Help!: Our Nutball will not fly....

dmanmtl

Junior Member
ok, so my son and I have spent many hours building a nutball. We followed the plans from FT pretty closely, the only extra we have on the plane is some tape to color the wing tips. Our electronics/power are as follows:

8x4 Propellers
Turnigy 500mAh 2S 20C Lipo Pack
hexTronik 24gram Brushless Outrunner 1700kv
Hobbyking SS Series 25-30A ESC

Due to some back orders at hobbyking I chose a different motor than the original spec, I assumed this motor would simply be more powerful.

Basically, the plane seems very under powered, it will drive around the field like a car, gets off the ground for a second or two but cannot hold anymore than 10 inches of altitude.

We have a Turnigy 9X and I have a feeling there is an issue with the throttle communicating with the ESC. I have tried several times to re-calibrate the ESC using the technique described by Josh Bixler in the video but still the throttle needs to be movedup to almost 50% before the motor start to turn. I have a feeling I may only be getting 50% power out of the motor which could explain why the plane will not fly.

FYI: I have also tried the Turnigy stick calibration process...no change.

Any advice would be appreciated! Do I have the wrong motor, wrong ESC or some sort of calibration problem...

DM
 

MrClean

Well-known member
And your CG is where?

Also, a couple pictures would be nice, just so we can see your creation. 2 cell 20 C 500 mah packs aren't very strong or heavy.
 

FlyingMonkey

Bought Another Trailer
Staff member
Admin
Your propeller is on backwards.

The numbers on the propeller that tells what size it is, needs to be on the front.
 

earthsciteach

Moderator
Moderator
Welcome to the wonderful world of rc aircraft! Even with so much info available on the internet, there is so much that is simply trial and error, particularly with a programmable radio.

The 8x4 prop seems like its ok with that motor. I initially thought the 2 cell battery was too little, but the motor seems to be ok with a 2 cell.

I'm guessing, barring a backward prop, that you need to play around with your throttle settings in the radio. If you must raise the throttle to 50% before the motor spins, something isn't set correctly. I wish I could tell you exactly what to do, but in these situations, I just play around with settings until it works out.
 

pgerts

Old age member
Mentor
Under power seems like it.
Driving around lika a car - tells that you have an under carriage - the plane is heavy for a 24 gram motor. The total weigt should not be much more than 200-250 grams.
The battery looses a lot of initial voltage the first 30 seconds.
You might get a little better power with a 3 cell 800 mAh battery for outdoor use.
It is possible that the propeller with a 3 cell might be exchanged for a 7".
 

SteveRoby

New member
"still the throttle needs to be moved up to almost 50% before the motor start to turn"
This is your problem .

The throttle MUST be all the way down when you turn on the radio & connect batt to plane.If not it could screw up esc calibration (unlikely, but possible)
Also make sure the throttle trim is all the way down(not centred)

My nutball flys with that same setup( but the lesser 1300kv motor). Enough power to hover
I very much doubt you need to calibrate a HK esc, I havnt needed to on my many planes, in fact I dont even bother now (I probably should)

More likely you need to setup/fix the transmitter, perhaps its in heli mode ?? Is the transmiter software setup in mode1 or mode2 to match what mode the hardware is ??
Perhaps reset the transmitter & start again. There are plenty of youtube vids with the basic setup.

Also, whats the weight of you plane, all up incl battery?
The nutball should have more than enough power to take off without a run up, straight out of your hand, thats how I launched mine.
Possibly not a wise choice of plane for a beginner, not the most stable/easiest (my opinion), but that makes it lots of fun.

Which 8x4 prop are you using, some are very heavy, perhaps too heavy for that motor.
 

Onebladeprop

New member
The throttle not working until it's past 50% is definitely atleast part of your issue. Did you program the transmitter in ACRO or did you accidentally set it up in heli or something? If you're still having trouble you might make a video showing your settings, plane, ect, upload it to youtube and post the link here. Maybe someone will catch something you overlooked. That motor will have plenty of power for a nutball so it should work. It's most likely just a small detail you've overlooked.
 

dmanmtl

Junior Member
Guys, Thanks for all your replies - I was under the impression that no one had replied as the "replies" field on the previous page showed zero...strange.

The prop is not on backwards (smart enough to figure that out ;) - the planes runs around great in what my son calls "car mode"

I am sure I am not getting max thrust due to the transmitter issue - I am going to set it up with the trx and rx from one of our other planes to see if that does the trick. I have tried calibrating the ESC several times and followed the instruction to a T.

Will report back if I get this fixed!

Thanks for all your replies!
D
 

FlyingMonkey

Bought Another Trailer
Staff member
Admin
The prop is not on backwards (smart enough to figure that out ;) - the planes runs around great in what my son calls "car mode"

I assure you, intelligence is not a factor... I doubt there's many rc pilots that haven't tossed a plane into the air, only to have it "land" soon after due to putting the prop on backwards.

It will taxi, and almost lift off, but that's about it.