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Old Aug 19, 2011, 08:32 AM
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Originally Posted by KeljuK View Post
I already changed the flybar and it helped alot. Thnx I put a paper spacers to blade pivots and it stopped the wobble. I'm having a hard time to make left turns at all it likes to stop and just turn on it's place even with full forward and left cyclic...
My Solo Pro 328 does that. Banked left turn is a no go. I seem to recall being able to do this before with it, but after the changes I made, left turns pretty much kills any and all forward speed. My Bravo SX, on the other hand, banks to the left almost just as good as it does to the right. I recall Solo Pro saying he had a similar experience with one of his SXs.
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When flying outside I have to trim it half the way forward and almost full left. Odd. And the bird has been re-kitted :P still the same problems. Maybe i should fix the COG as a stock it's REALLY tail heavy.
Strange that it behaves differently outside than it does inside... The only thing I can think of that would cause that is wind...

Today I shortened the elevator linkage to the max (ten turns) and I tried this after trimming it back to a hover. It was crazy fast going forward but I had zero backward throw left. I went back 5 tuns and it does the job. Much faster forward with a bit less backward throw, but enough for me. I could set it up to have 50/50 forward and backward, but this doesn't do much to help me fight wind... And it's always windy here. So I sacrifice backward throw in favor of forward speed to help me cut through the wind.

I will post videos of the left banked turns outdoor with this heli soon. I'm telling you, it's impressive.

Good luck sorting yours out so that it flies well.
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Old Aug 19, 2011, 09:38 AM
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Originally Posted by bobepine View Post
Strange that it behaves differently outside than it does inside... The only thing I can think of that would cause that is wind...
It's the speed causing the lift to reduce on the other side and the crooked tail makes it worse
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Old Aug 19, 2011, 01:05 PM
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After experimenting with the gyro settings on this heli, I can report that some of the problems some of you are having can be fixed with proper settings. One of the challenges faced by most in doing these settings is the short flight time. This means changing batteries and continuing tests and I don't think this is possible unless you have at least 6 batteries on hand. Another challenge is the motors heating up which means having to let the heli rest for a while.

Me... I have many batteries and I use an air compressor to cool down the motors between each cycles so I can fly with very little interruption when testing this...

I was very careful counting trim input (clicks) because my heli flew well so I didn't want to mess it up. I discovered a few things and maybe this can be helpful to some of you.

While messing with the gyro rate and the main rotor speed, I introduced three problems. All of which were gone once I returned to my original settings. (1)Wobbling, (2)non trimmable tail (heli keeps slowly spinning on itself, losing heading, despite maximum trim even in subtrim mode), and (3)slow gyro rate on left turns making turning left very difficult/slow. These are three issues reported by posters in this thread which I believe are due to poor settings since I introduced all these issues on my heli messing around with the settings. And then I fixed them all by restoring my original settings.

That being said, I know helicopcat reported having tried every gyro setting in subtrim, one or two clicks at the time, with no positive results. Solo Pro reported having troubles trimming the rudder on one heli where maximum trim, even in subtrim mode, would not stop the tail from moving. Well, I think there is more to it than just adjusting the gyro rate in subtrim and adjusting the rudder trim.

I'll give instructions. I will post three different posts subsequent to this one to explain how to solve the above mentioned three issues. I'm off to bed now... I'll explain this better tomorrow.
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Old Aug 19, 2011, 01:13 PM
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Originally Posted by bobepine View Post
I've experienced severe tail boom strikes today and it almost went down... I plan to install a shorter flybar. I ordered some more brass weights today to make custom flybars for this heli. The ones I ordered today are similar to the ones you have except I had them made with a shorter diameter but 3mm longer. I hope they'll be about the same weight or a bit heavier, but smaller in diameter in order to have even more flybar clearance and in order to shorten the flybar a little bit more. I'll post pics when I have that done.

