Wobbles

[kd7jkt]

I noticed an odd thing after I installed a new Spektrum DX7 system in my Trex450SE V2. A short flight test (just a few seconds) showed an odd wobble in hover. Think of a dish spinning on a stick. I could hear the tail trying to correct this. I had also replaced the Main shaft and the Feathering shaft.
I'm stumped, any ideas?

[darkchiild]

The only time I've ever seen wobble like that is when the blades are out of track. I'd check that.

[Skiddz]

Wobble is typically low headspeed related. What motor/pinion, what batteries and what are your pitch/throttle curves?

[kd7jkt]

Thanks, I'll look at that. They were in track, but I should have figured out that when I replaced the feathering shaft which was slightly bent with a new one it might have changed the blade adjustments.

[kd7jkt]

Thanks, I'm going to take the heli and new radio to a local expert next week and have him go over the setup with me. I did lower the pitch curve on the new radio a bit but I'm still a newbie and will have this gent show me the correct settings.

[kd7jkt]

The problem was both low headspeed and tracking. My local expert went thru my ship from end to end and showed me where I had gone astray. He also set up my DX7 for me and showed me what to do next time. I'm glad I bought the heli there as these services come free to all their customers. Thanks for the input, it gave me something to tell them as a starting point.

Thank you

Jim (kd7jkt)
Blade CX2, Trex 450SE V2, all stock.

[flipped]

Hello, flipped here, I had a wobble problem with my TREX recently and I had no idea what the problem was. after I destroyied a great set of carbon blades on a fence post that moved in the way, lol. I replaced the feathering spindle and the main shaft. to be safe. and a new sset of main rotors of a different brand. set the tracking and found the wobble when I hovered the chopper. I cheched every thing in the rotor head, changed tail shaft thinking that may be it but the wobble was still there. I noticed I had tieghtened the main blade in the blade grips to tight. after loosening the grips a little so the blades would move with little resistance. the wobble was gone.hope this makes sence, and helps, have fun flying and be safe.

[kd7jkt]

A little backstory on this problem. I had never noticed such a wobble before as I was learning to fly the Trex. About a month ago I was doing some practicing in my backyard and landed to make a brief adjustment to the tail. As I lifted off again, I was subject to an "uncommanded" throttle input which instantly rocketed the heli into a large Douglas Fir tree. (I had been having glitch trouble with the radio system before.) After the bird fell to the ground, I was able to pull the power plug before the pinion chewed entirely thru the main gear. I then replaced the main shaft, the feathering shaft, the broken main gear and the landing skids (with Gorilla Gear.) I also took the opportunity to repair some previously slightly damaged tail boom parts and replaced the plastic tail rotor bellcrank with an aftermarket aluminum one. I then replaced the JR 6102/R700 FM radio system with a new Spektrum DX7/R6100. I do not expect glitches with that one. As I stated before, I had the heli guys at the local Hobby Shop (Remote Control Hobbies, Woodinville, WA) go thru the setup with me and show me what I need to do to keep this bird flying. So far the problem has not repeated, and I have been able to resume my practicing, albeit with much more precise control.
Many thanks to the guys at the shop and on this forum.