55" Quad or Triple Cigarette Boat

[Jacked1]

This thing is coming along real nicely! its going to have a whole bunch of power to it when your done!

Thanks! It will have a possible 13kw at max. I think it will be uncontrolable if I actually use all the power tho.

If nothing frys from a defect esc's or motors I think running very cool at 65mph is pretty attainable. I am guessing I would need about 9kw or a little less to hit 65 which would be about 100amps per motor/esc which should be easy for both.

I have a small row boat and I was joking with my friend that I could possibly tow the row boat with this thing to retrieve other boats!

[Boaterguy]

I was going to do this with my boat, but I don't think it would be structurally stong enough, put a post on it and get someone water skiing behind it.

[d3lap]

Could a wooden hulled boat withstand 40+mph speeds?

[Boaterguy]

ask simon O, his balsa rigger went over 40 if i'm correct.

[Rumdog]

You must have never seen a Whiplash hydro..

Anyway... how long till this project fires up for a bench test?

[Jacked1]

Haha I know a guy who built his own twin wooden nitro rigger (including machining the motor, might be the nicest boat I have ever seen) that runs at the Dayton rc boat club and I think he said it is pretty close to 100mph.

I tested each motor individually last night before I put the big unit in there and programed the ESCs. I am going to see if i can't get some milk jugs with ice water in them and gravity feed them trough everything and run it for 5 mins to make sure everything is okay, Either tonight or tomorrow. I will try to get some video of it asw well.
And the ETA to the lake would be friday at the earliest (Hopefully!) and if not, Monday or Tuesday because I am going to be away for the weekend to ride me some rollercoasters with my lady!

[Jacked1]

I am filling up the esc box with oil and it is pretty rediculous how long it takes for this stuff to flow through the tubing if all that is making it flow is gravity through a syphon!

[Jacked1]

All motor test on 3s complete!!!!!! Everything was flawless and THIS THING SOUNDS AWESOME!!!!!!! I videoed a little bit of it! Uploading now!
Box and motors were all cool afterwards!

[Jacked1]

VIDEO!!!!!

http://forums.offshoreelectrics.com/...729#post344729

BANG!!!!

[d3lap]

Omg that sounds amazing.

[Boaterguy]

I bet it sounds even better in person! 13kW will put out alot of heat!

[Jacked1]

Oh yea the vid does no justice to the sound! I probobly won't run it at 13kw very much if any so the boat will last a long time.
I will have a ton of water flowing through everything and it will take 16.7 kilojoules to heat the oil up 10*C.

[Boaterguy]

How does the water cool the oil? does it just sit on top?
and 16 kJ is a fair amount of energy! do you know how much heat the ESC's will be putting out?

[Jacked1]

I have two 12 inch long brass tubes that run through the esc box, you can see them if you look close. They are touching the aluminum on the bottom and are also submerged in the oil so no water will get in. I figure if the esc's are each 95% efficient they will dissipate a total of 500 watts at 10k watts. So that is roughly 35 seconds of full power the oil can hold alone. And that doubles if you change 20*C instead. Also the esc cooling fans will be blowing on the aluminum on the bottom of the box. :D

[Boaterguy]

so the temp gain is with or without the water cooling? I guess it doesn't matter because you already have some good cooling. I'm assuming you are using a 1/4" flex?