Trex 450 Blade/Tracking problem

[hsa5006]

I have a problem with my Trex 450, I have exchanged my broken stock rotor head and ever since that build I have been having this exact same issue.

Whenever I increase the throttle the Heli always pitches forward, almost damaging the blades, only thing saving my blades are the training gears.

Can someone help diagnose this problem? I will be forever so grateful
:)

Watch here (Sound interference please mute youtube)
http://www.youtube.com/watch?v=OR3su8b_fSc

[John Cook]

improper setup either CCPM isn't acting right, or you are way way out of trim or balance.

Go through the Finless bob build videos for that heli and see if you can track it down

[hsa5006]

Thanks I will give it a shot and throw back with questions if i need to inquire about anything else

[hsa5006]

Can someone check/confirm if my cyclic controls and pitch spot on when controlling my servos please??

http://www.youtube.com/watch?v=8IaB6hJ72JU

I also leveled the swash plate using the leveling tool

[John Cook]

looks good to me

I've had a few beers though tonight so maybe wait for a 2nd opinion hehe!

[gyroimunav]

Swash and thus servo movement seem to be correct based on your input check video. Swash does seem to move up/down only on throttle up which is correct. Must be an aerodynamic problem, mechanical seems fine! If you take the main blades off and repeat your first video, look closely at the head and swash..spool up motor..swash should move up and down, head should not vibrate or wobble...(only minor vibs)..Could be blades or interaction with head and blades..The reason it is pitching is something is causing the disk to tilt.

[gyroimunav]

General advice: When you find a problem..start with the obvious and go backwards. Disk is tilting on throttle up...what causes the disk to tilt, those functions have to be somehow related to the throttle input..First video is hard to see what the head is doing

[hsa5006]

No matter how I turn the rudder the heli will keep spinning.

If i turn the rudder left it will keep spinning faster to the left

Turning the rudder to the right will initially stop the heli from spinning when floating, but when hovering the helo will keep spinning to the left still

Can someone help please??

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

[gyroimunav]

Your not getting any torque from the tail. The gyro should be driving the servo to arrest the yaw from the head. Could be gyro, servo or something mechanical. Do this test...make sure the tail pitch slider moves toward the correct side when..

A. Tail moves without TX input(gyro induced pitch control)
B. You give left and right yaw inputs to the stick.

If those two tests are done are it works, then it could be your gyro gain is not set high enough. You said that right rudder(noise right) input did slow the CCW yaw rate down which indicates to me that your controls are setup good. I would check gyro settings.

[gyroimunav]

Did you fix the disk tilt problem?

[hsa5006]

Yeah I believe the disk is correctly assembled now, I do get lift when I want to..
with non of the involuntary pitch..

[hsa5006]

Please mind you that I have the FMA Copilot II system installed, and I believe the Gyro also passes thru the computer.. I dunno if this has any relevance in the problem

[gyroimunav]

Oh Yeah, I would take that thing off and conduct your experiment again. I agree that could be affecting your yaw..If the gyro passes through there before it goes to servo, the it could be messing with it

[hsa5006]

Shifting the position of the gyro's servo resulted in the following:

http://www.youtube.com/watch?v=l3tRi6RYCMY

Which is an improvement to what my heli acted like before, but still needs some work, maybe someone can throw me suggestions?

Thanks

[hsa5006]

I have done all of what you guys suggested but I still yet to see any results, the heli still drifts or spins out of control..
I dont seem to be getting full movement, even with following Bob's videos to the letter..

This is a video of what happens at my tail (I do get movement with the TX / ie gyro control ie it works)

http://www.youtube.com/watch?v=6-O3ScnzZ1U

Maybe it does have something to do with Gyro gain, but I cannot change gyro gain on my tx, im using an exceed rc 2.4 Ghz, with no electronic controls like the radios used in the videos shown..

[hsa5006]

I flipped the belt, it runs very smooth when I use my finger to rotate the main blades,

I hear a very faint rubbing noise, like the belt's teeth meet at some point, dunno how worried I should be about that..

Anyway, just ran into another problem while handling this one* :(
Seems like every time i do something I run into another problem its getting frustrating honestly..

When disconnecting the motor wire, one of the leads just popped out, seems like it was loose from before, any idea how to fix this?
PLEASE SEE THE SELF EXPLANATORY ATTACHED PICTURES

http://www.flickr.com/photos/51273903@N07/4712465437/
http://www.flickr.com/photos/51273903@N07/4712465133/


Btw I had time for a quick hover test before removing the motor cable this was what happened

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

[gyroimunav]

Hang in there man, we'll get you fixed up. The motor connector just needs to be soldered back on. You can buy a soldering gun from walmart, lowes..almost anywhere. I would invest in one. Very handy.

For the tail, something doesn't seem right with your controls. When you move throttle stick left and right, it should change the pitch of the blades both ways. Make slow inputs left and right and verify that tail rotors pitch proportional to your inputs..Then you need to turn on the heli(with motor disconnected) and swing the tail around manually. Verify that the gyro is working by observing the tail rotor should change pitch. If you are in HH mode, when you move the tail and stop the rotors will change pitch and stop..When you are in rate mode, the tails rotors should change pitch and go back to netural. What kind of gyro are you using. I had problems with my exceed gyro a while back. Bought a GY401..No more problems

[qhent]

Not trying to be a nit but.... I used to own an ExceedRC BlueRay so I am a little familiar with the transmitter. The knob just above the rudder/throttle control stick side of the transmitter is normally the gyro gain control. The tail blade non-response is because you were in heading-hold mode (less than 50%). Adjust the knob until you are in rate mode (more than 50%).

BTW, you really need the cable and software to set up your transmitter. It is a pain in the butt, however, it works if you are patient and willing to spend a lot of time spooling up, testing the setup, spooling down, connecting the radio to the computer and starting the process all over again. I dumped the ExceedRC transmitter and receiver and went with a Spektrum DX7...and have had a blast ever since.

Hope the info helps. Have an OUTSTANDING day!

P.S. Stay with it. R/C helis rock!

[not1b4me]

I have done all of what you guys suggested but I still yet to see any results, the heli still drifts or spins out of control..
I dont seem to be getting full movement, even with following Bob's videos to the letter..

This is a video of what happens at my tail (I do get movement with the TX / ie gyro control ie it works)

http://www.youtube.com/watch?v=6-O3ScnzZ1U

Maybe it does have something to do with Gyro gain, but I cannot change gyro gain on my tx, im using an exceed rc 2.4 Ghz, with no electronic controls like the radios used in the videos shown..

Looks like the tail blades are on backwards. thick part of blades rotates up thru downwash of main blades...

[gyroimunav]

+1 backwards..That should at least generate the proper thrust on the tail..The setup and gain will be next because you have probably changed all that to get'er right

[sagrzmnky]

Was this problem ever solved? I agree with not1b4me. One of the tail rotor blades was on backwards.