor for something more universal, like a sacrificial drive pin so it doesn't break stuff when you hit something with the proop. Torqeedo uses an inline planetary gear box to make the motor rpm lower for the big prop, you probably won't get a good result trying to trun a large prop at 1200rpm with that motor, but then again you might be fine as long as you don't want mroe watts. Might work very efficiently at 3kw, who knows. Awesome project!

[@fossilfool]

Those are useful numbers, thx Anton

[@EdwardSeatonSailings]

This was a fantastically informative video. Thank you for taking an enormous amount of time to create it! I am living on a small sailboat in Bodega Bay and I have wanted to move to an electric system since I moved onboard. I have an idea of a plan, and I think that by sharing it with you, we both might benefit? Basically, I'd use 2 electric outboards, not 1. Of course I'm trying to push a 32' sailboat and I'm only trying push it 5-6 kts. I was thinking that I'd try these 86lb thrust electric trolling motors that you can buy on amazon for $300. I will have to design a couple of super sturdy brackets on the back of the boat to lower the motors into the water when needed, which ideally, if you're dealing with a sailboat, to get to and from your mooring or trailer, to the windy bits. Motor sailing is also a thing. A little bit of power goes a long way to clean up sloppy tacks. The main reason I think you should use 2 motors and not 1 is that one could theoretically achieve an autonomous steering system with few moving parts, meaning you wouldn't have to swivel the motor to steer, simple change the thrust of the motors. What would be super-duper cool is if you could have the craft hold a particular heading. Curious where you are with this project in general. Maybe we could bump heads

[@fossilfool]

Hi Edward, thx for reaching out. I bought into a keelboat recently and am excited by this opportunity. But for our keelboat we are going to leave the Atomic Four gas engine in place because bringing a bunch of new lithium into the world to replace very small sips of gasoline isn't sustainable. There are a lot of good project videos on electrifying boats in your size range. I wouldn't experiment, I would copy! I think I am paying an efficiency cost for going with the motor and prop I have chosen. This is based on my conversation at the Wooden Boat Forum with similar sized boats. forum.woodenboat.com/showthread.php?251743-Building-a-scaled-up-Lillistone-First-Mate-in-G10-for-Bike-Sailing/page7&highlight=bike+sailing

[@davidyeager8869]

Your boat Is not designed to plane, it’s a displacement hull that can be forced to plane with enough power, but will never be efficient at speeds above hull speed. The difference between 5knots and 10knots isn’t worth 12 times the power consumption! Also if it’s rough you won’t be able to maintain planing speed anyway, you won’t be able to retain control and will probably damage the hull. Stick to hull speed and your pack will give you a huge range. Do some research on props, the one you have is designed for high speed, it’s too coarse in pitch and too small in diameter, I’m guessing something like 12inch diameter and 6inch pitch running at 1000rpm would be in the ballpark for your boat at hull speed. Model airplane props are very efficient, inexpensive, and available in a huge range of sizes and pitches, and are used in a lot of experimental boats. Dont give up! You’re on the right track!

[@vintagesimpilot2623]

Interesting. I'm about to install an off-the-shelf electric trolling motor on our Capri 16 (keelboat). The intent is to just use it to slowly putt-putt back into the harbor when the wind dies and also maneuvering around the dock. In terms of battery voltage (AGM), at what point will I damage the battery if it goes too low? Also, I guess I'll probably need to fuse the positive side of the battery cable as well as put a simple voltage meter in line. Or like you did, increase the cable to 6 awg. All I have is a VOM and that would be to awkward to take along onboard. Do you have any recommendations on such in-line products or solutions? Really trying to avoid a gas outboard. I've used this motor on our 23 foot Santana once but for just a very short distance into a bad headwind. Wasn't nearly enough ooomph for a 2500 pound boat. Presently lake sailors - miss the Bay! Thanks Paul.

[@fossilfool]

I would check out solar charge controllers or Voltage Controlled Switches that might be rated high enough to handle the putt putt wattage and then follow their guidance for cutoff voltage, probably 11V for a normal 12V battery. I suggest the Cycle Analyst high current, which is the computer shown in the vid, for monitoring purposes, and there's nothing wrong with having a voltmeter on board. Putt putt over flat water is many times smaller wattage than what you'd need to fight a headwind. So it might work out well, but of course you'll be the judge of whether it's underspeced. Thanks for watching.

[@johnmorgenthaler3611]

Have you thought about doing something like an Asian style long tail electric drive? It could be low tech and the electric motor could Be out of the water and you could fab a lot of it out of carbon fiber and it’s very low drag.

