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Old 08-08-2006, 02:14 AM   #16
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Quote:
Originally Posted by Turbo Joe
Wow.

I can smell that from here.
there's a good case for the nitro is safer brigade!
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Old 08-08-2006, 08:08 AM   #17
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What kind of insulation was used to prevent battery to graphite contact? Perhaps it was worn through?
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Old 08-08-2006, 08:41 AM   #18
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BEEN THERE DONE THAT
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Old 08-08-2006, 09:47 AM   #19
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not to mention the Fusion battery bars are scary....you are just asking for a short with those stupid (and pointless) heatsinks.

Last edited by Aaron Waldron; 08-08-2006 at 11:46 AM.
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Old 08-08-2006, 10:27 AM   #20
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Quote:
Originally Posted by Rick Hohwart
What kind of insulation was used to prevent battery to graphite contact? Perhaps it was worn through?
the pack only had 4 runs on it. Its possible that the shrink wrap wore through that fast.

I think those evil EVIL battery bars had something to do with it
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Old 08-08-2006, 10:30 AM   #21
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Thats the best excuse Ive ever seen to get a new car...
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Old 08-08-2006, 10:45 AM   #22
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Originally Posted by Z_Schneider
Thats the best excuse Ive ever seen to get a new car...

hmm.. I think you are on to something
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Old 08-08-2006, 11:42 AM   #23
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ouch good luck fixing it up
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Old 08-08-2006, 11:57 AM   #24
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Quote:
Originally Posted by Buckyaga
the pack only had 4 runs on it. Its possible that the shrink wrap wore through that fast.

I think those evil EVIL battery bars had something to do with it
he means bewteen the chaisis and the ends of the cell, where the battery bars are, those can't come in contact with the graphite, Losi kits come with a clear sticker thing that you put on inside the tub, Persoanlly I put a layer of electrical tape,
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Old 08-08-2006, 12:34 PM   #25
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Quote:
Originally Posted by bobf24
he means bewteen the chaisis and the ends of the cell, where the battery bars are, those can't come in contact with the graphite, Losi kits come with a clear sticker thing that you put on inside the tub, Persoanlly I put a layer of electrical tape,
Even this insulator can wear over time and if your positive and negative bars touch the chassis, your battery will short out and burn up.

I only mention it because I could not see any insulators. Maybe they can't be seen, or they were burned away. But not using them will cause the problem you experienced.
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Old 08-08-2006, 12:39 PM   #26
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Quote:
Originally Posted by Rick Hohwart
Even this insulator can wear over time and if your positive and negative bars touch the chassis, your battery will short out and burn up.

I only mention it because I could not see any insulators. Maybe they can't be seen, or they were burned away. But not using them will cause the problem you experienced.
Rick- Would that really cause it to blow up? I thought it would only cause the cells to vent.
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Old 08-08-2006, 12:51 PM   #27
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Quote:
Originally Posted by rcdude19641
Rick- Would that really cause it to blow up? I thought it would only cause the cells to vent.
Cells will vent to release pressure build up, especially during charging. They during discharge as well.

But if the + and - leads touched the graphite chassis at the same time for an extended period, and the pack had a decent amount of charge remaining, it would be just like soldering the leads together. The pack may vent initially, but the short circuit would continue until the connection (battery bar, chassis contact, internal cell construction) was broken.

This may or may not have happened. But if I had been presented with this warranty claim, the first thing I would ask is "was the chassis insulated?"
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Old 08-08-2006, 01:29 PM   #28
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I applied 7.2 volts from a charged IB3800 pack to an uninsulated graphite MF2 chassis and could only measure 300ma of current flow. While I do have my chassis insulated with tape, it does not appear that on my Losi chassis, enough current could flow to cause anythign other than a slow discharge.

Perhaps the surface conductivity of the chassis can change over time as oxidation occurs, but on a couple year old chassis that I tested, conductivity was poor.

Anyone else want to try?
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Old 08-08-2006, 02:20 PM   #29
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Two leads from a digital ohmeter, on the chassis one inch apart. If I really dig them into the chassis, I can get 500 ohms of resistance as a minimum. Unless my MF2 doesn't really have a graphite chassis (despite the words Graphite XXX on the bottom ), the odds of a battery short against it causing any significant current flow appear non-existant.

Don't get me wrong, I'm not claiming to be an authority, but aside from a slow current drain and probably radio noise from the shorting, it doesn't look like a graphite /plastic Losi MF2 chassis can conduct fire starting, battery popping current. Perhaps the strands in a carbon fibre sheet are another story, but that wasnt the chassis material shown here.
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Old 08-08-2006, 08:40 PM   #30
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I think I can see remnatts of the insultion in some of the pictures, so possibly the answer is yes to Rick's question.
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