farmerjoe

I'm having problems with the rear rotor trim on my Belt CP. Ihave to have the trim ALLthe way over to the right, and it still takes a small amount of right stick to keep the heli centered. I've adjusted the servo to get max throw on the rear rotor assembly in that direction, and I've also cut down on the pitch a bit to make sure the rear rotor is spinning fast enough for a given amount of lift. I haven't always had this problem, so I'm not sure what has changed. Blade pitch is right at zero on fully down throttle stick, and the hover/pitch knob on the Esky radio is only one quarter of the way up, in it's adjustment. I've checked belt tension, and it is fine. Has anyone else had this problem, or does anyone else have any suggestions?

Angel_W

Hi, farmerjoe:
have you checked the tail servo is secure and not sliding on the tail boom? You can also trim the rotor by moving servo nearer the tail rotor till you get your trims close to the central point (or away).

farmerjoe

Yes, I've slid the servo all the way back, just prior to the point that it would bind the rear rotor assembly. I have aluminum clamps on the servo and it is secure. Even with doing this, I still have to move the trim on the radio all the way to the right. I didn't have to do this before. Something has changed and I cannot figure it out.

Angel_W

Let's try another thing: you better get rpms on  tail rotor so,  move the hover trim about one point to the right and the pitch trim to the middle position. This setting should give you thrust enough which could be the solution.

Tinkman

The other possibility is that the tail rotor drive pulley is slipping somehow, causing slow rotation.
One other possibility: Did you take the tail assy apart lately? If the tail rotor is spinning backwards it may not run as efficiently as it's supposed to. When viewing the bird from the right side, the tail rotor should be turning counter clockwise.

Joaquin

Navy_1

try adjusting you tail boom out just a little to tighten up your belt. also look at what hole you linkage is in on teh servo. there is a thred just above this on that says Belt-CP all us belt guys are in there just jump in adn ask there is lots to lerne in there

farmerjoe

Ok. I've covered all the bases suggested here, earlier, with the exception of changing the "pitch trim" and "hover trim". I'm aware of the hover trim knob on the Esky radio, but I don't understand the pitch trim (I assume you are talking about the trim on the throttle), and what it would do for the heli. I thought it just moved the whole throttle curve (combination of throttle and pitch) up, when Imoved it up.

I did the suggestion that Angel asked for. Moved the pitch trim up to the middle (I call it throttle trim), and moved the hover pitch slightly right. It DIDin fact help the situation, as the tail would hold centered, without any stick input (with the tail trim fully right, still). The only problem I had, after doing this, was that when I did a fast increase in throttle, the bird would rotate about 270 degrees, before the gyro "caught" it. I increased the gyro knob on the radio to max, and that seemed to help a bit, but not fully.

Can someone explain to me, what increasing the pitch trim (trim on the throttle on the radio) did to help this problem. I want to be able to understand what is happening here. This helped hold the tail under static throttle conditions, but made a problem when I'm increasing throttle. Thanks for all the suggestions, so far, as Ifeel like Iam making progress!

Angel_W

Glad to hear things go better to you.
Probably your bird has the "professional Gyro" with no head locking and your Tx has no serttings to compensate cyclic or pitch. Whenever you increase rotor speed some control is needed on tail to correct torque effect. This is something you have to deal with. The solution could be changing your regular gyro for a head lock one and a better radio set. Nevertheless, by now, try increasing gyro sensitivity as well as taking a look at the position of the tail rotor blade fixed shaft and try to move it as far as it can go to increase blades angle. Now you should get a quicker response on any heading variation (sesitivity), and a trim possition closer to the center point (more thrust). By the way, have you try Idle-Up yet? Your machine will behave differently and I don't know why but it seems in this position there is some kind of non programable compensation when pitch or ciclic is used, but this is just a gessing.
Sorry I'm unable to upload any pict or video to illustrate. Don't know how.
Good luck

farmerjoe

Well, I do have the Esky 2.4 radio, which I'm sure, isn't the best. It does have a heading hold feature for the gyro, and the sensitivity is adjustable. I don't know what more Ican do with the tail rotor, as I am *****g out the throw (pitch)in the direction needed to fix this problem. What is funny is that it didn't take this much pitch on the rear rotor in the past to counteract the torque of the main rotor. This is what confuses me.

jmann71

are you still using the stock esky blades?? i was having a similar problem and switched to the Align CG corrected blades. they are a little bigger and do improve the tail rotor response.

jason

have pics on profile

Navy_1

the Esky gyro sucks. ok so pitch trim lets you adjust the pitch curve so to speak postive and neg if i rember its a lineauer. its moves the whole thing up or down adn the hover trim adjusts were teh heli hovers at in retrospect to teh throttol stick postion so you can adjust it to hover at about half stick. i use teh DX-7 so every thing on my is digital. remember that the higher teh head speen the more stabel it is. and dont dile out all teh pitch when setting you blade tracking. take a look at teh main Belt-CP thred lots a good info adn more peopole to help its at teh top of this page