CX2 Trimming For Novice

[consultant]

Got a CX2. Crashed it, not bad. Just cracked body, broken blad tips, and one broken skid. Decided to upgrade the parts. Aluminum lower head, collapsable blades, aluminum swashplate (came with the aluminum upper head). The collapsable blades are a godsend. Now I just need some aluminum landing skids so I stop breaking them!

I can't get it to hover for the life of me. Worked great out of the box of course. Could easily hover it. Is there any step by step 'dummy' instructions.

I'm guessing first thing is to set the remote control trim adjustments to their centers. Then just adjust the helicopter to get it as close as possible to hove, then adjust the remote trim for final adjustments?

What do you adjust first. When I give it some lift (not enough to take off), the tail rotates. That would be the main proportional mix trimmer pot right? Should I adjust that first so the copter doesn't rotate?

Then there's the elevator and aileron trim. I just can't seem to get the aileron trim centered. When the copter starts to lift it always starts to bank to left or right (and forward or back). I've lengthend (unscrewed) the servo pushrod for the aileron trim to try to correct but I just can't seem to get the aileron and elevator control of the copter trimmed our no matter what.

I'm brand new to this and probably don't know what the heck I'm doing. I'm about to give up and take it to the local shop so they can laugh at me.

[heyjack8]

:thumbup: hey bud been there...first thing i'd do is turn both pot adjustments all the way to the right and back off 1/2 turn. you really are trying to get them centered then get your trim tabs all in the center..adjust your linkage so that your swash looks some what level... get a fresh battery and a pot adjustment screw driver and and take it up a bit and see what happens....if it goes forward adjust your linkage again until you get some degree of control ( your trying to get it into a stable hover as best you can at this point with just adjusting your linkage ) with your trim tabs in the center position.........both forwards backwards and side ways......now go to your pot adjustments and make very small turns and recheck..... dont for get to unplug your battery so it will re-arm each time you make your pot adjustments read your manual before you start adjusting the pot..!!! for yaw and blade mixing between upper and lower heads
i even turn off my radio but i'm not sure thats needs to be done this can be a very tedious job to perform you may even go through several batteries...i know i did.....dont give up..it may take awhile but it can be done your cx should hover with very small stick adjustments or trim movements....after you get it the best you think you can then use trim tabs for final adjustment when your in a hover...it will probably never hover for an extended period of time with out some small inputs..to many variables....voltage,battery cond, blade vortex,ect,ect. good luck keep me posted...anyway this is what i went through...pretty much

[MaXThReAT]

I trim my CX2 by turning the gyro gain nearly off. Spool it up and adj the trim as needed. After you get it as centered as possible turn up the gyro. Mine is rock solid using this method. Plus everything else above if it was a bad crash. Level swash. I used a piece of stiff cardboard with a hole in it to better see the level.

[captainjack]

Also remember that when you power up and the heli is getting light you are still in ground effect and they heli will respond a bit different than when its up a foot. When you pop it up about one foot off the ground she will be a bit more stable and your trim setting will be more accurate. I pop mine up about chest level and then try to trim it in the air or land it and make a small trim adjustment and pop it back up until I get her to fly almost hands free. The rudder (yaw) will always be out of trim as the battery dies down or the motors warm up. Just trim the rudder as you fly thru your pack.

[consultant]

Okay I followed all your advice. I got pretty close. Here's the problem though. I've got it to where the helicopter lifts off slowly, nice and level, no turning, dipping, whatever. But after a few seconds it begins to swirl around in a circle sort of like if you tied a string to the top of the shaft and dangled the copter by the string a few feet down and started to gradually twirl the string in a circular motion. I've spent a couple hours adjusting everything and can't get it to not start swirling. Tried with the gain at about 10% and at about 70% and it still does it.

This is SO frustrating.

[consultant]

Another thing I noticed is that when I pitch it forward, it wants to roll to the right even though I'm pressing the control straight forward. But it doesn't roll right (or left) at all when it is lifting off.

I'm screwed. What a waste of money.

[heyjack8]

thats a tuffy....sounds like maybe blades are not tight enough in the grips or your left right trim is still out of whack....also make sure your fly bar is loose and not binding.another thing is your battery moving around could be throwing it off balance..if it hovers with out going right or left seems to me it should go straight when you push the stick straight ahead.......one more thing if you dont maually straighten your blades in the grips before take off you heli will not fly well at all....maybe you'll get some more input on what could be causing that...some times its better to walk away for an hour or so and try again i got very frustrated at times dialing mine in...sounds like maybe pot adjustments not right yet....also i noticed a big difference when i upgraded from stock e-flite batteries.... if your in it for the long haul get your wallet out.....seems like its always something....

[MaXThReAT]

But after a few seconds it begins to swirl around in a circle sort of like if you tied a string to the top of the shaft and dangled the copter by the string a few feet down and started to gradually twirl the string in a circular motion.

I know what you’re talking about. I found that it was either my flybar was bent just a little or the inershaft wasn't snug enough and there was a bit of play. If you check the tracking of the top blades do they oscillate in and out of track?

[carlo_the_wonder_frog]

Okay I followed all your advice. I got pretty close. Here's the problem though. I've got it to where the helicopter lifts off slowly, nice and level, no turning, dipping, whatever. But after a few seconds it begins to swirl around in a circle sort of like if you tied a string to the top of the shaft and dangled the copter by the string a few feet down and started to gradually twirl the string in a circular motion. I've spent a couple hours adjusting everything and can't get it to not start swirling. Tried with the gain at about 10% and at about 70% and it still does it.

This is SO frustrating.


Put the stock blades back on, if it hovers fine then you know its the new microheli blade holders that are causing the problem.

[balbs]

"swirling around in a circle"...sounds like the toilet bowl effect. Make sure the flybar is level with the top blades by adjusting the flybar link.

Balbs

[Dumb Thumbs]

Just what "Frog" said. I've read on another Heli forum that the Microheli grips will make the bird behave like that.