Official GAUI NX4 Build Thread

[Matt Nasca]

Originally Posted by apstudio

Hi all,
Will it be correct if I will connect the pressure tube to the bottom hole of the muffler?

Thanks.

As long as it's connected to a pressure port on the muffler, it shouldn't matter where it is... I think

[HelisRock]

Do yourself a big favor and before you start, throw away all the Gaui M3x6 Button head screws used all over the frame sides. They are made out of alumibutter and will strip in a heartbeat once loctited (even if you apply heat they're impossible to get out). I know what you're thinking, trust me, it's not a tool issue. Save yourself a lot of grief and use the Gaui 842025 M3x6 Socket Head Cap Screws, which have much more meat on them, or better yet, use these:

http://www.mcmaster.com/#92832a215/=uebgna

These are silver, not black, but they're a treat to use, especially with this:

http://www.mcmaster.com/#6186a61/=uebljp

[memheli]

Originally Posted by Matt Nasca

If you are using the GAUI Governor or the Align Governor with the Mini VBar AND you're using satellite recivers, you'll need to do this file modification to enable to use of RX A, as the signal input.

http://hf.rob.com/showpost.php?p=4423244&postcount=1

If you're using an external receiver, then this above modification is not necessary.

**This is an at your own risk modification!** That being said, it worked well for me with no issues at all.

Attachment 370590

forgive me for digging up a 4 year old thread..I'm wondering if this is still an issue as t's the setup I am going to use.

[ihamsa]

Fun to install? Yeah, if by fun you mean a sadistic torture designed by an evil genuis, then yes. How on earth is one supposed to install them? I'm out of ideas. Tried oil and... more oil, still no go. Please give more ideas!

[merle1960]

were did you get that

[merle1960]

Originally Posted by Matt Nasca

Thanks guys! I hope this post helps and can be used for a repository of good build info. I'll be adding more later as I have time.

As far as the things that GAUI prebuilt, like the head and tail, they are GAUI tight and smooth as butter. I left mine as is but if you feel better opening it up and checking, by all means do it. It certainly won't hurt. The swash was the only place I found a single ball without threadlock.

were did you get your header tank

[merle1960]

Originally Posted by Matt Nasca

Hey everyone, I wanted to make this build thread to help others planning for the NX4 and/or building the NX4 to have a resource for information regarding the build.

The build is extremely straight forward and the easiest build I've ever done. It shouldn't take more than several hours. I got the airframe together in 2 hours (that includes taking the pictures). I'll be doing the electronics as a supplement to this because I don't have electronics for the NX4 I'm building. I'm going to take pictures of another NX4 that's built and show the wiring.

I'd like to underscore how easy this build is! GAUI built the entire head and most of the tail sections so that was a nice surprise. A couple of small details left me scratching my head but overall, a pure joy!



As expected, the parts came in organized boxes.


Everything is neatly placed in bags. This is where my only real gripe is. I found myself searching bags for a few parts. Not a huge deal because there aren't a lot of parts, but by the time I was half way through the build, I had a lot of open bags spilling parts.


In true GAUI fashion, they have you build one half, then add the other. I like doing it this way, it seems much easier to me.




Make sure you get these in the correct orientation! I know a really good pilot who got the bottom bracket upside down and the bearing came out in flight! Make sure that the bottom bearing faces down and the top faces up!




I really wish the countersunk screws were countersunk better. It doesn't have any effect on anything whatsoever but it's worth mentioning to GAUI for future kits




This guy goes together quick!


Occasionally I had to refer to my trusty ruler for screw measurements. GAUI uses screws that are plenty long for good grip!






Continuing on with the half frame


In the boom clamp (which is upside down in this pic) you can see the screw sticking out slightly, that is there to pin the boom. It presses into the boom and should work very well.




**NOTICE** I put this on backwards, even though I read the directions! lol, it actually goes on the outside of the frame! I didn't catch it until I went to setup the pushrod.




THIS is the correct way!


I like the reinforcement caps GAUI includes for key screws. Plus they look cool!!


Frame built!


This is the cutest little clutch. It's about 50% of the size of a .90 clutch. The liner comes installed.


The gap was set perfect out of the box


I added red threadlock to certain parts I didn't want to vibrate loose, like the set screws on the starter coupling.


The fan assembly mounted to the little OS 37. Another NOTE: Remember my complaint about on bags? Well there is a little slip of paper with a diagram on adding a washer on top of the fan assembly before the nut that locks it down on the crank shaft. I did not initially notice this so I didn't install it. Only after I got done and had spare parts did I figure it out.


Standard looking clutch and assembly


I put the motor mounts on first, it seems easier to install that way. You can use a long allen wrench to secure them vs a angled one later.








Before I get comments about the skids being on backwards.... It's in the manual that way




I took my little pin screws out of the boom supports and CAd them in place. Also CA, the screw in. If you do not, they WILL vibrate out in flight. Thankfully a canopy clip fits the hole perfectly and will work in a pinch.


