Vibration re sent
- Thread starter treff
- Start date
Slobberdog
Well-Known Member
Lee I think he means its very loose on the shaft and hence wobbling.
This afternoon, evening I have changed the main shaft. I have fitted another feathering shaft just in case. I have redone the tracking on new blades. I have checked the pitch and all looks good zero at midstick and 11 degrees up and down on both blades. Still the vibration persists, Very strangely and I do not know wether this as any effect but the gyro is changing direction, reversing. I think this maybe the vibrations effecting the electronics somehow. I don't really know. It would be nice to have a vibration free bird but I do not mind really. I am getting plenty of hovering practice and my next training step is to get more precision, getting the heli to go where I want to put it. Next week I will send for a new tail section but with so many variants of this model I'm not sure which one to get. The helicopter is the HK gt450 pro2 so any suggestions will be most welcome. Cheers
PS I also checked the head, running the motor up without the blades and it is rock solid now, now wobbles or movement.
PS I also checked the head, running the motor up without the blades and it is rock solid now, now wobbles or movement.
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Graham Lawrie
Well-Known Member
Excellent flying skills Treff considering the vibrations you have
Well Done If everything is ok with the blades off it does not necessarily mean it is a blade fault when they are on. The blades when on will then exaggerate any play you have. I am interested in the amount of movement up and down you describe. When i built my 450, like Tonys build video at first i did not fit shims on the main shaft. I then split it to re-route the wires and had play so i fitted the shims. Did yours come with shims to take out the play between the main shaft and the main bearings?
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I have just watched your video again and i see what you mean the whole bird is shaking.Very visible before you lift off on the landing gear. It also looks as if the main blades are tilting to the right(aeleron side), which may suggest movement in your head dampers, or swash not level, which could also be a servo or tx setting error.
Well Done If everything is ok with the blades off it does not necessarily mean it is a blade fault when they are on. The blades when on will then exaggerate any play you have. I am interested in the amount of movement up and down you describe. When i built my 450, like Tonys build video at first i did not fit shims on the main shaft. I then split it to re-route the wires and had play so i fitted the shims. Did yours come with shims to take out the play between the main shaft and the main bearings?- - - Updated - - -
I have just watched your video again and i see what you mean the whole bird is shaking.Very visible before you lift off on the landing gear. It also looks as if the main blades are tilting to the right(aeleron side), which may suggest movement in your head dampers, or swash not level, which could also be a servo or tx setting error.
Hi Graham thanks for the info and reply. No there were no shims and I can not feel any play in the shaft. I have a feeling that the vibration is from the tail. Its the only place that as hit the ground if you know what I mean. I broke a Tail blade off and really apart from a couple of tip overs on landing and at very low rpm in the rotor the heli is new. I will send for a new tail section. The problem I have is which one? . I think the belt drives are all different lengths. I did not want to buy another HK one so I will probably go to Giantshark and try one of those. Align is very expensive and then you have to buy the belt, slider, crank all seperately, almost the cost of a new heli from HK. I was also thinking of converting to TT but am not sure if that is possible on this model. Don't get me wrong still having loads of fun but need more batteries LOL. Cheers
DAL2855
Banned
Treff, check on ebay! You can find the tailboxes rather inexpensive on there!
Align Trex 450 Sport Metal Tail Belt Unit H45101A | eBay
This one will fit your bird!
Align Trex 450 Sport Metal Tail Belt Unit H45101A | eBay
This one will fit your bird!
idon'tknow!
rc-help EXPERT.......????
I had some vibes on my 500, awhile back and like you just could not locate the cause. I was told to take everything off both rotors than add things to it, in that way i found out that my head black (which had been through a crash or two) was bent, and even cracked in one place. it would spin up fine and look solid, but that was because now it fit very loosely on the shaft, because of the gyroscope effect on it would look like it was running smooth, the only way Ii could tell it was the head block was when I put it on the shaft vibes started. a few weeks later when i had gotten a align rotor head + new align blades and tail unit it was vibe free. My first blades like yours, they didn't look to good; when i replaced them, and balanced the new ones the heli worked 100% better. So my suggestion to you would be take the heli apart, even as far as taking the boom off, and slowly build up, checking for the slightest vibes, remember that blades, booms, tail blades, fly bar...etc are amplifiers, so as you strip down the vibes will be less, and less noticeable. here is a video of my 500 with a vibe issue. Notice the blade grips?
and now look at this video... this is the heli flying low head speed with a vibe...notice the chipping?
and here it is high head speed, vibe free.
hope this helps some.
and now look at this video... this is the heli flying low head speed with a vibe...notice the chipping?
and here it is high head speed, vibe free.
hope this helps some.
Last edited by a moderator:
rchelipilot
Member
I remember when you went through that IDK. It sometimes takes perseverance to find the source.....or sources.
