Official GAUI NX4 Build Thread

[mode1mike]

My head bolts were very tight but I was very lucky to have 2 new allen wrenches 1 screw broke loose, when I examined the one that came out there was no thread lock.
It was so tight that when it came apart the wrench was bending.
I did try to remove the other screw and gave up, put the red dampers in and blue thread lock good to go!!

[dksia]

A few other issues with my kit.

The supplied 2.6 mm bolts for servo mounting are a problem when trying to mount the aileron and pitch servos. My kit included 2.6 x 12 mm bolts. The manual calls out 2.6 x 10. As the holes in the angled servo mounts are not drilled/tapped all the way through, the 12 mm bolts are too long and required a visit from Dr. Dremel.

The four holes (two each) in the motor mounts -- for bolting the mounts to the CF frames were drilled all the way through, but the tap itself was not run all the way through, preventing the four 3 x 8 mm screws from being tightened down to secure the motor mounts. For this, I had a 3 mm tap on hand, and quickly solved that problem.

The kit overall is really nice and well thought out, but there are a few places where Gaui needs to address the ability to build without needing to make minor mods here and there.

Also -- when setting the machine up, what is the recommended overall collective pitch range and initial cyclic pitch travel?

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Edit -- I downloaded the current manual from Gaui. In this version, it appears that the servos should be mounted using their rubber grommets, as opposed to the manual I have, which shows the grommets are not used. That makes more sense, as this is a nitro heli with its attendant motor vibes. I'll add those and see if the 12 mm bolts are still on the long side.

[dksia]

I added the rubber servo grommets and used the brass eyelets that come with the Align servos, the bolts are much happier, although 10 mm would still be preferred over 12 mm length.

No biggie.

[automagp68]

Awesome post!

I am so pumped to see this!

I have gotten away from electric and im having a blast with my trexx700 nitro which is my first nitro bird

With that being said i only got a align because Gaui was not offering a nitro

I AM SO PUMPED that gaui is going in the nitro direction even if its not in the big bird sizes

This thing looks like an x5 on nitro PLEASE PLEASE PLEASE gaui make an NX7

I would buy that in a heart beat regardless of the cost! All of this is great news!
Nice thread and beautiful heli

[Matt Nasca]

Originally Posted by automagp68

Awesome post!

I am so pumped to see this!

I have gotten away from electric and im having a blast with my trexx700 nitro which is my first nitro bird

With that being said i only got a align because Gaui was not offering a nitro

I AM SO PUMPED that gaui is going in the nitro direction even if its not in the big bird sizes

This thing looks like an x5 on nitro PLEASE PLEASE PLEASE gaui make an NX7

I would buy that in a heart beat regardless of the cost! All of this is great news!
Nice thread and beautiful heli

Thanks! Directly from GAUI, "The NX will be a series" Woot!

[Matt Nasca]

One NX4 at 3000 headspeed coming up!

The clutch bell, pinion and frame stiffener upgrade was super easy to install. It'll probably be a few weeks to a month before I can test it. Today's high was -7 F.

[caralmar]

Originally Posted by Matt Nasca

One NX4 at 3000 headspeed coming up!

The clutch bell, pinion and frame stiffener upgrade was super easy to install. It'll probably be a few weeks to a month before I can test it. Today's high was -7 F.

Attachment 386552

Looks sweet!

Matt, I'm having a weird issue and I'm not sure where to start on it. Every once in a while, my engine stutters, especially after a hard stop. For example, if I fly to my right and turn and then do a full speed pass in front of me, sometimes I flick elevator up really hard and stop the heli inverted. The maneuver is easy, but it looks so cool, especially if you do it at high speed.

Well, right when I stop the heli, the engine stutters. Its almost as if its trying to catch up. I have a feeling this is a problem with the vbar governor, but I don't know. The other thing I thought of was perhaps a lack of pressure and the engine starving for fuel?

Do you run the vbar nitro governor? If so, did you have to make any adjustments to the nitro-specific parameters? Thanks!

