Boards for eFoil

Very large space for ESC batteries and others.


Hi @MaxMaker, do the Cabrinha Double Agent masts have much space to fit all the cables?

They have enough for 3x 8AWG. My cables are about 6mm in diameter including the silicone. So there is enough space.

Thanks @MaxMaker!
The 3 cables that are currently attached to my motor are 7.5mm in diameter…
Do you think they would squeeze through?

Hey Pacific,

Wondering if you had any input on the optimal mounting position of the mast on the board.

I just got my board in and have a design that will allow for the board to be disassembled when transporting rather easily.

But before I go cutting into the board I was hoping to get input from someone that has their design up and running.

As soon as I get mine up and going I will post pictures of the design

Hi Tim, my mast center is 48cm from the back tip of the KRace70. Here some more pics with measurements for battery and esc box. Measured from back.


Awesome that is similar to where I planned to mount the mast. I planned on mounting it even with the two slotted fin mounts that come standard in the board. Also did you fiberglass those cutouts or just use an adhesive sealant to protect the newly exposed interior edges of the board from absorbing water

depending on the front wind size and the lenght of the board, i beleive you need to have your legs in between the middle curve of the front wing , correct?

@pacificmeister: your board is 190X70 i read (?) what is the tickness and the liter please ?

At first I just routed slots for the tracks, no cloth, just resin. See That held up great for many rides …until I hit that rock at low tide here and it all broke out. I then used a block of high density foam and a piece of cloth underneath, see here:

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78 liter. Here is a chart if anyone is interested in specs of old kite race boards out there. Most of them are collecting dust in someone’s garage now. They make good efoils:

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Thank you ! You are able to make stand up start with 78l ? on my board 98l i go down directly

Just a practical reminder from what I’ve read:

  • V = Board volume. At the beginning, you need a board that floats (safer in case of failure and faster learning curve) = (your weight in kg + 30 litres) x 1.1 for board nose bevel compensation (1).
    Ex: for sbdy who weights 80 kg -> board vol = 110 x 1.1 = 121 litres. Then the volume can go down depending on riding skills and confidence in gear.
  • P = Mast position : centre of mast at 20% of board length measured from board rear.

Board dimensions: L x W x T = V (so parametric). The shorter, the more manoeuvrable …

  • L = Board length: Lmin = somewhere between your chin height up to your own size
  • W = Board width: The largest value between Wmin1 and Wmin2 where:
    Wmin1 = distance between your shoulders + 10 cm (comfort criterion)
    Wmin2 = If you decide to insert a waterproof box inside your board = box width + 20cm that is Box width + 10cm on each side (board structural resistance criterion)
  • T = board thickness = V / (L x W)

Board shape: cannot be more simple
Top surface = flat surface
Bottom surface = flat surface (a V on the rear third seems to make the board stick to the water surface)
Board edges: small radius (20% of T the board thickness) to keep the volume. Avoid lengthwise bevels on bottom surface like kitefoil boards that make the board more unstable.
Board scoop (curved nose up when board seen sideways) : none needed but there must be a bevel to make water touchdowns more friendly :
Length of bottom surface = 0.8 x length of top surface.
(1) This 10% of board volume loss has been compensated above with the 1.1 factor in the volume determination.



Example for a comfortable ride with waterproof box on top of board.
John 75kg, 1.80 m, shoulders’ width 60cm (0.6m)
V = (75 + 30) x 1.1 = 116 L= 0.116m3
W = 70 cm = 0.7m
T = 0.116 / (1.8 x 0.70) = 0.092 = 9.2 cm
Nose bevel: board top length = John’s height = 1.8 m
Board bottom length = 1.8 x 0.8 = 1.44m

For a comfortable ride with waterproof box inside the board (box dim = 30 x 20 x 10cm = 6 L)
To preserve board structural strength, you have to add a minimum of 2.5 (1") cm of EPS foam under the box.
So new board thickness = Box thickness + 2.5cm. (1")
In the above example, new T = 10 + 2.5 = 12.5 cm
New board volume = (1.8 x .7 x 0.125) / 1.1 = 143 L - 6 L (box volume) = 137 L with nose bevel (hence /1.1)
So adding a 6L waterproof box adds 21L to original board configuration with box on top.


I’m looking for some input on which board would be best to repurpose for an efoil board. There aren’t any surfboards for sale around where I live and I don’t want to build a custom board until this winter. My options are to buy a used wakesurf board (66"x23"x1.75") or I can get a used windsurf board (~9+ feet). I would prefer to buy the wakesurf board but I’m not sure how much of a pain it is to have to always start laying down due to how thin it is. On the contrary, my concern with the windsurf board is that the weight and length will make it clumsy to ride. Any input/ thoughts would be appreciated.

board to foil or board to learn to foil?

it is depending on your weight, skill, foil wing , needs to put the battery inside the board…

i learned with a tamuka v100, which is a large wing i beleive, the weight is 130kg all included with a sup board 98L (244x77X10), i took me about 4H with some wakeboard skill to be up

first start was hard, now is easy, stability is ok with 70cm wide i would prefere 80, lengh (244) is to long espacilly with wind BUT it assure you smooth landing , i’d never fall over when touching the water

i use this board because it was cheap and sold close to where i live, i really wanted to get on the water, then i think i will never make it and i will need a 150L board, then i was up so i want a smaller board to carry in my car, then i got speed and crashes (sideway), and i think it 's nice with the lenght that the noise of the board doesn’t go down to deep in the water, so i am keeping my board like that this year

so i guess there is not ONE board, and you will change your mind when you ride it

Thank you for the feed back. I’m new to foiling but I have experience in other water spots. I too will be using a takuma wing (a Chinese clone of one). I was planning on just strapping the electronics to the top while I learn. I just want a board to learn on for a few months before I figure out what I like and build custom. From your response it sounds like my best option will be to choose a small wind surfboard rather than using wakesurf. Thanks!

Done and ready for assembly!!!


New efoil board and testing on the water video posted on this thread: Share your builds here!

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What are you guys using to attach the foil to a board that wasn’t built for a foil? I’ve been looking at the stick on “Foilmount” but wondering if there are any other options.


Here’s a discussion on one option…