600 Trex 550 dfc rotor head vibration
- Thread starter PHIL1234
- Start date
Hi Phil1234!
First off, post an introduction of yourself in the new member intro section: New Member Introduction
As for your issue could be a number of issues:
- Blades out of balance: rare on blades these days, but has been known to happen.
- Bend main shaft: rare on a new part from manufacturer, but also known to happen.
- Blades severely out of tracking: when you setup the helicopter did you make sure both blades were at 0 pitch at mid stick? If one of the blades is significantly out of adjustment it can result in a heavy flutter an vibration.
- Normal vibration: During spool up there will be points in the head spin up that the heli shuffles or vibrates a bit. You're just hitting resonant frequencies and it will settle out at you bring it up to speed.
- Head speed too low: If you have a wobble when trying to take off it may be because you have your throttle curve too low, resulting in slow headspeed at lift off/hover which can lead to a wobble in the heli.
Without more info it is hard to say what it is. Can you take a video and post it for us? Is this a new build or are you rebuilding from a crash?
You can help eliminate some possibilities by doing a spin up test wit the blades off the helicopter. See if you can see that the main shaft is bent or if anything is wobbling in a bad way. With the blades off you can actually touch the heli and see if you feel any obnoxious vibrations.
First off, post an introduction of yourself in the new member intro section: New Member Introduction
As for your issue could be a number of issues:
- Blades out of balance: rare on blades these days, but has been known to happen.
- Bend main shaft: rare on a new part from manufacturer, but also known to happen.
- Blades severely out of tracking: when you setup the helicopter did you make sure both blades were at 0 pitch at mid stick? If one of the blades is significantly out of adjustment it can result in a heavy flutter an vibration.
- Normal vibration: During spool up there will be points in the head spin up that the heli shuffles or vibrates a bit. You're just hitting resonant frequencies and it will settle out at you bring it up to speed.
- Head speed too low: If you have a wobble when trying to take off it may be because you have your throttle curve too low, resulting in slow headspeed at lift off/hover which can lead to a wobble in the heli.
Without more info it is hard to say what it is. Can you take a video and post it for us? Is this a new build or are you rebuilding from a crash?
You can help eliminate some possibilities by doing a spin up test wit the blades off the helicopter. See if you can see that the main shaft is bent or if anything is wobbling in a bad way. With the blades off you can actually touch the heli and see if you feel any obnoxious vibrations.
Tony
Staff member
Another thing that it could be is the blades way too tight, or way too loose, depending on when the vibration is. If it's during spool up, then they are too loose and need to be tightened. If it's when you are in the air, they could be too tight. Also, make sure both blades are the same tightness. You do this by holding the blades horizontal, slightly jerking the heli, and the blades should drop the same amount (about 45º).
PHIL1234
Member
I have checked to see if it 0 degrees pitch at mid stick which it is and high stick +12 low stick -12 and the elevator and aileron + and - 10
I also checked the blades which were too tight and have sorted that out, can you tell me where do i post the video after I done it tomorrow
many thanks Phil.
I have a Dx7s with this heli can you help me about the gyro gain starting points my settings are -30 rate mode, 31 and 32 HH mode, thanks.
I also checked the blades which were too tight and have sorted that out, can you tell me where do i post the video after I done it tomorrow
many thanks Phil.
I have a Dx7s with this heli can you help me about the gyro gain starting points my settings are -30 rate mode, 31 and 32 HH mode, thanks.
coolgabsi
Super Mod & DEAL KING!
Vibration without main blades on the main shaft????
Check bearings abd bearing block alignment.. When you built this bird, did you make sure the two or three bearing blocks were perfectly aligned to where the main shaft would slide effortlessly through the three bearings back and forth?
May be check that also..
If you have checked feather in shaft already... Then is your gear mesh too tight?
Is the main gear warped too far.. I know the main gears come warped out of their molds.. But too much doesn't help .. So check that
Check bearings abd bearing block alignment.. When you built this bird, did you make sure the two or three bearing blocks were perfectly aligned to where the main shaft would slide effortlessly through the three bearings back and forth?
May be check that also..
If you have checked feather in shaft already... Then is your gear mesh too tight?
Is the main gear warped too far.. I know the main gears come warped out of their molds.. But too much doesn't help .. So check that
Slobberdog
Well-Known Member
Heli looks good, but hovering in a small space with a clothes line above the Heli I personally would not do, all it takes is a bit of transitional lift and you will end up with a tangle,
Good control though
Good control though
Slobberdog
Well-Known Member
I done it with my 130x and it scared the hell out of me, but I don't think a large heli would survive like my small one.
I think most on here would agree, don't do it even like you said if its just to get the video, if you don't feel safe
I think most on here would agree, don't do it even like you said if its just to get the video, if you don't feel safe
Graham Lawrie
Well-Known Member
Could not see any vibration in the video? Were you fighting the tail going right? Good hovering
PHIL1234
Member
all the suggesttion and problems that were suggested to me by other members, i checked, i rebuilt head and tail so i could check the main shaft the feathering shaft and the tail shaft, everything was ok, i checked the main bearing block and the main gear
and everything was fine, i did have the main blades to tight and i loosened them off, i am not fighting with the tail at all its flying champion, i would like to thank everybody for their help.
and everything was fine, i did have the main blades to tight and i loosened them off, i am not fighting with the tail at all its flying champion, i would like to thank everybody for their help.
pj1969
Member
Looked fine to me, only thing shaking was your mates hand lol, made me sea sick haha, I'd check head speed too, I had a small shake on my 450 and as soon as I used IU1 it cleared. Plus one with Kev tho, washing line and spinning blades don't mix, take it from one that knows. Happy flying
EyeStation
Well-Known Member
Did Youtubes anti-shake transfer the shakes to the rest of the video and leave the heli looking stable? I thought the heli looked solid through the video shakes.