HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 24, 2012, 08:48 AM
Registered User
Joined Jan 2012
3 Posts
Help!
Bravo SX Wobble

Hi all!

Total newbie to RC heli's and just bought Nine Eagles Bravo SX. First couple of flights were fine, i then had a small collision and since then I've been getting a wobble on hovering (which seems to be pretty common with SX). Everything looks fine and in its place, nothing broken but I need help getting rid of the dreaded wobble. I've tried trimming but this doesnt help. I saw 'Helicopcat' had posted a solution but as a total novice im not sure where the 'washer' should go and what type of material it should be.

Please help as im dying to get it back to normal


Cheers
Timster19 is offline Find More Posts by Timster19
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 24, 2012, 09:03 AM
Did you check the FAQ already?
SoloProFan's Avatar
The Netherlands
Joined Jul 2010
13,599 Posts
Welcome. A wobble in hover, when not touching the sticks, is not the same as the wobble some have when steering left aileron. In hover the lateral play on the blade pivots is cancelled out by the flybar, but as soon as you give some cyclic command, it appears again. I think you might have a different issue. Maybe a blade pivot was slightly bent, or partially broken off. Also check the flybar, if it's not bent or missing a weight. Although in the latter case, the heli will be close to unflyable...
SoloProFan is offline Find More Posts by SoloProFan
Reply With Quote
Old Jan 24, 2012, 12:17 PM
Registered User
Joined Jan 2012
3 Posts
Thanks for the speedy reply SoloPro

The wobble i have is generally in the hover and when i steer left aileron, however it does become more stable the more cyclic i apply. everthing looks ok to my novice eye. i did notice that when i power up the two rods at the front of the main rotor shaft do vibrate as does the swash but i dont know if this is normal behaviour or not? i did try taking the canopy off but found it to be glued at the windscreen!!
Timster19 is offline Find More Posts by Timster19
Reply With Quote
Old Jan 24, 2012, 12:59 PM
Did you check the FAQ already?
SoloProFan's Avatar
The Netherlands
Joined Jul 2010
13,599 Posts
Quote:
Originally Posted by Timster19 View Post
Thanks for the speedy reply SoloPro

The wobble i have is generally in the hover and when i steer left aileron, however it does become more stable the more cyclic i apply. everthing looks ok to my novice eye. i did notice that when i power up the two rods at the front of the main rotor shaft do vibrate as does the swash but i dont know if this is normal behaviour or not? i did try taking the canopy off but found it to be glued at the windscreen!!
A little vibration is normal. I would suggest trying those washers, in the FAQ thread, on top of the main page of the Micro Helis section there is a picture that shows where to put the washers, and what play these should counter.

Bent blade pivots on the head might also cause some inbalance. If you don't already have a main shaft as spare handy, I would suggest ordering it, and see what happens when you replace the main shaft. Only the top section needs to be replaced, you can leave the CF shaft in place, as it's difficult to remove on the Bravo SX.
SoloProFan is offline Find More Posts by SoloProFan
Reply With Quote
Old Jan 25, 2012, 10:31 PM
Brosol
Brosol's Avatar
Canada
Joined Dec 2010
1,111 Posts
The Xtreme delrin head & Ebay CNC Solo Pro metal head fixed my Bravo SX wobbles & vibration problems. This was after I tried with new NE shaft, head, main gear, rotor, swash....replacements.
Brosol is offline Find More Posts by Brosol
Last edited by Brosol; Jan 26, 2012 at 01:50 AM.
Reply With Quote
Old Jan 26, 2012, 05:34 AM
Registered User
Joined Jan 2012
3 Posts
Thanks for all the help guys. I think i'll try the 'washer' method first and see how it goes. Solo Pro what kind of material did you use for the washer? would paper do the job? ive heard of people using dental floss?!!
Timster19 is offline Find More Posts by Timster19
Reply With Quote
Old Jan 26, 2012, 05:39 AM
Did you check the FAQ already?
SoloProFan's Avatar
The Netherlands
Joined Jul 2010
13,599 Posts
Quote:
Originally Posted by Timster19 View Post
Thanks for all the help guys. I think i'll try the 'washer' method first and see how it goes. Solo Pro what kind of material did you use for the washer? would paper do the job? ive heard of people using dental floss?!!
I have a couple of Xtreme heads, and one came with extra washers. These would be the best option, as these are thin, and not prone to wear. Just for evaluation you could even use paper, I believe some mentioned in the Bravo SX thread.

The Delrin head will surely fix it, as it adresses the problem on 2 sides, the washers reduce lateral play, and the dampened feathering shaft reduces vibrations.
SoloProFan is offline Find More Posts by SoloProFan
Reply With Quote
Old Jan 26, 2012, 11:04 AM
Airplane and Heli Flyer
V-Man's Avatar
Canada, QC, Montreal
Joined Dec 2009
1,719 Posts
It's a common issue, it seems. My Bravo SX has developed a severe wobble in the last few flights. I've tried the washers solution, which helped a bit at first, but not anymore. No wobble when control inputs are applied, only in hover.

