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Old 05-13-2009, 03:55 PM   #1
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Default need some temporary Rx battery advice

I went to the track Monday to find out that my Rx NiMH pack won't hold a charge anymore. Turns out that it's not a 1 or 2 day fix becuase the local Batteries Plus does not stock and also cannot get cells anywhere close to the capacity I had anymore. No problem, I saw some advice about cheapbatterypacks.com last week and have one on order just like I want.
But Sat. will be here soon and I want to hit the track for a couple hours if it doesn't rain. I have the original holder for four alkalines but my Futaba fail safe says no maganese or alkali batteries. Something about the current demand on the batteries will mess with the low voltage shutoff feature. Anybody know if I would really have a problem? I don't want to run without a failsafe.
My other backup plan is the 4 regular AA NiCad cells I am slow charging right now to see if they are still any good - probably bought for my old camera I guess. Not used much so they may charge up, but 4 cell Nicad will be pretty low voltage. Doesn't matter MUCH though because it is just practice on a new layout I need to learn anyway.

What this really alerts me to is that I've carried that alkaline holder for the last two years thinking it was my backup for a failure or a long day. What's anybodys ideas for cheap or smart backups if your main pack is a 5 cell NiMH? A couple of dumb questions but I'm looking for some input!
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Old 05-13-2009, 04:03 PM   #2
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Keep the old AA holder and some back-up alkalines.
Then again, I don't run a failsafe.
I'm just awaiting the day my battery fails.......
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Old 05-13-2009, 05:24 PM   #3
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I always carry at least 2 5-cell Rx packs charged just in case. I had the old I only have one problem with a starter box lipo and something shorted out the battery and I did not have a backup. I was stuck with a decent qual and had to bum a bump to drive in the main. Good thing my engine was tuned right and no flame outs, but ever since then I carry 2 charged starter box lipos you never know when you will need it.

So the solution in the future is carry 2 Rx packs, as for right now all you can do is use the AA pack.
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Old 05-13-2009, 05:37 PM   #4
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Quote:
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I always carry at least 2 5-cell Rx packs charged just in case. I had the old I only have one problem with a starter box lipo and something shorted out the battery and I did not have a backup. I was stuck with a decent qual and had to bum a bump to drive in the main. Good thing my engine was tuned right and no flame outs, but ever since then I carry 2 charged starter box lipos you never know when you will need it.

So the solution in the future is carry 2 Rx packs, as for right now all you can do is use the AA pack.
Do you rotate your packs to keep them in shape? I have my custom pack sized to the extents of the radio box and would need to take the whole box apart every week to swap packs. I have no problem spending the extra $27 to get the 2nd identical pack BUT I gotta be honest, the rotating doesn't thrill me with my old stubborn setup. Maybe I could rotate them 6-8 times a season and keep them both charged over the winter. That may be a good plan. 1 step better than I was thinking before at least.
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Old 05-13-2009, 05:41 PM   #5
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I usually use the newest pack and then cycle them at least once per month depends on if I miss a race weekend or not. I keep the older pack for backup just incase my main pack takes a dump.
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Old 05-13-2009, 06:30 PM   #6
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Quote:
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I usually use the newest pack and then cycle them at least once per month depends on if I miss a race weekend or not. I keep the older pack for backup just incase my main pack takes a dump.
So the plan is to keep the 2nd pack as backup and only cycle it enough to maintain it. When the 1st pack fails, the 2nd takes over as the main pack with not much use on it but healthy.

Otherwise in theory both packs would fail the same season if you just used them both all of the time and rotated them often and had equal use right?


I guess for Sat. I'll see how long the Nicads last with the fail safe then switch to alkalines with the fail safe if the nicads wear out. Does anyone think the alkalines would hurt the fail safe?
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Old 05-16-2009, 07:38 PM   #7
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Well, I never had to worry about the alkalines. Even though the Nicad AA's had some of their insides coming out of the end of them they still charged up and lasted today.
I had to work and we had tons of rain but the afternoon was nice. My new custom pack showed up in the mail and was there when I got home so I took it with me to the track and started the first recommended slow charge. For $26 including shipping it is a very nice looking pack. Hopefully it will perform as good as it looks! They were quick too. I ordered it on Wed and it showed up today from OR to IN! I placed the order then replied to the confirmation email with a pic of my old pack and a quick description of it and never heard another word. I thought I would check on it Monday to see if there were any questions and it shows up today!
I will be getting another one later in the season because the AA holder absolutley sucks for fitting in my radio box with my receiver. It's going to damage it because the fit is smashed up against the Rx. Not good Not a very good backup plan for me. Another pack will be great I think
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Old 05-16-2009, 07:51 PM   #8
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cheap batterypacks.com is good ...nimh packs just crap out ...even when not abused they just drop off so quick ....but yeh what frank l said about having 2 good packs for everyday of racin is good advice ...at some point consider lipo rx packs ...they dont drop off unless they are damaged ...my 2000 mah pack will run practice and 3 heats with out a charge ....so down the road you may wanna think about it ...you can get chargers pretty cheap and they ar mainstream now ...and a good battery will run you 35-45 bucks but if taken care of will last a season or more .....

didnt know if you run a stick pack or hump pack ...prolly hump pack ...try one of these i you stick with nimh

http://www.carolinasrc.com/Webstore/...idproduct=4715
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