BASIC CX2 DISASSEMBLY GUIDE

[Patriot Front]

Here's a quick guide to basic CX2 disassembly:
Note: Have your parts diagram handy.

1. Remove the landing skids, the 2 body rods, then pull off the 2-piece body. The rubber grommets should remain on the body. Remove the 4 screws that secure the battery cage to the frame, then pull off the battery cage.
2. Remove 2 screws on the flybar hub, pull off the top crown, then remove the flybar. Pull off the flybar linkage from the upper rotor blade.
3. Remove 2 screws on each pair of rotor blades to pull them off. Remove the swash linkage (2) from the swashplate.
4. Remove 2 screws on the inner shaft retaining collar (bottom of heli). Then pull off the retaining collar & inner shaft main gear.
5. The upper head & inner shaft will then come free from the core. Pull off the bearing holder from the main shaft too. Note: There is no need to remove the upper head from the inner shaft unless you need to replace one or the other. In that case, there is a single 1.5mm hex set screw that holds the upper head onto the inner shaft. It will take some effort to remove the head so twist as you pull.
6. Remove the 4 screws from the lower head & pull it upward & off. Removing the lower head will be difficult the first time because of burrs and Locktite from the factory. Twist as you pull it taking care not to break the 2 pins that the blades attach to.
7. Disconnect the swash assembly from the servo arms, then pull it up & off.

This is as far as you need to make basic repairs or upgrades. At this stage, you might consider getting an aluminum lower head, heat sink, & top bearing holder. The aluminum swash assembly is a must. (E-flite only for core components, NOT Microheli). Microheli makes a decent aluminum frame, but the their swash & lower head are garbage, IMHO.


Basic Dissasembly Continued:
To replace the outer shaft or outer shaft main gear, continue below:

8. Remove the single screw on the outer shaft retaining collar, then pull it up & off. Note: The beveled edge of the retaining collar will face downward.
9. Carefully push the main shaft downward until it comes free from the main frame.
There are 2 bearings that secure the main shaft to the frame tower; one on top, & one on the bottom. The top one may remain with the frame when you push the main shaft downward & out. If they come free from the frame, they will be visible on the main shaft. You can remove them from the shaft, or keep them in the frame tower.
10. There is a step washer in the bottom portion of the frame that belongs under the lower bearing (outer shaft). The step edge of the washer will point upward. This washer may naturally remain inside the frame tower.
11. The lower bearing for the inner shaft will be secured inside the outer shaft main gear. Removing the main gear from the outer shaft is not necessary. If either is damaged, the replacement part is sold as one piece.
12. Your lower inner shaft bearing is also integral to this unit. Your 2nd inner shaft bearing is inside the bearing holder that you removed in step 5. These 2 bearings are the smaller pair compared to the outer shaft bearings.

Things to watch out for when putting it all back together:

A. Make sure that the outer shaft retaining collar is pushed all the way down onto the frame tower with the beveled edge facing downward. Spin it as you push it downward until it rests directly on top of the frame tower. Meanwhile, make sure your outer shaft gear is pushed all the way upward.
B. If you can't push the collar down all the way, remove it, then remove the main shaft from the frame. Now place the retaining collar on the shaft and work it all the way down. This may be difficult at first due to burrs on the shaft from the factory. Once you can freely push the retaining collar all the way down the shaft, remove the collar from the shaft, then place the shaft back into the frame. Remember, 1 bearing goes in the top of the frame tower, the 2nd goes in the bottom; then the step washer goes underneath the lower bearing with the step facing up.
C. Now, with your index finger pushing down on the retaining collar, use your thumb to push upward on the outer shaft main gear. Pinch hard, but not too hard. Use your other hand to insert the single screw on the outer shaft retaining collar. That screw must be extremely tight. IMPORTANT: DO NOT REPLACE YOUR SWASHPLATE & LOWER HEAD UNTIL YOU ARE CERTAIN THAT YOUR OUTER SHAFT RETAINING COLLAR IS SECURED IN THE PROPER POSITION. Push & pull on your outer shaft to check for any vertical play; if there is play, your retaining collar is too high, meaning you didn't push your core together hard enough. Spin it with your fingers to ensure it spins easily; if it grinds, your retaining collar is too low, meaning you pushed too hard.
D. Oil your new swashplate assembly (top & bottom) before installing it. Use Tri-flow or Dry Lube. This is a crucial component for steady flight.
C. Make sure your lower head is replaced exactly in its original position. There are holes in the outer shaft to recieve the 2 upper screws, and strike marks on the shaft where the lower screws were.
E. Ensure that the holes on the inner shaft main gear are lined up with the flat edges of the tip of the inner shaft. The inner shaft retaining collar must fit over the gear with its holes lined up with the holes on the gear. The 2 screws on this retaining collar must also be very tight.
F. When your core is reassembled, push & pull on the upper head. There should be ZERO vertical play on your inner shaft when doing this. Test the outer shaft in the same manner by pushing & pulling on the lower head. If there is more than 1mm of vertical wiggle room with your core, you will need to disassemble it and start over.
G. Spin the shafts with your fingers to ensure that the gears turn smoothly with no excess friction.