My experience with my bird is much different than yours. I have NONE of your issues aside from the flybar strikes. Mine flies perfectly. I'm especially impressed with the incredibly stable hover and with the banked left turns. I really do feel lucky reading about so many people who have issues with this heli while I'm just thoroughly enjoying mine.
Same here. Mine is still stock, and feels solid in hover, and banked left turns are better than on the Solo Pro.


Quote:
Originally Posted by KeljuK View Post
I already changed the flybar and it helped alot. Thnx I put a paper spacers to blade pivots and it stopped the wobble. I'm having a hard time to make left turns at all it likes to stop and just turn on it's place even with full forward and left cyclic... When flying outside I have to trim it half the way forward and almost full left. Odd. And the bird has been re-kitted :P still the same problems. Maybe i should fix the COG as a stock it's REALLY tail heavy.
I doubt the cog is messing with your left turn ability. Mine is also tail heavy, but like said before, handles very neutral both left and righ turn.


Btw, paper spacer to fix the wobble is a nice idea. Not everyone has the right spacers handy, but paper is always available.
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Old Aug 19, 2011, 01:18 PM
2011 - Year of the clones!!!
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Originally Posted by SoloPro View Post
Btw, paper spacer to fix the wobble is a nice idea. Not everyone has the right spacers handy, but paper is always available.
I agree and will have to give that a try.
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Old Aug 19, 2011, 08:20 PM
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Originally Posted by SoloPro View Post
Same here. Mine is still stock, and feels solid in hover, and banked left turns are better than on the Solo Pro.




I doubt the cog is messing with your left turn ability. Mine is also tail heavy, but like said before, handles very neutral both left and righ turn.


Btw, paper spacer to fix the wobble is a nice idea. Not everyone has the right spacers handy, but paper is always available.
No it doesn't, but forces me to use too much forward trim, which makes it prone to dive radically when making left turns
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Old Aug 20, 2011, 12:27 AM
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Changing Rotor Head Speed~making way for accurate trimming

OK, gentlemen... As mentioned, I found, by fluke, that this heli has one more adjustment that can be made on top of normal trim setting, subtrim settings and gyro settings. This setting is not a stand alone setting in that it has an effect on gyro settings and on rudder trims both in flying mode and subtrim mode.

Look at it this way, on many component based helis, the RX will have cogs to adjust A- the gyro sensitivity, and another one to adjust B- the proportion between tail rotor speed and main motor speed.

By now everyone is familiar with (A) gyro adjustments in subtrim mode. The problem with this is that, just like on any adjustable RX, adjusting the gyro only without adjusting (B) the proportion leaves you with limited program ability.

For the sake of clarity, let's call adjusting A (gyro) and B(proportion) core adjustments and let's call the trim settings for elevator, ailerons and rudder, (both in flight mode or subtrim mode), fine tuning. I will use these terms in subsequent posts.

So... The first thing to do would be to do core adjustments and touch it up with fine tuning the heli with the trim buttons.

Now the question many people who've followed me in this post would like to know is how to adjust (B) the proportion between both motors? Easy... This is done with the throttle trim button in flight mode... In subtrim mode, the throttle button serves as A gyro adjustments, but in flight mode, it serves as B proportion adjustment. It has very little to do with actually increasing throttle or decreasing throttle. And much like the gyro adjustment, 4 or 5 clicks is not much and is hardly noticeable. But 20 clicks, on the other hand, changes the way the heli flies dramatically.

Since normal flight mode limits the amounts of clicks available to the throttle trim button, I think no one has ever noticed the effect of this adjustment and as such it appears to be unknown to the RC community. But there is a very simple way to achieve more clicks on the throttle trim in flight mode. It's done as follows:

1- Bind heli with TX.

2- (Note: Throttle trim down reduces main rotor head speed in proportion with the tail rotor, and throttle trim up increases it.) Let's say we want to decrease it. Press down on the throttle trim all the way to the max.

3- Invoke subtrim and exit subtrim right away. Now you are back in flight mode and your throttle trim is back to the center position.

