Electric Surf Board

Boats, Jet Skis, Kayaks etc., including hovercrafts
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Infinity   10 mW

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Re: Electric Surf Board

Post by Infinity » Jun 28 2014 2:41am

It seems like watewolf is using torqeedo props. Compare these two prop pics: 1. Is torqeedo original, 2. Is from waterwolf home page: http://cdn-products.austinkayak.com/p_1634_700.jpg
http://www.waterwolf.de/products.html

The props look exactly the same to me...:D. Maybe the prop was just painted yellow in the video!?
They are using reduction gearing and high battery voltage. That seems to be the most efficent way to make this thing go fast without extreeme heat.

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jun 28 2014 5:24am

Image

This something that I have for a while, it is one of the bigger trolling motors, I just smashed out the magnets from the brushed motor, but to avoid eddy currents I have a exact copy make of nylon/plastic or something. With watersealings etc, so this is waterproof.

The shaft is machiend for this, so it will fit in the bearing through the 45 rpm/volt Turnigy motor, through the watersealing of the housing, than a wider diameter so it will fit many boat props.

But I still go for the under water drive, I just plasti dipped the stator, so it has an extra coating around the windings.

http://continuouswave.com/cgi-bin/propcalc.pl

If I run 12s Lipo at 44v at 45kv turnigy = 1980 rpm at 12 inch torqeedo prop with 10% Slip I should be able to go about 32 km/h.


Sounds easy, now I hope this will work in real life. I hope the 18 Fet sensorless motor can handle this.

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jun 28 2014 5:42am

http://www.emarineinc.com/categories/El ... edo-Parts/

Many props out there, is it just 10 " pitch and 12 "pitch what they call high speed prop ?

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Tommy L   100 kW

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Re: Electric Surf Board

Post by Tommy L » Jun 28 2014 5:51am

nessan1one wrote:Battery...
http://www.ebay.com/itm/Rechargeable-Ba ... 338d6fce0e


I'm not sure that this pack would last long and may have a quick death. It is a 2C max and 0.5C constant.
960 watts burst and 240 watts constant. Size for longevity ;)


Tommy L sends.....
http://www.rawvelocity.com

- 4th Hoolagan FS Mtn 9C-2810 with 128v nom 9.2ah A123 40S40P(1.2Kw) - Lyen 18Fet 4115 - 77.8kph :)
http://endless-sphere.com/forums/viewto ... =4&t=39480

- 3rd Catrike 700 Bionx PL350 Velo build
http://www.youtube.com/watch?v=rYdnkaAhVtI

- 2nd 150lbs Pusher Trailer
http://www.youtube.com/watch?v=Q1qTc4sjORY

- 1st Sears NS mtn bike - Rigid 10a drill 800rpm - 2 12v AGM - 1000 watt inverter - 600w dimmer for throttle, wicked torque!

48.2mph/77.8kph Club

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Infinity   10 mW

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Re: Electric Surf Board

Post by Infinity » Jun 28 2014 6:11am

Bazaki wrote:http://www.emarineinc.com/categories/El ... edo-Parts/

Many props out there, is it just 10 " pitch and 12 "pitch what they call high speed prop ?
http://www.emarineinc.com/products/Torq ... p4000.html This one is for high speed!

The marking of torqueedo props means: (v = speed in km/h at p = power in watts)
Torqeedo suggest to use that prop with light boats, because it can cause the stock torqeedo motors to overheat

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jun 28 2014 9:21am

Thank you, but can't we see somewhere the pitch for each model ? Because the normal prop is 79 usd and this high speed prop is 219 usd.

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Infinity   10 mW

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Re: Electric Surf Board

Post by Infinity » Jun 28 2014 9:50am

I Dont know about pitch, but the high speed one is 2cm bigger in diameter than other props! Then there is the second fastest (it is quite new as I haven't seen that before): http://www.emarineinc.com/products/Torq ... p4000.html

^This should be faster than the stock v8/p350
I got some more info about the stock prop, it is 12 in. x 10 in. variable-pitch-variable-camber (VPVC) propeller.

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jun 30 2014 3:31am

http://www.torqeedo.com/us/electric-out ... dimensions

So max 1300 rpm, then how can a boat goes 30 kmh with 12 inch pitch ?

Louis

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Infinity   10 mW

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Re: Electric Surf Board

Post by Infinity » Jun 30 2014 4:10am

v8/p850 has 10 inch pitch, v19/p4000 has 12 inch pitch. I don't know the high speed (v30/p4000) pitch.

but with the v19/p4000 at 1300rpm you should be going 23.77 km/h (without any losses)

12 inch = 0.3048m

0.3048m x 1300rpm /60s = 6.604 m/s = 23.77 km/h

And here you can see that max speed with twin torqeedo 4.0 and the high speed prop is 816.1mph) 26 km/h
http://www.torqeedo.com/us/electric-out ... e-run-time

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jun 30 2014 8:37am

Hmm ok.

I just coated the stator and windings with plastidip and removed it from the stator again, but now I think, that might going to rust, so I probably better can spray new plastidip to the stator, there will be layer of plastidip and I wonder if that can hurt the performance beacuse of the layer inside the magnetic field. Any thoughts ?

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Infinity   10 mW

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Re: Electric Surf Board

Post by Infinity » Jun 30 2014 11:54am

I don't think that you will lose any performance, bec the layer is so thin. You have to make sure that the plastidip won't cause any contact and excess friction between the parts, then it will be OK.

If you want extreme waterproofing spray then try this: https://www.sprayon.com/products/clear_ ... ng_varnish
You can google it, it is quite cheap and they have different colors too.

Or this: http://www.crc.co.nz/Automotive-Corrosi ... c-6552.htm
This even protects form salt!

