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Old 12-13-2006, 12:58 PM   #1
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Default Weak packs, dead cell?

I have a few packs that I bought used off of this site. They are weak, and I have 1 cell in the weak packs that always goes out immediatly on the discharger (Novak Smart Tray), do I just assume that this is a bad cell?

How do I figuer out which is the bad cell? Does anyone offer a rematching service?

This really sucks. The guy who sold me these packs also sold me a motor with a bent armature.

Luckily Eric Anderson (The EA in EA Motorsports) will sell me new cells matched to these packs to repair them. I just need to identify the bad cells.
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Old 12-13-2006, 01:20 PM   #2
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We can re-match your packs for you. What kind of batteries do you have IB 3800's or IB4200's? We will also replace the Bad batteries with compatible used cells if you like at no cost other than shipping to us and back to you. I will do this seeing that you are new to R/C and you are an enginering student. Let us know.

Thanks, Duane at RCPROFESSOR
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Old 12-13-2006, 01:21 PM   #3
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How can someone sell a bent arm... better yet, how do you bend an arm, drop it, throw it at the wall...
buying used packs is always buyer beware...
My friend that still races just got new packs, and him and his friends just give old packs away to people who need them. Always asking people, how many motors do you have... What kind of batteries do you have... If they have an extra battery charged at the end of the night they will slip it to someone to run in their main... It keeps the new people interested. They pretty much just give stuff to people who only have a few batteries, and 1 or 2 motors...
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Old 12-13-2006, 01:34 PM   #4
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WOW. I will send you a PM Duane.

As far as the motor, I don't know, but tit didn't burn my buns so much. I previously wrecked the endbell of an identical motor trying to align the brush hoods so I just have a totally junk motor and a tuned motor with a basically new armature, and experiance that tells me that saving $10.00 messing with motors myself isn't such a good idea yet
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Old 12-13-2006, 01:39 PM   #5
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No problem glad to help you out of a jam.
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Old 12-13-2006, 05:47 PM   #6
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Quote:
Originally Posted by DCARD
No problem glad to help you out of a jam.
Dude that is a very nice and standup thing to do for a racer in need, i RESPECT that move peace.
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Old 12-13-2006, 06:12 PM   #7
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In case you're interested, it can help to identify a bad call in a pack by performing the following:
Discharge the pack completely, and put it on a quick charge. Get two test leads with sharp pointed ends and connect them to your DVOM (digital Volt/Ohm meter) and pierce the shrinkwrap at various points across the pack to read the charging voltage of each cell. You will eventually find a cell that has a voltage thats way off compared to the others. This will be your bad cell.
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Old 12-13-2006, 06:50 PM   #8
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Quote:
Originally Posted by DCARD
We can re-match your packs for you. What kind of batteries do you have IB 3800's or IB4200's? We will also replace the Bad batteries with compatible used cells if you like at no cost other than shipping to us and back to you. I will do this seeing that you are new to R/C and you are an enginering student. Let us know.

Thanks, Duane at RCPROFESSOR
I am a relatively new racer also and all I can say is it's the people like you that make this hobby awesome!!
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Old 12-14-2006, 05:06 AM   #9
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Thanks all for the kind words. Brian and I just try to do the right thing. Many of the matcher out there would do the same thing to help new guys out. If no one helped us 15 years ago we probably would not be here today.

Gump you are correct using a volt meter on your cells while charging can detect a bad cell. Also when your cells are at rest you can most times find that bad cell using a volt meter. Look for signs of venting on the + side of the cell. If you see white crystals chances are your cell has vented. Not all cells are or do go bad after venting. But chances are good that that could be your bad cell.
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Old 12-14-2006, 06:36 AM   #10
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Quote:
Originally Posted by Section 8
I have a few packs that I bought used off of this site. They are weak, and I have 1 cell in the weak packs that always goes out immediatly on the discharger (Novak Smart Tray), do I just assume that this is a bad cell?

How do I figuer out which is the bad cell? Does anyone offer a rematching service?

This really sucks. The guy who sold me these packs also sold me a motor with a bent armature.

Luckily Eric Anderson (The EA in EA Motorsports) will sell me new cells matched to these packs to repair them. I just need to identify the bad cells.
Cells decline in performance as they get used over time. A new cell with the same label numbers isn't really the best solution unless you rematch and find a cell with the same new-matched data.

Never buy used cells unless you KNOW the person selling it! (ie someone you KNOW who takes care of their stuff or personal friends who sell off practically new cells after a big race!, guys like that!)
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Old 01-02-2007, 08:47 PM   #11
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I got my packs back from RC Professor last week, but I just got the package today (the mail room had odd hours last week, and I missed the hours they were open ). I think that I sent them in on dec 20th, so they had them basically all of 2 days before they were back in the mail to me.

Anyway, RC Professor rematched all of my cells from the 4 packs I sent in, and replaced the bad cells. When I opened the box I had a suprise, or a free gift, or a toy at the bottom of the box so to speak. I had to go change my underwear, because they included a 5th pack on the return trip. Its a low runtime pack, but a 4200 pack with 380-390 second specs (35 amp) are hardly a problem with a 5 minute heat/main particularly in stock, I could probably still use it twice with 2 heats. Voltages averaged across the pack put it at 1.236 volts (again, 35 amp) so I essentially got a good stocker pack for free.

Now, this makes me think that getting ripped off in the first place was a good thing . I ask for some help on the board on what I should do about dead cells in a pack, and I end up with rematched packs along with a free pack, not to mention finding a place where the guys are clearly interested in carrying the hobby farther, and being helpful to a naive new guy with no money (who the hell wants to help out "that guy"? ).

Does this mean that I am sponsored now? I get free stuff...
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Old 01-02-2007, 09:03 PM   #12
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I guess RCProfessor is obviously Santa Claus in disguise...

FYI...You can receive bent armatures on brand new motors directly from the manufacturers. Motor builders/rebuilders check this stuff for you.

Buying such thing sight unseen from unknown sourcs is bound to get you into such predicaments.
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