4- Repeat step 1 to 3 above for additional clicks.

You may need to follow step one to 3, above, at least two times to notice a change in the way the heli flies. The first thing you will notice when you do a test flight is that under your current trim settings, the tail will no longer hold. You will be in dear need of rudder trim to make up for the difference in the rotation speed proportion between the main motor and the tail motor. If the flight trim isn't enough, invoke subtrim and trim the rudder accordingly until the tail holds.

IMPORTANT: Use a pen and paper and note down how many clicks you do when you change the proportion (core adjustments) and also when you trim the rudder (fine tuning). Doing this can easily mess up the programming on your heli and you want to be able to reverse the changes you make if the result is undesirable.
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Old Aug 20, 2011, 12:44 AM
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I cannot trim the rudder even in subtrim

Problem: When I try to trim my bird, I cannot achieve a stable hover. The heli keeps rotating even if I apply maximum rudder trim in subtrim mode.

Diagnosis: X- Main rotor head rotation is set excessively high so the RX can not send enough voltage to the tail motor to hold the tail. Or... Y- Faulty tail motor.

Note that on a new heli, the problem is likely to be X while on used heli, the problem is likely to be Y.

Solutions: X-Reduce the main rotor speed Y-replace tail motor

How to apply solution X

1- Bind heli and TX

2- Press down on the throttle trim button all the way

3- Invoke subtrim mode and try trimming the tail.

4- Exit subtrim mode

5- Repeat the above 4 steps until trimming the tail is successful and the tail holds well. You can even add five or ten clicks more in order to gain a more centered trim range in subtrim mode. By doing this, you will find yourself having to trim the tail (step 3) the other way a little bit. This is good.

Disclaimer: Other problems can cause the above problem, like worn out bearings, hardware interference (rubbing parts), poor COG, worn out main motor, etc. The above repair solution is more so aimed to help people who have trouble with their helis when new and fresh "out of the box." It may also work for seasoned helis, too, though.
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Old Aug 20, 2011, 12:53 AM
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Sounds interesting. But what do you actually change? The ratio of tail rpm to main rpm is already governed by the tail (sub)trim, right? That is what tail trim is for, you increase or decrease the tail rpm to match the torque of the main motor. Seems like this alternate way of adjustment is a little like adding an unbalance with throttle trim, and then fixing it later with tail trim. Almost like first leveling the swash, then trim the heli for stable hover, and find after that the swash has the same angle as before, because it simply needs those angles for stable hover, due to the heli's weight distribution.
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Old Aug 20, 2011, 01:15 AM
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Originally Posted by SoloPro View Post
Sounds interesting. But what do you actually change? The ratio of tail rpm to main rpm is already governed by the tail (sub)trim, right? That is what tail trim is for, you increase or decrease the tail rpm to match the torque of the main motor. Seems like this alternate way of adjustment is a little like adding an unbalance with throttle trim, and then fixing it later with tail trim. Almost like first leveling the swash, then trim the heli for stable hover, and find after that the swash has the same angle as before, because it simply needs those angles for stable hover, due to the heli's weight distribution.
Much like a component based heli, the tail trim is fine tuning while adjusting the proportion on the RX itself is a core adjustment.

You know how when you exit subtrim, your flight trim settings are all back to the center position? Well, not in subtrim mode. Just like the flight trims have a certain range of adjustments and a center position, subtrim adjustments are the same. Subtrim adjustments have a certain range beyond which it doesn't work anymore because you've reached the end of the subtrim range of adjustments.

Well, using the proportion adjustments instead, you can calibrate the subtrim settings for the tail back to the middle of the subtrim range to regain full range on the subtrim tail settings left and right.

