[twobladeprop]

Hey, I just pick up a t-rex 600 it has jr8717 servos and a jr7703d gyro backed up with a jr 8900 . Carbon everywhere(boom,frame,blades,paddles).
It has a 100 amp esc spinning a Align 650 engine(black w/silver cooling fins), being fed by a 6S 30C 5000mah. It has also the helical/bevel gearing in it. Pinion is a 16t and the main gear is a 188t. On the ground under zero head speed the cylclic is smooth as ice, also centers everytime, and also crazy fast. In a hover I will trim it to hang there on its own. After a little forward flight I will return to a hover and its trim will be completely out of wack.. And also under some extreme moves I can't get the blades to make that poping sound that so many others do. I wonder if it is my power set up. Any help would be great I am completely new to helis and plunged head first into a 600. Hopefully it was the right decision.

[chris p]

if the head dampers are worn out that can effect the trim, or maybe there is a servo with a broken gear or arm that is moveing.
as for the blade pop,what head speed and pitch are you running, the popping of the blades will occure when there is alot of deflection

[Perry3182]

Is this all new or used gear? I'd suspect the battery if you have no history of it. Battery could be old and tired. If you have more than one and it's doing the same thing on all of them then that would rule that out.

[MarkToo]

Take one blade off and put a hex wrench on the grip bolt and spin it. Watch the other blade to see if it's tip is moving around at all when you do this. A bent spindle will throw the blades out of whack.

Also, since you're new to helis, you flight trim will only be valid if you're hovering with the wind in the same orientation as you trimmed the heli.

If you move the heli around so a different side is facing the wind, it will need to be trimmed again for a "hands off" hover.

Be advised, there is no such thing as a hands off hover (without electronic assistance). It may be very stable but, you'll always be flying it.

As far as the cool blade noise goes...

Since you're new, you'll likely hear that mostly when you're over correcting while trying to save the heli from disaster at this point. Trying to make that noise without really knowing what you're doing will likely put undue strain on your machine. Get comfortable flying around - and keep listening. You'll hear it...

Mark

[twobladeprop]

Originally Posted by Perry3182

Is this all new or used gear? I'd suspect the battery if you have no history of it. Battery could be old and tired. If you have more than one and it's doing the same thing on all of them then that would rule that out.

All new batteries, new motor and esc. It origanally had a 4500 mah 6s pack and the old 600 motor on a 65 amp esc.

[twobladeprop]

Originally Posted by chris p

if the head dampers are worn out that can effect the trim, or maybe there is a servo with a broken gear or arm that is moveing.
as for the blade pop,what head speed and pitch are you running, the popping of the blades will occure when there is alot of deflection

Not to sure of actual head speed, But with a online head speed calculaor with my setup it should be around 2100 rpm. And running -10/+10 pitch

[twobladeprop]

Originally Posted by MarkToo

Take one blade off and put a hex wrench on the grip bolt and spin it. Watch the other blade to see if it's tip is moving around at all when you do this. A bent spindle will throw the blades out of whack.

Also, since you're new to helis, you flight trim will only be valid if you're hovering with the wind in the same orientation as you trimmed the heli.

If you move the heli around so a different side is facing the wind, it will need to be trimmed again for a "hands off" hover.

Be advised, there is no such thing as a hands off hover (without electronic assistance). It may be very stable but, you'll always be flying it.

As far as the cool blade noise goes...

Since you're new, you'll likely hear that mostly when you're over correcting while trying to save the heli from disaster at this point. Trying to make that noise without really knowing what you're doing will likely put undue strain on your machine. Get comfortable flying around - and keep listening. You'll hear it...

Mark

I will try that spindle check , Also no wind to speak of that day.
I figured out that I am always needing to fly that heli but the centring just doesn't seem to be the same. I guess it's just something I have to get used to. Lol NO saving my heli from disaster here. I tend to keep plenty of alltitude for at least 1 mistake high. I would hold the tail vertical and cylcle in a big circle like ive seen done before and there helis just made a lot more noise.

[NTM]

+-10 degrees isn't much pitch, more pitch gets you more noise.
Blades also play a part, radix are quiet compared to v-blades.

I'd also check the thrust bearings and make sure you have a neutral cg.
Also make sure one of your paddles isn't shifting around on the flybar.

[twobladeprop]

Originally Posted by NTM

+-10 degrees isn't much pitch, more pitch gets you more noise.
Blades also play a part, radix are quiet compared to v-blades.

I'd also check the thrust bearings and make sure you have a neutral cg.
Also make sure one of your paddles isn't shifting around on the flybar.

That is all the pitch that i can get... i can get 14 but then my swash plate binds big time when i combine pictch with any other axis. I'm runnig carbon blades from NHP (northern helicopter products) Thrust bearings check out OK.. And I am a stickler for tight nuts and bolts lol.. Meaning my entire head is tight. And vibe free. Maybe i am running to much aileron and elevator. I think an at 38% in my dx7 setting for the swash travel for those two.

[twobladeprop]

Originally Posted by chris p

if the head dampers are worn out that can effect the trim, or maybe there is a servo with a broken gear or arm that is moveing.
as for the blade pop,what head speed and pitch are you running, the popping of the blades will occure when there is alot of deflection

Turns out i'm also running a ground head speed of 2145 rpm. Checked it yesterday afternoon.