[Matt Nasca]

Originally Posted by caralmar

Looks sweet!

Matt, I'm having a weird issue and I'm not sure where to start on it. Every once in a while, my engine stutters, especially after a hard stop. For example, if I fly to my right and turn and then do a full speed pass in front of me, sometimes I flick elevator up really hard and stop the heli inverted. The maneuver is easy, but it looks so cool, especially if you do it at high speed.

Well, right when I stop the heli, the engine stutters. Its almost as if its trying to catch up. I have a feeling this is a problem with the vbar governor, but I don't know. The other thing I thought of was perhaps a lack of pressure and the engine starving for fuel?

Do you run the vbar nitro governor? If so, did you have to make any adjustments to the nitro-specific parameters? Thanks!

I do believe that is a VBar governor specific issue as I've seen that in my .90 nitro and others as well. I run the GAUI governor on the NX4 and don't experience what you are describing.

Can you post what your governor numbers are (both main slider and doctor's hat) and I will compare them to my 90's? I have just about fixed it on that model.

[caralmar]

Originally Posted by Matt Nasca

I do believe that is a VBar governor specific issue as I've seen that in my .90 nitro and others as well. I run the GAUI governor on the NX4 and don't experience what you are describing.

Can you post what your governor numbers are (both main slider and doctor's hat) and I will compare them to my 90's? I have just about fixed it on that model.

Hmmm... ok, I haven't experienced this in my 90s, also with vbar gov.

Ok, on the NX4, I left the main slider at the default of 60.

Dr. hat... changed runup to 3 and min. governor to -50%. All other values are default for nitro.

Thanks Matt!

Carlos.

[Matt Nasca]

Originally Posted by caralmar

Hmmm... ok, I haven't experienced this in my 90s, also with vbar gov.

Ok, on the NX4, I left the main slider at the default of 60.

Dr. hat... changed runup to 3 and min. governor to -50%. All other values are default for nitro.

Thanks Matt!

Carlos.

Ok I'll check when I get home from work and post back. Off the bat try -10 for min governor. As soon as you unload the heli suddenly, the motor comes really close to idle with -50. (-100 and + 100 means 0 is 50% and -50 is actually 25%) That could cause it to load and then studder trying to burn off the fuel.

[caralmar]

Originally Posted by Matt Nasca

Ok I'll check when I get home from work and post back. Off the bat try -10 for min governor. As soon as you unload the heli suddenly the motor comes really close to idle with -50. (-110 and plus 100 means 0 is 50% and -50 is actually 25%) That could cause it to load and then studder trying to burn off the fuel.

Ok, I'll give it a shot. Are you happy with the Gaui governor? I may give it a try.

[Matt Nasca]

Originally Posted by caralmar

Ok, I'll give it a shot. Are you happy with the Gaui governor? I may give it a try.

Ya I'm pleased with it, it's worked well so far. Another thing is on a separate flight, reduce your governor gain to about 45-50. A nitro motor throttle works much slower than an electric and you may also be noticing the lag where the VBar governor is just working the throttle faster that the engine can keep up.

[caralmar]

Originally Posted by Matt Nasca

Ya I'm pleased with it, it's worked well so far.

Yeah, to be honest, I'm not thrilled with the vbar nitro governor. It worked fantastic with the electric helis, but for nitro, I just have had too many hiccups along the way with all my nitro helis. Could be just inexperience on my end.

But for example, the bailout works great, and in some of my helis, it works on the bench, while in my new 700N it does not. The bailout never arms while on the bench. I opened a ticket with RH about it and MrMel told me that it should never arm on the bench. However, I have two other nitros and I can do the bailout thing on both of them while on the bench. This helps you dial in the lowest number on the TH curve that will still give you bailout without triggering soft start. Very useful!

Other times, I hear the nitro screaming while the head is unloaded and then stutter when I do I hard stop. It also gets "confused" sometimes during constant piro flips. I'm adding just enough collective to keep it in the air yet I hear the engine revving or slowing as I'm stirring the cyclic.

