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Old Nov 25, 2012, 04:56 PM
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Originally Posted by Tom Z View Post
The entire frame is vibrating when you have no pinion
sounds like your motor bell is out of balance which would cause your vibration.
I have seen some way out of balance and some off just a bit.

See this video.

Bad balanced of my new HP08 motor causes huge vibration of my 4G6.

http://www.youtube.com/watch?v=Mi9JlhM7fJI


Tom
That looks exactly like my problem !

Is it possible to balance the bell of a motor as small as the c05m ? or should i just continue to talk to hobbyking?

Though balancing with tape would most likley not work. There isnt much room around the c05 and the servos/frame on the mini.
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Old Nov 25, 2012, 05:17 PM
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You should be able to balance the C05 motor bell. It will be small to work on though.
There is a how to video I know of that is for the size motor I posted the video on I am trying to find for you. But this will apply to any outrunner motor.

You might want to continue to talk to hobbyking encase you can't balance the bell or the bell is bent.


Tom
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Old Nov 25, 2012, 05:25 PM
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Originally Posted by Xermalk View Post
HK support wanted me to add some tube videos of my vibrating C05M, might as well link them here.

...

8T pinion & 50%/stock gyro. i have to constantly manage the cyclic to prevent it from falling over.

http://www.youtube.com/watch?v=szcA4HOgrNQ
In your last video, it looks like the heli is wanting to tilt left because the AIL Servo/Swashplate is tilted that direction.

I'm thinking either:
  • you either didn't bind/initialize the heli upright on a horizontally level launch surface; therefore the Gyro's didn't sense where "zero" angle reference is, and instead is "locked" in to some off angle?

  • used cyclic (AIL) input before taking off the ground, therefore Gyro's are still trying to do whatever it takes to tilt the heli until the heli actually tilts to that angle (until the AIL is commanded to tilt to an amount equal to the exact opposite angle thereby essentially commanding the heli to go back to the "level" angle again).

  • one of the AIL Servo's have a stripped gear, and the Servo isn't physically able to move to a level position.
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Old Nov 25, 2012, 05:34 PM
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Originally Posted by i812 View Post
It looks like the heli is wanting to tilt left because the AIL Servo/Swashplate is tilted that direction.

I'm thinking either:
  • you either didn't bind/initialize the heli upright on a horizontally level launch surface; therefore the Gyro's didn't sense where "zero" angle reference is, and instead is "locked" in to some off angle?

  • used cyclic (AIL) input before taking off the ground, therefore Gyro's are still trying to do whatever it takes to tilt the heli until the heli actually tilts to that angle or the AIL is commanded to tilt to the opposite angle direction thereby essentially commanding to "level" angle.

  • one of the AIL Servo's have a stripped gear, and the Servo isn't physically able to move to a level position.
Its def the vibrations, as none of those points apply.

The swash actually has a very slight tilt to the right not left, my desk is within 1 degree of being completely leveled and the servos are not stripped (Servo Saver mod & i disassemble the servos after every flight session that involves major crashes).

Anyway im going to continue my discussion with hobbyking, I'm waiting for their reply after having uploaded my youtube vids for them (still amazed that they responded on a Saturday, withing a couple of hours).
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Old Nov 25, 2012, 06:16 PM
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Not to get into a heated argument with you, especially since you probably can see what is happening better than me; however, IMO: vibes normally don't result in a tilting effect. In your videos I don't actually see the heli's body vibrating; however I'm fairly certain I can see the Swashplate is tilted in the same direction as the heli is wanting to tilt. I was going to post that the tilting to the left during take-off is normal (it is); however, it does so with a "level" Swashplate, if the Swash is already tilted in that direction, then I'd imagine in that scenario the take-off tilt would be even greater. I normally don't "diddle" on the ground anymore, and instead take off using a punch and go maneuver quickly accelerating up to altitude within a fraction of a second before really touching the TX cyclic stick. I have difficulty figuring out what is really going on when watching people's videos, because I can't see/determine what is only being done by the heli verses people playing with the sticks. Almost all my troubleshooting is done hands off in a "steady" state.

