New electric foilboard

[dirkdiggler]

I know most forum users ran off to the efoil.builders website, but for the truly faithful ES members, here's my repost from there. ES is where my gratitude belongs.

I wanted to do a write up for myself and posterity on my own foil adventure. Most of it will be me rambling on about other electric projects, but I will get to the foil part soon enough. If you don't care just scroll down for the pictures. I know I didn't get here first and their were many people with greater skills than I have that helped me and everyone else get to this point,

It'll all started back in 2010. I saw this video on Youtube:


I think his name was Humboldtstoner420 at the time. I had a super heavy lead acid eskate at the time that put out 600w. Heavy as crap, with huge wheels. This mountainboard is what I needed. Looked way fast and could go offroad. He had a build writeup on the old Hobbyking forum. During this time I was getting back into RC cars and after struggling for days trying to get a Nitro to work, the local hobby shop recommended I go electric with Lipo batteries. I tried to copy Humboldt stoners build and ordered all the parts. I had a few mountain boards as I was into kiting with them out at the salt flats. The area I rode got shut down, so I needed to find a use for them. Humboldt moved over to Endless Sphere to post and I followed him over there. The build took some time with my lack of skills, but finally got some metal plates welded up and everything fitted. The chains kept popping off. I decided I needed some aluminum mounts and my brother in law was able to get some made at the machine shop he worked at. I think this was about a year later. Here's that vid:

I realized how this worked so well, I mine as well get it put on a longboard to ride the streets. My trails weren't the best for the mountainboard and I had a few too many crashes. Amazingly Boosted boards announced a kick starter around this time. There $2000 board didn't look much different than what I had planned to do. Parts from hobbyking could make this thing similar for around $500 and there was a six months or so lead time to get the Boosted board. Some guys on Endless were already starting and a few guys, Pyschotiller, Papo, beetbocks and Matthias were already riding their boards. I finally got my board going in 2012 with the help of some welders and even did a write up on Endless about it. User DIY skateboards was starting to charge for the same how to and was starting to sell kits, so that upset me enough to do a whole writeup to make it easier for anyone to make one.


Around this time, a friend of mine wanted to go mountain biking. I went with him and he killed me! I decided right there, I would do the same to him next time. I was going to buy a hub motor kit and whip him up the hill. I had the batteries and such, just needed the motor. I bought a $200 kit off ebay and proceeded to do an ebike. Endless Sphere was mainly focused on bikes at the time, so tons of helpful info from there. I'd also finally looked into the water part of the forum, but I'll get to that later... I ended up really enjoying the bike. We have tons of local trails that are perfect and I loved being able to stop when I wanted and not crashing due to hitting a pebble. My street roads had just been paved with gravel, and I couldn't ride the electric skateboard much. The issue I always had with the ebikes was the size of the controller. Why did they have to be so big? They were meant to be put on a bike! The bafang 750w middrive came out and I had to get this, the controller was in the motor. Awesome kit. A buddy had just gotten the $7000 Haibike which is cool, but so expensive. This bike had so much more power and was so much cheaper. Like every builder, I still wanted to go faster and have more power for climbs. I decided to go with the Cyclone 3kw and now the Surron.

During all this, I continued to be interested in doing a surfboard. Matthias had started a build, but with limited info, it was hard to piece things on what he had done. Here's his vid from 2012:

It has been a dream since I was a kid to learn to surf, living in Utah with no surf made that a challenge, but I started snowboarding back when that came out, wakeboarding when that came out, kiteboarding when you didn't know if you'd actually die launching your kite and then wakesurfing. I almost bought the gas powered surboard version from the 80's and there was a Popular Mechanics article about the self driving boat that would pull you as a water skier that seemed fun. Both products looked like junk and I knew that an electric surfboard would be lighter weight and easier to maintain. I think Jetsurf was starting to show up around this time too, but still too expensive and I knew I wouldn't be able to keep the motor working. Even back then there was discussion about an efoil. To prove the point, along with the history, here are a few screenshots from ES going back to 2009:
viewtopic.php?f=39&t=41960&hilit=surf&start=25#p674857
      
Here's a quote from my post back then to Matthias:
(viewtopic.php?f=39&t=41960&hili ... 25#p674857)

(posting.php?mode=quote&f=39&p=674857)

(viewtopic.php?p=674857#p674857) by **[dirkdiggler](memberlist.php?mode=viewprofile&u=29922)** » Dec 10, 2012 7:25 pm