It definitely looks like something is out of balance. I haven't had the time yet to take the heli apart (and considering the full fuselage, not looking forward to it!), but I suspect the blade pivots. Will probably change the head for the Delrin one, since a lot of people have had good experience with it. Just need to find a place that sells it and has it in stock...
V-Man is offline Find More Posts by V-Man
Reply With Quote
Old Jan 26, 2012, 04:07 PM
Registered User
United Kingdom, Oxted
Joined Dec 2011
426 Posts
I've not enjoyed either the Solo Pro or the Bravo if I'm honest. I've had three pros and one Bravo and none of them were right. Don't ask why I replaced them!!!!

The first Pro - not set up anywhere near correct. Take off was horrific. Broke two sets of skids trying to land it in one piece. Gave it away to someone who could be bothered.

2nd Pro was set up but horrific wobble. I also found the transmitter to be very crude.

The Bravo - wobble. Still suffered from a crude transmitter. Gave up.

3rd Solo Pro - wobble. Yawing different ways. Still suffering with crude transmitter. The flybar seemed to have 'magnetic' control of its flight. Go forward three feet and backwards two when you stopped. I gave up again.

So I haven't had good experiences with the Nine Eagles and kept going back because some 'good fliers' were recommending them. I haven't really been happy with any of them.

Part of it is the transmitter though. I really don't like it.
iancraig10 is offline Find More Posts by iancraig10
Reply With Quote
Old Jan 26, 2012, 04:28 PM
Airplane and Heli Flyer
V-Man's Avatar
Canada, QC, Montreal
Joined Dec 2009
1,719 Posts
Quote:
Originally Posted by iancraig10 View Post
Part of it is the transmitter though. I really don't like it.
I'm not a huge fan myself. I wish NE would come out with a more advanced version of their full-size Tx, the J6, that would include multi-model memory. That way I could sell off all my "breadbox" basic NE Tx and get something that can be adjusted.

Oh, for some way to add expo to the sticks...
V-Man is offline Find More Posts by V-Man
Reply With Quote
Old Jan 26, 2012, 04:37 PM
Registered User
United Kingdom, Oxted
Joined Dec 2011
426 Posts
Quote:
Originally Posted by V-Man View Post
I'm not a huge fan myself. I wish NE would come out with a more advanced version of their full-size Tx, the J6, that would include multi-model memory. That way I could sell off all my "breadbox" basic NE Tx and get something that can be adjusted.

Oh, for some way to add expo to the sticks...
Exactly!! They supplied sub-trim but not expo!! Maybe my experiences with them are not typical, but after the attitude shown towards me by the seller of them and the problems that I had, I decided to give up on them.

To me, they seemed like a cheap heli that wasn't really set up properly and just not for me.

However, I know a guy who swears by them and loves them to death and I respect that.
iancraig10 is offline Find More Posts by iancraig10
Reply With Quote
Old Feb 04, 2012, 06:15 AM
Did you check the FAQ already?
SoloProFan's Avatar
The Netherlands
Joined Jul 2010
13,599 Posts
Quote:
Originally Posted by iancraig10 View Post
Exactly!! They supplied sub-trim but not expo!! Maybe my experiences with them are not typical, but after the attitude shown towards me by the seller of them and the problems that I had, I decided to give up on them.

To me, they seemed like a cheap heli that wasn't really set up properly and just not for me.

However, I know a guy who swears by them and loves them to death and I respect that.
Hope you don't mean me, I like my helis to live and fly.

The experience depends a lot on the first moments out of the box. The different behavior when giving rudder, making the heli shoot forward or backward, can be very off-putting, when coming from a coaxial for instance. I returned my first Solo Pro and got a coax version instead, as I deemed the SP unflyable because of this. I thought I would never be able to learn to anticipate this rudder behavior. The mSR uses onboard mixes to camouflage this behavior. While a beginner may appreciate that, later on this same mix limits flight somewhat, and most advanced mSR pilots have tried to apply a counter mix with the Dx6 or Dx7 to remove this mix.

Needless to say, later on I decided to have a go at the SP again, and still had trouble with the rudder response. Only when I took it outside on a windless day, with room to see how the heli behaves on rudder input only (inside there was always a wall or piece of furniture in the wat), was I able to grasp the way this heli handles, and now the needed elevator correction for a rudder turn "on the spot" comes natural.

Also, quality control seems to have dropped a little lately, with more receiver problems, like servos not responding, and if you get this on your first heli, you will be disappointed, if the second heli has an issue you will be mad, and if the third ones breaks, it will be a PoS no doubt.

Sadly, this slacking off on quality control seems to be universal, even brands with a rock solid reputation (Toyota anyone?) have made major mistakes. Remember the Trex100s. I think if I had to pay a dollar for each pilot that has one that is flying satisfactory, I might even receive money, instead of having to pay... Yet the Trex100s was over twice the price of the Solo Pro at first...

