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What really grinds my gears.

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Old 08-03-2012, 01:26 AM
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Default What really grinds my gears.

1 Is RC universe new? Seems this forum is dead compared to RCgroups.com2 The price of things. I'm 23 with a newborn and the army pay is two thumbs down. Someone please tell me the cheapest place to get a lipo setup for maybe a 100 amp system before I go brushless.3 What's the difference between buying eBay items from Asia and from some company who gets there stuff from Asia. I can care less about customer service. And most powersellers do returns and either way your going to pay shipping so why let some company rip me off just for the name???
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Old 08-03-2012, 09:36 AM
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Default RE: What really grinds my gears.

Hobbyking.com

Capacity (mah) x C rating = max amp draw
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Old 08-03-2012, 07:21 PM
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Default RE: What really grinds my gears.

Is that really the rule of thumb?! So a 70c 6500 mah lipo can handle 455 amps discharge for an esc?! Sounds extreme you don't think there's more to the formula?! I understand 70c is a pretty high rating but figured there was more than that. And that's it only one reply???? This forums asleep....
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Old 08-03-2012, 07:44 PM
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Default RE: What really grinds my gears.

zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz...oh wait, I woke up. Coming here with an attitude isn't going to get you much help - it may be difficult to understand but that kind of thing offends a lot of folks. BTW this particular forum is quite OLD - 2003. RC Universe began prior to 2002.

Yes, the formula is really that simple - mAh x "C" = maximum continuous amp draw

BUT there are always buts. If you want your packs to last then don't exceed 80% of that maximum. So for a 40C/5000 mAh pack that's a maximum of 160 amps.

BUT with cheap packs the stated mAh and "C" ratings are probably inflated, so the formula doesn't work. One of the things you pay for with higher end packs is real performance numbers, or at least numbers closer to the truth. We went through all this with round cells a decade ago - cheap packs with fantasy performance numbers.

Virtually all LiPos come from Asia, but not all come from the same factory. And even cells from the same factory are not all the same. In any production lot there is a variety of performance values, some cells are very very good, some are very poor. The factory does not throw anything out, they sell the lousy cells to the sellers who sell cheap packs and the high performance cells to the sellers to provide premium packs. All very normal and natural, this is one reason the cheap packs are cheap - they may be sh*t but some consumers don't care, all they want is the low price. Unfortunately they often end up without their money and without cells which work...not much value there. If all the cells a "power seller" sells are sh*t it will do you no good to get returns......



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Old 08-03-2012, 07:55 PM
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Default RE: What really grinds my gears.

Yes its the rule of thumb if we are only talking batteries.
So a 65/130 C 5000mAh Lipo is capable of giving 65C Constant (325Amps) and 130C Burst (650Amps) if your setup is capable of pulling that much.

If your ESC/motor combo can pull a maximum of 140 Amps, than that battery is not going to give your setup 325Amps.
You want a setup that will give you 100 Amps of power, get an ESC that is a bit bigger to have a safe buffer zone and a motor that can handle it and than choose your battery to match your setup.
You can buy from anyone you want, that is your choice.

Hobby King is a great place to shop, not everything is A1, but they do have a lot of great stuff that work has good if not better than most over priced items.

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Old 08-03-2012, 09:23 PM
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Default RE: What really grinds my gears.

You shouldn't be offended unless your the one selling the bull ish. And besides saying that this forum is dead is true. It doesn't mean that people are idiots it means they have better things to do and I hold no hard feelings. I mean some Guy made fun of my boat on here but I didn't cuss him out or tell him to get lost my boats awesome to me and spending 60-70 bucks to build it is fine with me cause it works. But on the flipside thanks guys seems everyone's input on lipos is to try hobby king first which I will be. Anyone reccomend a cheap charger? I know they have one for 10 or so bucks but lipos seem a little to precious to throw on a cheap charger unless anyone can speak on there behalf. And is there any American made esc's out there?!
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Old 08-04-2012, 12:28 AM
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Default RE: What really grinds my gears.

It took 8hts for the first response- in in the uk.
Is that slow? Actually a web search would have given the answer quicker I guess.

Hobbyking Di several chargers- spend as much as you can on one. If you have large batteries you will need large watt charger.

Most 5amp 50 or 80w chargers do not need POWs supply.

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