Electric Surf Board

[fabianpusch]

At the moment I am using 15 degrees.
What timing have you set up?
The battery was with a special prize 2000 Euros for 17 cells. But add on there is the BMS, which is nearly 600 Euros.
So not a cheap solution.
Have you installed an additional waterpump?

[chris_kline]

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

[chris_kline]

yeah 2 thousand euros is a little on the pricey side

[fabianpusch]

Chris which kind of motor is your actual model?
I will try that timing setting the next weekend.
I am really looking forward to see an influence.

If you are interested in such a battery, let mw know.
I am thinking about to buy a 30Ah version. So as a light back up. The 53 for the holidays and the ligther version for easy handling.

[chris_kline]

lehner 7050 with 5 windings

76mm prop with 70mm pitch, 52mm nozzle

[fabianpusch]

Okay so the motors are more or less the same from their behaviour

[bigbore]

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?

Very beautiful.
Which MGM controller and jet drive are you using?

[fabianpusch]

Hi
It is the MGM 250-63 HBC - industrial version. It is more or less the same like the 400-63 RC version.
The jetpump is a modified 64 MHZ version.
By Fabian

[ropower86]

Hi
It is the MGM 250-63 HBC - industrial version. It is more or less the same like the 400-63 RC version.
The jetpump is a modified 64 MHZ version.
By Fabian

Great job on your board, you have been working on it for long time. I have the jet 64 setup on my jetboard too but the battery pack cannot handle the load so I must go for a powerful battery setup.

[fabianpusch]

Yes, you are right. The battery is the bottleneck.
It is not so easy to find a lightweight solution with a high output.
But at the meantime I am really thinking about to sell all the stuff...my partner is going mad with the first 2 boards hanging around and the actual one which is in our guest room

[fabianpusch]

I also think, that the jetpump could be optimized e.g. more pitch.
Has anyone optimized the MHZ Jet?
I am also trying to build up a pump for 80mm, a target rpm 8000-9000....anyone interested

[ropower86]

I also think, that the jetpump could be optimized e.g. more pitch.
Has anyone optimized the MHZ Jet?
I am also trying to build up a pump for 80mm, a target rpm 8000-9000....anyone interested

You know, mhz is not efficient at all because it needs to run high rpm which causes to many problem and losses. That is why Lampuga went under before it was bought also, those who had jet64 gave up because of the same cause. MGM ESC has a 32 bit system and Flier ESC has a 16Bit system there's a difference. They can work properly when the timing and PWM is tuned correctly. Too many variables to consider however, I came down to conclusion if you buy a mhz jet system you need to spend over $3k/€2.5k then you will see somewhat of a great success if you build the system right. The main issue is heat.. heat.. Heat. Motor gets hot to a certain Celius there is magnetic loss means pulling more current then controller gets hot and if the battery cannot handle the load well you know what is next. The 80mm pump is a great idea at 8000-9000 it will be manageable.

[ropower86]

I forgot to mention, I now have access to the best 3d printers in the world. Did a tour onsite and learned the machine operations to much to digest in learning. They can 3d print in metal too, which the service more expensive. Overall I see a future in production run for jet pump system using this company. May take a visit today.

[fabianpusch]

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 printer in our company.
I have printed the frames for the opening and some other parts, really good and durable stuff...

[FlorianAirs]

Hello,

I will sell my lampuga Air 2016 because i switch to a Jetsurf....

Best Regards:)
https://www.ebay-kleinanzeigen.de/s-anz ... 3-241-2930

[fabianpusch]

Cool, I have seen it already.
Are you buying the defect Jetsurf?

[Bluefang]

FYI anyone have any thoughts on the pumps from the following supplier, they also have a 55mm and 80mm setup. Not so sure about the impellers. I am just hoping there are options to get metal impellers.
https://www.aliexpress.com/item/4000147 ... 72a8NA0K0b

This guys youtube is a riot too, with great info.
https://www.youtube.com/watch?v=6GRExuEdd5A&t=255s

[ropower86]

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 printer in our company.
I have printed the frames for the opening and some other parts, really good and durable stuff...

How does the frames hold up for you and what material did you use? Im thinking about doing the same as of printing out the lid frame and a battery box. That is cool you work where you can use the facility 3d printers.

[ropower86]

FYI anyone have any thoughts on the pumps from the following supplier, they also have a 55mm and 80mm setup. Not so sure about the impellers. I am just hoping there are options to get metal impellers.
https://www.aliexpress.com/item/4000147 ... 72a8NA0K0b

This guy youtube is a riot too, with great info.
https://www.youtube.com/watch?v=6GRExuEdd5A&t=255s

The impeller is CNC aluminum. I have the jet 64, was thinking about the jet 80 but I believe you have to invest more in batteries, stronger BLCD motor, and ESC to handle the output from the jet pump.

[FlorianAirs]

Cool, I have seen it already.
Are you buying the defect Jetsurf?

I have buy a new jetsurf race dfi:)

[pepe pisa]

Hi guys..
by any chance someone has the esc file of the Lampuga boost carbon??
I have completely redone it and I just miss the file to put in the esc to finish it and try it.

I tried to enter all the data by hand but not knowing the engine features and a mess!!

[chris_kline]

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 printer in our company.
I have printed the frames for the opening and some other parts, really good and durable stuff...

hi fabian
what dmls machines do you have? im curious how much it would cost to laser sinter me a 2 stroke engine block/cylinder in aluminium.
p.s. did you try adjusting your motor timing

[fabianpusch]

Hi Chris
To ask for a est. prize I need the building volume...or something like this.
But the metal parts are really expensive. What about CNC?

[chris_kline]

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 dmls tech had gotten quicker and cheaper over the last few years.

ill send some files when i have them, see what the price comes out as, but the idea was to do extremely thin sidewall, which would make dmls more competitive.

thanks

[srn]

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