RC Boatworks Top Gun

[oscarel]

Yeah, I wanted to get a good run in before calling you... I'd hate to get on the water and something else happens.

[oscarel]

Finally got a good run in today. Eagle Tree recorded speed of 65.83!!!!!! This is with 6S2P and CR X452/3's. Amps show one motor pulling 285 amps but I'm not really sure of this number because after 4mins of running packs were at 75% left. So far the .187 shafts are working but I've really had to torque down the collets. Also I lost yet another prop yesterday with one of the nuts coming off, so now they're loctited down good. Running CR 457's I had top speed of 59 with amps showing 305. I think for regular running I'm going to only run 5S2P since 65 is way too much for now...

[Fluid]

Great speed, that is right in line with the motors and props you are using. The amp draw is more problematic. If you really ran for 4 minutes and only used 2500 mAh then your average amp draw was under 40 amps. Something isn't right here unless you were off the throttle a lot more than you were on it. I assume the 285 amp reading was a peak reading? Those motors won't pull that kind of amperage running 65 mph.

And what prop nuts are you using? You should never need to use Locktite on a prop nut! Good staked nuts like Zuber nuts will last a long time and you won't lose a prop. Some cheap staked nuts (from China???) are loose and will back off.


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[txboatpilot]

Good new! We will be at the pond around 10am tomarrow,, hope you make it out with this bad boy!!

[oscarel]

Great speed, that is right in line with the motors and props you are using. The amp draw is more problematic. If you really ran for 4 minutes and only used 2500 mAh then your average amp draw was under 40 amps. Something isn't right here unless you were off the throttle a lot more than you were on it. I assume the 285 amp reading was a peak reading? Those motors won't pull that kind of amperage running 65 mph.

And what prop nuts are you using? You should never need to use Locktite on a prop nut! Good staked nuts like Zuber nuts will last a long time and you won't lose a prop. Some cheap staked nuts (from China???) are loose and will back off.


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I'll post the eagle tree data later today, it was late and I with the time changing I ran out of time. It was 4 1min runs since I'm down one cooler so they were SAW type runs. The prop nuts are ose-8135, there are a few things that normally wouldn't have been done, but to save losing parts I've had to do. At this point I'm just estatic I was able to get a few mins of run time without spending any more money.

[oscarel]

Good new! We will be at the pond around 10am tomarrow,, hope you make it out with this bad boy!!

I'd love to but there's too many people off this weekend. I'm going to see if I can schedule next month off.

[oscarel]

Here's the eagle tree data , I have it stop when full so I didn't get the last few runs. So just to show the eagle tree is off it shows 3400 mah used and I just completed charging the lipos and I put in 2800 with balancing. I'll get video later in the week.

[Fluid]

Your average amps is closer to 130-140 which is more like it. The 295 was a maximum, but all those max values seem on the high side to me. You would not expect to have the mAh from the Eagle Tree match the charger value exactly - but that is a ways off.



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[Brushless55]

Your average amps is closer to 130-140 which is more like it. The 295 was a maximum, but all those max values seem on the high side to me. You would not expect to have the mAh from the Eagle Tree match the charger value exactly - but that is a ways off.



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2800mah burnt in 4min is more like 40-45 cont.

[oscarel]

So if I highlight the first 55 secs it shows avg 93 so X2 would be, if this thing is reading correct, 180 amps average.

[Fluid]

2800mah burnt in 4min is more like 40-45 cont.

Read post #33 buddy, then read the graph. We want to know what the combo pulls, not how including how much time he spent off-throttle. That's why we use data loggers, otherwise all we'd need is a stopwatch and a charger. His average on-throttle draw is about right for the boat and speed, perhaps slightly on the high side. The spikes are quite high but may be okay considering the size and weight of the boat to get on plane.

So if I highlight the first 55 secs it shows avg 93 so X2 would be, if this thing is reading correct, 180 amps average.

No, I was looking at the amp curves. You were on and off so much you can't really use the program's "average" function. With my Castle ICE controllers I download their data into an Excel program and find best-fit curves graphically. Here I had to eye-ball it.





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[Brushless55]

Read post #33 buckwheat, then read the graph. We want to know what the combo pulls, not how including how much time he spent off-throttle. That's why we use data loggers, otherwise all we'd need is a stopwatch and a charger. His average on-throttle draw is about right for the boat and speed, perhaps slightly on the high side. The spikes are quite high but may be okay considering the size and weight of the boat to get on plane.


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Ok buckweed

[Fluid]

Ah well, yet another rocket scientist for the ignore list.



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[Brushless55]

Ah well, yet another rocket scientist for the ignore list.



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[oscarel]

I was able to get in another quickie today, this time in a bigger part of the pond and without on/off the throttle as much. The amps this time are from the other motor and they are running about the same. I was able to pick up a couple more mph, 67.9. I had my youngest attempt to video, but she got more sky and shoreline than the boat.