This was all uneventful. There is a slot in the main shaft that the set screws fit into to secure it. I LOVE this because you don't have to muscle the screws (and risk striping them) down to keep the shaft from slipping.




Here is how the tail comes! Yes GAUI uses locktite and they tighten stuff down very tight. I'll call it "GAUI tight" from now on.


The tail is essentially the same as what is on the X4 & X5 so really nice!! You want to use the outside holes on the tail output shaft.


As you can see they did use threadlock


This has to be the easiest tail to build. There are two set screws in the hub and two link screws and you're done!! I found the tail to be completely smooth even without oil. I put some Tri-Flow on it for good measure.


The head also comes completely pre-built!


The swash does too.


Some had threadlock and some didn't so check them!




The pitch arms had threadlock




When installing the links remember GAUI out!


These little guys have a rubber pad that gets inserted to keep the tank from foaming. They are fun to install


Pluming the fuel line is pretty easy.






SImply screw in the rails and viola!




When you install the muffler pressure port, don't overtighten it. I broke it off and had to extract it. Luckily I had another which I secured with JB Weld.






I put the header tank on with double sided tape and zip ties. The included solution would work but if you want to use that method, you may choose to modify it slightly. For me the zip ties work great.


This little tab helps hold the canopy on. I chose to epoxy it on versus installing it with the included double sided tape. I got the idea from Andy P. Thanks man!


I an using a Mini VBar with Pro. I don't show a picture of this but there is a metal plate that comes with the kit to add mass to the VBar. I used it and in my opinion it is needed with the Minn VBar. I chose to use Futaba 30x30mm pads instead of the 3M tape that is included.






I really like the canopy on the NX4

were did you get yours

[rcwng]

Originally Posted by HelisRock

Do yourself a big favor and before you start, throw away all the Gaui M3x6 Button head screws used all over the frame sides. They are made out of alumibutter and will strip in a heartbeat once loctited (even if you apply heat they're impossible to get out). I know what you're thinking, trust me, it's not a tool issue. Save yourself a lot of grief and use the Gaui 842025 M3x6 Socket Head Cap Screws, which have much more meat on them, or better yet, use these:

http://www.mcmaster.com/#92832a215/=uebgna

These are silver, not black, but they're a treat to use, especially with this:

http://www.mcmaster.com/#6186a61/=uebljp

I agree.... When I was tried to undo all these M3 button heads from the frame half done/started by someone I bought from, they have so much play in them I scared I would strip most of them....

The part is confusing when it uses different driver for M3 button and M3 socket head.... I never know that before....

What about the one on the servo mount where it uses M3x7?

[Edge67]

My local hardware store has them. So if I need a couple in an emergency I swing in and grab a few.

For my normal use I buy them from RTL.

RTL Fasteners - Hobbies, Radio Control, ( R/C or RC ), locknuts, metric screws, servo screws, socke: Metric Socket Head Cap Screws

Greg

[rcwng]

Originally Posted by merle1960

were did you get yours

Hi merle1960. Thanks for the info and pictures. Do you have pictures for the servos? Especially the arms and where you put the linkage balls? I put the balls for cyclics, throttle and rudder facing outside instead of inside. Also they the supplied bolts to install the balls are inconsistent. I got two M2X10 and the rest are like M2X14.... Did you get this as well?

W

[Number]

Originally Posted by rcwng

The part is confusing when it uses different driver for M3 button and M3 socket head.... I never know that before....

That's pretty much normal.

[Helicrow]

Anyone else have problem fitting rx pack because canopy is so tight ? On the top rx batt mount i cant even fit the ultraguard or receiver because then i cant use canopy. If i use the front lower position rx batt mount i can fit a pulse 2550, thats the boggest and its tight enough to cause cracks on the canopy mount holes.

Is it possible to relocate the canopy rear mounts ?

[rcwng]

Holly S. the GS-518 servo is a piece of crap. Gaui sell servo without grease in the gear box!? You can see hardly any lubricant in it! And yes it’s a brand new servo in from the bag in the combo! The more I’m into building it the more frustration I have. This heli is just too amazing and fun to work with.
How I started taking the servo apart is I had this dry and rough spot while turning the arm and damn, that explain why this is happening! Now I have to take the cyclical off the mount and open and check them all and make sure they are greased properly! Lack of lubricant is just destined for pre-mature failure!

[rcwng]

Helicrow,
Yeah I have the same problem. It's the only two reaming problem I have with this heli and I think it's hindering the throttle travel too if I put the canopy on. I used a 1450mAh Life and it's barely fit and I put little silicone glue between FG and rubber on the canopy holes hopefully to prevent the edges from cutting the rubbers.
My new problem please see below. Do you have this problem?
https://www.helifreak.com/showthread...=8#post7685811