Search found 95 matches

by chris_kline
Oct 20 2019 12:43pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

srn wrote:
Oct 20 2019 5:56am
I have a 3D printed steel impeller. Ordered it at i.materialise.com
There you can upload your file and instantly get a price.

The print quality is impressive
great thanks, i will try them.
by chris_kline
Oct 19 2019 2:28am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

i can cnc the crank case, but the cylinder/block has exhaust/transfer ports that can only be achieved with either wax loss casting, or dmls. i got some parts quoted dmls a few years ago for my company, was cheaper back then to wax loss cast, but both were extremely expensive. i was wondering if the ...
by chris_kline
Oct 18 2019 1:48pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

That sounds cool, I am trying to animate a PhD in fluid technical systems and my old connections to Formula1. I think building up a jet is not impossible. The hardest thing is spending money for the itereations and the prototypes. By the way, we have multi jet HP printer and also some DMLS metal pr...
by chris_kline
Oct 05 2019 9:38am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

lehner 7050 with 5 windings

76mm prop with 70mm pitch, 52mm nozzle
by chris_kline
Oct 05 2019 7:20am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

yeah 2 thousand euros is a little on the pricey side
by chris_kline
Oct 05 2019 7:19am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

i was running 20 degrees, and the fets were getting close to max temp, then i increased to 25 degrees, and the fets were cooler by about 8 degrees.
im running cooling from the jet drive, but it pumps a lot of water through the system through 10 mm diameter hose
fets are stable around 60 degress c
by chris_kline
Oct 05 2019 6:43am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

yeah, check the waterflow, the fets on mine never get hot, also what motor timing are you using? more degrees timing keeps the fets cooler, but gets the battery and motor a little hotter.
how much did that battery cost, looks like the proper shiz
by chris_kline
Oct 05 2019 6:10am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

Hi Chris, No it is a 14S1P configuration. The cells are KOKAM cells, each cell 53Ah. The caps are okay, the internal temperature of the MGM says to hot...and then the power is automatically reduced. How did you solve the cooling of the capacitors, sounds really interesting to me. i have watercoolin...
by chris_kline
Oct 05 2019 4:38am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

so you were running a 17p battery? assuming your cells were 3000mah?
by chris_kline
Oct 05 2019 4:37am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

what part of your mgm was getting hot? the fets or the caps? i was having problems with my caps, so i put a huge capacitor bank with watercooling on them and that seemed to solve it. in the end i was having problems with my batteries getting hot, especially if i full throttle to 54 kmph, and some of...
by chris_kline
Oct 05 2019 4:12am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

fabianpusch wrote:
Oct 05 2019 1:05am
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?
by chris_kline
Oct 03 2019 6:22am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

hit 75 kmph yesterday!
heres a video doing not quite full speed around 65kmph
https://youtu.be/BENxS1iLGjk
by chris_kline
Aug 28 2019 2:57pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

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,...
by chris_kline
Aug 11 2019 10:10am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

heres a photo of my hatch, aluminium flange, with a rubber gasket, and thumb nuts for fastening it down
by chris_kline
Aug 09 2019 10:51am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

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 enoug...
by chris_kline
Aug 09 2019 4:39am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

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 rp...
by chris_kline
Aug 09 2019 2:59am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

45mm nozzle, 76 diameter prop, with 70mm pitch
by chris_kline
Aug 08 2019 12:32pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

my electric jetsurfer has about 150l of volume my gas jetsurfer has about 90l of volume. my gas jetsurfer sinks if im not moving, but i wanted it smaller to be more maneuverable. if you decrease your nozzle diameter at the small end, you will get a lot more thrust, and will get on the plane almost i...
by chris_kline
Aug 05 2019 7:26am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

yeah, those Esurf boards look very well made, next gen stuff.
but they cost like 20'000 so for that money, you would expect the best!
by chris_kline
Aug 03 2019 9:01am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

yeah i contacted them when i was in the middle of my troubles with mgm.
they said they werent really able to get the erpm needed
by chris_kline
Aug 02 2019 3:00pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

mould for the board? no this one was hand made, from expanded polystyrene foam and wet lay carbon like the last one, i just got a bit better at doing it this time :D the motor compartment was made with a mould though, and prepreg carbon, but i dont have a big enough autoclave for the main board to fit
by chris_kline
Aug 02 2019 2:00pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

looks well made, would be interesting to know what the max erpm is on that. im thinking it would need a watercooling heat exchanger on those fets for a surfboard application though. thing is on watercraft you are operating at a high load constantly, its like gong uphill all the time. about mgm, mayb...
by chris_kline
Aug 02 2019 4:59am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

yeah, well they must have figured out a way to stop them exploding. maybe they went with external watercooled caps banks also, or maybe they just tuned the resonance out of the caps with specific wire lengths and battery configs, and esc settings. through a combination of increased motor timing to m...
by chris_kline
Aug 01 2019 4:06am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 725
Views: 170102

Re: Electric Surf Board

eventually i got so sick of the problems with the esc, mgm, and the cells, that i built a gas jetboard from a 2 stroke racing kart engine. i know this is an electric power forum, but i hope you dont mind me posting a couple photos and video of the second jetboard i made. here it is part way through ...