mCPx: Known issues, fixes, information rollup

[Finskeeper]

I don't believe this has been mentioned before, but I also believe the landing gear is pretty weak (like the mSR). Not necessarily from hard (or premature) landings, but also from the lateral forces of inserting batteries, plugging/unplugging, and taking them out.

For breaks--- easy fix is to wrap some black thread on each side of the break and coat it with CA.

[ckim]

I also have experienced the issue where the heli vibrates at certain pitch/throttle values. Turns out that my main gear had slid down the shaft a fraction of an inch.

[jorgy23]

The only thing that I have noticed about mine is the clearance between the the motor and the main gear is really tight. I mean almost hard to turn by hand tight. I've tried loosening the motor mount screws a little bit and moving the motor around but it doesn't look like there is any adjustment there.

Anyone have any ideas?

[Mojappa]

The tightness is from the motor magnets, not the mesh. If you look closely you can see that there is the proper amount of lash between gears.

[jorgy23]

Oh, Cool. Thanks. This thing is a tank IMO. I've crashed this thing hard several times now with no serious damage. Gotta learn how to 3d some how. :-)

[shock]

Originally Posted by Atlas

I got mine today. Awesome little thing!!! So I went and tightned everything up. Everything was fine out of the box, which by most reports here, it was suprising! After a few flights and a few crashes, I decided to check the bearings.

Well, the feathering shaft just didnt want to come out. The screws were too tight. Becasue of this I broke the head off the screw. I have spares coming tomorrow, but I am bummed et greatful that thats the only thing.

Remember that these things are so small to take it easy when trying to uscrew the screw!

I feathering shaft only has one screw, the phillips head. The other side is molded into the feathering shaft. I'm ticked, mine shattered when I took it apart. Horrible, horrible idea to have a molded "slotted" end on a feathering shaft, it's a problem waiting to happen. I'm looking for a better feathering shaft with screws on each end, this is what I am accustomed to with CP heli's.

[Thrashaero]

These are the bearings to use. PN#: 203250 from Readyheli. They're much more robust than the Align 681x bearings. They're good for modifying the tail on the earlier versions of the tail setup for the T-Rex 250 due to their lack of play and therefore prevention of leverage of moment arm from the blades tilting as well as taking out a ton of play in the mixer arms of the T-rex 250. They cost more per bearing, at $2.50 vs. 1$ for the align ones.
They do wear out over time of course.

Originally Posted by mediclavina

I also want to know the answer to this question. I'm going to use bearings from my GAUI 200. Here's a picture:

[shock]

Epic fail on the feathering shaft IMO. If the solid end was ony a phillips design it would help 200% in strength lol.

Since I snapped of one of the "ears" with a screwdriver, loosening it, I wonder the chances of it shattering or possibily bending under centrifugal force. That would send the grip a' flyin' for sure. Compared the grips to my trex 250 and they are roughly the same size! (trex is slightly longer) but the trex feathering shaft is like 4x the size of the mCPx, with a screw on BOTH sides!!

Also tried to use 4 step washers but the shaft would need to be 1mm or so longer for that to work.

Please listen horizon, or micro heli, or generic CNC manufacturer!

With that out of the way and the repair done, I've hovered it through a couple more packs with an OEM feathering shaft installation and learned the handling better today, I am really liking this heli. I agree with others, it does not have raw brushless power to dump the collective full down to full up, but like the mSR is just needs simple careful inputs to perform pretty well.

BTW the mSR tail/motor/fin looks identical to to this except the mCPx boom is about an inch longer, may need to try a boom on my mSR

[deviantspeed]

Well I got mine last night and did two flights.... good but not good like the LHS guy was talking about. There's a little slop in the blade holders.

I saw this and other threads talking about the issues, and didn't know what to do. LHS guy called me this morning and said to come in, as he had a fix that he's tested and it's known to work.

Let him do his magic, and she's flying much tighter than before. I feel much better about the new purchase, but I'll still be taking things apart and be checking about every two flights.

WOW, this is truly an amazing bird! It makes me want to convert my 400 and 450 to flybarless setups now!

