So you just crashed your mCP x... (things to check before flying again)

[markj99]

Originally Posted by swizzie535

I have an mSR and 450 but for some reason I cNT FLY THIS mcpx----AS SOOON AS IT STARTS TO GO UP IT WANTS TO TIP OVER----I DONT GET IT,

Your bird may well have other problems; but because this is a flybarless system, the DVD that comes with the heli emphasizes that you must not diddle with the sticks during takeoff.

It's my understanding, that if you give control inputs while it's on the ground -- where the heli can't respond -- the gyro/s keep increasing their action, trying their darndest to reflect your wishes. Then, as soon as you clear the ground, they've over-corrected and you get flip crash and burn.

[duceduc]

Originally Posted by questerng

Hi,

Does anybody has a tail hunting problem.. Even out of the box.. There is this little hunting.. after awhile.. the tail drift left..

Did my Flip attempt today.. Crash of cause.. Done everything that's possible but now after the crash.. it's more obvious..( Ive check everything that's mention.. even re-binding it) and there is a vib..

Can it be the throttle and rudder relationship.. I've got my Travel Adj at 130 both side..

Oh... the other thing is the blade is not tracking straight now.. after the crash.. can it be the servo screw came loose.. I've check seems to be ok..

thanks
Q

I, too, am getting this tail drift right out of the box. Did you ever fix it or know the cause? I have a V1 btw.

[questerng]

Originally Posted by duceduc

I, too, am getting this tail drift right out of the box. Did you ever fix it or know the cause? I have a V1 btw.

Hi,

gone pass that already.. Its a vibe issue..

so My suggestion is to trace where the vibe is.. some screw might be loose or your main board may be loose..

even if the tail is loose it will twist.. and that will also cause hunting of the tail..

hope this will help..

Q

[duceduc]

questerng,

Thanks for the reply. I have fix my issue as well. It turns out the wow brushless mod kit pnp was giving me problem. I have re-soldered the rudder pins and the motor (yellow wire) pin straight to the pcb.

[chuteopn]

Swizzie
I had the same problem, right out of the box.
Mine ended up being a burnt servo, right front.

[arfermo]

I had the same problem. Mine turned out to be elevator and aileron trims not centered on a DX6 tx. Hold the heli in your hand [carefully] and slowly bring it up to take off revs. My swashplate started off level and tilted noticeably as the revs built up. Also, out of the box the blades are very loose. I tightened mine up slightly with no illl effects Hope this helps Arf

[k.gordon1120]

check feathering shaft they bend easy

[daveapplemotors]

If the battery moves back or pops out. Or the skids come loose. It can strain the battery wires at the solder joints on the board. If canl break a wire eventually.
When I destroyed my hollow stock boom my battery moved quite a bit. On kitchen floor test flight after refitting a solid boom she fell as soon as she got air-born. No blue light. White power wire was broken from the board. Give a little tug and if it comes loose then it wasn't working too well anyway.

I used a 1mm drill and to remove solder and refit the wire. Drilling through makes soldering very easy.

Even if you are very careful to pull only on the battery and connectors you can have power wire failure at the board. Rolfey warned us. Thanks Dave.

I have been very careful to pull only on the connector when removing the batteries. But I my crashes alone have strained those connections.

[intelligencer]

I had a more serious blade strike against a metal object today and had vibrations afterwards that were present intermittently for the test flights I did looking at all the usual things. main shaft, linkages, tail, feathering shaft etc.

I ended up taking off the elevator servo to see whether my pots were dirty. Minimal marking and I've put about 30-40 flights on this since new. Had one other serious crash but no real damage from that.

After losing a small screw and finding it with a magnet trapped in the wiring loom of the small heli I reassembled the servo and I noticed what was the obvious cause of my problems...

After the last serious crash my stock blades had become a bit tatty so I had changed to the supplied bullet blades.

What I noticed is that the small metal weight in the bullet portion underside on one blade was missing.

I squeezed the other sides counterweight out too and put the blades back on.....

No more vibrations.

[macem]

... test the torsional stiffness between rotorhead and maingear by gently (!) wringing it against each other...

