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NX4 Discussion and support of the Gaui NX4 Nitro Helicopter


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Old 12-16-2012, 07:18 AM   #1
adam crosby
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Join Date: Jun 2007
Location: Japan
Red face NX4- Please read

I like Gaui and I like other brands too, I have both Gaui and Align. I have a brand new Align 450 Sport V2 under the christmas tree and I cannot wait to open it on the 25th! This is my second Align; the first one was a T-rex 450s and the motor pinion snapped on the second flight! But those 450xl motors were known for that problem. The original thread from 5 years ago is below.

http://www.helifreak.com/showthread....ht=adam+crosby

However, please remember all new 1st release helicopters have problems just like the Nx4 tail slider problem. I have been reading about the problems with the tail pitch slider, and this is a shame and not acceptable. I am NOT starting a battle here but please remember that all 1st release helis have problems. The important thing is that the manufacturer, in this case Gaui, fix these problems. According to JC, the newer kits come with the tail slider unassembled thus removing the possibility of overtightening.
I found some similiar problems with some other very good brands and pasted them below together with the NX4 issues. Every heli has problems when first released and I do feel for people with the tail slider issue, and am confident things get better. I am planning to buy one in April.
I am NOT trying to compare helicopters and brands here but I would like to hear your thoughts.
Regards,
Adam


SAB Goblin
Boom and blade clearance issue.


Align T-Rex 700 E

Problems and Solutions Summarized --------------------------------------------------------------------------------

It's a start but so many things are being repeated thought it was worthwhile.
If someone knows how to paste an outline format I am all ears.



1. One Way Bearing
a. Known to spin the steel insert inside the hub. At the factory this is secured with green loctite.
b. Solution is to scuff the inside of the autorotation hub with fine sandpaper and the outside of the steel insert then apply Locktite #620 Sleeve Retainer.
c. Best Solution is to drill and tap a 3mm set screw in the autorotation hub that tightens up against the steel insert. Also dremel a groove into the steel insert so the set screw does not all it to rotate.
d. http://helifreak.com/showthread.php?t=277444

2. Vertical Play in Main Gear
a. Caused by the bearing in the top of the autorotation hub getting pushed down in the assembly.
b. Solution is to apply heat, remove it and secure with Locktite #620 Sleeve Retainer.
c. (Note) The green locktite in the kit is Thread Retaining compound and not suitable.)
d. http://helifreak.com/showthread.php?...=vertical+play

3. Main Gear Stripping
a. This is especially prevalent with the original stock gear, Align revised the gear with a CNC Gear (AGNHN7019B) in the newer kits that seems to hold up well.
b. Solutions
i. Align 115T CNC Gear – Should be good for the Align Motors(470, 510, 530kv)
ii. Align Slant Gear(H70021) and Pinion – Good results reported with high power setups, Scorp 4525 Ltd, KDE 1917. Be aware that this gear puts axial loads on the autorotation hub and motor. Debate exists around resting the pinion on the counter bearing block to remove this force from the motor.
http://helifreak.com/showthread.php?...ight=gear+mesh
iii. MD600 110T Herringbone Gear – Still too new to tell, but good results so far. Since this gear rides 1mm from the frames necessary to dremel the frames for clearance. Available from http://www.topshop.com.tw/md-rc-en/p...1-74F015BA80DE
iv. http://helifreak.com/showthread.php?t=277444

4. Mesh
a. KDE Adjustable Motor Mount is pretty much a requirement for adding another motor or gear. A worthwhile investment as setting mesh is important.
b. Setting Proper Mesh and ensure counter bearing is lined up.
i. Put motor and mount in first
ii. Set Mesh using paper method, counter bearing screws loose.
iii.. Tighten motor mount bolts
iv.. With pinion support loose, spool it up to center counter bearing.
v.. Tighten Counter bearing bolts
vi. Adjust pinion height. I adjust leaving paper thin space between counterbearing and pinion to allow for heat expansion.
vii. Added note: Remember if there is play between the screws that tghten the motor to the mount you can have the motor shaft off center side to side(between frames,). Solution is to leave these bolts loose, pinion off, counterbearing in, then tighten the screws and will ensure horizontal alignment of motor.

5. Tail Kicks
a. Can be many things but there are a few areas to look at on the 700E.
i. Governor gain – Too many variables but high gain causes kicks.
ii. In high power moves the stock 105mm blades do not have enough authority, best results are with Rotortech 115mm or 120mm. In this setup a longer tail fin from Custom Heli Parts keeps the longer blades protected. Also using the f3C gear on the front lowers the nose and raises the tail keeping it out of harms way.

