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Old 08-17-2007, 12:33 AM   #41
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Originally Posted by wrecker View Post
So would a 10c 1100mah 3s Polyquest battery be good for a comp sw3?
I'm running a mamba 25, bm9, 12t pinion, 86t spur, xx tranny.
I'm trying to make it as light as possible and help on start ups. Sometimes right now it won't start up if I'm on a really steep climb if I've started rolling backwards. This is the biggest thing I'm trying to fix since nats are coming up. Is the 10c not enough? It's one of the batts Cheapbatterypacks.com has on sale.
I have one of those in my flat out stunt plane, not near enough balls to pull a mamba 25 and a bl motor.
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Old 08-17-2007, 07:32 AM   #42
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Originally Posted by RXcrawler View Post
They still exploded but it wasn't the batteries fault.
It don't matter!
I love my family too much, to risk a house/car fire, over some RC batteries...

Just my .02
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Old 08-17-2007, 07:49 AM   #43
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Quote:
Originally Posted by Kamikaze View Post
I have one of those in my flat out stunt plane, not near enough balls to pull a mamba 25 and a bl motor.
Thanks, that's what I needed to know.

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Originally Posted by johnrobholmes View Post
Thats really tiny. That only gives you 10 amps continuous. If you were to stall out your motor for any period of time you would probably flatline the battery and hit the voltage cutoff.

I would recommend a 1300 15C battery at the smallest.

Thanks JRH. I guess that battery would defeat the purpose of me switching to lipo in the first place then. I wan't to get rid of the stalling and not starting up!
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Old 08-17-2007, 08:00 AM   #44
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Originally Posted by raytard View Post
It don't matter!
I love my family too much, to risk a house/car fire, over some RC batteries...

Just my .02

Appeartly you have never dead shorted a NiMh. Not quite the same fireworks show, but plenty of juice to start a fire. I almost set the bed on fire at the West Coast Championships.
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Old 08-17-2007, 08:20 AM   #45
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Apparently you have never dead shorted a NiMh. Not quite the same fireworks show, but plenty of juice to start a fire.
Yeah,
The first time I made a battery pack; I shorted two batts through the side of the cans...

Still;
It doesn't have the same "explosive" power!!!
A lipo would have burnt your room to smithereens!
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Old 08-17-2007, 08:52 AM   #46
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He later found out that the charger was the problem not the battery. They still exploded but it wasn't the batteries fault.
All NIMH and LIPO fires are Human Error.

Hope your cell phone don't catch your ear on fire!!
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Old 08-26-2007, 09:44 PM   #47
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Originally Posted by Kamikaze View Post
I have one of those in my flat out stunt plane, not near enough balls to pull a mamba 25 and a bl motor.
I have to admit I was wrong on this one, I just put a bm-9 with a mamba 25 in an axial scorpion, I used this battery just to se what it did, it did surprizingly well, got a little warm but the motor ran strong and hot and the mamba got good and hot to, the battery worked good. More testing will tell but for $15 you can try it. Works ok in the scorpion, but the whole truck is very light, 4 to 5 lbs rtr.
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Old 08-26-2007, 09:46 PM   #48
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Take a look at A123's instead of LiPo's.
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Old 08-26-2007, 09:48 PM   #49
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Yeah man, a BM9 and Mamba in this light truck works really good. A 2 cell 1320 TP is nice, I can only wonder what a 3 cell is like.
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Old 08-27-2007, 09:01 AM   #50
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Ok folks, I picked up a lipo (3s 2100) and a balancing charger to give this stuff a try. I'm still being more than a little paranoid about these packs (probably a good thing, really) but one thing has me concerned. I set my Mamba Max to auto lipo cutoff. When I turn it on, it seems to beep three times, then if all goes well, go into regular operation mode. Sometimes that's not the case though. Sometimes it never goes into operation mode - which is a problem I didn't have before I set it to the auto cutoff. Previously with NiMH cells, I didn't use any shutoff at all. Is this normal?

Next question. The ESC goes into operation mode. I drive the truck around. When the voltage gets low, rather than cut off, the ESC seems to start glitching - it acts like it thinks it should cut off, but it doesn't, it sits there and twitches. Is that normal? If this is the expected behavior ...fine. If it's not, I'd like to know if anyone has any recommendations on how to handle/resolve this.
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Old 08-27-2007, 09:32 AM   #51
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Do you have the latest version of the firmware, I believe there was a problem with the auto lipo cutoff that they fixed.
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Old 08-27-2007, 09:57 AM   #52
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Just set it to the 3S cutoff, sounds like thats the only LiPo you'll be running through the MM anyway. Unless you plan on running LiPo's of various S counts.
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Old 08-27-2007, 10:17 AM   #53
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I thought about that - it really only presents a problem if I throw a single 7.2 nimh pack in there to bash with. Maybe it's just time to bite that bullet though. As far as the firmware, I honestly don't know what version it's running, mostly because I don't have a windows PC to plug it into - looks like I'll borrow the wife's laptop though and see whats up.
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Old 08-27-2007, 11:08 AM   #54
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http://www.castlecreations.com/downl...mamba_max.html
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Old 09-04-2007, 03:57 PM   #55
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Since this thread got sticked as a good source of LiPo information, I thought I'd come back and ask this here. A guy at work today, who I didn't even know was into R/C came up to me and asked me what, if any, advantages there were to LiPo other than the power to weight. That seems to be the only positive you hear about, and then everyone hypes them blowing up, or some other nonsense. Anyone got a definative list of pros and cons on these? I told him I'm sure there are more pros than just power to weight, but that I'd try to find out more for him.
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Old 09-04-2007, 03:58 PM   #56
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The discharge rate is pretty even until it is dead. NiMh slowly drops off until the end. So you get the full punch throughout with LiPo vs NiMh.
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Old 09-04-2007, 04:01 PM   #57
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Practically non existent self discharge.
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Old 09-04-2007, 04:06 PM   #58
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Originally Posted by cotharyus View Post
and then everyone hypes them blowing up, or some other nonsense.
Nonsense AZZ


If you would have bothered to come to the last comp() you'd have the noise in your ears, anytime you wanted...
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Old 09-04-2007, 04:10 PM   #59
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Quote:
Originally Posted by Cloak View Post
The discharge rate is pretty even until it is dead. NiMh slowly drops off until the end. So you get the full punch throughout with LiPo vs NiMh.
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Practically non existent self discharge.


These are the two biggies. There isn't any noticeable drop in wheelspeed until the last 5% of the pack, as long as the pack is right for the job. If stored at 3.6v and 70*f they will self discharge over the course of about 5% per month.
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Old 09-04-2007, 04:46 PM   #60
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Quote:
Originally Posted by wrecker View Post
So would a 10c 1100mah 3s Polyquest battery be good for a comp sw3?
I ran that batt at the Axial comp in my SW3, and it worked fine, but I agree with JRH, if you were to stall the motor hard, it would hit the cutoff. I don't stall my motors, always let off instead of trying to push through the stall, so I haven't had any issues yet.
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