A few 450 question ...

[smithysamrc]

I have just finished building my Trex 450 .

When i start to spool up the heli it starts wobbling alot, and rocking, everything is balanced correctly far as i know. ?

When i gain RPM in normal mode the tail seems to wag alot from side to side, not dramatically, but it just wags.

Thanks for all answers

[Mart61]

...everything is balanced correctly far as i know.

How much of it did you actually balance? Did you check the main blades? How tight have you got the main and tail rotor blade grip bolts? Can the blades move reasonably freely?

What gyro are you running and what are it's gain settings?

[andylinney]

The wobble could be just the blades finding their centre in the grips (check they're not too tight. This could cause the vibes. Failing that there's something not right somewhere.

The tail could be the gain being way too high on the gyro. Turn it right down and see if that cures it.

If it doesn't settle once the rpm is up then go back to the building board and triple check everything. Good luck.

[smithysamrc]

How much of it did you actually balance? Did you check the main blades? How tight have you got the main and tail rotor blade grip bolts? Can the blades move reasonably freely?

What gyro are you running and what are it's gain settings?

Ok im not 100% sure what the tightness of the blades have to be. but the tail blades dont dangle down when horizontal, they stay straight.

The rotorblades dont droop down either when i tip the heli to the side.

The gyro is a CopterX GY240 gyro :

Delay: 0-100 = 50
Limit: 60-140 = 100

Thanks

[andylinney]

Loosen the blades a little and try again

[Mart61]

Ok and thanks for the answers. Didn't mean to sound sharp in my reply - just wanted a little more data.

The main blades should be just tight enough to support the blades under their own weight. Pick up the heli, straighten the blades out such that they are horizontal to the ground. They should stay horizontal but, if you give the heli a slight shake up and down, only a slight one, they should droop towards the floor.

Not familiar with your gyro but I would question why the 50 delay. Do you have a fast digital tail servo?

The limit will only affect the travel of the tail pitch slider along the shaft. If it travels from one end of the shaft to the other without causing the servo to bind, then your setting is fine.

Can you see what gain you are using tho?

[smithysamrc]

Ok and thanks for the answers. Didn't mean to sound sharp in my reply - just wanted a little more data.

The main blades should be just tight enough to support the blades under their own weight. Pick up the heli, straighten the blades out such that they are horizontal to the ground. They should stay horizontal but, if you give the heli a slight shake up and down, only a slight one, they should droop towards the floor.

Not familiar with your gyro but I would question why the 50 delay. Do you have a fast digital tail servo?

The limit will only affect the travel of the tail pitch slider along the shaft. If it travels from one end of the shaft to the other without causing the servo to bind, then your setting is fine.

Can you see what gain you are using tho?

Im using a HXT900 servo, there isnt no gain dial on the gyro, im using a dx6i but i am planning on not setting up the gyro using the tx.

Thanks

[Mart61]

im using a dx6i but i am planning on not setting up the gyro using the tx.

Now I'm confused. I don't think you can set up your gyro without using the Tx to control the gain (or sensitivity).

Check the manual here and see what I mean. How do you plan to go thru the "setup" phase shown at the bottom of page one and onto page two without using your Tx?

I think that, if you are not familiar with setting up a gyro, you should pop to a local club and have someone help you with it.

[st200ol]

I don't think the HXT900 is a very good tail servo, you may need to spend a little bit more here to get a top quality response.

I assume its a clone 450? I didn't think anybody would use a HXT900 on an Align 450.