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timmeh
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lol maby its the shit dick smith solder im using would not surprise me nothing they sell is quality.
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Post Tue Dec 23, 2008 7:09 pm 
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timmeh
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hmm went from 2mm copper wirerods to copper braid dosent seem to pop off now but it dosent take much to pull them off any shock would prob bust them.

I know braid has flex but still the bars should not have poped off that easy.
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Post Tue Dec 23, 2008 8:02 pm 
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andrew



Joined: 16 Jun 2004
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weird man, on the few packs i made dremeling the ends rough and using 12 g wire seemed to work ok, how odd

worst case look into solderless tube packs
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Post Tue Dec 23, 2008 10:23 pm 
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Valen
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silver solder has a *much* higher melting point than normal stuff.

tin/lead is probably the best bet for that kind of things, but your best off not soldering the cells if you can avoid it.
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Post Tue Dec 23, 2008 10:23 pm 
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timmeh
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where do you buy tube packs?
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Post Wed Dec 24, 2008 11:18 am 
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andrew



Joined: 16 Jun 2004
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http://www.modelelectronicscorp.com/browse_product.php?pid=29

basically you put the heatshrink over the bare cells which comes with, apply some funky conductive sludge to the end of the cells which also comes with the kit, slide em into the tubes and clamp the whole lot together with some very thin threaded rod and nuts.

Only issue is balancing the cells would have to be done after every event and mid event balancing would be hard unless you make up some jig to put every single cell in

My plan is to make up a lil jig and before and after the event i can balance the cells easily then re-assemble the packs.
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Post Wed Dec 24, 2008 12:50 pm 
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Glen
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theres a few mods out there where people have just soldered some really thin sheet to the outside of the cells and ran the balancer wires out the middle. was gunna do that myself except i kept physically breaking the packs Confused
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Post Wed Dec 24, 2008 1:04 pm 
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timmeh
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What is the lowest discharge voltage for a123 cells?

Looking for a cutoff jigy to hook up to the reciever.
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Post Mon Dec 29, 2008 8:36 pm 
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Nick
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Did you read the fine print about the Liposhield only working with single direction ESCs? they won't help you if you use reversing controllers Mad

Post Mon Dec 29, 2008 9:31 pm 
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timmeh
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ahhh lol Very Happy

Hmm maby something can be made.
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Post Mon Dec 29, 2008 9:32 pm 
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Valen
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bah don't worry about it.
you probably wont flatten an A123 pack anyway
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Post Mon Dec 29, 2008 11:13 pm 
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Glen
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anything under 2.9v and mine seem to never take a full charge again. i think thats the problem when i had them powering the dewalts, it was just discharging them way too far and theyd go out of balance exceptionally quick.

you can get lipoly wireless devices at united hobbies that plug into the balancer port on the battery and transmit back to a little box you put on the transmitter and it beeps when the battery is too flat.

i think they might have a a123 setting but im gunna get one for my rc car soon Smile
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Post Mon Dec 29, 2008 11:20 pm 
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timmeh
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will be running large brushless motor and two large drill motors.
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Post Tue Dec 30, 2008 8:01 am 
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Rotwang
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Joined: 15 Jun 2004
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Well the $ per cell equation seems to has shifted in favor of LiPo’s by the look of it.
Only thing that concerns me is how fast can you get away with charging LiPo’s.
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Post Tue Dec 30, 2008 11:27 am 
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Nick
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Most manufacturers recommend 1C charging rate. If you know about how discharged the packs are, you can get away with a 2C rate to begin with. A few of the latest technology packs are OK for 5C. I find the most important thing is to cool the packs down to room temp. before recharging.

Post Tue Dec 30, 2008 12:24 pm 
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