Hovers in a circle. Wtf.

[theRASTAFeARIAN]

My nano has recently been hovering around in a slow steady circle. I constantly have to correct the pitch on the right stick to keep it stable. This doesn't happen every time I fly, but often enough for me to ask you guys how to fix it. HobbyTown said it may be the linkages on my swashplate being 'worn' but I've only had the heli fr like 2-3 weeks. Any thoughts?

It's totally flyable, just not very stable when inverted (mostly because I suck at inverts. Lol) however if I can make that circling motion stop I think I'll have it under complete control.

Thanks guys!

Don C

[Talesin]

Toilet bowl effect, or TBE. Most common cause (so far) on the Nano is over-tightening the feathering shaft. Otherwise it can be caused by parts in the head binding.

[theRASTAFeARIAN]

Originally Posted by Talesin

Toilet bowl effect, or TBE. Most common cause (so far) on the Nano is over-tightening the feathering shaft. Otherwise it can be caused by parts in the head binding.

How tight should the feathering shaft be?

[megawhacker]

Originally Posted by Talesin

Toilet bowl effect, or TBE. Most common cause (so far) on the Nano is over-tightening the feathering shaft. Otherwise it can be caused by parts in the head binding.

Ty. I am not yet in love with my nano. Maybe this will fix. Though I did make an effort not to over tighten.

[mixfisto]

Its tricky with the Nano...its kind of trial and error.

I personally have the best luck with having about a 1mm gap between a grip and the head (when pulling by the blade).

It's also a pain, because you should really threadlock it to keep it from loosening once finding the right tightness. So I would experiment with tightnesses (is that a word), then once finding what works, take the spindle back out, threadlock it, and put it back in at the same tightness.

[theRASTAFeARIAN]

I tried earlier. No success at all :/. Idk what is going on. It literally never used to do this. And now because of it inverts are basically impossible. As soon as I flip her she takes off in a weird direction and so fast that I can't correct it. There is no hover anymore. Just tiny movements.

[tchilds]

Its called toilet bowl effect.

It is 99.9% likely to be a problem with the rotor head. I would rebuild the head and get the feathering spindle straight and proper tension. Clean out your bearings while you have the blade grips apart. You can just spray them out with electronics cleaner. Make sure your shaft isn't cracked, the screws aren't lose on the hub, etc etc

It all needs to be checked if loosening the feathering spindle isn't working. Blade grip tension may be too tight too.

Mess with the rotor head to fix TBE, 99.9% of the time.


If none of this fixes it then clean the servo's. You do not need or want to unplug the servo boards from the main board to clean them, for the nano.


For best performance in a variety of 3d, everything likes to be loose. I prefer no orings on anything except the three lower swash balls connecting to the servo rods. People do this or that and think it flies better but honestly loose as a goose is best across the board for when you're learning 3d or expect more speed/agility than "smoothness".

One last suggestion. It may be your weak boom/worn out tail rotor causing issues during flips and have nothing to do with the toilet bowl during hover caused by a rotor head. The tail motor blows hardest, much much longer and harder, in flips and what not than in hover/standard flight. This brings up issues that aren't apparent in normal flight. An example would be a cracked boom that only twists out of shape in 3d but not in standard flight, or a tail rotor that bends too far when pushed harder by the motor.

[Ric66]

It may also be low rotor speed, likely caused by the main motor going bad. The control response in this situation gets real mushy and the pilot tends to chase the model around trying to keep it in one place. I've noticed mine do this. Even a bad battery can cause similar behavior.

[Talesin]

Originally Posted by theRASTAFeARIAN

How tight should the feathering shaft be?

All trial and error. You want it JUST tight enough that the head doesn't have any in-out play. Possibly just a tiny bit. It's a sweet spot that's about a quarter-turn wide. Too tight, the head binds a little and you get (minimal but noticeable) TBE and chase the heli a LOT more. Too loose and you introduce new vibration into the system, and end up with erratic handling and 'wet dog shake' at random.

Originally Posted by megawhacker

Ty. I am not yet in love with my nano. Maybe this will fix. Though I did make an effort not to over tighten.

I'm not in love with mine. Even after working on it for a good long while, flying it is frankly a chore compared to the mCPX. We can only hope that an aftermarket solution to get the feathering shaft perfectly-tightened will come out at some point.
(And maybe that HH will own up to the fact that the motors they put on are built-to-break, planned-obsolescence trash. Don't hold your breath on that one though, as they still deny the mSRX rudder problem.)

Originally Posted by Ric66

It may also be low rotor speed, likely caused by the main motor going bad. The control response in this situation gets real mushy and the pilot tends to chase the model around trying to keep it in one place. I've noticed mine do this. Even a bad battery can cause similar behavior.

