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Dec 25, 2019, 12:02 PM
flyin' fool
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Dec 25, 2019, 01:07 PM
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r/cdawg's Avatar
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Originally Posted by goldguy
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GWS 8x4.3 slow fly. I’m very impressed with the power that the little SunnySky motor is putting out and I’m already thinking of another indoor project for it.

I was a bit surprised by how much weight I had to add to the nose to get the balance right. I have 2 rather large steel washers temporarily glued to the nose which added about 12 grams which is kind of a bummer. I too am very careful not to add unnecessary weight but I have all the electronics as far forward as possible. Although it does fly great how it is.
Dec 25, 2019, 04:38 PM
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Did you say your cg was at 25% chord? Then I'm not surprised the plane is tail heavy...just look at the picture and note how much Stuff is aft of the cg.
Dec 25, 2019, 06:40 PM
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On the next version I could probably move the servos an inch further forward. It might help a little.
Dec 28, 2019, 08:41 AM
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Originally Posted by davereap
might this help...
That’s pretty close Dave. I’m going to sketch it out on some graph paper and post it here. I’ll try and get to that tomorrow.
Dec 28, 2019, 10:22 AM
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To eliminate the current nose ballast, could you extend the fuse nose past the disc edge a bit? That would move the motor and components fwd a little.
Dec 28, 2019, 09:26 PM
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I used a 15 g motor and 4 g servos. A 20 g motor and 6 to 9 g servos would probably make the difference without having to move the motor out further.
Dec 28, 2019, 09:45 PM
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Yes, but then you'd own the extra weight. Smaller motor more forward would be the lighter configuration. I'd probably want the bigger motor anyway for outdoor use, but an indoor flyer might want lightest possible.
Dec 28, 2019, 10:24 PM
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Another thought would be for a lightweight indoor version of using 7.5mm EPP. That would reduce the weight behind the CG some also. But really even with the added ballast it still flies very light.

I flew a couple packs on it outside in my front yard today and even with a bit of breeze it flew great. It’s quite the interesting flyer.
Dec 31, 2019, 01:01 AM
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quote 1.." To eliminate the current nose ballast, could you extend the fuse nose past the disc edge a bit? That would move the motor and components fwd a little."..... yes to this idea, which has worked out well..
quote 2..... "I used a 15 g motor and 4 g servos. A 20 g motor and 6 to 9 g servos would probably make the difference without having to move the motor out further."... bigger motor yes, 5gms bigger will give a lot more thrust... bigger servos no, better is a bigger battery moved about to get the COG...

sorry but I had to make some modifications.....lol...yet another version of one of your great designs...

Using the 7-8mm EPP from robotbirds UK
I extended the nose by 1" ..used the 2304-1850 racerstar, which weighs 22gms and has a lot more power, recommended..
servos are TGY1440a from hobbyking , 4.4gms recommended.....with a 12A ESC and a tiny orange 4ch RX.
I use the newer smaller nano-tech 450 size lipos, (high C for helis) ..

weight without lipo 137gms..... with lipo 165gms.... auw 5.8oz.... loading 3.28ozsqft
COG is achieved with the lipo sitting just about on the COG spot.
Last edited by davereap; Jan 06, 2020 at 03:02 AM.
Dec 31, 2019, 06:30 AM
gpw
gpw
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Just an evolutionary statement … We had the usual difficulties with the 25% CG on Round planes , and that evolved into a “FAT" Delta , which provided very “similar" performance , and yet the CG was pushed back to a reasonable level … We lost None of the Aerobatic potential and had a much easier gear distribution . Just saying … We LOVE ROUND Planes , yet there are certain things that make them easier to balance ( like the extra nose length which does no harm , and makes hovering easier .) JMHO
Latest blog entry: Lost plans
Dec 31, 2019, 08:50 AM
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Quote:
Originally Posted by davereap
quote 1.." To eliminate the current nose ballast, could you extend the fuse nose past the disc edge a bit? That would move the motor and components fwd a little."..... yes to this idea, which has worked out well..
quote 2..... "I used a 15 g motor and 4 g servos. A 20 g motor and 6 to 9 g servos would probably make the difference without having to move the motor out further."... bigger motor yes, 5gms bigger will give a lot more thrust... bigger servos no, better is a bigger battery moved about to get the COG...

sorry but I had to make some modifications.....lol...yet another version of one of your great designs...

Using the 7-8mm EPP from robotbirds UK
I extended the nose by 1" ..used the 2304-1850 racerstar, which weighs 22gms and has a lot more power, recommended..
servos are TGY1440a from hobbyking , 4.4gms recommended.....with a 12A ESC and a tiny orange 4ch RX.
I use the newer smaller nano-tech 450 size lipos, (high C for helis) ..

weight without lipo 137gms..... with lipo 165gms.... auw 5.8oz.... loading 3.28ozsqft
COG is achieved with the lipo sitting just about on the COG spot.
Very nicely done Dave and the Disco is really just my take on already proven concepts. But then again that's the fun of scratchbuilding with foam.... you are free to modify/experiment to your hearts content. I agree that I just could have used a larger battery to make CG but I am hoping to get it as light as possible so I'll try again on the next one.
Dec 31, 2019, 08:57 AM
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Quote:
Originally Posted by gpw
Just an evolutionary statement … We had the usual difficulties with the 25% CG on Round planes , and that evolved into a “FAT" Delta , which provided very “similar" performance , and yet the CG was pushed back to a reasonable level … We lost None of the Aerobatic potential and had a much easier gear distribution . Just saying … We LOVE ROUND Planes , yet there are certain things that make them easier to balance ( like the extra nose length which does no harm , and makes hovering easier .) JMHO
No doubt and I do appreciate that a lot of the "heavy lifting" on the concept was already done on the USAF UFO, the Nutball and the PiYak threads.

I still chuckle when I'm zipping around with Disco flying circles around the UMX planes and then it will still slow down and fly slower than them. I piplanes are quite the versatile performers.
Dec 31, 2019, 10:31 AM
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Quote:
Originally Posted by r/cdawg
I agree that I just could have used a larger battery to make CG but I am hoping to get it as light as possible so I'll try again on the next one.
The nose extension should allow you to use your smaller motor, battery and no ballast for less weight. Can anything be done with a foam change? Was looking at a picture of Twisted Hobby's indoor Clik and was amazed at how thin a foam it seems to use. Don't know if it's a stiffer foam or all just carbon magic.


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