mCP X 1/4 Turns problem

[CrazyComi]

I have been enjoying my mCP X and have about over 50+ flights on it. This weekend I had a crash while backwards flying and after repair of the cracked tail boom I started noticing that my mCP X does involuntary 1/4 turns to the left now. After going through the forum and looking at possible solution nothing worked. I disconnected everything to the 3&1 board and the only thing that I left connected was my tail and it still has the issue. So is this mean I damaged my 3&1? Can I send this to MegaStumbler for a fix? Any help would be greatly appreciated.

[Mega Stumbler]

The 1/4 is usually a result of vibrations or a mechanical bind somewhere. I don't think disconnecting everything except the tail motor is an effective method to troubleshoot the problem.

There are a hundered possible causes of vibs and binding but here are the most common.

1. Check to see if your main shaft is cracked. Grab the head and the main gear and twist. If the shaft feels springy and twists at all then it is bad and should be changed.

2. Make sure your main gear is alligned properly and is not damaged in any way. Replace if needed.

3. Check your feathering shaft for bends. Remove it and roll it on a smooth flat surface. If it is bent then replace it.

4. Make sure your main blades are not badly damaged and balanced. Repace/balance as needed.

5. Make sure your tail motor shaft and prop is streight and undamaged. Replace as needed.

6. Make sure your main motor is not worn out. A bad bushing causes a current draw that will cause a momentary tail blow out. This is usually presented with an audible sound when the tail kicks uncommanded. Replace main motor as needed.


The 1/4 turn is rarely a 3 in 1 issue. There is usually a mechanical issue that causes the fault. Hopefully these items will help you find the fault.

[UKHeliBob]

Originally Posted by CrazyComi

I have been enjoying my mCP X and have about over 50+ flights on it. This weekend I had a crash while backwards flying and after repair of the cracked tail boom I started noticing that my mCP X does involuntary 1/4 turns to the left now. After going through the forum and looking at possible solution nothing worked. I disconnected everything to the 3&1 board and the only thing that I left connected was my tail and it still has the issue. So is this mean I damaged my 3&1? Can I send this to MegaStumbler for a fix? Any help would be greatly appreciated.

The V2 quarter turn problem is usually to the right but you say yours is to the left and started after a crash so the cause is likely to be different from the 'normal' V2 one. I agree completely with the checks suggested by Mega Stumbler, but if the problem occurs with only the tail motor connected then most of the possible mechanical causes have been removed. When you say that the problem occurs with only the tail connected how does it show itself ? A turn to the left would normally be caused by the tail motor cutting out.

I would think that the most likely cause is a bad connection of the tail wires somewhere which would cause the tail to lose power and would explain the left turn. The clue may be that the problem started after a crash whilst flying backwards causing a cracked boom. The first thing to check is that the tail motor plug is firmly in its socket and cannot move. Did you replace the original silicone on the plug/socket ?

[CrazyComi]

No I didn't replace the silicone but did check the tail connection. It's plugged in as far as it can go also I used my brand new spare tail and It does the same thing. It turns to the left only. I took everything of the Heli, it's only the frame, board, landing skid and tail. So that's why I think it's some kind of a problem with the board.

[UKHeliBob]

You must have moved the silicone in order to plug in the new tail wire so what is holding the plug/socket together ?

[CrazyComi]

I am not sure what you mean, the socket is still with the silicone plug. I just plug the tail wire in to that plug technically nothing is holding it together. Should I drip some silicone over the two plugs after I plug the tail in?

[UKHeliBob]

It probably won't make any difference, but the silicone sealant is designed to help hold the plug and socket together. So, when you unplug them it is normal to remove the silicone and replace it after plugging in the new tail. I use hot glue instead of silicone. If you do remove it be careful not to remove any components from the board with it.

[CrazyComi]

I will try that after I get home, hopefully that's my issue. I also been looking at replacement boards and they are all back ordered everywhere I looked. Might end up with another mcpx.

[RedOctobyr]

Your 1/4 turns are tail-to-the-left, or nose-to-the-right? You just said left, so I assume nose-left, but just wanted to ask.

[d12bn]

Try rebinding

[CrazyComi]

It's tail left and nose right, I also rebinded with no luck.

[Ampdraw]

Originally Posted by CrazyComi

No I didn't replace the silicone but did check the tail connection. It's plugged in as far as it can go also I used my brand new spare tail and It does the same thing. It turns to the left only. I took everything of the Heli, it's only the frame, board, landing skid and tail. So that's why I think it's some kind of a problem with the board.

When referring to rotation the common way is to speak as if you are in the heli, or plane or car. So you're issue is turning right.

With no main blades or head on your heli it cannot turn nose left. This is done by reducing the tail thrust so that it is less than the torque force of the main rotor. With no rotor you have nothing to use to make the heli turn nose left. The tail motor doesn't reverse direction.

If with the mains fitted you still have a nose right 1/4 turn issue (when the heli is in the air) go through Mega's list. Almost definately then a vibe problem.

Amp

[UKHeliBob]

https://www.helifreak.com/showthread.php?t=410466

[CrazyComi]

Ya I meant my tail is turning left and nose goes right. I do think it is any of the parts causing the problem. The list was main shaft, main gear, feathering shaft, main blades, main motor and tail boom and tail blades. All of these parts are not on the Heli so they cannot cause a problem. The tail boom and tail blades are brand new. The problem is still there.
I am getting a bit frustrated with this issue. All I want to do is just to fly the damn thing after a long day of work.
I really do appreciate all of your guyses help though don't get me wrong. On the bright side Amp looks like you just sold an mcpx to me I will just use this one for parts I guess.