EXI 500 Head Wobble and Serious Vibration
02-19-2010, 12:43 PM
#1
Thread Starter
My Feedback: (13)
Join Date: Jun 2002
Location: Williamstown,
NJ
Posts: 905
Likes: 0
Received 0 Likes
on
0 Posts
EXI 500 Head Wobble and Serious Vibration
This heli is really frustrating me. I have now upgraded to Align Trex main shaft, feathering shaft, and tail rotor shaft because ALL were bent in the kit I received and had to just throw them out. Now I have straight shafts it still vibrates like crazy and it is impossible to get the blades tracking. The tail boom brace actually snapped just below the bolt because of the vibration. The new tail rotor shaft eliminated the vibration in the tail however the head still wobbles really bad. The tracking is way off! At the tip it is probabaly 1/2". If you turn the upper link just 1 turn, the high blade becomes the low blade byt the same amount of a 1/2". If you adjust the lower link, which should be equivalent to a half turn on the upper link, it does the same thing. I replaced the stock dampers in the blade grips with harder upgraded dampers and they don't help either.
This heli is obviously flawed and is not possible to set up. I have been patient with it, but how now invested far too much time and money on upgrades than I should have to on a brand new helicopter.
Please get back to.
Thank you,
Brian
This heli is obviously flawed and is not possible to set up. I have been patient with it, but how now invested far too much time and money on upgrades than I should have to on a brand new helicopter.
Please get back to.
Thank you,
Brian
02-19-2010, 01:30 PM
#2
Join Date: Nov 2005
Location: Poolesville, MD
Posts: 12,624
Likes: 0
Received 0 Likes
on
0 Posts
RE: EXI 500 Head Wobble and Serious Vibration
I've seen several EXI 500 fly just fine and I built my own 450 from the kit that NP sells.
We have several club members with these helis and none have problems, though everyone is pretty experienced with this stuff.
If you've replaced the main shaft, etc. the first test you should perform is to spin up the head with the blades removed to check for balance in all of the head components.
There should be NO wobble what-so-ever at this point, and any that exists must be corrected.
That the shafts arrived bent, indicates a big problem with what you recieved. As if it has been flown and crashed!
PM John here ( Nitrostaff1 ) with your order number, reference this thread.
It sounds like the entire heli needs replacement.
We have several club members with these helis and none have problems, though everyone is pretty experienced with this stuff.
If you've replaced the main shaft, etc. the first test you should perform is to spin up the head with the blades removed to check for balance in all of the head components.
There should be NO wobble what-so-ever at this point, and any that exists must be corrected.
That the shafts arrived bent, indicates a big problem with what you recieved. As if it has been flown and crashed!
PM John here ( Nitrostaff1 ) with your order number, reference this thread.
It sounds like the entire heli needs replacement.
02-19-2010, 01:37 PM
#3
Thread Starter
My Feedback: (13)
Join Date: Jun 2002
Location: Williamstown,
NJ
Posts: 905
Likes: 0
Received 0 Likes
on
0 Posts
RE: EXI 500 Head Wobble and Serious Vibration
Hey,
That was actually a test I had done a while ago. The head has a very visable wobble in it with the blades off as well. I thought at first it was just the head button off center which I have seen before and gives the illusion of the head wobbling. It is the head for sure though. I just took the whole head off and ran it and runs very smooth. I rolled the main shaft on a glass table and it is straight. It is something in the head that is the problem.
I have read the several people have had bent tail shafts with there EXI 500 so that is nothing new. the tail shaft was bend so bad, yes it looked like it was crashed! My main shaft and feathering spindle were just slightly off, nothing major but I replaced them to be safe and have a better flying heli.
I am no expert pilot, but at least this shows I DO know what I am doign when it comes to setting up a heli.
http://www.youtube.com/watch?v=r40dYzoi8Us
Brian
That was actually a test I had done a while ago. The head has a very visable wobble in it with the blades off as well. I thought at first it was just the head button off center which I have seen before and gives the illusion of the head wobbling. It is the head for sure though. I just took the whole head off and ran it and runs very smooth. I rolled the main shaft on a glass table and it is straight. It is something in the head that is the problem.
I have read the several people have had bent tail shafts with there EXI 500 so that is nothing new. the tail shaft was bend so bad, yes it looked like it was crashed! My main shaft and feathering spindle were just slightly off, nothing major but I replaced them to be safe and have a better flying heli.
I am no expert pilot, but at least this shows I DO know what I am doign when it comes to setting up a heli.
http://www.youtube.com/watch?v=r40dYzoi8Us
Brian
ORIGINAL: opjose
I've seen several EXI 500 fly just fine and I built my own 450 from the kit that NP sells.
