Hi,
What are your current hatch dimensions like L x W x H ?
Also, how do they compare to the Lift one ?
Looks nice, Di you calculate your costs alltogether in parts?
Hi.
I probably got $10k total in the two boards.
The first board was over $6k because I bought the Lift board and FR propulsion unit.
The second board was less then $4k.
These are rough estimates.
$1k battery
$1k board build
$1k foil
$1k for everything else motor, ESC, shitty maytech remote, enclosure, wires, miscellaneous stuff.
You could build a efoil for under $3k if you bought a cheaper foil, built a cheaper battery, and made a cheaper board.
But, I spared no expense! I have ridden with Lift boards and Fliteboards and I run toe to toe. I actually had to tow one back in. I wouldn’t trade either of my boards for a Lift board or a Fliteboard, so that’s saying something.
And with my bullet proof slingshot wings, I’m less concerned about hitting the bottom, and more versatile (3 different sizes).
3 Likes
Lovely build! Which latches are you using? Currently I have leaks from latches and looking to replace them with good ones!
Hey there, are you considering a folding prop for the foil sup / efoil mix? I have been thinking about using a oneway clutch (needle bearing based) in my shaft prop connection. Of course there will be some drag to spin the prop on the oneway clutch but I’m sure the folding prop has some drag as well. Sealing the oneway clutch will be the difficulty. I am using my 130L Gong Board for Wing surfing as well as efoiling. I just change the mast for this. I am also taking passengers along in the efoil setup. Currently the battery is still strapped on but i bought a rectangular hobie hatch which I am planning to install this fall. Hope this will seal sufficiently. Had some water intrusion into my battery suitcase this week and cooked some ml of water. No big thermal event unfortunately. I will for sure place some small common laundry room water detector in my battery case from now on to be sure. 
https://www.ebay.com/itm/124181777888
This is the same type Lift uses except this fits a 2.25" hole and the one Lift uses fits a 2" hole.
These latches are 100% water tight. Not a drop leaks through either of mine.
4 Likes
Hi.
Not a bad idea. Please let us know how it works.
Yes. I have a folding prop.
On sailboats the prop causes more drag if allowed to spin. So I the motors are designed where putting it in reverse with the engine off, locks the shaft.
And same thing with helicopters, and airplanes. A spinning prop causes more drag then a stationary one.
I was testing my new acrylic box with the marine connectors in the garage. Had little spark while connecting, I saw on an old post you were using an AS150 inline to complete the connection, were you still using that?
yes, I guess you are right about the drag while spinning. Same like the auto rotation sailing effect in helicopters. So wrong thinking about the free spinning prop. But regardless of all hydrodynamic solutions I see also the electric solution to have the controller regulate the prop speed to the board speed in order to spin just at the rpm which matches the current board speed for coasting. But this would require the speed information. So not really easy to achieve I would say.
Hi.
Yes. You need a anti-spark connector.
I use these. They are amazing, and easy to waterproof. Mine are 100% waterproof. Fits my 6awg wire.
3 Likes
Hi.
You learn to do this with the trigger. That is the second best way if you don’t have a folding prop. The load on the motor is next to nothing when you catch a wave, and use the trigger to just match the prop speed to board speed, no thrust and no drag.
That’s called “zero thrust”.
I see some water drips inside the box 
What have you done then ? Would you have a pict or two ?
I remember this method being first described by virus last July (2019). Not everybody understood at the time 
Does this method offer a totally invisible prop in terms of drag ?
This V_rot_mini might be automated with a micro wave sensor fixed on the mast or fuselage detecting the water flow speed. They do that on sailboats to send the speed to the board computer. For efoils, we need a proportionality table stored in the remote: V board (m/s) = K V rotation (rpm)
Read the post above.
Hi.
The key to zero thrust is finesse. It’s constantly changing as your speed changes. But, yes. This works. However, it’s not the same as a folding prop. With a folding prop you don’t have to concentrate on the trigger. You just forget about the motor and that allows / forces you to ride the wave, pump the foil, actually make the wave propel you. I never had that feeling when concentrating on the throttle and the zero thrust technique.
As far as waterproofing these plugs,
they are very close tolerance. I keep them coated with silicone grease. The way the plastic plug mates with the other half, a thin film of silicone creates a waterproof seal. Then you have to seal the back of the plug where the wires connect. Unlike other plug types, the water cannot get through from the back side (wire side). So, I just did several coats of Conformal coating on the solder connection and the wire, and wire insulation end to prevent water from going up the wire, or corroding the copper, or solder connection. This also prevents the voltage to making connection with water. You can test this with a voltmeter.
For the motor wires I use these:
The silicone grease also seals these perfectly. On the back of the plug on these however, you need to seal them or the water will penetrate into the contact side. To do that I solder, then Conformal coat, then seal with butyl rubber, and heat shrink over. Works like a charm!
6 Likes
Hi, he using sonar or which type of sensor?
Where are speed sensors for airplanes, but I’m not sure if they waterproof - I didn’t use it due price 
People using them on high over 1000m, where high humidity so possible that they could be used on our application.
I’m using flow water sensor on the end of ESC to detect if waterflow stopped for cooling ESC…
I very inspired by @maxime_ecn build so If you using something like this
I think you are able to put water flow sensor in tube and detect water flow speed
Hi guys.
Did some playing around in the small waves in Nawiliwili last week. The new SUP size board takes some getting used to, but it actually feels small and agile. I think I’m really gonna like it. I used the folding prop on this ride.
2 Likes
For people looking for latches. I purchased these GEM latches from ebay, to replace my Chinese latches. These work great. I had an issue with water leaking through the center shaft on my old latches. These don’t have that issue and work great!!!
Update!!! Added some pics. With the ebay Gem latches, included are the short backing plate. Gemlux website offers other backing plates if needed. You will notice I had to cut mine in half. Reason being is that I didn’t make my compartment very large and it was hitting the battery when closing. I could have just moved the latches more aft, but that would require moving locking plate/tab. There isn’t much force need when opening the lid. I also made a few plastic spacers to fill the gap between the lid and backing plate, just incase anyone ask. The locking tabs inside the board, you can just use a piece of plexiglass or in my case I just made a epoxy resin block and sanded it down.
3 Likes
Looks good Sean. I like the two tone look with the racing stripe!
Now, let’s go ride!
1 Like
A link to the ebay listing would be nice and might help other people to source them.