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Old 11-28-2008, 12:56 AM   #16
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All you need is a GFX and a Novak SE Smart Tray to maintain packs. That is what I use.
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Old 11-28-2008, 08:20 AM   #17
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As long as you keep the charge rate withing reason, you will have no problems. Don't charge at 8A or 10A, it isn't worth it. The only cell explosion I have seen was from a pack getting shorted out on a metal object and discharging at an extreme rate. I have been in the hobby for 20 years and have owned dozens of battery packs and have never had a problem with exploding cells.
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Old 11-28-2008, 08:47 AM   #18
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Quote:
Originally Posted by Cheezburger View Post
Hmm... so what's a good typical charger / equipment i would need to maintain these batteries properly?
Typical? Diversity is typical in RC :-)

I've got a couple Dynamite Prophet Plus chargers that would be fine for anyone starting out. You can find them dirt-cheap on eBay. Maintain properly? That's another story. To maintain batteries, don't get Stick Packs - get flat packs like this -

You can get a good number of runs by not maintaining packs "like the pros" however. You can charge, race, cool and re-charge without too much trouble. Thing is you may want to get more advanced as you progress in electric-RC by buying balancing trays and DVM (Digital Volt Meter) to check each cell. You can also charge individual cells in a flat-pack by using allegator clips but it's preferred to just discharge sets of cells in a discharge tray (a Trinity Absolutezero is what I have). When maintaining packs like that, you can find out if you have a cell going bad and know which you could replace - cheaper to replace a single cell than a whole pack.

Check out www.cheapbatterypacks.com - they have a 5000mAh cell (Elite) which is at a good price point for large capacity and power - and a good cell to start with for 1/10th scale racing. You can then go get matched packs once you are in the A-mains and doing laptimes closer to the leaders. By that time, you'll probably be moved to LiPo anyway.

But others are right - if you have zero chargers and packs now - you may want to just go LiPo out of the box. A couple *good* LiPo packs and charger wouldn't be more than say $200-250 total. And, you can skimp a little and get a charger like an IMax B6 which supports LiPo with a built-in balancer and a couple mid-range LiPos for under $200 total and you'd be benefitting from the ligher weight and added "punch" of LiPos right away.
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Old 11-28-2008, 09:38 AM   #19
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if only there was internet back in the 80s when all of us old timers dealt with advent of nickel cadium technology.

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Old 11-28-2008, 09:57 AM   #20
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IB are not the only nimh cells that have had issues, other cheap brands like Venom and Tenergy have as well. That being said in the majority of the incidents user error was likely the culprit. You dont have to buy the absolute best packs but avoid the bargain bin type stuff and buy quality, take care of it, and charge properly and you will be fine.
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Old 11-28-2008, 11:55 AM   #21
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Thank you for all your support guys really. What i'm planning to do is get the Traxxas Slash, Pro-match 4600mah 7-cell pack. Still not sure about the charger. I considered starting out with LiPo, but with the slash i would need to get the VXL system as well. The bill would come out to over $500 which is pretty hefty. That's why i'm planning to get a charger that can work with LiPo as well so i don't have to buy a 2nd charger and waste money. Now here's what i'm thinking... Is it possible to get a charger with no discharge / balancing features, then use a discharge/balancing tray to compensate?
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Old 11-28-2008, 12:04 PM   #22
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the slash will accept lipos with out any mods at all. the stock speedo will handle up to 3 cells lipo with no issue at all.
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Old 11-28-2008, 12:25 PM   #23
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[QUOTE=ultegrasti;5103169]if only there was internet back in the 80s when all of us old timers dealt with advent of nickel cadium technology.

yea....i hated to try and make 4 min. running mod on a 1200 scr pack. thank god the 1700 sce came out...lol
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Old 11-28-2008, 01:16 PM   #24
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[QUOTE=frankiecmgt;5103562]
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Originally Posted by ultegrasti View Post
if only there was internet back in the 80s when all of us old timers dealt with advent of nickel cadium technology.

yea....i hated to try and make 4 min. running mod on a 1200 scr pack. thank god the 1700 sce came out...lol

People thought I was crazy running a 15Tdouble for mod buggy back then....way too much motor for a car.....
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Old 11-28-2008, 01:21 PM   #25
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If you plan on racing it, check with the track - if you run stock slash or "spec" find out how many cells they want to have you use - whether 6-cell or 7-cell. Also, if you compare - Lipo 2S is 7.4v and NiMH 6-cell is 7.2v. 7-cell would be "out of spec" if your track has such a limitation.