IMO vibes are caused by a rotating imbalance. A month or so ago, I posted a lengthly description of common out of balance things that can cause rotational imbalance, how to inspect, and how to re-bend/balance. In your second video, it appears as if the silhouette of the rotating Blade Grips are "V"-shaped, if so that indicates severe Blade Tracking error, which would result in severe vibration.

My definition of vibration is a repetitive to and from motion, an oscillation any where from slow frequency to fast. I describe slow frequency (something I can actually see move up and down) as wobble, and vibe as something that is blurry and/or noisy. Either way, I think they are all caused by rotary imbalance; whereas "tilt" is constant lean (not oscillating back and forth). I view vibe and tilt as two separate independent unrelated phenomena.
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Old Nov 25, 2012, 06:59 PM
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The fact that it tilts isnt really the issue though, its the high frequency vibrations through the entire heli frame, even when i have no gear/pinion/tail installed.

That limits it to the motor/bell only.
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Old Nov 25, 2012, 07:26 PM
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Yes

Although I didn't see vibe with the Pinion off. What I saw was a constant same direction motion/rotation. I don't understand why, but I think all mechanically driven rotating things experience a (gyroscopic precession?) force that causes it's rotating axis to tilt off angle with respect to it's non-rotating axis position, and the amount of tilt is dependent on the rpm and amount of weight being turned.

If you say there is Vibe, I'll take your word for it. If so, and it bothers you, then I vote with Tom and would try to balance the Motor's vibe with tape. I've never done a Motor balance, but have seen "before" video showing heli resting on its side vibrating (making noise against the table) and sliding across on the table, and an after video showing elimination of vibration noise and sliding with the strategic placement of a small piece of tape. The author of the video said he used a trial and error method to locate the best placement and size of tape. If I remember correctly, the author dynamically balanced the parts one by one as he assembled the heli from the Motor, Main Gear, Main Shaft, Blade Grips, Main Blades.
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Last edited by i812; Nov 25, 2012 at 08:05 PM. Reason: add last sentence
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Old Nov 25, 2012, 07:39 PM
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Originally Posted by i812 View Post
Yes

Although I didn't see vibe with the Pinion off. What I saw was a constant same direction motion/rotation. I don't understand why, but I think all mechanically driven rotating things experience a (gyroscopic precession?) force that causes it's rotating axis to tilt off angle with respect to it's non-rotating axis position, and the amount of tilt is dependent on the rpm and amount of weight being turned.

If you say there is Vibe, I'll take your word for it. If so, and it bothers you, then I vote with Tom and would try to balance the Motor's vibe with tape. I've never done a Motor balance, but have seen "before" video showing heli resting on its side vibrating (making noise against the table) and sliding across on the table, and an after video showing elimination of vibration noise and sliding with the strategic placement of a small piece of tape. The author of the video said he used a trial and error method to locate the best place and size of tape.
I'm going to see if its possible to do something similar tomorrow, but finding a thin enough tape is going to be hard, there's only at best 1 mm of free space around a c05m mini cp.
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Old Nov 25, 2012, 08:18 PM
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When the Mini first came out, and people first started doing C05 Brushless Mods, some people were experiencing interference problems between the C05 housing and Servo?, and a popular BL mod was to elongate the Motor Mounting Holes in the Main Frame. When WowHobbies first offered their BL Mini, many people complained Wow's hole elongations were too long and made the Main Frame weaker than necessary for the Mod. At the time, besides saving money, many people where preferring to do the mod themselves so they could use the least amount of hole elongation as possible. That was being discussed near the beginning of the year, and I don't think I've read any additional posts about it during the last 6 months.
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Old Nov 27, 2012, 01:34 PM
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I managed to get a refund from HK, and now iv swapped back to the stock motor.

As been flying with vibrations from 2 different c05's for a few weeks now i had completely forgotten how stable the mini actually is, i was shocked when i took it out for a spin today.

