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Old Oct 08, 2012, 03:23 PM
Brent 黑雁
BThirsk's Avatar
Canada, AB, Ponoka
Joined Jan 2012
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Originally Posted by Stoersender View Post
That looks pretty damn good!

Did you use 450 or 250 paddles?
Everything is Trex 450, both the weights and the paddles. The strange thing is the combined weight of the paddles and the 2 additional weights is almost the same as the original flybar weights. The only difference is the paddles try to keep the flybar in a stable plain and resist moving to a new plain, which seems to allow the swash movement to be more effective in changing the pitch movement and the flybar does not totally dampen the effect as with the stock flybar.
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Old Oct 08, 2012, 04:34 PM
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Joined Jul 2012
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My flybar is still good , but after some crash i see that it slightyl bent a bit . But i did make a lot of vibration . So i have order another flybar to replace . But my question is any idea to mod the flybar ? better and stabile in the air ?
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Old Oct 08, 2012, 04:40 PM
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United States, SC, Irmo
Joined Sep 2011
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Originally Posted by BThirsk View Post
Everything is Trex 450, both the weights and the paddles. The strange thing is the combined weight of the paddles and the 2 additional weights is almost the same as the original flybar weights. The only difference is the paddles try to keep the flybar in a stable plain and resist moving to a new plain, which seems to allow the swash movement to be more effective in changing the pitch movement and the flybar does not totally dampen the effect as with the stock flybar.
That would INCREASE damping I think. The flybar staying where it is - is what does the damping. Lightening it makes it change plane faster, reducing damping.
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Old Oct 08, 2012, 05:01 PM
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United States, CA, Modesto
Joined Aug 2012
828 Posts
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Originally Posted by BThirsk View Post
Did you check for enough clearance on the bottom of the hoops with your addition. The ball links come very close to the hoops as it is when you apply Full AIL and ELV at the same time.
I think that is a possible cause of the hoops breaking on some units where the Ball link actually pushes on the hoop.
I will look at that when I get home.
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Old Oct 08, 2012, 05:01 PM
John
Australia, QLD, Brisbane
Joined Aug 2012
542 Posts
noname2x -
The purpose of modifying the flybar is (as I understand it) to REDUCE stability, and increase performance. I am trying something along these lines - nothing as advanced as BThirsk, though.
But I'd really like a dollar for every time I've had to straighten (and reuse, of course) the flybar! - always good to have a spare, but so far (touch wood) have not needed one. In fact, haven't used anything but motors and tail assemblies out of the box of spares I got with the first F45.
- John.
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Old Oct 08, 2012, 05:46 PM
Brent 黑雁
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Canada, AB, Ponoka
Joined Jan 2012
1,781 Posts
Quote:
Originally Posted by shahram72 View Post
That would INCREASE damping I think. The flybar staying where it is - is what does the damping. Lightening it makes it change plane faster, reducing damping.
Watch the flybar when you are hovering and give a full jab of right cyclic. The heli jumps with authority for about 1 second until the fly bar overcomes the new position and settles back to where it finds the best center of rotation causing the heli to lose this authority and self stabilize to a certain extent. I have about the same weight, but the paddles seems to allow the movement to effect the blade pitch and because they are wings, they try to maintain a flight path and do not self stabilize as fast as just the weights thereby not reducing the authority derived from your swash position.
Adding more weight does dampen the effect. With only one weight and at 100% on the sticks, the cyclic was harder to handle than my 450CP, which is also a flybar heli.
With 2 weights, total weight similar to the stock flybar, and cyclic set at 80% in the tx, it is now manageable and does self stabilize to a certain degree.
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Old Oct 10, 2012, 04:10 AM
when is the wind stopping??
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Malta, Marsaskala
Joined Apr 2011
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Quote:
Originally Posted by BThirsk View Post
This is a short inside test of my new flybar mod. It is fairly easy to handle now.
http://youtu.be/_njO6pgRtlI

Some pictures below of the flybar system and the swashplate.
Good job Bthirsk I like the flybar mod a lot
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Old Oct 10, 2012, 05:20 AM
Brent 黑雁
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Canada, AB, Ponoka
Joined Jan 2012
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Originally Posted by markkona View Post
Good job Bthirsk I like the flybar mod a lot
Thanks.
I finally got a break in the weather and got it out last night for a short fly.
The response on the sticks is quite different now. When doing a banked turn, I only need a slight touch of AIL instead of 100% that I am used to. It's the same with the ELV. You only need a little ELV and you are moving quite fast and need to compensate with the throttle to maintain altitude. I only had it up to about 75 feet so I could fly about the trees, but it is manageable.