I agree, nowadays it's a gamble to get a good heli the first time, whether it be Nine Eagles, or other brands. But the problem is usually not a design error, but the execution at mass production, that leaves to be desired.
SoloProFan is offline Find More Posts by SoloProFan
Reply With Quote
Old Feb 04, 2012, 06:26 AM
Registered User
United Kingdom, Oxted
Joined Dec 2011
426 Posts
No, SoloPro I don't mean you at all!! I'm coming from a 450, MCPx, MSRx - the other side of fp flybar helis so for me it was a bit of a diversion.

Actually, I was curious because I have a couple of friends; one who is very experienced who swear by the solo pro. I got one just to see how near the old MSR it was. It was awful. Shot all over the place and wobbled. I sent it to one of the friends who gave it to the experienced guy to look at - he found set up faults so he fixed it and I'd lost interest so I told the other guy he could keep it.

Then stupidly - I got another. Again it was mad. I didn't even bother.

Even more stupidly, I got an SX. Awful. Wobbled all over the place but flew better than the two pros I had.

Got another Pro recently - just the same.

After that, I gave up.

I agree, that they hover unbelievably easily. I don't like the sudden halts that they do when you let go of the stick and the 'bucking about' it does on fast forward.

However, it's fun but for me, just not in the same league as the Blade MSR of old and way behind the MSRx.

Nice starter and cheap as well, but not for me really. I think you're right - mass production and quality control may have suffered which is not good for Nine Eagles because it has made me very wary of the brand because the Pro and SX seem to fly so crudely. (I also hate the transmitter)

Anyway, I wasn't trying to have a go at anyone ..... honest.
iancraig10 is offline Find More Posts by iancraig10
Last edited by iancraig10; Feb 04, 2012 at 06:45 AM.
Reply With Quote
Old Feb 04, 2012, 07:23 AM
Did you check the FAQ already?
SoloProFan's Avatar
The Netherlands
Joined Jul 2010
13,599 Posts
Ah, you took the reverse route. In that case I think no 45 degree flybar will feel really comfortable, as every design has some unwanted traits. To a certain degree, a 45 degree setup will try to correct the pilot, whether he needs that correction, or not.

As for the TX, you either hate it or love it, it seems. I like that it offers almost the same options as a much more expensive TX, like EPA, subtrim, gyro adjust and good indication of trim and throttle on the display. Compare that to the 2 leds you get on the mSR RTF TX with the beeps supposed to indicate the trim setting, and the mSR TX will loose on all aspects. But I know better sticks, and additional settings, like throttle curves and expo will make a big difference. I have an old Robbe Starion transmitter, and the stick feel on that is much more refined. NE should indeed focus on making a TX like the DX6i, to provide a "step up" option for control. The RTF TX is not bad, but a better TX will enhance flight experience, no doubt.

As for the wobble, the Xtreme delrin head, with dampened feathering shaft, usually takes care of that. A good stock head should also be wobble free for a while, but as parts wear, it will return, and the dampers can fix that. The new Solo Pro, the 270, has these dampers, so NE must have realized there was a problem.
SoloProFan is offline Find More Posts by SoloProFan
Reply With Quote
Old Feb 04, 2012, 08:03 AM
Registered User
United Kingdom, Oxted
Joined Dec 2011
426 Posts
Quote:
Originally Posted by SoloPro View Post
Ah, you took the reverse route. In that case I think no 45 degree flybar will feel really comfortable, as every design has some unwanted traits. To a certain degree, a 45 degree setup will try to correct the pilot, whether he needs that correction, or not.

The new Solo Pro, the 270, has these dampers, so NE must have realized there was a problem.
I agree about the Blade transmitter. It is a bit crude to say the least. What I don't like about some of the rtf packages they do - the transmitter is the weak link. Selling the MCPx with a DX4e is a bit naff really. You really need to adjust the settings to get it to fly nicely so it's no wonder when I spoke to a hobby shop guy here in the UK, he said that he was doing really well out of MCPx spare!!! He also blames the transmitter for the problems, but he certainly ain't complaining!!

The Solo Pro would be nice with a smoother transmitter as well for me. I had no problems flying it outside (so respect in that case) It's just there's no room for little tweaks. For instance, move the trim once - nothing happens, may be twice, nothing happens and on the third, it's too much and so you end up trimming backwards and forwards.

There's a lot of play so it's hard to get it to fly as smoothly as I like, but then again, maybe I expect too much from such a cheap little micro.
iancraig10 is offline Find More Posts by iancraig10
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Nine Eagles Solo Pro / Bravo SX brushless conversion thecubist Micro Helis 46 Mar 21, 2012 11:57 AM
Sold BRAVO SX planes. RTF, BNF, OMG. SoupInMyCoupe Aircraft - Electric - Micro & Indoor Airplanes (FS/W) 17 Oct 03, 2011 09:29 AM
Sold Solo Pro/Bravo SX Aluminium Parts (swash, collar, main shaft and rotor head) bobepine Aircraft - Electric - Helis (FS/W) 1 Sep 07, 2011 09:10 PM
Wanted 4Ch Bravo III, 5888, F27, Bravo SX Brosol Aircraft - Electric - Helis (FS/W) 0 Apr 14, 2011 07:47 PM
Discussion Differences between Bravo III and Bravo SX bunger Coaxial Helicopters 5 Jan 15, 2011 03:40 AM