Low rotor speed can cause TBE as well, though it usually also causes erratic/weak cyclic response and 'twitching' first.

[tchilds]

I've got low rotor speed on my old batteries that lvc at 2m and only take 60mah charge at best, also 10h motor. We're talking 30 seconds of 3d to LVC at low low head speed and it never even hits full speed at start.

My nano does not do all that. The only thing it does differently w/brand new cells is I don't have to make one small cyclic adjustment and one tiny rudder adjustment in the exact same way after it goes inverted each time to keep it level. New batteries definitely helps all electric helicopters. I run stock eflite batteries, the new ones are definitely good bats.

The results will be different for everyone what happens when and how. You'll have to just tear it down and fix it, start with the rotor head. You do not need 100% motor to fly the nano for sure though even though high head speeds and efficiency will enhance the nano's ability to compensate for existing issues.

[theRASTAFeARIAN]

I've done all of this. But no luck. When it was new it didn't do this. It just started like 4 flights ago. I tried to invert and landed upside down. Then bam. Toilet bowl effect.

[AWDsylez]

Same issue here. I have to actively keep it in a steady hover, otherwise it goes around in increasingly large circles.

[theRASTAFeARIAN]

Originally Posted by AWDsylez

Same issue here. I have to actively keep it in a steady hover, otherwise it goes around in increasingly large circles.

EXACTY RIGHT! Idk what is the problem. I know the swashplate is level, I just replaced te tailbone 'just incase', and I put the old strait blades on it just because they weren't damaged at all, still. Nothing. EEN tried rebinding it and zeroing out the trim. Nothing.

[megawhacker]

Honestly, I've used my nano less in first 6 months than any other Blade micro I've owned and I had done almost no trouble shooting. Motivated by this thread I did 5 minutes of trouble shooting earlier today and here is what I've found.

I removed the head and found more friction than I think should be normal for the size of the nano moving swash up and down. I moved the blade grips independently and noticed one smooth and one noticeable friction. I loosened the feathering shaft to where there is a slight amount of play and the blade grip friction went away and both blade grips the same.

At this point about half the friction that I consider more than normal is gone. When moving the swash up and down level it seems smooth. When I cant the swash it has noticeable friction going up and down around the main shaft.

I recently moved and have not unpacked or found the 3 in 1 oil. Maybe I'll try canola oil and put it back together.

[Ric66]

Originally Posted by tchilds

I've got low rotor speed on my old batteries that lvc at 2m and only take 60mah charge at best, also 10h motor. We're talking 30 seconds of 3d to LVC at low low head speed and it never even hits full speed at start.

My nano does not do all that. The only thing it does differently w/brand new cells is I don't have to make one small cyclic adjustment and one tiny rudder adjustment in the exact same way after it goes inverted each time to keep it level. New batteries definitely helps all electric helicopters. I run stock eflite batteries, the new ones are definitely good bats.

The results will be different for everyone what happens when and how. You'll have to just tear it down and fix it, start with the rotor head. You do not need 100% motor to fly the nano for sure though even though high head speeds and efficiency will enhance the nano's ability to compensate for existing issues.

Yes, one can certainly learn to fly it with low rotor speed, but it is a little harder. Kind of like learning to turn left on an mSRX, but not quite as hard. BTW, I flew my mSRX the other day and crashed it almost immediately! The nano will make you realize how crappy the mSRX flies!

[theRASTAFeARIAN]

Well guys. Ill try out these tricks in a few days. I know this doesn't belong here. BUT IM GONNA BE A DADDY IN ABOUT 5 HOURS!!!! YAY!!!

Y'all wish us luck.

Thanks for all the advice about my helis so far guys. Can't wait to talk some more about them after my daughter joins the world

Y'all have a great day!!!

[abit late]

Congratulations

- hope all goes well

[theRASTAFeARIAN]

And my daughter is BEAUTIFUL!!!! 8lb 8oz. 18 1/2" little girl.

[Psuedo_Heli_Commander]

Congratulations on the little one!
They don't stay little long... Try to have patience when they're bad and let them know you really care. My little girl, always a daddy's girl, is now 6 months from being 39!
Best wishes to you and your lady.

[tchilds]

Originally Posted by megawhacker

I recently moved and have not unpacked or found the 3 in 1 oil. Maybe I'll try canola oil and put it back together.

Mineral oil will metl and warp your servo' cam/car guides. Use pneumatic oil, sewing machine oil, paintball gun oil, or oil from your hobby store that is plastic safe... 3 in 1 is not and if you've oiled with 3 in 1 you have damaged about $100 in parts. Just go out and buy another nano, reuse what you can.

Getting 3in1 mineral oil on the servo's is about $40 in damage alone.