12volts and Grass :-(

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007Kiwi
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12volts and Grass :-(

Post by 007Kiwi » Tue Jan 25, 2011 8:00 pm

Ok guys need the tech heads on this one to sort me out....

after a marathon 1 year long rewiring Job (moved houses etc etc) I finally got mobile last night (Hurray) :D

Concrete path no issues... catapillar spin no probs (track forward other track back) Once I hit the grass I could hardly turn at all (Lock one track up power on other) Bugger all movement at full throttles in a turn :(

I run a 12volt 38 amp main battery with twin Electronise ESC's with a 6 Ch Hitec Optic 6 Tx.

Do you think this is just a case of Power lacking from 12 volts and a 24vlt chain motor setup would fix?
or could it be simply throttle is not fully reaching 100% (the motors seem to spin sprockets rather slow, but its been a while since I got it moving so I have no reference point)

Any ideas on where to look to sort this?

Thanks

Brett
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BigPanzer
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Re: 12volts and Grass :-(

Post by BigPanzer » Wed Jan 26, 2011 4:08 am

Hi Brett,

From your description my first thought would be the battery. I've come across gel cells that seem to take a slow charge OK, measure the full voltage after charge and will run a model for some time where there is only a moderate current demand (like running on concrete) but they can't supply the higher current required for turns on a more grippy surface like grass.
My guess would be that it is reaching the end of its useful life and has partially suphated up.

My 2p worth

Peter

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Re: 12volts and Grass :-(

Post by 007Kiwi » Wed Jan 26, 2011 6:46 am

Hi Peter,

That makes sense, as the bloody thing sat there unused..... bahhhhh my fault
may need to test the amps comming out... :?
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Re: 12volts and Grass :-(

Post by 007Kiwi » Wed Jan 26, 2011 8:28 am

ps Turning the Speed control end points up to 125% helped.... ahhh heaps :oops:

(they can be set at 25% thru to 125%) pays to read websites :D

my bad, goes much better now :ugeek:
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JohnD
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Re: 12volts and Grass :-(

Post by JohnD » Wed Jan 26, 2011 12:16 pm

Hi Brett,

Could be the battery, but could also just be the motors stalling due to insufficient grunt - depends on the power of the motors. I had a similar thing with my JS2 which would not easily neutral turn on wet grass, fine on 'slick' surfaces. This has 250watt motors as bigger ones won't fit, they were 24v motors but running on 12v - changed to 24v and it now runs fine.

John
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Re: 12volts and Grass :-(

Post by Humpy » Wed Jan 26, 2011 1:33 pm

And of course, Electronize ESC's aren't infallible! What model is it Brett? I had electronize in my JP and they were ok but they didn't give it the grunt that 4QD's give.

To prove the battery, put a voltmeter across it while trying to do the turns. The V shouldn't drop too much but if it drops by more than a Volt or two then the battery's US.

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Re: 12volts and Grass :-(

Post by 007Kiwi » Wed Jan 26, 2011 7:46 pm

Thanks All.

Humpy the ESC's are the 30AMp FR30HX, cheers for the test idea
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Re: 12volts and Grass :-(

Post by Humpy » Thu Jan 27, 2011 9:10 am

Brett,

Yes, but what's the model? For a smaller model they will be ok but for a larger model they struggle a bit!

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Re: 12volts and Grass :-(

Post by 007Kiwi » Thu Jan 27, 2011 9:23 am

eh Mark -1 Tiger 1 with uranimum coated fibreglass and geared box (well it makes me itch like a bugger like it is) :D
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Re: 12volts and Grass :-(

Post by Humpy » Thu Jan 27, 2011 1:39 pm

So, quite heavy then! Mind you, presumably it has been ok? If so, I'd plump for a new battery sounds like it may have had it's day...

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Re: 12volts and Grass :-(

Post by 007Kiwi » Fri Jan 28, 2011 5:42 am

:shock: Your supposed to be the bearer of good news..... :D :D :D
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Re: 12volts and Grass :-(

Post by Humpy » Fri Jan 28, 2011 8:28 am

Sorry Brett, I only speak the truth :angelic-green: Maybe!! :)

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