# 8 AA to a battery block?



## cape cod Todd (Jan 3, 2008)

Hello to All
I'm working on a project where I want to build a racing caboose by using a bachmann bobber and an old radio control car I have. Back in the day I had HO trains and would race hustler engines on long staightaways. These engines had a motor in the middle a shaft forward and back which was connected by rubber bands to the 2 drive axles. A very simple arrangement and one that can be easily copied to G scale.... I think. 
I know it will be like running a slot car but that is what I want. The car has 4 speeds fast, faster, faster still and light speed. 
If it works out I will build 2, set them at oposite ends of the mainline and see who is the better driver to catch up with the other without flying off the track. Going around curves should be a practise in coasting.
The 2 RC cars I have require 8 AA batteries each I would like to get the more modern, blocks, sticks, packs or whatever they call that long battery which is easy to handle and charge up. Do I add up the volts? the blocks seem to come in different sizes, volts, how will I know what will work and what to avoid so as not to cook my old RC motor? 
Thanks


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## Del Tapparo (Jan 4, 2008)

If you are now using regular batteries, they are 1.5 volts per cell; so 8 X 1.5 = 12 volts. Rechargable batteries are 1.2 volts per cell; so 8 X 1.5 = 9.6 volts. If you are going for speed; more volts will produce more speed, up to the point of damaging electronics or motors. You need to know some specifications of your equipment before trying that.


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## sailbode (Jan 2, 2008)

Hi Todd, Seems to me that the typical RC car uses 7 or 8 cells which = 8-9 volts. I believe most of those "can" motors can handle a few more volts which will increase the speed and load. Perhaps an in line fuse might be a good idea. The load (drag) of a caboose will probably be less than an RC car. I would experiment with 8 and then 9 cells. Run it a little and then check the temperature of the motor. I'd also moniter the temp of the battery pack.


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## Greg Elmassian (Jan 3, 2008)

Dell put a minor error in his post, but got the right answer, 8 cells at 1.2 volts is 9.6 (he accidentally typed 1.5) 

If your car now runs on 8 AA alkalines, then 12 volts from cells that make 1.2 volts would take 10 cells (10 * 1.2 volts each) . 

So you could start with the same voltage in rechargeables as you are using now. 

This way you would be running the same voltage. Have you ascertained that the current speed is what you want? 

You could even find 12 volt gel cells if you have the room. Heavier, larger, but maybe the weight would help, and they are less expensive. 

Regards, Greg


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## Pete Thornton (Jan 2, 2008)

the blocks seem to come in different sizes 
Todd, 

I get NiMH batteries from *http://www.batteryspace.com/capacit...packs.aspx* (The link is their 12V page.) 

They have packs arranged in any conceivable array - here's a typical 12V stack: 










I strongly recommend getting a "smart" charger which senses when the batteries are full - you just plug in and forget it. Like this one: 

*http://www.batteryspace.com/multi-c...isted.aspx*


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## altterrain (Jan 2, 2008)

Li-ion pack of 3 cells for 11.1 volts - 











much smaller and liighter 
nice sale price going on now! - http://www.all-battery.com/li-ion18...ction.aspx 

-Brian


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## cape cod Todd (Jan 3, 2008)

Thanks guys you have all given me a helping of food for thought. I like the battery packs I was directed to they seem to be small, lite of weight and economical. The chargers on the other hand can be expensive. This little project needs to be kept just that, little = low cost. I need to save money in case a Bachmann Heisler makes itself available. 
Once the build is underway I will keep you posted on its progress. 
Todd


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## Greg Elmassian (Jan 3, 2008)

Buy a small AA holder or two, enough to put in 10 nicads. 

Then buy a small, cheap AA charger. 

Everything available from Radio Shack. 

More work to pull batteries out and recharge, but if low cost is a priority, then you have to give something else up. 

Regards, Greg


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## Stan Cedarleaf (Jan 2, 2008)

I would agree with Brian on the 11.1 cells. They'll run a whole lot of locomotives quite nicely.

Here's a bit better "deal" It says 4400 on this image but it's 5200 in the ad. 












11.1 Volt 5200 mAh Li-ion

Then use the TLP-2000 Charger  set at 11.1 charging rate.

I run the 11.1 6600 pack with my Doodlebug pulling a heavyweight and 3 box cars with 6 hour of run time. A Hartland Big John will get 8 hours of run time with the 6600. I got them a year ago when they were $30 a piece...









The 5200 is a very good "deal".


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