”The barge” efoil build

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larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 24 2020 10:32am

Got standing today, it doesn't lift yet but it was very close. I'll try some different props and higher current :D

The connectors melted in the box so there's some heat to take care of already now :wink:

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amberwolf   100 GW

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Re: ”The barge” efoil build

Post by amberwolf » Jul 25 2020 1:37am

If it was just the connectors and not the wiring, you just have too high a resistance at the connector.

Looks like bullet types?

Could you tell if the damage started at the connection, or at the soldered ends?

If it was at the connection, then you'll probably need a bigger connector.

If it was at the wire-connector junction, then maybe something using a crimp instead, or a better way to ensure full connection between wire and connector?

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 25 2020 3:20am

ugh, i was using what was on the controller when i got it :wink:
don't ask what it was but i can say it was a bit underspeced (i'm SFOCing) :D

i've soldered on fresh 8awg wires and xt150s now

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 25 2020 9:33am

first flight today :D :D :D
Once up on the wing it's a lot harder to balance and it speeds up quite a bit :D

I smacked into the water like 50 times so i feel quite beat up but still extremely happy with this build, three weeks to build a functioning efoil from scratch is not bad :thumb:

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 26 2020 1:32pm

It's time to summarize this build :D

Costs:
wing assy 400 eur
epoxy 100 eur
glassfibre 50 eur
XPS 30 eur
3d print thread 30 eur
cables 15 eur
throttle 20 eur
resistance wire 10 eur
dimmer 25 eur
PSU 75 eur
Plywood 20 eur
enclosure 80 eur
connectors 10 eur
battery module 150 eur
80100 motor 150 eur
controller was borrowed, estimated 200 eur
total 1345 eur

Effort:
Less than anticipated :D

It's been a blast! :bigthumb:

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macribs   1.21 GW

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Re: ”The barge” efoil build

Post by macribs » Jul 27 2020 12:45pm

Very cool, forgot to post in this thread so I didn't get notified when you kept on posting. Luckily I remembered as I saw your nick in another thread.

Congrats on getting it working. Now to dial in the controller, and learn the balancing act while flying. This looks like a ton of fun.
Did you check the weight of the complete build?

Man you are gonna have tons of fun on that board.

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 27 2020 1:52pm

I’ll weigh it, good idea! I can already find some optimization points, cutting some kilos won’t be difficult. It’s a bit overbuilt now.

I think the foil could be placed more rearwards and board be shorted from 180cm to 150 or so. It should be a bit more rounded off course, now the wind gets it. I’d like it a bit wider also for those accidental nose dives.

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 27 2020 2:23pm

Checked efoil weight: 31.5 kg (ready to go with everything on it)

The gong wing, fuselage and stab alone is 3.5 kg, a lot could be saved by going to a different foil.

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 29 2020 1:31am

Some things will be updated on the efoil when i’m back home:
-Arming switch to be moved to where it doesn’t get knocked off
- Heat exchanger plate for controller in side of enclosure
- Small wall (hot glue) on bottom of enclosure for stopping battery from shifting during splash

Motor updates
- filling magnet spaces on rotor
- filling stator slot openings
- changing bearings to stainless

Waterproofing throttle
Charging port

.. and lots of riding! :D

John in CR   100 GW

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Re: ”The barge” efoil build

Post by John in CR » Jul 29 2020 11:10am

larsb wrote:
Jul 25 2020 9:33am
I smacked into the water like 50 times so i feel quite beat up but still extremely happy with this build
Congrats on getting it flying. We've gotta come up with a multi-foil design that flies with stability but still leans to turn, something anyone can ride.

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Jul 30 2020 1:11pm

I don’t think it’s really so hard that it’s needed, i just need some practise :D I think the key is to have the board planing and just do small lifts/flights at first, then the water just catches you without a crash instead of smacks you and you get a lot more done :D

Btw, i saw a video where the surfer dude said that the foil i have is so stable that even a newbie would find it boring in one hour. Can’t say that i agree on that! :D

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Aug 01 2020 12:57pm

Improving the heat management of the controller: mounting a 400g alu block with heat paste between the two. Simple, crude but effective for a while :D
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ossivirt   10 W

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Re: ”The barge” efoil build

Post by ossivirt » Aug 01 2020 1:41pm

larsb wrote:
Aug 01 2020 12:57pm
Improving the heat management of the controller: mounting a 400g alu block with heat paste between the two. Simple, crude but effective for a while :D
27DDDC34-DD3C-4ACB-889D-C1E9926A684D.jpeg
That reminds me of a guy from other forum that mounted about same sized block of copper to his cpu and was asking why temperature goes up and performance down after few minutes :lol:. Any video coming where we can see how the efoil performs and how epicly you fall from it? :mrgreen:

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Aug 01 2020 1:52pm

Block will be connected to the outside water through an alu plate so the heat has somehere to go, if that doesn’t work i’ll get active water cooling. I like simple systems so it will have to evolve only as needed :wink:
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And.. I’ll post videos when i’m at pro level :mrgreen:

larsb   1 MW

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Re: ”The barge” efoil build

Post by larsb » Aug 03 2020 5:34am

Made a cradle for the controller with some angle brackets, to keep it in place during riding and maintain heat exchange to the outside of the box.
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