Search found 66 matches

by srn
Aug 29 2019 2:07pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

I thought the boost has an Torqstar 3 7050. Is it an inrunner on your pic of the boost motor ?
by srn
Aug 09 2019 6:20am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

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 r...
by srn
Aug 09 2019 3:50am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

chris_kline wrote:
Aug 09 2019 2:59am
45mm nozzle, 76 diameter prop, with 70mm pitch
how about your water inlet ? My prop is 60mm. This could be too small :idea:
by srn
Aug 09 2019 1:40am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

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 ...
by srn
Aug 07 2019 2:40pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Did some water tests. Two major problems: 1. Sealing of my polycarbonate glasses is not good. Had water in my board, thats why I had to stop testing. 2. I am too heavy :oops: In my design phase I thought that it will produce enough lift when accelerating. So I designed 100l of volume. The board weig...
by srn
Jun 24 2019 12:49pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

I did some progress and now only wait for vacation to do some water tests. I especially modified my batteries. Now running on 48 pcs 20700 liion cells, 12S4P. Each parallel pack with own 60A BMS. I also build a power distribution board, where I put in all battery packs and charger (for charging all ...
by srn
Sep 05 2018 12:06pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

hello guys, i am still testing in my small pool. now my remote control is working fine. Also the new propeller is doing a very good job. here my current MGM log. I wonder that I have really small power consumption at 10.000 rpm. At the moment I limited the MGM to 10k rpm for testing. Will try 12k rp...
by srn
Sep 03 2018 12:36am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

ropower86 wrote:
Sep 02 2018 2:24pm
How much did it cost you to 3d print in metal?
I ordered a 62x62mm. They said that it will shrink 2-3% after thermal treatment and finally I got a 60.5 x 60.5 impeller.
It is ~95€.
by srn
Aug 31 2018 9:36am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

toto44 wrote:
Aug 30 2018 10:04am
Hello SRN

what pitch does your impeller have? Did you balance it?
Hello toto,

the pitch is 60mm or equal to D if you scale it.

I have not balanced it yet.
by srn
Aug 30 2018 6:44am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

madin88 wrote:
Aug 30 2018 4:37am
how much did it cost?
I ordered a 62x62mm. They said that it will shrink 2-3% after thermal treatment and finally I got a 60.5 x 60.5 impeller.
It is ~95€.
by srn
Aug 30 2018 3:37am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hello,

i changed my carbon impeller to a 3D-printed steel impeller. It is really impressive quality and less vibration.
IMG_3664.jpg
today I will make first measurements of power consumption. Will provide results later.
by srn
Aug 20 2018 1:56am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hello toto44,

good video, looks like a lot of thrust for this small motor. Do you have a log of motor/esc power during this run ?
by srn
Aug 16 2018 4:14am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

I already reduced voltage to 8S which did not make any difference. The MGM controller is tracking the "input current" and the "peak current". I thought that the Battery to ESC current is the "input current" ?? This one is very stable so if I am right, there is currently no need of capacitors or shor...
by srn
Aug 13 2018 1:52am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Really strange picture. I think you are right with the remote input, seems to be 0 or 100%. What about your cable lengths? Do you use additional caps. About settings, try to increase the acceleration time...to 3 or more seconds. Next use a servo tester as input and check everything again. Hello Fab...
by srn
Aug 12 2018 6:39am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Here my graph after adjusting shaft and reducing system voltage from 60V to 30V.
Controller 2 history 2018-08-12 13-34-59.jpg
The peaks are still very high. I am also wondering about the input request. Seems that my remote control is only sending 0 or 100%.
Will check this before next try.
by srn
Aug 12 2018 5:39am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Frizzo wrote:
Aug 12 2018 5:10am
Hi Srn,
With what battery configuration did you go btw?
Hello Frizzo,

I am currently using the Turnigy Heavy Duty 4S 5Ah Lipos. They are rated with 60C (120C burst).
At least for testing they do a good job. Have them in 2S2P now.
by srn
Aug 12 2018 1:06am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Yes I ordered directly from Lehner, in april this year.
by srn
Aug 11 2018 4:56pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hello Mgivens,
my motor looked already like this when i got it. I also wondered, because i expected black-purple. Dont know but i dont need color on it.
B11178D6-338A-43FA-9A85-EC61EC0FD1F7.jpeg
by srn
Aug 10 2018 3:36pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

The Impeller should be too small (60mm) for the Lehner Torqstar 7050 275kV.

I found that there was high tension on the shaft. Will adjust it again and do another try.
by srn
Aug 09 2018 3:40pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hello Fabian,

do you know why this peaks can occur ? You see on following graph, that the average input current is 10 - 20 A.
Peak current is at motor side, maybe I have too fast acceleration ? I will reduce it and try again.
Controller 2 history 2018-08-09 22-32-24.jpg
by srn
Aug 07 2018 3:32pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hello guys, here some updates of my project: Today I made first water tests in a small pool (after fixing all sealing issues last days). It worked very well, also the water cooling, which I made according to Frizzo's suggestion. IMG_3577.JPG Here two log files of my controller. The peak current look...
by srn
Jul 23 2018 12:09pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

bigbore wrote:
Jul 23 2018 10:03am
The water is generally drawn through the outlet nozzle with a radial outlet
How about salt water, sand and dirt ? Anyone who had problems with direct cooling from nozzle water ?
by srn
Jul 23 2018 6:45am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hello,

my board is finally running (atm only dry for testing).
Now I am thinking about cooling. I have the watercooled Torqstar 3 and the watercooled MGM 40063.

How do you get cool water into your Motor and ESC ? Do you use external water or maybe a closed internal water circle with pump ?
by srn
Jun 05 2018 4:35pm
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hi & good morning Longtime full load is about 240 Amps for 5 seconds. Not too much - I think the problem will be the cable lengths from the battery to the controller. There are indication high internal peak currents (about 600Amps) and this is too much for the caps. Install the controller as close ...
by srn
Jun 04 2018 1:13am
Forum: Electric Watercraft
Topic: Electric Surf Board
Replies: 718
Views: 169387

Re: Electric Surf Board

Hello Fabian,
did you read the log of the ESC ? Was ist long time full load? Too hot? High peak load ?