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Old Dec 26, 2005, 01:10 PM
Too little play time...
WarrrEagle!'s Avatar
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Question
I have 3 7.4V 800 mAh 2s lipos.... So...

What would be a good motor/prop for them and about what size foamie profile model would it pull?

I am a big time newbie and am lost when it comes to all of the combos.

(I have a Blade CX heli and these are the batts for it. I might as well have a plane that uses them too for windy days.)

Thanks!
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Old Dec 26, 2005, 01:36 PM
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First we need to know the "C" rating of those packs. How many amps can they deliver?
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Old Dec 26, 2005, 02:33 PM
Too little play time...
WarrrEagle!'s Avatar
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Quote:
Originally Posted by perttime
First we need to know the "C" rating of those packs. How many amps can they deliver?
Hummmm....

No where on these batts does it give a "C" rating...

They are E-Flite # EFLB0990.

I can't seem to find that on the net either...

I'll ask on the heli board. Maybe someone ther knows the amps.

Thanks.
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Old Dec 26, 2005, 02:55 PM
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2C? I think that refers to 2 cell though...

????
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Old Dec 26, 2005, 09:18 PM
Too little play time...
WarrrEagle!'s Avatar
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I know I have not stumped y'all!

Advice, please?

Thanks!
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Old Dec 27, 2005, 01:42 AM
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Quote:
Originally Posted by WarrrEagle!
(I have a Blade CX heli and these are the batts for it. I might as well have a plane that uses them too for windy days.)
From my observations, it looks like helicopters are less sensitive to wind than fixed wing planes.

You could measure, or otherwise figure out how much your helicopter motor is drawing.

I found your battery in the net but there was nothing about discharge rates.
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Old Dec 27, 2005, 02:17 AM
Too little play time...
WarrrEagle!'s Avatar
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Quote:
Originally Posted by perttime
From my observations, it looks like helicopters are less sensitive to wind than fixed wing planes.

You could measure, or otherwise figure out how much your helicopter motor is drawing.

I found your battery in the net but there was nothing about discharge rates.
This little co-axial heli will not fly in any wind. A decent breeze is fatal...

Thanks anyway... I'm gonn ask on the other forum now. I'll post again if I figure it out.
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Old Dec 27, 2005, 10:28 AM
Too little play time...
WarrrEagle!'s Avatar
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Found it!

"7.4 V, 800 mAH, 10C discharge rating = 8 A"

"The 800mAh pack included with the BCX can handle discharge rates of up to 10C continuous (we will be publishing this data on our site soon). When used in the BCX, where average duration is typically 10-15 minutes per charge, it is being discharged at a rate of 4-6C. These are very comfortable discharge rates for a 10C discharge capable pack, and providing that the pack is not routinely overdischarged, it will provide many, many flights and very good cycle life (we have yet to discard any of the BCX packs we have used since we began testing, some with many, many dozens of flights on them, and they are still performing well)."

So, where can I go motor/prop/ESC/model wise?

Thanks again!
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Old Dec 28, 2005, 02:20 AM
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For cheap power, the GWS 350 motor and "C" or "D" gearing should work. The "D" gearing would let you use a bigger prop, which is usually better for slow flyers. Look at the tables at the bottom of 6this page:
http://www.gwsus.com/english/product...em/eps350c.htm

For brushless (more money/better efficiency) an AXI 2208/34 is one good option.
http://www.modelmotors.cz/index.php?...9%20-%2057%20g)

Both of these are widely available. There are dozens of more options.

You need ESCs that can handle 10+ Amps (it usually a good idea to have an ESC with a bit extra capabilities, to play it safe).

If it is your first fixed wing plane, you should take a high wing trainer. GWS Slow Stick, Beaver and E-Starter are good values but I am not sure which power systems are currently included in the kits. They might draw too many amps off the shelf. Again, these are not the only options.

Your batteries would be ideal for planes that are a bit lighter than the GWS planes.

I guess something from Foamyfactory, 3DBatix, or 3DFoamy would be great if you can handle aerobatic planes.
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Old Dec 28, 2005, 03:51 AM
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WarrrEagle!'s Avatar
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Thank you kindly!

So it would pull a smaller foamie FFF profile around OK?

That is just the info I needed.

I have a pretty decent amount of gasser time and just a bit of electric. I am building a Nasty right now.

You are a scholar and a gentleman!

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Old Dec 28, 2005, 04:05 AM
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I think the Nasty should be OK, just keep it light. You need to be careful not to overload the battery: select a prop and gearing (if any) that keep the Amps at a comfortable level. I do not think that you will have the power for hovering or unlimited vertical, though, and you should not fly at full power all the time. Have mercy on your poor little battery

I have not stopped learning yet.
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Old Dec 28, 2005, 04:26 AM
Too little play time...
WarrrEagle!'s Avatar
South Alabama
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I have a set up for the Nasty ready to go with 3 3 cell GWS 11.1V 1300mAh running a Tbird ESC and a CD Rom motor a friend wrapped.

I'll buy a set up for a smaller, lighter foamie to use these wee batteries with.

Now just to decide which to make...

Thanks again. Seriously.
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Old Dec 28, 2005, 05:21 AM
Naturally altered
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These batteries will work great in a GWS Pico-Cub or Tiger Moth.
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Old Dec 28, 2005, 11:14 AM
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WarrrEagle!'s Avatar
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Quote:
Originally Posted by Cubber
These batteries will work great in a GWS Pico-Cub or Tiger Moth.
Ya know, that is a great idea! I was handling a Cub at the LHS the other day... It was the first electric I ever flew aside from my ABC. A friend basicaly forced his TX into my hands but boy was it a sweet flyer!

Is the stock motor adequate?
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Old Dec 28, 2005, 11:58 AM
Naturally altered
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Quote:
Originally Posted by WarrrEagle!
Is the stock motor adequate?
Yes it is, in the way it was designed to be : a very lightweight plane, slow flying enough to be used indoors. Outdoors, of course, anything but the slightest breeze is not your friend. Should you need more power, the upgrade path is simple and not expensive : an IPS dual motor system is a no hassle fit, will double power adding only half an ounce and is well within the capabilities of your batteries. By carefully selecting the gearbox ratio, you can even use the same prop.

Another non brushless option that would work well with your batttery is a 280 class motor direct drive with a Gunther prop. Lots of power and speed for a Pico. A GWS 300 could work keeping amps low, and a 350 is too much for the batteries. Now the downside of the bigger can motors is they don't fit well on the stick with the cowl, you'll have to devise another motor mount.

And then, there's brushless but that's another story
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