Florida Foil Assist DIY Build

[damandan]

I would like to thank everyone on this forum for all of the posts. I would have never attempted to build a foil assist if it wasn’t for this site. I decided after a successful first build I would post my build list and experiences in the hopes someone else gets inspired like I did.

I own a foil drive assist plus and love it. I wanted to take on a foil assist diy of my own but backed out a few times. My goal with this project is to get a more powerful assist than the foil drive assist so that I can foil on smaller wings. I’m 185lbs and I need a 1400cm wing to foil comfortably. I’m riding waves but when I’m not I like to stay on foil to ride back out. I can foil on my 1040cm wing but the throttle is close to 100% and I don’t get much time to fly 20-25mins.

Here is my build list

Motor - Flipsky 6384 waterproof - Flipsky Waterproof Brushless DC 6384 Motor 140KV 4400W for Surfing Boa – FLIPSKY

Flipsky foldable prop 4.8 - Flipsky 4.8 Inches 2-blade Folding Propeller | Motor Boat Propellers | – FLIPSKY

Remote - Flipsky V3 - Link
Box

ESC - Flycolor 160A Xcross HV3 - Link

BEC - Amazon.com: MZHOU DC 12V 24V 48V to 5V Step Down Converter Regulator 3A 15W Power Adapter Buck Converter Waterproof DC-DC Step Down Module : Electronics

Heat sink - Amazon.com: 4Pcs Aluminum Heat Sink Large Heatsink Chip Heat Diffusion Cooling Fin Heat Sink Black Heat Sink Cooling Black 50 x 12.7 x 100mm / 2 x 0.5 x 4in : Electronics

Waterproof Box - 11x7.5x5.5 - TICONN Waterproof Electrical Junction Box IP67 ABS Plastic Enclosure with Hinged Cover with Mounting Plate, Wall Brackets, Cable Glands (Clear, 11"x7.5"x5.5") - Amazon.com

8 gauge silicone wire 10 feet -

Mast Clamp. Bent a 1/4 piece of aluminum and a fiberglass puck on the back held together with bolts.
3d Printed a shell to go over it an cover it up.

Battery - currently using a foil drive 8s3p battery to test. On order have 2 6s3p batteries I am planning on running in series for 12s3p. 6s3p P42A Battery Pack | Transparent Series — MBoards

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Assembly steps. I cut a hole in the box the size of the ESC and used 3M 5200 to attach the heat sink to the outside of the box. The heat sink is larger than the hold cut by roughly 1/2". Then attached the ESC to the heat sink using thermal glue.

The box has a raised floor, I cut some away to make a strap to hold the battery
Also 3d printed a partition to split the battery side from the ESC and wiring side.

3d printed a mast cable guide to make a slimmer profile in the water. 8 guage wire was too thick and causing issues with air travelling down to the prop, so I split the 3 wires out and placed them one behind the other this solved that issue.

BLHEI 32 settings

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First ride.
I was shocked to find that first ride out everything worked like a charm. Tons of power, more than my foil drive assist plus using the same battery. I could foil on a 1400cm wing at about half power. I took it out flat water for about 25 min and was at 40% battery remaining. That was all e-foiling even though this is really an assist. I would say efficiency is the same as foil drive if not a little better. Much better than I was hoping with the flipsky folding propeller.

Current issues.
When I am on power and the propeller comes out of the water I lost all lift and the board needs to drop back down to the water for me to recover. I’m not sure if this is the propeller or maybe that my pod isn’t perfectly smooth. It’s very dramatic where as the foil drive just buzzes the prop but you don’t drop off your lift. I compared the 2 foil props (foil drive vs flipsky) and besides flipsky having more pitch the props are very similar. I have ordered a propeller king folding prop that should be here soon so it will be interesting to see if this solves the issue.

Thanks again please let me know if you have any advice on the build or have an questions.

[ak-foiler]

wow, awesome build. im am considering building something very similar to you. Im an electrician but not an electronics expert , but though reasearch on this page i think i can make it happen. do you have a sketch of your wireing diagram?

[Joka]

Hi! Thanks for your post! What do you need an bec for?

[damandan]

A BEC is needed when using an ESC. A BEC reduces the voltage and amperage down to a much smaller amount that won’t burn out the fragile components like the remote controller chipset. The alternative to a BEC is to have a separate small battery (like a watch battery) that powers the fragile components. In my case my BEC takes up to 48 volts and reduces that down to 5v and 3a output. This protects the remote control as you see in the wiring diagram.

[damandan]

Here is the basic wiring diagram I drew from memory. This is specific to the flipsky remote and other hardware I used above, but should be generic enough to use on other builds. Hope this helps.

[Joka]

Hey mate, thanks to your post i realized i need a BEC! i thought i can just plug the cable from my flycolor hcross into the receiver and im finished. Thanks a lot! I Emailed flipsky if i need a BEC with these components and they said no. But maybe its a missunderstanding because of poor wording or somthing…

[ak-foiler]

thankyou,

in reguards to the battery what is your reasoning behind getting 2 batteries { 2x 6s3p batteries }instead of the mboards 12s3p thats cheaper? is it the size of your enclosure? are you tyring to be able to fly with them? or is it so if you loose 1 battery cell in a pack its not as much of a loss?

ive read most of the builds that people have posted on here , but im pretty close to wanting to copy what you have, other than im not sure about weather to just gen the esc or the vesc . what made you chose the esc over the vesc?

i noticed you are using naish, i have a few foiling systems but will probably build this to work with gofoil. i have a m280 as well as a gl240 i used to learn on . im curius, do low aspect foils work well with foil assist or does it work best with high efficentcy wings / hi aspect?

I know i got alot of questions, but im starting to get pretty serious on doing this . i would buy one but at 3-5 k a pop , i dont have the cheese. i already have a hard time keeping up with both kiting and winging, but having all the foils and boards , spending a grand or so would be acceptible.

[damandan]

My main reason for going with 2 6s3p was size. Even as it is the battery dimensions are 5.7" wide by 7.9" long and only 1" high. That takes up a bunch of room. Optimally I was hoping for something in the 12s3p range that would fit, but their 12s3p is 14" long. These batteries may be overkill with a constant discharge of 135Amps but everything else seemed to be right on the edge of 80A max discharge.

I chose the ESC since it was much simpler to setup and program. If you looks at the BHLEI screens vs the VESC programming screens there are so many more options and also lots more pitfalls. Also the price is about half on a ESC depending on what one you choose. The downside is no battery life and other info can be sent to the remote (as far as I know). So to check the battery I have to look at the indicator in my box.

Regarding low/high aspect foils, I haven’t noticed any problems foiling either. Ive riden 5.6 aspect wings up to 9.8. The motor works great for both, actually low aspects are a lot easier to learn on. The difference really comes in when you are riding a wave without the motor if you want to do that, or pumping the high aspect will go further easier.

If price is a concern as it was for me too. I first got a older gen 1 foil drive foil assist plus on ebay for $2000. I thought that was reasonable, you maybe able to find one cheaper I’ve seen a few used for $1500. I wanted something with a little more push and wanted to see if I could build one myself, this seems to deliver both.

[damandan]

Yes no problem. You surely need a BEC glad you found it before you plugged it in the first time. Those components need limited voltage and amps. I got one on amazon but they are generic and pretty easy to find. Just make sure you get one that handles your voltage from your battery (for me it was 44 volts).

[ak-foiler]

thankyou for all the knowledge .

[seagull_nz]

Does the Flipsky prop bolt straight onto the FoilDrive Motor or does it need new holes drilled? I know a few people with broken FD props and the Flipsky would be a much cheaper replacement.