Most discharge trays are geared toward equalizing batteries so that you start with the same discharge amount for all cells before charging up. With 7-cells, you'd have to discharge 6-cells and then 1-more. This wouldn't be a problem with a 6-cell setup. However, a charger with a discharge mode only discharges the whole-pack and not individual cells.

You can get by without discharging, just re-charge at lower amps such that the cells tend to equalize (a slow charge every week or two). Howver, if you do find that you must use 6-cell or LiPo 2S (7.4v) at the local track - then you may just want to go lipo and not worry about all this.

If you're not racing but just bashing - then 7-cells is the way to go and maybe two "sport" packs which you would treat with less care than if you were racing.
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Old 11-28-2008, 01:25 PM   #26
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Quote:
Originally Posted by racer357 View Post
the slash will accept lipos with out any mods at all. the stock speedo will handle up to 3 cells lipo with no issue at all.
The stock XL-5 speed control will not accept 3s and wont arm because of the high voltage protection it has. It will arm and run on a 2s lipo but it has no LVC so running lipo would be some what risky to the lipo itself unless you added an external LVC.
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Old 11-28-2008, 01:27 PM   #27
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perhaps with exception of some1 tryin something (granted new 4600 stuff is not allowed even if it was faster) but more likely the folks just gettin started in hobby. every1 in bumps and jumps slash class is on a lipo. most people buy the combo from chris where u get the truck, an onyx 230 and a 4000mah lipo for 315bux cash n race...

...what i did last wk, yeh i missed 1st rd gettin it ready but hey i only bought it 90min b4.

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Old 11-28-2008, 05:21 PM   #28
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Electric is a whole lot easier on everything than nitro... Your wallet.. nerves.. ears... etc... lol..

I will agree that the only cells that consistently seemed to explode for no reason are the NiMH IB cells... everybody else that blows one up was from using the wrong charger profile, over charging, or from just charging them too long..

With lipos.. the whole process gets easier and safer.. ya a lot of the first guys to use them were in new territory.. mostly airplane guys a few years ago. We've been using the newer generation for the past year at our local race track.. I havent seen or heard of one person having a problem that wasn't their fault.. and we only use hardcased packs so no big explosions or anything.. just some smoke.

The Slash races are really taking off everywhere. So easy to buy, maintain and race. Check with your local track to see what types of batteries they are allowing because it can vary quite a bit especially if the local track is trying to run it as a SPEC class.


Have fun!

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Old 11-28-2008, 06:58 PM   #29
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I have to agree with JeromeK99 that the lipos really are very safe, I have yet to see one burst or catch fire. The big advantage to lipo versus nickel metal is that you can race with only one battery (if cash is real tight) instead of having to buy 4 or 5 packs just to make it through one night of racing. I waited to get into electric just for that reason. Brushless and lipo makes the racing almost maintenance free. Just don't charge more than 1 amp per 100 mah of battery capacity and don't discharge below 6.5-7 volts (most good speed controllers have a lipo cut-off, so it is idiot-proof) and you shouldn't have any problems at all.
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Old 11-28-2008, 09:14 PM   #30
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I'm actually into RC only for bashing. I have no tracks near me anyway lol (NYC). But i do have a huge park of just sand right next to my house which is nice. So i guess i'm looking mainly for durable and affordable equipment. Now i am thinking this: Traxxas Slash, Duratrax Onyx 230 charger, Pro-match 7cell 4600mah battery, and some discharge/balancing tray. The Onyx 230 doesn't have discharge or balancing but i'm leaning on the discharge/balancing tray to do that job. I'll charge the battery with a low current everytime. I'm glad i know cells are safer than what other people are making it out to be though lol. I thought i would have to baby them or else they'd explode on me everytime. Because i'm actually pretty sick of nitro, expensive fuel, non-stop maintenance. It really takes the fun out of this hobby when something breaks or malfunctions almost every time you use it.
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