Windsurfing has experienced a major decline in popularity in the last few decades as the sport’s culture failed to cater to beginners at the same time that experienced riders largely shifted to kiteboarding. While it’s sad to see a once-popular and enjoyable sport lose its mass market appeal, it does present a unique opportunity for others as there’s cheap windsurfing gear all over the online classifieds now. [Dane] recently found that some of these old boards are uniquely suited to be modified into electric surfboards.
The key design element of certain windsurfers that makes this possible is the centerboard, a fin mounted on the windsurfer extending down into the water that resists the lateral force of the sail, keeping the board moving forward instead of sideways. [Dane] used this strengthened area of the board to mount a submerged electric motor, with all of the control electronics and a battery on the top of the board. The motor controller did need a way to expel excess heat while being in a sealed waterproof enclosure, but with a hole cut in the case and a heat sink installed on top of it, this was a problem quickly solved.
The operator control consists of a few buttons which correspond to pre-selected speeds on the motor. There’s no separate control input for steering, though; in order to turn this contraption the operator has to lean the board. With some practice it’s possible to stand up on this like any other electric surfboard and scoot around [Dane]’s local lake. For the extreme budget version of this project be sure to check out [Ben Gravy]’s model which involves duct taping two cheap surfboards together instead.

Electric scooter parts, meet surfboard :D. Very cool project indeed!
That looks like a really simple build, i like the pushbutton remote, its simple and waterproof buttons with fixed speeds are way easier to build vs a waterproof throttle
Fortunately windsups are getting cheap and easy enough that one can get into the sport without being exposed to the “sport culture”. In most sports the “culture” is just one-upmanship and besserwissering.
besserwissering?
https://www.urbandictionary.com/define.php?term=besserwissering
Never heard that one before!
Butt kissing? In some sort of germanic based language
Hilariously “Stand Up Paddleboards” (SUP) became a thing to absorb the manufacturing capacity for rigid boards by selling them to people who like to exhibit their balance, poise, and au courant nature…or something.
That said, there are a lot of nifty surplus-board projects with motors including some sit-down multiple board planing boats with outboard motors.
Windsurfing in it’s heyday had a fashion/elitism problem; if you weren’t constantly upgrading to the latest gear and being more of a jock about it, you weren’t cool, but that drive left beginners and casual sailors out in the cold. So the manufacturers and dealers were mainly serving the $$$/adrenaline side of the market… and now there’s way more cool and adrenaline in kitesurfing. (not to mention that you can take all your kitesurfing gear in a knapsack on the bus).
Peak longboarding (80s to 90s) also had the same problem as fiberglass sailboats… they last decades with care! Which means not much of a steady market in replacing wornout gear. (sails being the exception; they wear out or blow out)
This motorizing project is definitely a cool use of an unwanted windsurfer. But, all things considered, I’d actually rather just be ….sailing a windsurfer. (SUPs are sort of cool too, but again I’d much rather just get out in a kayak or canoe. Faster, easier, more comfortable…)
Wonder what kind of autonomous survey drones you could make out of these things. Something like the SeaCharger but as a short range fleet for lake and river surveys. Puttering along at a safe sane 5 knots multiple drones could produce a fairly high resolution bottom images every two or three months. Which would be great for body recovery operations because you’d have an up to date baseline image of the bottom topography. Silt build up mapping around intakes for reservoirs and dams might benefit as well. I’m sure there’s a COTS fish finder that produces useful sonar image files.
Bottom line, this is an excellent blank slate drone platform.
Which of course means there’s the weapons aspect as well. You can weaponize just about anything so that’s not much of an imaginative jump. For situations like Ukraine though, I could see a “cottage industry” of makers turning out disposable swarms of these to make navigating contested waters an utter nightmare for any one they didn’t like.
It looks super fun and affordable too, but that propeller is slashy slashy yikes!
Yeah, windsurfs have the daggerboard there and boats have open propellers, but still, this looks like asking for trouble.
Windsurfing is not dead