Electric Surf Board

[srn]

45mm nozzle, 76 diameter prop, with 70mm pitch

how about your water inlet ? My prop is 60mm. This could be too small

 

[chris_kline]

inlet is equivalent to about 80mm diameter.

i think the 60mm prop should be fine, whats the pitch of it?
just reduce the nozzle size to get more thrust, it will make a huge diference.

4kw @ 10000 rpm is very low power for that rpm. mine consumes about 10kw at 10'000rpm
ive found, going over 14000 rpm tends to cavitate on both my boards

 

[srn]

inlet is equivalent to about 80mm diameter.

i think the 60mm prop should be fine, whats the pitch of it?
just reduce the nozzle size to get more thrust, it will make a huge diference.

4kw @ 10000 rpm is very low power for that rpm. mine consumes about 10kw at 10'000rpm
ive found, going over 14000 rpm tends to cavitate on both my boards

Pitch is 60mm.


My biggest issue is the sealing of service hatches. Do you guys have good solutions for that ?

 

[chris_kline]

ill post a photo tomorrow of what i did with my hatches.

basically i just had a rubber gasket cut for me by a company who cnc cuts gaskets for plumbing and oil industry etc

60mm pitch is a little low, especially for a 60mm diameter prop, you would need to get that nozzle pretty small to create enough thrust for planing, something like 40mm. but with a small enough nozzle, it will be fine

 

[chris_kline]

heres a photo of my hatch, aluminium flange, with a rubber gasket, and thumb nuts for fastening it down

 

[fabianpusch]

My board has around 110l.
@10000 rpm I also need about 10kW, so it seems that your jet has a lot of cavity issues.
To seal your compartements use a soft tape made of Pvc....I have bought this from a reseller of RC controlled boats.
It is a quick and easy solution.

 

[FlorianAirs]

Hello,
I am from Germany and Reparing old Lampuga Air and Boost, if you have problems or questions just contact me :wink:
also building a electric surfboard myself with tp power 100/105 and vesc 75/300.

 

[chris_kline]

Hello,
I am from Germany and Reparing old Lampuga Air and Boost, if you have problems or questions just contact me :wink:
also building a electric surfboard myself with tp power 100/105 and vesc 75/300.

hi florian

thats cool. would you be willing to post some photos of the lampuga boards internals, like the esc motor, wire lengths, battery, jetpump, heat exchangers etc

would be very interesting to see exactly how they overcame some of the problems

 

[FlorianAirs]

Hello ,

i think i can post some pictures because the company is not anymore in buissines.
the setup from boost:

14S20P LG cells
MGN 400A
Don't know the brand of the motor but 95mm diameter
MHZ 64 Jet drive

setup of the AIR

14S20P LG cells
MGN 250A
Lehner torquestar 7050
MHZ 64 Jet drive

some pictures of the boost:

 

[srn]

I thought the boost has an Torqstar 3 7050. Is it an inrunner on your pic of the boost motor ?

 

[FlorianAirs]

the motor from the boost is an outrunner

 

[Bazaki]

I do have a new lehner torqstar for sale if anyone is interested. 7040 watercooled 320kv

 

[aethyr]

Florian,

Can you post larger pictures of the boost internals? The small pics are kind of hard to see the details

 

[madin88]

Florian,

Can you post larger pictures of the boost internals? The small pics are kind of hard to see the details

Yes please, and from the motor
It looks a bit like a larger version of the Torqstar..
would be interesting to know more about it, like which brand and where it could be bought.

 

[fabianpusch]

Wow, that looks really like a homemade production.
I will post a few pics from my board.
Will do it on the next weekend.
We are in Corsica and I will ride it for 2 weeks

 

[Blackdavid]

Hello guys, just one quick question
That graupner jet 5, would one of those have the capability to move a surfboard with a 220lbs rider on the water? With a suitable motor, would it flow enough to plane on the water?

 

[Bazaki]

No. Too small

 

[Blackdavid]

No. Too small

What would you suggest?
Maybe if i put two of those, and twin motor?

 

[bigbore]

Did you see this?
https://www.mhz-watercraft.com/shop/en/jets/497/jet-64-for-electro-surfboards

It was used on old Lampuga Boost and Air

 

[fabianpusch]

Hey at all
Today I have reached 23 MPH....was a good run in the early morning.
I have promised to send some pics...but how can I do that from my Android mobile?
Bye Fabian

PS the mhz 64 is a good choice

 

[ropower86]

@fabianpusch,

Hey at all
Today I have reached 23 MPH....was a good run in the early morning.
I have promised to send some pics...but how can I do that from my Android mobile?
Bye Fabian

PS the mhz 64 is a good choice

I think you need to upload the pics from the computer. Record a video and post a link. Also, I have a jet 64 but the only thing stopping me is the battery current is weak and the lids which I am having hard time making. Meanwhile, I bought an electric powered bodyboard in mid-summer.

 

[chris_kline]

hit 75 kmph yesterday!
heres a video doing not quite full speed around 65kmph
https://youtu.be/BENxS1iLGjk

 

[ropower86]

hit 75 kmph yesterday!
heres a video doing not quite full speed around 65kmph
https://youtu.be/BENxS1iLGjk

Your skills are madness!!! You really have all the tools to make Sh## happen.

 

[fabianpusch]

https://youtu.be/hzqdDyQC6nw

Greetings from Corsica.

Your petrol powered board is amazing....really fast. Great job...and a perfect lake with best conditions. Where is it?

 

[chris_kline]

https://youtu.be/hzqdDyQC6nw

Greetings from Corsica.

Your petrol powered board is amazing....really fast. Great job...and a perfect lake with best conditions. Where is it?

that looks awesome, really smooth!
how much run time do you get per charge? what size battery were you using?