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Old Jul 05, 2013, 11:20 PM
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Help!
Gental Lady ARF CG problem

I started when I was about 12 flying gliders.. have not done it for YEARS.. (yeah I just turned 48)

so today I bought a Gentle Lady figuring that would be an EASY get back into glider ..plane.

got it all together just as the instructions tell you to build it.. and I am WAY tail heavy..

Now this is the ARF version so I KNOW I did not add to much weight to it.. almost no way you can..

I am using a LIFE 1100 mAH battery and it is as far forward as it can go (right against the back of the "nose cone"

I am using standard size servos.. and since I did not have a spektrum receiver I chose to throw in an OLD 72 Mhz futaba 7 channel receiver that I had from YEARS ago.. just to test her out..

so I mark the CG at 3 5/8 in back from the leading edge.. and to get it to balance.. I had to add almost 4 OZ of lead up beside the battery..

Now I can see maybe an OZ.. but 4 OZ seems like a TON.. has anyone flown/built one of these and did you have to add a ton of nose weight??

thanks in advance!
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Old Jul 05, 2013, 11:28 PM
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Better to start there and try moving the CG back slowly later.

Gentle Ladys will carry a surprising amount of weight, and probably penetrate better with a little ballast. 4 ounces isn't that much.

edit- I'll bet you my kit built version is heavier than your arf. What's your all-up-weight?
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Old Jul 05, 2013, 11:30 PM
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Quote:
Originally Posted by slopemeno View Post
Better to start there and try moving the CG back slowly later.

Gentle Ladys will carry a surprising amount of weight, and probably penetrate better with a little ballast. 4 ounces isn't that much.

Awesome it just seemed like a lot.. so I figured I'd ask!

Thanks for the input.. I went with the 1100 Life because it was smaller... heck I should have got the 2200!! I could fly it for WEEKS on that LOL
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Old Jul 05, 2013, 11:39 PM
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I have a 4-cell 1500 in mine made from an r/c car pack that probably weighs 12 ounces, and it's right on the CG. I have a huge chunk of lead in the nose to balance it too. Still will fly in some incredibly light air.
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Old Jul 06, 2013, 12:02 AM
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I use a 2200 3S Lipo in mine all the way foreward and it balances spot on.
It is the kit built and at minimum weight. Would have to take weight out of the tail to go less.
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Old Jul 06, 2013, 12:47 AM
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I'm using a 2800mah NiMH and I still had to add weight. I think battery and weight is around 7-8oz. I did rebuild my tail feathers with heavy wood after my super light ones broke launching on a windy day. I can still work super light lift.
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Old Jul 06, 2013, 05:44 AM
Kurt Zimmerman ≡LSF 4461≡
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What is your AUW? I seem to recall my GL was about 28 oz. built from a kit.
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Old Jul 06, 2013, 08:17 AM
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Quote:
Originally Posted by kzimmerm View Post
What is your AUW? I seem to recall my GL was about 28 oz. built from a kit.
Well from the answers It looks as if I am ok! I just wanted to be sure!

AUW?? I am sure that has something to do with final weight.. I dont have a scale that reads over 16 oz but right now the Fuse weights about 14 oz (no nose weight added) and the wing weighs 12 OZ so about 26- 27 OZ total. with nose weight I should be close to 30 oz
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Old Jul 06, 2013, 09:35 AM
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Mine weighs 25 ounces.
It is also the minimum weight stated in manual so that has to be for CG reasons I guess.
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Old Jul 06, 2013, 10:04 PM
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30 ounces is ok for a glider this size. I don't know how much an 1100 mah LiFe pack weighs, but originally this must have been designed for a 4 oz. battery pack, 2 ounce receiver, and servos in the 1.5 to 2 oz. range.

If the c.g. you are using is from the instructions, it's probably conservative and you may be taking some of that nose weight out eventually.

It seems possible that some of the wood in the tail may be a bit heavy.
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Old Jul 07, 2013, 09:22 PM
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please let us know where you where you finally ended up with the cg mine which i converted to electric flys best a little nose heavy balanced at the corner of the sheeting (if that makes sense) about 3/8 to 1/2 inch in front of recomemded cg
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Old Jul 08, 2013, 12:34 PM
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Quote:
Originally Posted by truckinhard088 View Post
please let us know where you where you finally ended up with the cg mine which i converted to electric flys best a little nose heavy balanced at the corner of the sheeting (if that makes sense) about 3/8 to 1/2 inch in front of recomemded cg
will do I have it at the factory recommended spot. and a touch nose heavy for the first flight.. should be saturday!
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Old Jul 08, 2013, 03:35 PM
It's GoTime all the Time
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United States, CA, Portola
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Cut the nose off add a 28x36 1000KV outrunner with a 10x6 cam prop 30A esc and a 1300Mah 45C lipo and you have tons of fun.
I did this to my Sophisticated Lady. weight is 27oz
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Old Jul 10, 2013, 11:03 AM
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Originally Posted by gotime360 View Post
Cut the nose off add a 28x36 1000KV outrunner with a 10x6 cam prop 30A esc and a 1300Mah 45C lipo and you have tons of fun.
I did this to my Sophisticated Lady. weight is 27oz
Looks like fun... how do you come in lighter than I did?? thats whats confusing me?? I mean I KNOW she will fly like this but it just seems she is awefully heavy!
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Old Jul 13, 2013, 09:12 PM
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Well got in her maiden this morning..

She does float like a dream!

Stupid hi start was killing me though... 3 times the "rope" snapped on me so never got a really good start on it.. Arrrgh..

but did get some other great flights in so I am happy!

I really do like the idea of powering her..

So what do you think... is this a good choice for motors??

http://www.headsuphobby.com/Firepowe...otor-E-645.htm
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