What is the latest on this project? I watched the videos and it looked like it would work well. I am curious what battery and motor setup you are using. After finding out the price and performance of the gas powered surf board, I want to build one for myself.
Thanks,
Digg

I made a few attempts at this over the years. I bought an old jet ski for the pump, bought a Kayak to try it out, bought about 4 different props that never seemed to work. Motor would always go out of sync or I'd have issues like the prop falling off. Here's on of the reasons why I had so many issues, didn't realize it at the time:

There were others on the forum, Bazaki, Ratking and Jezza that were interested in doing the electric surfboard - apologize if anyone else is here that I didn't mention. Not much luck from anyone. After hundreds of hours in the garage and time driving back and forth from the lake, I realized I would have to be patient on this project. In the meantime I had almost given in and gotten the Onean board that was coming out. Finally something reasonably priced for what I was paying for. I actually had planned to fly to Spain and test it, but things never worked out.
Thankfully I saw Lift and their working board in late 2016. Pacificmeister, Hiorth and a few others finally got working efoil boards in the summer of 2017. I purchased a slingshotfoil and 3d printer (which I should have done long ago!) that summer 2017 and decided to learn to ride so I could eventually build one myself.

As the summer of 2017 was coming to an end and at least being able to stand on the foil, I finally got a chance to try out my first setup - a c80100 motor with a 3d printed prop and a 48v Hobbyking ESC that I'd used for an emoto. Exciting times. I figured I'd be cruising around the lake for the first time since I wanted this six years ago. After hooking it all up and getting in the cold water, I hit the throttle. I hear the dreaded sync squeal, but I did go a few feet with some power. I try it again with some kicking and then smell smoke. Shiii....!! I open the Tuperware waterproof box I was using and see the ESC burning. Water had gotten into the box. So what was the problem, water or the ESC? I knew that the issue people were having was the same common thread from ebikers that were using RC components - no current limiting coming from the ESC. I thought that would be the best route to go now, even though I had purchased all the components to do a similar build to Hiorth's. least now I knew that it does work to hydrofoil and what kind of power was needed. I had two options that I had in my garage - the c80100 that I'd used for my kids emotobike and another Boma motor that was similar, but an inrunner. I printed out 3d parts to connect both to the mast and I had two ESC's set up - The ebike controller that was 48v and 80a and the SeaKing.

[dirkdiggler]

I try again with a number of different props and an old 6s boat ESC. The props fly off or break and nothing seems to work. Meanwhile, the weather gets cold and I don't have another setup to try before I am done for the season. I buy as Christmas presents to myself the missing gearbox for the SSS motor and the Seaking ESC.
Over the winter I read up on all the latest as the forum moves over to efoil.builders from Endless Sphere. Still seemed too complicated to run all that stuff with talk of needle bearings, seals, extra shafts and couplers. I know from experience how much more powerful the big motors are. Everything works in my head and on paper. I decided to try out both options from last summer, the c80100 and the Boma motor. I printed a prop for the c80100 motor that enclosed the whole motor with the prop designed on the outside of the can. As the can spun the prop would turn and there wouldn't be a need for anything extra. No waterproofing or anything, just had the cover screwed into the motor. For the Boma 1500w motor, I just fastened a Solas prop on the back with a set screw. This time I try both setups in my backyard pond. I'm not driving to the lake to find out the prop is unscrewing, the set screw is coming loose or the prop blows up and flys off.

After finally getting back to the lake, which is an hour drive or so to get there and fifteen minutes of setup - I'd usually end up with myself getting wet and disappointed. I decide the c80100 looks to be the most probable for getting me going. Also the risk of hitting the open prop is less, which has always been one of my biggest concerns. I get in the water with everything plugged up. The 48v ebike controller, wired remote, pelican case on the front of the board - a Slingshot Simulator 5'2" board which I'd borrowed to give me more float. The case goes under water when I lay prone on the board. As I know that isn't good, I put weight on the back, cautious of the prop, hit the throttle and the board goes. It goes, but not quick enough yet for me to get up on foil. I keep leaning forward on the board thinking that will help. No go. Later I realize what I'd done wrong there... I keep trying for the next half hour or so. Never enough to get up even though in my head things should work, especially at this speed. I keep checking the esc temp and batteries. I'm using the Multistar at 20ah on 12s. Then it happens, the motor is spinning and I'm slowing down. I swim back in with shame. As I lift the board out of the water, the problem is there, no more prop fins. All of them were gone. A guy watching comes over and talks to me about my front wing. He just got a foil and got the huge sup front wing - the infinity from Slingshot - could that be the problem? I figure that's my next purchase. A fool and his cash are soon parted! Too dark to try again, I drive home thinking how I should be leaning back to get on the board to get on foil not forward. Complete opposite of what I did. Would it have worked if I had done that? Should I give up on the motor and move on or was it enough to get up? Was the 3d print off and that is why it broke? My 3d fusion skills are still lacking to just add thickness to the prop, normally a quick job, but for me a few hours of frustration.
    