We have several club members with these helis and none have problems, though everyone is pretty experienced with this stuff.
If you've replaced the main shaft, etc. the first test you should perform is to spin up the head with the blades removed to check for balance in all of the head components.
There should be NO wobble what-so-ever at this point, and any that exists must be corrected.
That the shafts arrived bent, indicates a big problem with what you recieved. As if it has been flown and crashed!
PM John here ( Nitrostaff1 ) with your order number, reference this thread.
It sounds like the entire heli needs replacement.
I've seen several EXI 500 fly just fine and I built my own 450 from the kit that NP sells.
We have several club members with these helis and none have problems, though everyone is pretty experienced with this stuff.
If you've replaced the main shaft, etc. the first test you should perform is to spin up the head with the blades removed to check for balance in all of the head components.
There should be NO wobble what-so-ever at this point, and any that exists must be corrected.
That the shafts arrived bent, indicates a big problem with what you recieved. As if it has been flown and crashed!
PM John here ( Nitrostaff1 ) with your order number, reference this thread.
It sounds like the entire heli needs replacement.
02-19-2010, 03:37 PM
#4
Thread Starter
My Feedback: (13)
Join Date: Jun 2002
Location: Williamstown,
NJ
Posts: 905
Likes: 0
Received 0 Likes
on
0 Posts
RE: EXI 500 Head Wobble and Serious Vibration
Here is what the wobble looks like. Watch the head wobble around as well as the battery vibrate. The skids are almost all the way work down from vibrating all over the driveway while trying to fix it.
http://www.youtube.com/watch?v=u6vxSXPFdU0
Brian
http://www.youtube.com/watch?v=u6vxSXPFdU0
Brian
02-19-2010, 03:43 PM
#5
Join Date: Nov 2005
Location: Poolesville, MD
Posts: 12,624
Likes: 0
Received 0 Likes
on
0 Posts
RE: EXI 500 Head Wobble and Serious Vibration
Nasty!
To best illustrate the problem, it would have been nice to remove the flybar and the blades.
That takes unbalanced flybar paddles and blades out of the demonstration, in your video.
If the heli still wobbles without both, there is something amiss with the shaft, linkages or bearings.
To best illustrate the problem, it would have been nice to remove the flybar and the blades.
That takes unbalanced flybar paddles and blades out of the demonstration, in your video.
If the heli still wobbles without both, there is something amiss with the shaft, linkages or bearings.
02-19-2010, 03:53 PM
#6
Thread Starter
My Feedback: (13)
Join Date: Jun 2002
Location: Williamstown,
NJ
Posts: 905
Likes: 0
Received 0 Likes
on
0 Posts
RE: EXI 500 Head Wobble and Serious Vibration
You mean like this? haha. It was so hard to film it. it looks waaaay worse in person. Watch the top of the head in relation to panels on the door and you will see it though.
I know the flybar is still on it but trust me the flybar is perfectly centered(even had to extend the factory flat spots to move in 1mm) and then the paddles were installed at equal disatances.
the head is messed up, I have no doubt.
http://www.youtube.com/watch?v=O9Rnwv9CSYk
I know the flybar is still on it but trust me the flybar is perfectly centered(even had to extend the factory flat spots to move in 1mm) and then the paddles were installed at equal disatances.
the head is messed up, I have no doubt.
http://www.youtube.com/watch?v=O9Rnwv9CSYk
ORIGINAL: opjose
Nasty!
To best illustrate the problem, it would have been nice to remove the flybar and the blades.
That takes unbalanced flybar paddles and blades out of the demonstration, in your video.
If the heli still wobbles without both, there is something amiss with the shaft, linkages or bearings.
Nasty!
To best illustrate the problem, it would have been nice to remove the flybar and the blades.
That takes unbalanced flybar paddles and blades out of the demonstration, in your video.
If the heli still wobbles without both, there is something amiss with the shaft, linkages or bearings.
02-19-2010, 04:56 PM
#8
Thread Starter
My Feedback: (13)
Join Date: Jun 2002
Location: Williamstown,
NJ
Posts: 905
Likes: 0
Received 0 Likes
on
0 Posts
RE: EXI 500 Head Wobble and Serious Vibration
Here is a video of it running with the head removed and only the Align Trex shaft still installed. As you can see there is no wobble at all. The problem is in the head ...I am 100% sure.
http://www.youtube.com/watch?v=LWkMrBOfoFU
Brian
http://www.youtube.com/watch?v=LWkMrBOfoFU
Brian