[@fossilfool]

This is the first I’ve thought of it. Will be testing a transom mount approach next. Thx for the idea:)

[@torbenbohansen7643]

For your information, CO2 is not a pollutant (it's the molecule of life and a blessing from God) and does not course global warming (the Sun does). As for motors, get the Suzuki DF2.5 and use it at low throttle.

[@fossilfool]

You're right that CO2 is natural and serves an essential function for life on earth. But my understanding is that burning up all the old carbon from previous geological eras is now upsetting the balances of gasses in the atmosphere, causing the sunshine to warm up the planet more than is healthy.

[@fossilfool]

An important question is whether lithium powered vehicles like electric cars are helping or if they just make people feel good while maintaining a high-carbon lifestyle. My sense is that lithium can be charged with renewables in a smart way (like using wind when the wind is blowing or sun when the sun is shining) and that it can be an important tool in our box for getting out of climate catastrophe, but that we also need to reduce our total use of energy.

[@fossilfool]

What you said about low throttle is really important. Going slow in a boat uses so much less energy than going fast.

[@hurdurdur7rl696]

I love the experiment stuff you do on regular basis, but please don't mess with electricity like this. A 12 gauge has no chance to stay intact in the scenario you described. My 20 foot sailboat has a 600W / 50amp motor attached to it and i run gauge 10 wires for it. Don't mess around. Do your math first. Ampers need a lot of copper.

[@fossilfool]

Hindsight is 20/20. Wish I'd used more copper indeed. I had always been fine with 12AWG for electric bike projects but this is 5X the power !

[@hurdurdur7rl696]

@@fossilfool also extra power has diminishing returns as you go up. you can do the tests but probably if you go from 2kw to 4kw your energy consumptions goes 2x while the speed will increase 1.2x. if you are sold on the idea of electric - i can not imagine a situation where you should be on water with this skiff and need more than 3kw at all, even on the ocean. and if i was really honest, on the ocean i would rather trust the 2.3hp gasoline engine instead (the simplest one, air cooled, without an impeller). they are a bit loud but bulletproof and foolproof. if the CO2 footprint annoys you, plant a few trees every boating season :)

[@hurdurdur7rl696]

As the waters were calm today (little wind) - i did a test on the local lake on my 20 footer. the "50 lbs" minn kota c2 pushed me at 1.5 knots on ~10 amps, 2 knots on 20 amps ("4th" gear) and 3 knots on 40-50 amps (the final gear that it has). for the reference the boat is a fabola campus 600. quite a bit heavier than yours i believe. i have also pushed it in the past with a 4hp yamaha over 5 knots. in heavy weather that is sufficient for the boat. And if you think of rowing as a reference - with the oars you move the boat pretty solidly, but i am pretty convinced you can not even output 250W for a sustained amount of time, that would be 20 amps on 12v :)

[@fossilfool]

@@hurdurdur7rl696 Good data. I know about the declining returns of dumping KW into my electric outboard, but I also just want to plane. It seems like I can go close to hull speed for 2kW but if I want to plane, I'll need 8-12kW. The carbon footprint of the lithium battery may be higher than the gas I'd burn, so that's an important perspective. Thx for all your comments.

[@lloydsumpter7735]

If you're going to design your own electric system, PLEASE learn a little about electricity. A 6 hp motor is about 4 kw. That's about 80 A at 50V, so you need wire that will carry 80A. You didn't do these calculations before you built the motor system?

[@fossilfool]

I didn’t do the calculations before testing and regret it. Now I’ve upped the battery wire gauge to 6 AWG and it’s no longer overheating. Interestingly my motor is using 12KW at full throttle, not 4KW. It would be amazing if I get 3x the power as the borrowed 6hp gas outboard. Maybe I could hit 15 mph or more!

[@fossilfool]

Sometimes the calculations lead to over-specing the wire. For example, on my first test, the battery's BMSs limited me to about 70% throttle, which works out to 3-4KW or 40A on the section of wire that later failed. At this power level, the 12AWG wire was fine. It was only when I added more battery and went to full throttle, equating to 150A on the section of wire that failed, that the 12AWG wire melted down. And then it lasted 12-15 seconds before melting the insulation. In other words the 12AWG actually performed way better than the calculations would have predicted. I'm not advocating for underspecing but there is a place for integrating real world experience. My business Rock The Bike just got a 30KW solar install on our roof, and I was surprised when the crew showed me that the power was flowing through 8AWG wire. The crew pointed to the size of the individual copper strands within the 8AWG wire and said that some 8AWG wire can flow more amps than others.