.... there should not come out an angle of more than five degrees or so ... otherwise the shaft is broken or splittet - what is hardly to be seen at the black cf ... but causing retarding reaction to stick-moves or unflyability at all...

macem

[BrettOssman]

Can your swashplate actually become unlevel due to a crash? Seems odd, unless something broke, but I am a newbie, so could EASILY be wrong on that. Do they just gradually become unlevel with more flights? I had my swashplate looking good, by eye mind you, but today it was significantly off. This probably explained some unusual drifting issues I was having.

Now, I am leveling while the heli is OFF, then zero-pitching at midstick (which is set to 50). Is that correct?

FYI, went through the checklist and all seemed good except for the swashplate being unlevel.

Thanks folks

[cptozzy]

Originally Posted by Stevin

personally two things I have missed after crashing and then realized was

one: The swash plate pops out of the anti-rotation bracket. The heli will still fly but will not fly correct. This happened to me on atleast 4 occasions. Once I realized and popped it back in all was good.

two: Make sure the main motor gear is pushed on as far as it can go. I experienced this first hand and couldn't believe the difference in climb rate that the tiniest adjustment inward makes. If you notice that you have the thottle pumped to 85+% to gain hover this is most likeley your problem.

Ditto - Especially the main gear being seated. Even without a crash I routinely re-seat it every 5 flights or so. pop off the landing gear put your thumb(s) at the apex of the main shaft above the blades, grip the main gear with both index and middle fingers and speeze it together. a couple mm of main shaft should portrude out the bottom.

[KSHeli]

I didn't know where else to post this.
I crashed my mCPX today and broke both of the front canopy mounts. Started on repairs and noticed a single magnet wire coming off of the main boards lower right side (as facing from the front of heli) and is wrapped around the canopy mount. Question is where is it suppose to go, it was located like it may have been attached to the aileron servo board? I couldn't find any evidence of where it was attached.
Its a version 2 mCPX with the following mods, metal head, swashplate and an extended tail.
If someone could maybe provide a pic(s) it would be appreciated.
Jim

[MyRCode]

That's the antenna... Does need to be attached to anything else.

Sent from my EVO using Tapatalk 2

[KSHeli]

Thanks, hadn't thought about the antenna.

[Chappyy]

Originally Posted by BrettOssman

Can your swashplate actually become unlevel due to a crash? Seems odd, unless something broke, but I am a newbie, so could EASILY be wrong on that. Do they just gradually become unlevel with more flights? I had my swashplate looking good, by eye mind you, but today it was significantly off. This probably explained some unusual drifting issues I was having.

Now, I am leveling while the heli is OFF, then zero-pitching at midstick (which is set to 50). Is that correct?

FYI, went through the checklist and all seemed good except for the swashplate being unlevel.

Thanks folks

If a servo push rod bends it will change the swash level.

[TucsonHeliMike]

Originally Posted by Mojappa

Just wanted to make a quick checklist of things to check after any crash, similar to how the guide pin would pop put of the AR bracket on the MSR, there are a few key areas that take the impacts.

• Make sure the linkages are attached to the grips and the swash, this is a common "break point" to save other parts from damage.

• Check that all three servo links are still attached to the swash and that there aren't broken balls on the swash as well.

• Another designed impact absorbent is the main gear spinning and sliding down on the shaft. First make sure the "D"'s are keyed into each other, mine seems to spin and come down at the same time. Hold the grips and spin the gear until the flat spots line up, then with one thumb on top of the mainshaft, using your fingernail press the gear back up into place, there should be about 1/16" of the shaft sticking out below the gear. If your heli suddenly requires more collective than usual to lift off or vibrating this is likely the culprit.

• Check that the grips don't suddenly have any side to side or excessive up/down movement as this could be an indicator of a bad or failing bearing. It's a good idea to feel this when it's new to get an idea of how it should feel.

• Check your tail rotor for the white stress marks around the middle, it gets bent fairly easily and will lose it's ability to hold, especially on punch outs, if it's got the marks its best to just replace it. While you're back here gently flex the tail boom to check for splitting, this can be fixed with CA if it does start splitting.

• Make sure the battery is pushed in fully otherwise it will offset the CoG.

• Check to make sure the landing gear is fully pushed into the mounting holes and none of the struts are broken, though so far this gear seems tougher than my mSR's was.