6. Tail Rotor Failure
a. The Metal Tail rotor is known to fail and the spindle bolts break off.
b. Solutions
i. The KDE Tail Upgrade, be careful as the KDE link arms can cause binding so you might need ot sand the edges to get it smooth.
ii. Quick UK Tail Upgrade is a nice addition and is proven reliable.
iii. The 600N Plastic Tail grips can also be used, while this seems like a downgrade the tail is smoother that either of the two above options.
iv. http://helifreak.com/showthread.php?...t=tail+failure
v. Upgrade the tail spindle bolts to 12.9 steel. Mcmaster Carr. Not needed with KDE or Quick UK as already 12.9 Steel

7. Head
a. At a minimum you need to remove the grips to grease the thrust bearings. Apply heat to the head to loosen the locktite otherwise very difficult to remove.
i. Can upgrade the spindle bolts to Lynx and they are nice, but not sure if really needed.

8. Balance
a. Heli tends to be tail heavy, so when planning the location of the electronics try and get as much weight in the front as possible. This keeps you form having to move the lipo’s forward and getting a 3rd party solution that allows the lipo frame rails to be extended forward.
1. KDE Front Mount allows battery tray to slide forward. Some issue with the new frame design rails getting in the way.
http://helifreak.com/showthread.php?...r+mount+frames
2. GForce Rail Extender

9. Canopy Mounting
a. Stock system uses C Clips to hold in place. The front mounts do not really need secured it is the back ones that are important to secure.
i. Quick UK has some nice magnetic ones that do not require modification of the stock canopy.
ii.http://helifreak.com/showthread.phpt...hlight=battery

10. Battery/ESC Mounting
a. Basically there are a ton of options so just going to point out some things to watch
i. No more than 12” wire from ESC to Battery total.
ii. Having ESC in back can be necessary because of heat or it just won’t fit up front. unless you go with a Jive.
iii. Lipo Trays

1. Can use Strapping Tape to secure the two lipos together, velcro under the lipo and straps to hold the lipos to the stock tray. The align Straps break, JR or scorpion straps are more robust.
2. http://helifreak.com/showthread.php?...hlight=battery

11. 3rd Bearing Block Modification
a. This is purely optional but benefit is less frame flex which contributes to main gear stripping and an overall smoother heli.. Addition of 3rd block underneath the main gear.
b. http://helifreak.com/showthread.php?...ight=gear+mesh

12. Frames
a. When you do crash the frames tend to break by the elevator servo. There is also a fair amount of flex.
b. Dan at Custom Heli Parts has frames for the same cost as the align frames but they are better for two reasons. One the Carbon is a much higher quality; second the Elevator Servo has been moved to the rear thus strengthening the weak point. Added bonus is his LiPo trays are a nice upgrade.
c. http://helifreak.com/showthread.phpt...ght=CHP+Frames

13. Wiring
a. There are many ways to power the bird and not going to get into all that.
http://helifreak.com/showthread.php?t=237931
http://helifreak.com/showthread.php?...ghlight=wiring

14. Lipo Sizing
a.The capacity and C Rating of Lipo's in this bird comes down to flight style and personal preference. The range can be from 3500mah vs 5000.
http://helifreak.com/showthread.php?...highlight=3000


GAUiI NX4

Tail slider overtightened
Tight canopy
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Old 12-16-2012, 08:07 AM   #2
rstacy
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Join Date: Apr 2004
Location: Rochester,NY
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Quote:
I am NOT trying to compare helicopters and brands here but I would like to hear your thoughts.
Regards,
Adam
Remember, you asked!

First off I have no doubt that if there even is a problem, Gaui will correct it.

Second - When ever there is an issue regardless of the manufacturer, I can never understand the strategy of pointing fingers at the other guys and saying "Look! They have problems too."
It seems to be the standard first line of defense and I just don't see the point.
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Old 12-16-2012, 08:11 AM   #3
Si_B
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Join Date: Sep 2009
Location: West Sussex, England
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A completely pointless post. Sorry mate but do you own a 700e?

What about,

No throttle ball supplied.
Incorrect servo bolts
Model is tail heavy with no room in canopy to fit a battery big enough to counter balance.
Poorly moulded fan.


It's a great model with a couple of things that could be easily sorted by Gaui. I'm sure if I went trolling other Gaui forums, I could find a nice list of problems.

Sorry, but I see no point in what you have posted here. Maybe this should be in the align forum where it could be useful if you own a 700e?
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