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jul 01 2014 1:53am

Thanks, I will look into that.

I now have both props, the one that is stock on a Torqeedo 2.0r and the high speed prop 12x12.

The high speed 12x12 is a big prop and also the material is much different. Both props are from a neighbor, I can use them for a while.

The High speed prop was about 350 euro and there is a high risk of damaging it, so I go for the cheaper one.

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Infinity   10 mW

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Re: Electric Surf Board

Post by Infinity » Jul 01 2014 2:09am

So you are going to test both?

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jul 01 2014 10:14am

Turnigy shaft is 12mm, torqeedo is 10mm. So or I need a new shaft, or I will make the torqeedo prop 12mm. But I can't drill holes in my neighbors prop. So I probably just order 10 inch prop.

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jul 04 2014 11:56am

I have the 45 kv Turnigy running under water, work great till about 60v. Or about 2700 rpm. After this voltage/rpm the rpm will drop and current will stay the same, maybe it are the wires that attach the windings that maybe have contact with water ? Too bad, I wanted to play with much higher rpm's. Above water it can run 3400 rpm at 75v without problems.

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Re: Electric Surf Board

Post by blisspacket » Jul 14 2014 7:00am

FYI
http://www.simplicity-marine.com/surfprop.htm
Adopting this setup would require seals, etc, but it gets rid of much underwater drag. Rudders likewise can be omitted if two surface drives are used.

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jul 15 2014 2:58am

Yesterday I tested my 45kv c80-100 at 44v with 11 inch boat prop under my surfboard. It dit not work well and I don't know why.

The motor is spinning 2000 RPM above water, the motor also spins under water with 2000 rpm without prop, but with boat prop it can run about 300 rpm and than it looses sync or something else happens.

So with prop there is resistance and it looks and sounds like it is out of sync, but is it possible that if the windings are not 100% isolated with coating that current is flowing through the water and there is some "short circuit "through the water ? Without prop there is no load and is taking about 3A and there are no problems but with prop it takes about 20A and therefore the water will make a short circuit ???

What else could this be ?

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Re: Electric Surf Board

Post by blisspacket » Jul 16 2014 4:46pm

I had a bright U of Fl student point out to me that surrounding an outrunner motor with aluminum is a no-no. I don't know if yours might be set up that way. There are magnetic influences within the outrunner which get messed up when contained within aluminum. The practical test to illustrate this: drop a neodymium magnet through an aluminum tube. You'll observe that there seems to be less gravity within the tube, and the magnet drops markedly slower than just letting it go in free air. :?:

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jul 16 2014 11:14pm

I know about the Eddy current. Thanks.

My motor is running IN the water, so no housing at all.

Originally the Turnigy motor has a retaining clip at the shaft, I did not install this. And the outrunner is going off the stator a bit when there is a pushing force from the boat prop, and the magnets are a bit of the stator, maybe this is the problem when powering under water with prop.

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Re: Electric Surf Board

Post by blisspacket » Jul 17 2014 1:28pm

I'm suffering the same motor symptoms. Out of the water gets 3000 to 3400 rpm (should be more on a 48v 170kv 6374). In the water it spends fewer and fewer seconds spinning nicely, then goes to an out of sync mode. Last immersion was only about 2 minutes before I lost sync. I can regain operation after a time period by plug in the self instruct connection on the controller and sometimes it gets going, runs quietly.

But immediately a light load--1400 rpm on the prop in the water--it goes out of whack.

Everything points to the chinese controller, a 2000 watt unit, 24 mosfets, KevinGu is the person who answeres correspondence. What controller are you using?

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Jul 18 2014 4:42pm

So you are also having these problems..... Today I tried other things that did not work, finally I found out that all phase wires had contact with the water, just have your ohm meter at the water and the phasewire.

So I plasti dipped the stator and windings even more but the skirt bearing is very close to the windings so it was hard to cover everything. I did a new attempt and had the same problems, but I also found out that even after the pasti dip the fase wires are still in contact with water.

So I now even more plasti dipped it and let's see what happens tomorow.

I hope it is the water contant problem, if not, I am afraid of some kind of eddy currents or other magnetic field that is in the motor because of the water, and that would not be solvable

I use 44v aa 18 fet eb03 controller, sensorless.

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Re: Electric Surf Board

Post by dirkdiggler » Aug 02 2014 12:56am

Finally tried out the Torqeedo prop. Didn't last long due to the motor being losing sync. I tried the motor in the tub for a about fifteen minutes and didn't have any issues. That was without the prop. I guess with the extra weight on the motor in the water it is too much for them. Seems the next option is to get it waterproofed. I'm hoping to test it out using a plastic jar that will at least keep it dry long enough to get a ride. Hope to get this going finally. Aquilla might just be the better option!

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Aug 02 2014 2:13am

I wonder why it goes out of sync, I never ran this motor with load on a bike or something. So maybe it is not the water that is causing the out of sync problems. Maybe the combination of motor and controller is going out of sync anyway with load ?

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Re: Electric Surf Board

Post by dirkdiggler » Aug 02 2014 11:59am

It has to be the water with a loaded motor. Everything ran fine out the the water. The minute it was submerged it lost sync. The weird thing to me is that without the prop submerged it ran perfectly. The other prop made it lose sync after a while, but not nearly as badly as with the bigger torqeedo. I hope to get it enclosed and tested by next week. This has taken much longer thanI eexpected.

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Bazaki   10 kW

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Re: Electric Surf Board

Post by Bazaki » Aug 02 2014 3:32pm

Whats the next step? Better water proof? If yes, with epoxy? I have exactly the same problems. I hope it is not the water between magnets and stator.

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