• ALWAYS RETURN TO NORMAL MODE AND COLLECTIVE IS FULLY DOWN BEFORE DISENGAGING THE THROTTLE HOLD. Accidentally spoiling up sucks and reminds you really fast that this is a serious toy, capable of causing more damage than similarily sized Blade helis. (see next post for more info on this and some peace of mind)

• If you've gone through this list and the heli still won't fly right (shakes, shimmies, or is just random in it's response to inputs) check that the little brass looking "keepers" on top of the servo shafts aren't loose and allowing the shaft to move up and down freely. They are threaded on this (MSR's were press on) so you can take some tweezers or small needlenose pliers to tighten them back down. I don't think this is likely to be caused by a crash, at least not a single one, but if all else checks out and it's still not flying right then this is another area to inspect for play.

• Still not right? Two more things. The feathering shaft/spindle could be bent. To check for this remove one blade, preferably the one on the phillips screw side, and use the screwdriver to turn the shaft clockwise (so as not to inadvertently loosen), the other blade should remain stationary, if it makes a circle when you turn it then the shaft is bent.

• All of this hasn't helped, eh? As a last resort per Finless Bob, try rebinding it. His had a performance issues that he couldn't track down and they went away immediately after rebinding.

• If you're still getting a vibration after all of this and you've got a decent amount of stick time on it (40+ flights) you may want to try ChrisH's tip of cleaning the wipers and plate behind the servo. Here's a link to his thread.
https://www.helifreak.com/showthread.php?t=289666


Once it's deemed to be okay then return it to a level surface and prepare to fly again. This heli takes more attentiveness than the MSR and the like. They're more sensitive to being improperly setup (or tweaked in this case) and have the potential to cause much more injury and damage than FP's with lower headspeed. If you're ever unsure of your heli or the way it's acting then immediately power down and diagnose and/or post your problem here for assistance. A slight wobble on a MSR was annoying more than anything, a wobble on this could lead to much more than irritation. I can't stress enough to be safe with these little guys and treat them as if they're a 700E, it may fit in your hand but it's risky to lift off from it. It's small size gets people off their guard thinking it's not potentially dangerous, it can be.

Also, doing a preflight is something you should get in the habit of, especially if you are going to move to bigger birds. I made a habit with the SR to attempt to tighten every screw on the heli before the days first flight. Doing this can bring a problem or possible malfunction-to-be to you attention and save you unecessary damage. You should also, before spoiling it up, check that the cyclic servos are all functioning properly.


***ADDITION***

I'm sure it'll end up in it's own and in other stickies but here is a link to the Finless videos on the mCP x. Lots of great info there regarding Tx and heli setup.

https://www.helifreak.com/showthread.php?t=289344

+1 on all of these. one mentioned in the following posts (that might be good to add to the first post?) is to check the main shaft for cracks, which are hard to see. This caused weird tail issues, like 270 degree spins on spool up and tail 'hunting' in flight, and moderate vibrations starting about halfway through a 4 min flight. Checks include the mainshaft being more flexible when turning the main gear while holding the blade grips (such as when reseating the main gear), and (once removed) inserting a toothpick somewhat gently in the blade grips end of the shaft, which will make the cracks apparent. Mine was cracked halfway down the shaft on both sides. A little CA and some sanding to get the shaft to fit back through the bearings and it was good as new again; the tail behaved and no vibrations. Not an intuitive solution, but nevertheless it worked.
Love this forum, would never have figured it out without you guys.

[Alignment]

My mcpx just lost most of its negative pitch for some reason, any ideas?

[Bornwithatooth]

Originally Posted by Alignment

My mcpx just lost most of its negative pitch for some reason, any ideas?

I think mine just did too
Checked everything, and only found that the main gear had sipped down a tiny bit on the shaft. Pushed it back and still don't think I see as much neg pitch as I had before. I am seeing a bit of chatter on the right servo, and there seems to be alot more slop in my dogbones and servo linkages (Paciently awaiting o-rings right now). My guess is that I've put about 50 batteries through this thing.

Born

[Bornwithatooth]

Originally Posted by Alignment

My mcpx just lost most of its negative pitch for some reason, any ideas?

I think mine just did too
Checked everything, and only found that the main gear had sipped down a tiny bit on the shaft. Pushed it back and still don't think I see as much neg pitch as I had before. I am seeing a bit of chatter on the right servo, and there seems to be alot more slop in my dogbones and servo linkages (Paciently awaiting o-rings right now). My guess is that I've put about 50 batteries through this thing.

Born