[Keith C.]

Originally Posted by RoyArms

"move the trainer switch, the swash plate will move up and down to confirm the helicopter is in computer mode"

This should really say throttle hold switch...

Thanks! That was confusing.

[Keith C.]

Originally Posted by deviantspeed

Well I got mine last night and did two flights.... good but not good like the LHS guy was talking about. There's a little slop in the blade holders.

I saw this and other threads talking about the issues, and didn't know what to do. LHS guy called me this morning and said to come in, as he had a fix that he's tested and it's known to work.

Let him do his magic, and she's flying much tighter than before. I feel much better about the new purchase, but I'll still be taking things apart and be checking about every two flights.

WOW, this is truly an amazing bird! It makes me want to convert my 400 and 450 to flybarless setups now!

So what was it the LHS guy did!?

[deviantspeed]

Originally Posted by Keith C.

So what was it the LHS guy did!?

He's cutting custom brass tubing to go between the bearings. The theory is that there is too much of a shear force laterally on the bearings, and it's a flaw with the design.

Think about it. Why the gap of no metal in the blade grip holders? This is very unlike modern designs with other models like 450's and the like.

I'm going to order a set of the bearings mentioned here, just to have spare parts in hand. (flying 450's, I keep a ton of parts with me just in case of a crash) I think there are two issues if I have skimmed the thread for the most important items.

1. Bearing failures.
2. Rotors coming off.

I'm not sure this would solve 1 but it might be related; however the side loading would be potentially reduced. I play an engineer by day at my real job and this seems like a better design. He's contacted HH and discussed this fix. He was having the issues, but has a bird with this fix that's been running with a ton of hours from what I have surmised from conversations with him.

If I have a failure, I'll be quick up here with detailed pics for sure!

[ken6881]

I had the feathering shaft come loose and sling the blades off into my face.( I was landing it in my hand). Other than hurting a little no serious damage.. I recomend putting loctite on it from the get go.

[deviantspeed]

Originally Posted by ken6881

I had the feathering shaft come loose and sling the blades off into my face.( I was landing it in my hand). Other than hurting a little no serious damage.. I recommend putting loctite on it from the get go.

Be very careful and only use a little removable loctite on the screw if it's needed. You don't want it to bleed into the bearing surfaces, that could cause major problems.

This bird spins fast, any advice for a 450+ should be heeded here!

[u8at711]

I'm having a left to right shake or wobble. any cures for that ? only 2 charges flown so far, no crashes.

[col]

your lucky you didnt lose an eye, 3600 rpm plastic blades would do that.

[Heli-Yeah!]

I think that the longer tail boom is not up to the task of enduring many crashes. I have split, and then repaired my first tail boom only to have it later break off at the frame. I have put tail boom supports on my mSR to give it a grown-up look, but on the mCP X I think it could be a viable option as far as offering structural support, as well as minimizing tail vibration which is critical for all gyro systems. It also seems that HH has placed the canopy mounting pins in a spot that prohibits us from repairing them by drilling/melting a hole in the original pin location and inserting a CF rod through the mainframe, like many including me have done with the mSR (which turned out to be one of the better lightweight beef-up mods for it, IMO).

[rew-7]

For you all wanting a proper FS with screws at either end the one from a Walkera 4G6/G3 4G6s is a direct drop in. Screws have more thread too.

[bradharvy]

Originally Posted by bryan_mccombs2001@yahoo.c

Has any one noticed alot of servo noise on the mcp x when it is just sitting?

yes. I actually posted a comment on this. My heli HOVERS just fine, but very noisy- buzzing sound from servos I think... I want to also know if this is common, Just got it 12 hours ago!

[Jaydawgx7]

Yesterday, I flew my mCP X and everything was fine. Stable, smooth, no issues. Today, go and turn it on, and the controls are all messed up. Aile, and Elev controls, D/R, work fine. However, when I spool it up and increase the throttle, the pitch is reversed. When I press the trainer button, it instantly pushes up the servos to full PIT every time I press it. Anyone have any ideas??? Tried to re-bind to no avail.