Edit: For clarity, let me explain this in different words. When you invoke subtrim and exit subtrim, all your flight trims are back to the center position. Think of the subtrim settings and imagine that they are the same as flight trims with a limited range and a center position. By adjusting the proportion between both motors, this serves as centering or altering the trim settings in subtrim. As such, you can keep a full range of subtrim tail settings left and right.
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Last edited by bobepine; Aug 20, 2011 at 01:21 AM.
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Old Aug 20, 2011, 02:29 AM
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Problem I'm having a hard time to make left turns at all it likes to stop and just turn on it's place even with full forward and left cyclic... When flying outside I have to trim it half the way forward and almost full left

Diagnosis: Since your trim is set to full left, you have little or no more range of motion on the left side making it impossible to use left ailerons to do banked left turns.

Solution: Instead of using trim settings to adjust left ailerons, you need to adjust the length of the servo linkage. In other words, adjust this manually as opposed to using trims. After you're done changing the length of the servo link, enter subtrim and trim to hover. When you do this, observe where the servo sits in it's range of motion. (canopy needs to be removed to see the servo motion). Keep adjusting the linkage manually followed with subtrim until the ailerons servo is dead center in its range of motion when hovering. I would actually set it up so that I have a bit more motion for left turns at the detriment of the right side range of servo motion. About 1mm or less difference.

Regarding speed affecting the heli... How is your pirouette rate? Is left and right comparable or is one side much faster? I think I can help if you answer this question first.
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Last edited by bobepine; Aug 20, 2011 at 06:02 AM.
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Old Aug 20, 2011, 06:34 AM
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Here's a flight video I shot outdoor today. Notice the nice wide left banked turns... Man I LIKE this heli. It's awesome!

Bravo SX Outdoor Flight (4 min 22 sec)


Note: This heli is modded to be a tad faster than the stock version. I will make it even faster but I'm waiting for flybar weights first. Too fast with the stock flybar is a crash waiting to happen...
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Old Aug 20, 2011, 12:36 PM
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Nice flying, at 2:37 for instance is a very nice high speed left turn. Somehow the SX can do this faster than the Solo Pro, without going into death spiral.
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Old Aug 20, 2011, 01:15 PM
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very nice high speed left turn. Somehow the SX can do this faster than the Solo Pro, without going into death spiral.
I agree. It's bloody awesome, meanwhile it also feels very connected like the Solo Pro does. The response is immediate and it really feels like you're in charge of where you want it to go. Not a single flybar strike during that flight, either. I'm impressed. This heli is stock, too. I only adjusted the elevator linkage by 4 turns. On the stock Solo Pro, that flight would have generated at least a few flybar strikes, for sure.

The BSX is quickly becoming my favorite bird. It takes a bit getting used to the heavy tail, I find, but it's staring to click for me... I think a shorter flybar will do it some good, but I'll have to try to see. Despite the rarer flybar strikes compared with the Solo Pro, the strikes still occur sometimes and they feel nasty. In fact, it struck the canopy so hard at one point today that it put in a small crack in the canopy windshield. I can't think of what else could have done that because I have not crashed this heli yet. Not once, which in itself, is a personal record for me with about ten flights on it so far. I should knock on wood...

My friend sells the dark blue canopy... It will be hard to resist buying one on Monday... I don't like the camo look AT ALL.
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Old Aug 20, 2011, 02:03 PM
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I agree. It's bloody awesome, meanwhile it also feels very connected like the Solo Pro does. The response is immediate and it really feels like you're in charge of where you want it to go.
That is what I like about the Solo Pro, and and the SX has it even a little more, I think. This difference was made very clear to me after I flew the GW9958 a few days, and then took out the SX for a flight after flying the 9958. Directly after liff-off the SX was all over the place, because I was way too wild on the sticks, and constantly over-correcting. This took a few seconds, then I realized it wasn't an invisible breeze shaking the heli around, it was me instead. I adapted to it and then I was flying it like I did beofer, thrilled to feel the SX responded so much better to stick commands, and experiencing the very connected feel you describe. It has this feel inside our small living room, but also outside when moving along faster. It's a shame there are some problems with main motor quality on some helis, since apart from that it has no real issues, unless you count the motor noise.
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