Hey guys. dusted off the 450's and of course crashed out of the gate. kind of went crazy for no reason I could find. But at any rate the reason I'm baffled is that when setting the bird back up I find that at full throttle I have one blade that has +9.5 positive pitch and -9.5 negative pitch closed throttle. The problem is that the other blade only has +8.1 at full throttle and -8.3 at closed throttle.Anyone have a clue what I fouled up this time? Oh and both blades are at 0 pitch at mid stick.
450 uneven blade pitch
- Thread starter hawk-i
- Start date
When using a digital pitch gauge you need to rotate the rotor around and measure from the same spot you took your initial reading. So if you zeroed on the head button or motor or something, and then took an angle reading on one blade off the front of the heli, then you need to rotate the other rotor blade around to you (without moving the heli) at that same spot and take its reading. IF you move to take the opposite blade's reading from the other side, it is very possible the zero of the gauge is not correct over there.
So pretty much your saying what is happening to me don't make a lot of sense. Most likely pilot error. It don't make a lot of sense to me either. You would think one blade wouldn't travel any farther than the other. I'll try my mechanical gauge and see what I get. Thanks a lot for your time . I'll let you know how it went.
The zeroing issue is why I usually use a manual dial gauge instead of the digital.
If you find that there really is a difference in range on one blade compared to the other:
1) Make sure the blades are straight out from the hub. IF they are a bit forward or back it can exaggerate readings.
2) Make sure the ball on the swash is the same length for both sides where the pitch links hook up.
3) Make sure the blade holder arm and ball end are the same distance from hub center when at 0.
On 2 and 3, if one is shorter than the other it will reduce the range of blade angle.
If you find that there really is a difference in range on one blade compared to the other:
1) Make sure the blades are straight out from the hub. IF they are a bit forward or back it can exaggerate readings.
2) Make sure the ball on the swash is the same length for both sides where the pitch links hook up.
3) Make sure the blade holder arm and ball end are the same distance from hub center when at 0.
On 2 and 3, if one is shorter than the other it will reduce the range of blade angle.
Thanks I'll check all those things. I think I'm going to strip the head all the way down and check all the linkages for wear and set everything up to factory spec again. One question. How critical is it that the washout arms be level? Seems that when measure linkages and put them to spec the arms are never level. I know I have some heads that have solid top linkages and are not adjustable.
murankar
Staff member
After reviewing your past posts I might have an answer.
All if this will be done in iu1 with throttle hold on or motor disconnected and throttle at mid stick.
With flybared helis you start the setup with the servo arms.
First make sure the servo arms are at 90° to the swash linkages
then ensure the linkages themselves are at proper length per manufacturer
Check for a level swash
Move up to the washout hub and check to see if the arms make a 90° angle at the hub joint
Next is the flybar cage. With the flybar locked it should be level and the paddles should be level to the cage, basically 0° pitch.
Finally check the pitch of the main blades, they should be at zero degrees. If not adjust the closest links to the blade grips until it is as zero as you can get.
Make sure all links start out at factory lengths and that the link ends are a square to the ball link as possible. This should cover the first half of the setup. Do not move on until that is a perfect as possible.
Sent from my LG-E980 using Forum Runner
All if this will be done in iu1 with throttle hold on or motor disconnected and throttle at mid stick.
With flybared helis you start the setup with the servo arms.
First make sure the servo arms are at 90° to the swash linkages
then ensure the linkages themselves are at proper length per manufacturer
Check for a level swash
Move up to the washout hub and check to see if the arms make a 90° angle at the hub joint
Next is the flybar cage. With the flybar locked it should be level and the paddles should be level to the cage, basically 0° pitch.
Finally check the pitch of the main blades, they should be at zero degrees. If not adjust the closest links to the blade grips until it is as zero as you can get.
Make sure all links start out at factory lengths and that the link ends are a square to the ball link as possible. This should cover the first half of the setup. Do not move on until that is a perfect as possible.
Sent from my LG-E980 using Forum Runner
murankar
Staff member
Forgot something.
If the swash is not level then level it. This may take a combination of sub trim and linkage adjustments.
Also once the fly bar is locked make sure the cage is level. If not adjust linkages accordingly.
Some kits come with solid links. If this is the case then you will need to get it as best you can. Tony has a 1 hour build video of the EXI torque tube kit that has solid links. That video will help you. I think the head set up is near the 45 minute mark.
Sent from my LG-E980 using Forum Runner
If the swash is not level then level it. This may take a combination of sub trim and linkage adjustments.
Also once the fly bar is locked make sure the cage is level. If not adjust linkages accordingly.
Some kits come with solid links. If this is the case then you will need to get it as best you can. Tony has a 1 hour build video of the EXI torque tube kit that has solid links. That video will help you. I think the head set up is near the 45 minute mark.
Sent from my LG-E980 using Forum Runner
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