I Am going to miss the increased power and almost doubled flight time though.
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Old Dec 07, 2012, 04:19 PM
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Originally Posted by Xermalk View Post
I'm going to see if its possible to do something similar tomorrow, but finding a thin enough tape is going to be hard, there's only at best 1 mm of free space around a c05m mini cp.
Maybe that is why many people that do the BL mod (i.e. use a wider Main Motor) also choose to use the Genius Main Gear? Because Genius Main Gear has more teeth, it has a larger diameter, which positions the Main Motor further away from the Main Shaft, thereby allowing more clearance between Main Motor and Main Shaft?

Its been reported that the Genius Main Gear is a little thinner, has 64 teeth and larger diameter; whereas, the Mini Main Gear is thicker, has 61 teeth and smaller diameter.

If everything else is kept the same, using a Main Gear with more teeth will result in a lower head speed per this equation:

New HeadSpeed = (Old Main Gear tooth count / New Main Gear tooth count) * Old HeadSpeed

If you want to use the larger diameter Genius Main Gear, but don't want the lower head speed, then you can use a larger Pinion to increase the headspeed per this equation (assuming everything else is kept the same):

New HeadSpeed = (New Pinion Gear tooth count / Old Pinion Gear tooth count) * Old HeadSpeed

The combination of both Gears being larger would result in the most clearance between Main Motor and Main Shaft.
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Last edited by i812; Dec 07, 2012 at 04:52 PM. Reason: Add last sentence
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Old Dec 13, 2012, 04:43 PM
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Originally Posted by Tom Z View Post
The pinion is the problem. The Mini CP needs a 0.5M pinion and you have
a 0.4M which the teeth are too close together for the main gear teeth and is causing that noise and less flight time.
I heard gear mesh noise in your videos so that is why I asked what mod pinion you have.

The V120D02S V2 which I have uses the 0.4M pinion. Also the Blade 130X uses the 0.4M pinion.

All you need to do is to get a 0.5M pinion and installed it on your motor. I would also replace the main gear as the teeth will have some wear and or damage on it from the pinion that you have on there now.


Tom
Hi again, I finally got a .05 pinion delivered. So I mounted it all but it behaves awfully strange in that it takes seconds to speed up, it also seems weaker than the factory motor in flight. I made a video of it, basically when I turn on full throttle the motor reacts very very slowly.
20121212 230200 (0 min 30 sec)
That can't be normal can it?

As if that wasn't enough the heli just fell out of the sky on my first try outside, I did a few flips then I lost all control of the tail and the effect seems permanent. Like if the tail gyro didn't work anymore. Anyway I haven't even tried to google that problem yet.
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Old Dec 13, 2012, 07:16 PM
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Hi,

What esc are you using. Some esc's use a slow start feature and that would be normal. I know the XP esc's have the soft start feature if you enable it.
It can take seconds (8 seconds on mine) for the motor speed to build up.
My esc is the Oversky 10A PNP Brusless ESC running the BLheli 6.0 main code. It has an 8 second slow start default setting.

If your using the Walkera esc then that is not normal.
I would check to see that the pinion mesh is not too tight.


Tom
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Old Dec 14, 2012, 04:38 PM
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I'm using a walkera : Walkera Speed Controller for Tail Brushless Motor 10A-LT (HM-4G3-Z-43) from chinese jade

So it shouldn't be normal, and in particular having less power than with the stock motor is quite disappointing. I'm going to give up on this brushless thing, it has just been too long and to difficult, I don't have much energy left to debug this thing and I need to spend that to get my tail gyro to start working again.

In any case, thanks a lot Tom for your knowledgeable advice!
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Old Dec 14, 2012, 06:08 PM
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Hey guys,
I got a question for doing the brushless conversion on my miniCP. Looking at the Walkera speed controller from ChineseJade Item No: HM-4G3-Z-43. It says its for the tail motor does that matter? Looks like it doesn't but I just want to confirm. The other question I had is wiring. It looks like the ESC plugs into the motor spot on the RX and then the battery and brushless motor plug into the ESC. So how does the RX get power? Do we need a splitter to get power to both the RX and ESC? This wasn't included in parts we need but it seems off.
also, if I buy "non walkera" batteries will they charge with my cheap walkera charger that came with my heli?
Thanks!
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Last edited by JStack; Dec 14, 2012 at 06:26 PM.
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