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Seems like a lot of prop on that setup! Is it getting hot?
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Mini Cat Racing USA
www.minicatracingusa.com -
No, the ESC doesn't get hot, just warm to the touch. It was always cool to the touch with the 215. The motor and batteries never even get warm.Comment
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I know your new.Welcome.This is a fantastic site with many nice and helpfull people.Your rpm is 48,840.With single drives,you should try to keep it around 30,000 rpm.Around meaning you can fudge it up a bit towards 34,000 or somtimes 35,000 with the right prop.If you want a nice cool running 6s set up,try a Leopard 40x82 1500kv.I ran this in my mono and it ran great.This is just my opinion.You will find many more suggestions on what to run...etc.Where did you get your hull?Do you have a link?It looks awesome!!
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Thanks. Here's the link to the ad I bought it from.
This isn't the first I've heard that there is an optimum motor speed that everyone is trying to attain. Can someone explain that to me? My reasoning is that more RPM = faster boat. I also understand that is simplistic, as I'm sure cavitation and excessive drag come into play just like in aircraft propellers.Comment
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Too much rpm here and things burn up.
Voltage x KV=rpm.Comment
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The problem is the higher the rpm, the higher the load. I ran a 1600kv motor on 6s in a catamaran similar in size to your mono and it pulled 209 amps with a prather s225 (smaller than your prop and less load...would pull less amps). The same setup with a s220 pulled around 160-170 amps. You can imagine the difference if I went to a s235...
Now add to that the fact that you are running a 2200kv motor, not a 1600kv motor. I have ran a 1515-1y on 6s before just to see what I could do, and by your video, your rpm doesnt sound as high. Part of the reason is the batteries you are running. Theres no way 6400mah/20C venoms will supply the kind of current that setup should be demanding. Im really surprised you arent hitting the low voltage cuttoff. Are the batteries hot after running? If your batteries are not hot, and your motor/esc is not hot, I would have to beleive either your motor is mis-marked, or something else strange is going on...
Please understand Im not bashing and I realize you're new. Im just trying to help. I did all the same stuff when I was new to FE boating, and its taken me a while to figure out how to go fast without crazy RPM. By the way, the boat looks sweet in the pics and video. I almost bought that boat when spot me 2 listed it last summer. Nice setup
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Maybe he is mistaken by the motor.If you look at the sale thread from spot me 2 I believe he said he had a 1.5y in it.Thats a 1500kv motor I think.Maybe thats whats in it now?Or maybe Im an idiot and cant read-or just have a very bad short term memory.Now,Ill look at the sale thread link again.Comment
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Nevermind.Spot me 2 said the owner before him had the 1.5y in it.Comment
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57burb,look at your can and see if there is still a small white sticker on it.Should state the motor model and date.Tell us what it says.The stickers are normally towards the rear of the can.Sometimes not covered up by the cooling jacket.Comment
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According to the sale post it looks like he has a Neu/Castle 1515 1Y. It also looks like Spot Me 2 had 3s packs in the boat.
I agree with Keith, the video doesn't sound like that motor on 6s voltage, it should be SCREAMING!
Those cells would have to be sagging pretty bad under load. However, that doesn't explain the temps he is reporting unless the run time is VERY short. Perhaps the motor was mis marked.
I'd try to get some more history from Spot Me 2.
DougMODEL BOAT RACER
IMPBA President
District 13 Director 2011- present
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nice boat man and welcome aboard once you start you cant stop. welcome to the addictionComment
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Super nice pics there!
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Those venom lipos are 3s2p packs right? 6 cells in one pack wired parallel to get 11.1 volts. Soo 128 amps total? I'm not surprised that the castle 2200 will take 6s for short periods of time. Nor am I surprised the T-180 will take the load for short periods as well. I am surprised the lipos aren't even getting warm. How long do you run it for at one time? I have the same setup in a cat on 4s and yours definitely sounds like more rpm than mine. Heres what that combo sounds like on 4s......
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Thanks everyone for your comments. I gotta say, it looks like a tight-knit group of friends here.
As for the questions about the boat, I'll take the motor out and verify it's 1515 1Y-ness another time. It's really hard to get out of there.
The batteries are 3s2p and run in series. They have literally NEVER been hot. Run times are 6-8 minutes. The cells are at 4.19 volts after charging, and are at 3.84 volts after a run. Does that sound right?
The low voltage cutoff WAS coming in after about 30 seconds to one minute into the runs. This was with the setting at 3.2, 3.0, and 2.8 volts. I was bringing it back in to charge the batteries after this and realized that the batteries were still showing 4.0+ volts in each cell so I thought it was a faulty ESC. Turning off the voltage cutoff and timing my runs instead has been much more fun. You guys think the batteries are causing me this trouble because they can't handle the peak amp draw from being in a boat?
Let me report one more thing. Switching to the 235 propeller didn't make my batteries run hot, but it DID make my Deans connectors get hot, to the point that one came unsoldered. I was already planning to replace them with bullets, and I have some ideas after seeing the Y-bullet thread on here. The 235 prop did shorten the duration of my runs (from 8 to 6 minutes) but I kind of expected that. You can hear that the motor is under more load.
Again guys, thank you very much for your input. Hope you're having a great Christmas!Comment
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