Foil Drive Assist, DIY

Something unusual happened during today’s session. After a few pop-ups, the power dropped to the point where it couldn’t lift the foil. What a bummer!

  1. Nothing changed since the last successful session.
  2. There are no mechanical or electrical issues.
  3. I’m stumped. But next time it happens, I’ll try reconnecting the battery—it might be some kind of ESC protection function.

I’m using a 6384 motor with an Xcross 160A ESC with fans, and a 12s3p battery setup. You can check out the build here.

I can’t remember where it was asked about how I build my 12s2p, but I have changed the layout to keep the battery leads as short as possible. I forgot to take a picture of the top before I sealed it up, but a couple pics with a drawing. I built this for a buddy this weekend. I used .2mm nickel strip and doubled it up on the single row, so hopefully this will give the least voltage drop and heat. I also 3d printed tubes for the BMS wires to go through the pack so all the wires would be at the top. All separated by kaptan tape and fish paper where the overlap. A couple pics won’t load so I’ll have to convert them.


7 Likes

I wanted to do something similar but do a copper nickel sandwich on the series connections and a single nickel strip on the parallel to keep the resistance lower on the series vs parallel . Don’t know if it makes any difference on just a 2p battery ?

It will work and it is a clean build, but based on the power those cells supply, its is borderline. Use more for your next build or change layout to avoid single strip connections. This kind of ressource chart can give you a good idea :

I completely agree, but I’ve also built a 12s2p with just .15mm nickel strip and haven’t had any issues hammering on it, but probably getting voltage drop. So, double upped .2mm should be plenty, but maybe add one more layer of .2mm.

That is the best layout I could think of. Do you have a suggestion for a better layout? I would definitely build it. Keep in mind that it has to be in this layout for the box size.

That is super useful. I had not thought of that configurations for a 12s2p. This would replace my 8s3p perfectly in the Camden box I use.

2 Likes

@nekitesurfing …my.mind boggles everytime i see a battery diagram…i was never any good at puzzles!!
Agreed…a great more powerful solution for those of us using the Camden Boss boxea !!!
K

1 Like

Super interested in the parts for the first pic with the yellow prop. Is that the BOM you listed just after this post?

Basically I now want to build the smallest possible assist (for wingfoiling) with the least weight on the board (smallest 6s battery to last several starts, small esc without cooling, etc) and least drag in the water (6374 or 6384, single cable through board, mounted high on mast, folding prop, etc.). If I can get the size down I may even build a cavity into the mid size board I’m about to build.

How would you use it for wingfoiling?
I have a dream to learn and to use wingfoiling (or kite, or parawing) in light thermal wind and even with a small board using the foil-assist to help get up.
I did a few tests, but couldn’t figure out how to combine them.
So when you manage to do this, please tell me.

Ha. Yeah. I’m setting myself up for lots of struggles and learning, but that’s part of the fun. There are few videos of guys using assists for starts and building up apparent wind. That and using it to ride to spots out of wind shadow and back in through wind shadow is part of the dream for me. I’ll pop in next year to report how it went :wink:

1 Like

Did you ever find anything for a high current 3 pole connector? I too am just about to start a new board build and would love to have the motor-to-esc connection running though a hole in the board rather than directing it under and over the board.

There have been some clever custom solutions here with individual bullet connectors, etc. but they seem to add up to a significant diameter. Would love to keep the hole through the board as small as possible.

Also: It seems like the original foil assist had motor cables combine into a single 3 conductor cable near the motor. This cable seems like it’d be around 14AWG. Or at least much less than the large motor lead wires. How is this possible without overheating? Is this whey some seem to be getting away with MT60’s? The math doesn’t add up :wink: But curious how others are handling dropping down to a single cable between esc and motor.

For science, I tried the combination of wing foiling and an efoil assist and found it really difficult to balance the large force of pulling/balancing myself with the wing combined with the fine trigger dexterity on the trigger. There was also extra weight from the assist system which I didn’t like when wing foiling and so I had more fun doing one then the other than combining them both together.

1 Like

Awesome to hear but sad that it didn’t feel good. Would love to know more about your setup: Board size/volume, wind strength you were out in and what your assist system is roughly.

Maybe the parawing will be answer (when Gong develop low cost version)

Born Kites WaveStar or FoilStar

image

1 Like

Weight: 140lbs / 63.5029kg
Board size: 5’
Volume: 95L
Gong link to board/foil kit GONG - Pack Wing Inflatable HIPE First X-Over Easy – GONG Galaxy
[Click Size Guide for details]
Foil Assist details: Light Foil Assist Project - Cocoa Beach, FL

Conditions: Intracoastal, 17mph winds light chop on water, ~4"
Talent factor: Good enough to wing in each direction, just learning how to jibe, can efoil without putting the board down for 5 miles.

I suspect that something like this shortened up would work the same as the marketed parawing, it looks like the parawing just has a deeper chord, but I bet there’s a trainer out there with similar specs.

Cost is ~$200 vs $900,

vs

Or am I missing something there?

It needs to be a single skin kite. The brm is massively overpriced for what it is but the only single skin kite that I’m aware of that goes up to 5m2 that could be modified to fly on the short lines is the fly surfer peak. This is still quite expensive, especially if you are then modifying it.

2 Likes

hq kites kick 180 1.2m2 for when it is nuking, with custom bridle it works well, but untested in water yet.
older petter lynn uniq tr ? unavailable as of today.

2 Likes

I have been thinking about an addon program in the remote/receiver to be activated on demand. It’s purpose is to ease the multitasking of managing wing and throttle at the same time…
Here some options:

  1. When program activated, pressing any amount of throttle will trigger a preset throttle percent.
  2. When program activated, pressing throttle once will trigger run for a preset amount of seconds and preset throttle percent untill timer is over or it cancelled by pressing throttle or no reception as usual.

My left arm on front of the board, right arm holding the remote and picking up the wing, then holding it in the air in the neutral position. So here the problem of managing trigger and wing presents itself.
If picking wing using the left hand, right hand will manage the remote and lean on the board front. Again, hard to do these two actions with one hand.

Maybe there is a solution to control trigger with some other body organ… Like a mouth

It will be cool to develop fully automatic get up solution - it will sense the speed, height and adjust throttle till on foil.
Or semi automatic - it will rump up the speed in fixed levels till motor out of the water - maybe it can be sensed by sudden rise of motor speed or fall of current.

Pressure sensor remote:
'Remote control GLOVE

Pushing trigger with tongue:
'Remote control GLOVE - #22 by lishine

Foil drive with the wing experience:
'Winging with Foil Drive Assist | Foil Drive Blog – Foil Drive Pty Ltd