Project "Nuke the Motor" is about to hit the water..

[NitroVal]

Got all the wiring done, extra plumbing ran, new flexshaft in...


Through-hull pickups (hopefully they work). These are for the motor. I'd rather smoke the motors first if these pickups dont work. The stock cooling system is cooling the Etti's

[Ub Hauled]

keep 'em coming!
wanna se the video when available as well!
:)

[NitroVal]

I'm gonna plop her in the lake tomorrow and see how she does. Only way anyone is seeing video is if she breaks 50mph or explodes...

[Ub Hauled]

are those speaker cables?

[NitroVal]

are those speaker cables?

They are 8awg silver core power cables.. Unfortunately I needed to make the battery leads pretty long because of the cap boards, so I figured these would provided the least resistance..

[NitroVal]

Well, project "Nuke the Motor" was a complete success, kind of. I was able to nuke one of the motors, however there was a ton of chop and wind today and experienced a rough blowover. Was only able to get 41mph out of her, but I would say I barely passed 3/4 throttle. The throttle is very touchy- I put the stock plastic props back on it, and I was doing everything I could to not shear them off, so I was very light on the throttle. However the chop was just horrendous- trying to accelerate in it was impossible. The torque was impressive- she was able to jump out of the water at 30mph with a quick blip of the throttle.
I had some issues with the ESC's, not sure what was going on, but they were very unresponsive from a dead stop to about 1/4 throttle- I usually had to go full throttle to get a response from them. Probably just some Tx or ESC tuning issues. Im thinking my under-hull cooling pickups weren't working to well. The motors were at 160*F by the end of the short runs, while the ESCs and batteries were barely hitting 100*F. The port side motor still spins out of the water, but gives up when any bit of load is applied. Not sure whats going on there, but Im guessing it's smoked..

[Brushless55]

Hmmm only 41 on 5s?

[Ub Hauled]

I agree on the comment of "only 41mph on 5s"... there seems to be a lot of room for improvement.

[Steven Vaccaro]

Good job on getting more water to the motor. But I have to ask, WHY? Why try to burn up the motor or esc's?

[Ub Hauled]

Good job on getting more water to the motor. But I have to ask, WHY? Why try to burn up the motor or esc's?

I asked the same on his other thread...

[NitroVal]

Good job on getting more water to the motor. But I have to ask, WHY? Why try to burn up the motor or esc's?

To help keep you in business...
I really only had intentions to burn the motors up, since I'll be replacing them anyways for something more suitable for 5S. I closely watched the ESC temps and did what I could to preserve them. Neither of the ESCs got over 100*F, so if either of them have failed, it was because of something out of my power..

As for the low speed, if you read my post, you would have seen that the conditions were crap. The boat wouldnt stay in the water due to the wind and high chop.

[Steven Vaccaro]

To help keep you in business...

Ok, thats funny. But I rather make a profit from happy customers, not ones pulling the hair out of their heads.

The problem is that motors run best in certain amp ranges. Increasing the voltage also increases the amperage. Increasing amperage in such a small motor really puts a hurting on its efficiency. Even at partial throttle.

[NitroVal]

WHat would you recommend on 5S with a 442 prop? Or better yet, something to get deep into the 60mph range?

[Steven Vaccaro]

I've never done one, so this is only a guess. In order to use x442 props, you would need about 35k rpm. I rather see someone use a larger prop, say x447 with less rpm. A couple of feigao 540 8xl motors should get you close to 60. One thing to consider is the size of the cable they use. Do you happen to know the size?

[NitroVal]

THe XL's are too big to fit in this hull. I was considering the 11L or possibly the 12L. The flex cables are 4mm

[Brushless55]

My 8XL looked like it would fit in my EKOS ?

[Steven Vaccaro]

THe XL's are too big to fit in this hull. I was c
onsidering the 11L or possibly the 12L. The flex cables are 4mm

So just to double check the flex cable is the same thickness as the prop shafts?

[NitroVal]

Oh, I thought you were talking about the prop shaft part of the cables. The actual bending twisty part thingy of the flex cables are .120"

[Steven Vaccaro]

That will be the weak link. x447's and a big motor will mean shredded flex cables most likely. But thats just theory until its tried. Maybe if your soft on the trigger on takeoff and dont jump waves and have the throttle pinned on reentry they may last.

[NitroVal]

I was actually looking at doing a piano wire swap, but have no idea where to start. The outdrives are meant for a 4mm prop shaft, so I guess I would have to find a wire with a 4mm prop shaft, or possibly drill out the hole to accept a 3/16" shaft??