Blade CX2 needs constant trim adjustment

[bigdumbdane]

My blade CX2 doesnt seem to be consistant on the trim over each run.

When I gfirst start up, the rotation trim (the left/right on the left - sorry, not sure if that is the right term) needs to be all the way to the left. I have adjusted everything so that it will stick perfect when I first start a flight like this.
As I fly around, I need to keep adjusting the trim towards the left...
By 1/2 way though the battery, it is all the way to the left, and I need to move the paddle to the left as well..

By the end of the flight, left turns make it drop, and are very slow. The right turns are quite fast, and do not affect the altitude.

It seems like the lower blades are loosing power, but the upper blades are fine.

I dont think it is the motors, it has always been this way - in fact, it seems better now that I have flown it more and "dialed it in".
Doesnt seem to be the battery, I have 2 and they both do the same.

I read that the original CX had problems with this due to heat affecting the gyro or something, but was under the impression that was fixed in the new cx2.

Any ideas? I would like to get it fixed, as it makes the last 1/4 of my flight very weak.

[livesounder]

Your description seems contradictory. Please clarify what's happening, and make sure that when you describe the movement of the heli, you're talking about which way the nose (Not the tail) moves.

BTW - the "left/right on the left" is the rudder.

[bigdumbdane]

Your description seems contradictory. Please clarify what's happening, and make sure that when you describe the movement of the heli, you're talking about which way the nose (Not the tail) moves.

BTW - the "left/right on the left" is the rudder.

Sorry - the nose starts by spinning to the left, and ends up spinning to the right.

hence I have to start with the rudder trim to the right and then eventually move it all the way to the left, with additional input to the left from the rudder itself to keep the nose straight.

[Jermo]

That's by design. The heli doesn't have a heading hold gyro installed. As the temperature near the gyro changes (from the speed controller chip to the motor), it causes the gyro to change which you see as tail movement. You can adjust it to minimize the effect but ultimately you end up either constantly adjusting trim or just learning to fly the tail.
Jermo

[Taffey]

Yep, that's classic CX. Heat is indeed the culprit.

Cutting some cooling holes in your canopy will help a little. For real results, though, remove the plastic case from your 4-in-1 and stick the circuit board directly to your frame with 2-sided tape. Your tail wandering issues will be drastically reduced, and you'll save a little weight as well.

[bigdumbdane]

Yep, that's classic CX. Heat is indeed the culprit.

Cutting some cooling holes in your canopy will help a little. For real results, though, remove the plastic case from your 4-in-1 and stick the circuit board directly to your frame with 2-sided tape. Your tail wandering issues will be drastically reduced, and you'll save a little weight as well.

Thanks.. I guess it's not too bad, and it is teaching me to fly with constant adjustment.
Does the blade CP Pro do this as well? I was thinking of getting a esky cp2 with a heading lock gyro on it, or a trex 450 if I can wait another month to save up... do those types of "heading lock" gyros get affected by heat as well?

[Jermo]

Your call but I'd wait a month and get a T-Rex. All gyro's are affected by head/vibration. This is clearly a poor design. If you add a heatsink to the motor controller chip or cut holes in the canopy/rx case the issues diminish dramatically to the point of being flyable.
Jermo

[Rick Rotorhead]

Funny, my CX2 is actually pretty good on the tail. I mean it still drifts and I've never been able to get it to sit there hands off, but its a gradual turn and you just learn to hold the required amount of left stick to keep her in neutral hover, then add a little rudder or take some off as necessary to effect turns. The technical 'neutral position' on the Tx doesn't really matter.

What IS good, is the way the tail is fairly well behaved when adding or taking throttle, again slight adjustment is needed as you throttle up or down, but not huge amounts.

Compared to my boys 'EasyCopter V2' (another CoAx) ,the CX2 is sedate and stable - a pleasure to cruise around.

[bigdumbdane]

Well I just added a "custom air intake snorkel" to the front of the CX2 -

(Actually, I crashed it into the house and broke a nice hole in the nose)

This seems to help a little with the cooling. Maybe I will drill holes in the case next to see if that helps any more.

[Raysun]

All of my non-heading hold helis will drift to some degree, including cx, cx-2, cpppro. Trick is to adjust proportional trim pot on 4;1 so drift is minimal on a Full battery, then you do need to fly the tail a bit as pack burns down. I cut a small access opening in my canopy where the two pots are to allow adjustment without pulling the canopy off.

Make sure heli is trimmed perfectly for fore/aft and left/right cyclic before you worry about tail...do this by lenghtening/shortening servo linkages to swashplate. Trim tail last.

Ray

[Jeff0r3]

I cut a small access opening in my canopy where the two pots are to allow adjustment without pulling the canopy off.

Brilliant! Why didn't I think of that....Thanks for that idea, I've been buggin with this canopy all night..

Jeff