Hovercraft B/C

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Re: Hovercraft B/C

Post by LittyWap »

Most likely, the damage is irreversible. I tried LiPo's and after the proctor prevented us from using a voltage meter (to make sure it didn't discharge to the point were it couldn't be charged again) for fear that it gave us an unfair advantage, we nearly fully discharged the battery, and it was never quite the same. It never charged fully, and was warmer than normal...

In the (slightly paraphrased) words of the Insane Clown Posse: "pigeon' Batteries, How do They Work?"
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Re: Hovercraft B/C

Post by LittyWap »

LittyWap wrote: In the (slightly paraphrased) words of the Insane Clown Posse: "butterfly' Batteries, How do They Work?"

I guess the forum Gods don't like true artistry, censorship and all. And just for reference, that song is awful.

Skip to 1:50: https://www.youtube.com/watch?v=8GyVx28R9-s
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Re: Hovercraft B/C

Post by antoine_ego »

Ashernoel wrote:do NiMH batteries lose voltage faster the more you use them? Since I've started testing the batteries have been getting "weaker" from their top voltage faster. Is this expected? Could it be from overcharging because I charge them with a 3A current?
3A!!!! That's... really really high. I charge my 5500mAh at 0.5A maximum to be safe. Generally, you don't want to charge them over C/3 a lot (or at all really), which for my 5500mA battery, would be about 1.8A. I'm not too sure about this, but I've heard that charging at a high rate can potentially cause a battery to vent (release toxic gas).

Please, please, please, charge at lower current.
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Re: Hovercraft B/C

Post by ericlepanda »

LittyWap wrote:Most likely, the damage is irreversible. I tried LiPo's and after the proctor prevented us from using a voltage meter (to make sure it didn't discharge to the point were it couldn't be charged again) for fear that it gave us an unfair advantage, we nearly fully discharged the battery, and it was never quite the same. It never charged fully, and was warmer than normal...

In the (slightly paraphrased) words of the Insane Clown Posse: "butterfly' Batteries, How do They Work?"
Why wouldn't you be allowed to use a voltage meter during your testing period? I'm pretty sure you should've been able to use it as long as it wasn't part of your hovercraft.
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Re: Hovercraft B/C

Post by cheese »

antoine_ego wrote:
Ashernoel wrote:do NiMH batteries lose voltage faster the more you use them? Since I've started testing the batteries have been getting "weaker" from their top voltage faster. Is this expected? Could it be from overcharging because I charge them with a 3A current?
3A!!!! That's... really really high. I charge my 5500mAh at 0.5A maximum to be safe. Generally, you don't want to charge them over C/3 a lot (or at all really), which for my 5500mA battery, would be about 1.8A. I'm not too sure about this, but I've heard that charging at a high rate can potentially cause a battery to vent (release toxic gas).

Please, please, please, charge at lower current.
If you guys are charging at a high current for it to go faster, instead just invest in another bunch of the same batteries so that when you aren't using them, you just charge them, and when you need to charge, just switch em out.
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Re: Hovercraft B/C

Post by SciHC101 »

We have a hovercraft that is quite sturdy, and uses a Potentiometer for tuning. My partner and I are having trouble getting the 25 second target time. Dp you have any suggestions?
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Re: Hovercraft B/C

Post by Ashernoel »

SciHC101 wrote:We have a hovercraft that is quite sturdy, and uses a Potentiometer for tuning. My partner and I are having trouble getting the 25 second target time. Dp you have any suggestions?
1) hope it isn't the 25 second target time
2) sloooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooww so that it barely moves the first 10s and then picsk up pace lol
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Re: Hovercraft B/C

Post by antoine_ego »

SciHC101 wrote:We have a hovercraft that is quite sturdy, and uses a Potentiometer for tuning. My partner and I are having trouble getting the 25 second target time. Dp you have any suggestions?
Odds are that competitions won't ask for a 25 second time. Generally, from what I've seen, they never ask for either really long or really short, usually it's around 15 plus or minus 6 seconds.
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Re: Hovercraft B/C

Post by LittyWap »

antoine_ego wrote:
SciHC101 wrote:We have a hovercraft that is quite sturdy, and uses a Potentiometer for tuning. My partner and I are having trouble getting the 25 second target time. Dp you have any suggestions?
Odds are that competitions won't ask for a 25 second time. Generally, from what I've seen, they never ask for either really long or really short, usually it's around 15 plus or minus 6 seconds.
At our regionals, the proctors, who were quoting as saying "I haven't even looked at this rulebook until today" choose 25 seconds. I doubt anyone is going to be that annoying at States/Nats, so I'm assuming 5-15 seconds. The regional proctors were so bad in fact, that they let a vehicle run 5 times more than the target time, clamped the rails upside down, and didn't test anyone for the quarter inch shielding rule. I had to give them a scrap of quarter inch I had, showed them how to clamp the rails, and even showed them how to prevent their table from bowing. I doubt any state/nat proctor is going to be that bad.
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Re: Hovercraft B/C

Post by Unome »

LittyWap wrote:I doubt any state/nat proctor is going to be that bad.
Based on the numerous bad experiences that I've had over the years, I will dissent here. There are plenty of state event supervisors that are this bad, though of course it depends on the state (of the remaining state tournaments thiss year, I'd say one would encounter maybe 1 or 2 state event supervisors that bad). Nationals - usually if you get a bad event supervisor, they will be in a pure testing event; the builds and hybrids tend to be very well-run.
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