Identifying any problems or mistakes at this stage will save you time & grief when you attempt to fly!

[Patriot Front]

[rovpilot26]

Very nice breakdown....

For those of us who are the visual type...

[meisterpbk]

Very Helpful Patriot! Thanks for taking the time to put this together!

[Tom.C]

nicley done.

I don't know about any one else but ive found adding an extra washer between the two main gears helps to pull them slightly further apart, because i noticed that the gear on the outer shaft was able touch the motor powering the motor that turns the inner shaft, although i had put a pair of AFC motors on so perhaps the pinons are in slightly out of place. after the washer it seemed to run little quiter too.

[Johnk518]

Stupid question. . . how does one remove the inner shaft main gear? the retaining collar is off. But I'm having a hard time removing the gear itself, its like its glued on.

Help would be appreciated!

Nevermind, it took a firm but gentle hand. I just didn't want to damage the teeth.

[AndreSmith]

Patriot -

Thanks very much for the detailed and useful pic. I have a question - you show the Lower Rotor Swash Linkage with the smaller oval on top. On my CX3, they are installed in the opposite direction, small oval on the bottom. Does it make a difference?

Andre'

[Skyranger]

Yes, small oval on top, reason...travel of swashplate, up and down. Speaking of the SP..I have noticed that you should inspect it daily just to make sure that it for some stange reason it has not separated. That happened to me and for 2 days, I kept adjusting my servo arms up and down never keeping it in tune.. then I saw where the SP had separated, since then I've had no more problems. When you get the SP perfectly adjusted it will take off and hover with just one hand on the throttle...amazing Dave

[Philup]

Thanks for that great info and diagram Patriot. Just recently purchased a CX3 and then ordered about $170.00 of aluminum upgrade parts. This should prove to come in very handy.

Originally Posted by AndreSmith

Patriot -

Thanks very much for the detailed and useful pic. I have a question - you show the Lower Rotor Swash Linkage with the smaller oval on top. On my CX3, they are installed in the opposite direction, small oval on the bottom. Does it make a difference?

Andre'

That’s odd as mine are as pictured in the diagram, small on top.


~Phil~

[Laserdave]

I had to take my bird apart the other day and now I'm reassembling and the inner main gear and outer main gear seem to be touching. What seperates the two ? The outer main gear has the step washer seperating it from the frame. Maybe my inner shaft is not set right ? What holds that in place ? It seems like the inner retaining collar would, but what keeps the inner gear from touching the outer gear ?

[Midnight_1982]

There should be another bearing that sits withing the bottom of the outer gear. then the innershaft gear presses against it.

[Laserdave]

Thats what I kinda thought too, but I dont see one in the diagram on this Thread.

There looks like there is one on the official blade cx2 manual exploded view, but that has no part number associated with it so I'm at a loss.

[CrashCanuck]

You need the bearing in the bottom of the outer shaft gear. And like someone else stated if you need more clearance from gear to gear add a step washer. I have the MH carbon and alum. frame and I have 3 washers shimming the gears down away from the frame or they rub slightly.

[WH1_T-type]

Originally Posted by Laserdave

Thats what I kinda thought too, but I dont see one in the diagram on this Thread.

There looks like there is one on the official blade cx2 manual exploded view, but that has no part number associated with it so I'm at a loss.

It's the same bearing as the ones that go into the guide and bearing holder at the top of the outter shaft. That is why it isn't numbered. In the color break down in the first post though it is labled.

[Laserdave]

Got it !
Thanks to all.