Epr 5000

[pda75]

Hi

I have started a new rigger and here are some picture of the build.

It a 1,28 meter (~50 inch) long rigger about 16 lbz. It will be powered with a lehner 3040/12 (875 kv) with lipo 10S2P. ESC is an YGE200 Navy.

EPR 5000 means in french "nuclear plant 5000" and in english "Electric Propulsion Rigger 5000 watt"

the boat is design for oval racing with 90 nitro riggers.

CDG is of course a real question. The implementation in the following:


2 lipos in front, the motor and 2 lipos in the back. The weight on the strut could be in a range of 700 gr to 1,2 kg (eg 0,9 lbz to 2,1 lbz).

My calculation based on rpm and propeller size (likely to be an octura X460) is that the right position of the CDG is obtained with a weight of 1,5 lbz on the strut.

The flex wire is about 60 cm long: Rember the the motor can move backward and forward in order to cope with flex wire length reduction. I hope that it will work well and that the flex will not blow up.



Feel free to help me as I have not found many similar projects

regards

Pierre

[pda75]

Here is the engine : it can move forward and backward in order to avoid flex cable reduction

[pda75]

For fun, the sponson compared to mono 2 (70 cm ~ 27 inch) electric boat

[pda75]

Water proofing of the hull is ok.

My assistant is checking that no water is coming !

[pda75]

the painting

[pda75]

the boat first run was this summer. Speed is fine. it runs about 110 - 120 km/h (eg 70 - 75 mph).

Some video :

http://www.youtube.com/watch?v=C32EwV5K4a0&feature=related

http://www.youtube.com/user/scyllias91#p/a/u/2/C32EwV5K4a0

The elogger (from eagle tree) is not working in this hull. it's to close from the motor and RFI from the motor reset the logger : I need to change all the wires.

I will also make some changes to put more weight on the strut in order to use bigger prop and hopefully go faster. Weight on the strut is currently about 1,1 kg (39 oz) and I need 1,4 (45 oz).

I am now starting the winter work :

1-new transmission with teflon instead of brass tube and oil. (too much noise and vibration)
2-More weight on the strut
3-improving the e-logger (eagle tree) system.

regards

Pierre

[carlcisneros]

Pierre:

what is the angle on the strut?
It looks like it has too much angle,

Carl

[pda75]

Carl,

I have tried various angles. Even with zero, the strut is "bumping" like on one of the video.

Pierre

[carlcisneros]

what prop are you running?

Carl

[pda75]

Hi

I have tried a couple : X460; X560; Y557, V955, 1657 and 1457. So far the X4 xx et Y5xx series working well.

The 14xx, 16xx provide too much lift (or I need to put more weight on the strut - that's the winter work)

I should get some propshop prop soon.

Regards

Pierre

[carlcisneros]

good choices on props.
what you can do for adding weight to the back end, is get a 2 to 4 ounce (up to 250ml)
fuel tank and put it in the back of the boat and add water to it until the back end settles down to your liking THEN put that amount of actual weight back there.

Carl

[pda75]

good choices on props.
what you can do for adding weight to the back end, is get a 2 to 4 ounce (up to 250ml)
fuel tank and put it in the back of the boat and add water to it until the back end settles down to your liking THEN put that amount of actual weight back there.

Carl

We had the same idea.
I did it and came to the conclusion that I need about 150 gr more.

I will have to make some changes (nexw antena mount, new servo moint, some pieces of carbon to remove etc... ) in order to push backward the lipos pack and stop running with a water tank on the back. : that's the winter work.

Pierre

[karolpenconek]

Hello. Really nice hydro Did you buy it or make it yourself?

Thanks Karol, Poland

[pda75]

It is home made : We are three friends working on it : one for the hull, one for the painting and myself to coordinate and assembly.

Pierre

[pda75]

A new motor mount




Regards

Pierre