This will be a whole new learning experience to get away from over correcting. And now I really don't like the TX. After using the Devo or the Turnigy TX, this one has very little feel.
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Old Oct 10, 2012, 07:00 AM
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United States, FL, Hernando
Joined Sep 2012
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With the Tx, what I did was open it up and filed down the notchs on the throttle side and tightened the springs on both sides. Although the Tx still feels like a toy compared to the Dx6i, it now has a better stick feel.
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Old Oct 10, 2012, 07:18 AM
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Germany, BW, Göppingen
Joined Aug 2012
70 Posts
damm.... today I installed the modded tail to go brushless...
problem so far: the tail isn't really able to keep up with the main rotor. It's not able to counteract the rotation at all :/

strange thing is:
when I try to run the tail motor at full speed it sort of dies after 5sec and just stops...

any ideas? is the brush to brushless converter crap?

is this the FET problem, discussed 2 pages back?
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Last edited by Stoersender; Oct 10, 2012 at 07:28 AM.
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Old Oct 10, 2012, 07:52 AM
Micro Heli mods
Tumppi T's Avatar
Finland, Tuusula
Joined Mar 2012
181 Posts
Quote:
Originally Posted by Stoersender View Post
damm.... today I installed the modded tail to go brushless...
problem so far: the tail isn't really able to keep up with the main rotor. It's not able to counteract the rotation at all :/

strange thing is:
when I try to run the tail motor at full speed it sort of dies after 5sec and just stops...

any ideas? is the brush to brushless converter crap?

is this the FET problem, discussed 2 pages back?
....yes...that is the same problem I faced. I changed the FET and now it functions well. My tail prop is DH9104:s original one
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Old Oct 10, 2012, 08:02 AM
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Germany, BW, Göppingen
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Originally Posted by Tumppi T View Post
....yes...that is the same problem I faced. I changed the FET and now it functions well. My tail prop is DH9104:s original one
Can you make a photo of how you changed it? Where it's placed on the PCB? I'm not a big electronics geek and it would be very helpful

What specs should the replacment mosfet have?
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Old Oct 10, 2012, 12:14 PM
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Germany, BW, Göppingen
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Is this the FET I'll have to change?



The replacement needs at least 16A or exactly 16A?
Does the Voltage has to 60V or is it also possible to use one that says 300V?

I'm really sorry, but I hate electronics
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Old Oct 10, 2012, 12:32 PM
Brent 黑雁
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Canada, AB, Ponoka
Joined Jan 2012
1,781 Posts
Quote:
Originally Posted by Stoersender View Post
Is this the FET I'll have to change?



The replacement needs at least 16A or exactly 16A?
Does the Voltage has to 60V or is it also possible to use one that says 300V?

I'm really sorry, but I hate electronics
I am confused. Are you running a separate ESC for the tail motor? If so, that ESC should supply the tail motor power and the PCB has nothing to do with the power source as far I as I know. Again, I am not that electriclly inclinded.
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Old Oct 10, 2012, 12:49 PM
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Germany, BW, Göppingen
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Quote:
Originally Posted by BThirsk View Post
I am confused. Are you running a separate ESC for the tail motor? If so, that ESC should supply the tail motor power and the PCB has nothing to do with the power source as far I as I know. Again, I am not that electriclly inclinded.
The ESC runs serperatly...
But the brush-to-brushless converter uses the original tail motor's jack on the pcb.
The converter is used to "translate" the brushed signal for a brushless motor.


Then the ESC is plugged into the converter.

Tumppi T is using the exact same converter as I do. And he had to change the FET.
Maybe the converter needs more amps than the original FET can supply... or something.

But I'm no expert, too
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