Determined to just get going as the summer is half over, I bag the idea to reprint the cover and just go with the Solas prop. That thing at least won't blow up on me.
Meanwhile a friend of mine, knowing my trials with building an efoil - has been talking to some people about getting a board. He runs into the same problems as most of us here - there isn't anything available for a decent price. We talk about the fact the whole setup shouldn't be more than a few thousand. I mention, I've easily already spent that over the last five years trying to save that money and have nothing to show for it! I should have just gotten the jetsurf and enjoyed myself all these years. I know that most of the fun has been in the garage, but I won't admit that. I think that is why the ebikers are perpetually building new bikes. It is a way to get your mind off all the other problems in your life. I did the same, the minute I got things working right on one of my projects, I'd move on to the next one before I really spent anytime on the finished product. Talking again with him, I decide that even if I do get this efoil working, I'm going to have to find someone to build a board, build a better enclosure, get a waterproof remote, and finalize a carbon fiber foil mast that will have motor mounts. I do have to face it. I don't have the skills for this project. I can barely 3d print, barely model more than a box. I can barely put together a foil. I don't know how to lay carbon fiber.
I don't know how to chop a surfboard in half and fiberglass the ends. I don't have a lathe and can't mill parts out of aluminum. I don't really know the difference between a ball bearing and a needle bearing. I don't even know what foil shape is best. Heck I can barely ride my foil behind the boat.
I definitely can't pump on the second wave. Who am I kidding on this? He says he knows some people that know some people... The same guy needs the Slingshot board back to do some kite foiling and I'm out of luck. My foil board is stuck in my boat a few hours away, and I'm not getting down there for another month or so. The lake where my family goes is almost empty and has some algae bloom making it unsafe to swim. No more wakeboarding, wakesurfing, or wakefoiling this summer. My kite bladders are even all blown out. Not that we have any wind this time of year either. Ouch! (Still have some fun ebikes though!)

A month or so later, and a few thousand emails, my buddy's contacts send us the board. Just in time for the weather to change for the worse. The season pass is already bought, a new snowboard ready to be waxed. It's the real deal though this efoil, a carbon fiber foil similar to the Slingshot Infinity I'd ordered after seeing it the first time, which still is on backorder. A giant 40Ah battery. A board with a waterproof deck lid, enough space for the controller and battery. The motor, close in size to the Boma but waterproofed with a protective duct and a four blade prop. It had a battery gauge I could see built into the board. None of it 3d printed, none of it that looks like it was made in my garage. My first attempt is heavenly, almost surreal. I've ridden the jetsurf and it was kind of a nightmare. A pain to water start and harsh on my legs and feet. This was different. No chop, felt like riding powder. I was riding on electric power with nothing but a hint of noise from the motor and the rustling of the wake I was making. I rode solid for an hour. My legs sore and stiff from trying to keep up on foil. I'd fallen a bunch and it had taken some getting used to, but it was great. As I am taking the board apart on the beach the sailing crew that was out there kept coming in to take out their boats. Thinking I was hot stuff on the beach, e-foiling, first in the state and all that hard work and effort. How cool must that have looked? A couple of them mention they never saw me get up on foil, doesn't it work they ask. There goes my ego! I want to yell, you try this thing. Its not easy, and plus I was foiling, just would rather crash from a foot out of the water than 3.
But, after all the years, it was sweet. I've been out about ten times in the past few weeks, even with temps getting cold. I remember Hiorth in a Santa suit and tell myself to toughen up. We have had some issues with the board. A remote that wasn't exactly waterproof - which who knew. A foil, like Lift that had too much flex and cracked. All in all, everything seems to work. It should, it is electric. No mixing gas, no clogged carb, no bad plugs. As long as the controller doesn't catch fire, or the battery has issues,then we'll be in good shape. The thing should last for years. I'm done with projects for a while. I do feel like I've cheated, especially seeing all the effort and hard work that has gone into everyone's builds. Finally it's time to ride!
Now for some pics.
              ![20180918_162643|690x388]


https://www.youtube.com/watch?v=s4QURUBh3lA
I will update links when I can.