Perhaps I just need to play with it a bit more.

[Matt Nasca]

Originally Posted by caralmar

Yeah, to be honest, I'm not thrilled with the vbar nitro governor. It worked fantastic with the electric helis, but for nitro, I just have had too many hiccups along the way with all my nitro helis. Could be just inexperience on my end.

But for example, the bailout works great, and in some of my helis, it works on the bench, while in my new 700N it does not. The bailout never arms while on the bench. I opened a ticket with RH about it and MrMel told me that it should never arm on the bench. However, I have two other nitros and I can do the bailout thing on both of them while on the bench. This helps you dial in the lowest number on the TH curve that will still give you bailout without triggering soft start. Very useful!

Other times, I hear the nitro screaming while the head is unloaded and then stutter when I do I hard stop. It also gets "confused" sometimes during constant piro flips. I'm adding just enough collective to keep it in the air yet I hear the engine revving or slowing as I'm stirring the cyclic.

Perhaps I just need to play with it a bit more.

An easy way to use the a bailout on a nitro is to actually NOT use the built-in bailout. Just use the ramp, in the governor menu, and set it to 25 or 30 or maybe 35 and it'll bail out just fine! My governor is OFF in normal so I can spool up. The governor is only active in ST1 and ST2.

I agree with you that it is amazing on electrics. The VBar governor does work well on nitros after you get it tuned. I had help from some really cool guys in Texas, Rusty, Rob and John, and they really helped me to understand how the VBar governor works with the nitros. After that help and some self learning about it, mine works great.

Stick with it man, try some things and you'll figure it out. I'll post my settings in a few hours when I get home.

[Matt Nasca]

OK, my VBar governor Nitro settings are:

45 Main slider
30 Runup
25 Differential
25 Integral
30 Max P Limiter
40 Cyclic Add
50 Collective Dynamic
0 Collective Reduce
-10% Min Governor

[caralmar]

Originally Posted by Matt Nasca

OK, my VBar governor Nitro settings are:

45 Main slider
30 Runup
25 Differential
25 Integral
30 Max P Limiter
40 Cyclic Add
50 Collective Dynamic
0 Collective Reduce
-10% Min Governor

Cool! I'll load these up on a separate bank and try and see if I can tell any difference. THANKS!

BTW, I did 3 quick flights today with -10% on the min governor and also opened up the carb a couple clicks past 1 turn. I was still able to make it stutter once or twice, but not as bad as it was doing it before. It was very windy so it was hard to tell sometimes if it was stuttering or if it was just windy!

I'll try again Sat. and this time I'll program in your settings into another bank.

Gracias again!

Carlos.

[caralmar]

Originally Posted by caralmar

Cool! I'll load these up on a separate bank and try and see if I can tell any difference. THANKS!

BTW, I did 3 quick flights today with -10% on the min governor and also opened up the carb a couple clicks past 1 turn. I was still able to make it stutter once or twice, but not as bad as it was doing it before. It was very windy so it was hard to tell sometimes if it was stuttering or if it was just windy!

I'll try again Sat. and this time I'll program in your settings into another bank.

Gracias again!

Carlos.

LOL... I took everything to the field this morning except for my computer! DUH!!! So I couldn't try your settings. Matt, are you using combined mode or 2 channel mode?

I'm using combined mode, and by looking at your numbers, if I bump up the runup that high, my spoolup will be crazy fast... instead of the nice soft start I have right now. I flew it today after playing around a click or two at a time on the needle and got it to make really good power and eliminated the stutter, so I think I'm going to stick with these settings for now, but I thank you very much anyway!

Carlos.

[hepat911]

Hey , Thanks for all info , mine arived today , verry easy to build , and fast ,,,only when you arive on the feul tank section ,,,,, i have no fingers anymore afther putting all rubbers on place ,, now the compleet rubber is laying in the tank ,,i see tomorow how i can take this out the tank again ,, .
Greats and thanks

[vteknical]

You're pretty much screwed if the rubber and nipple are inside the tank. I had this happen on another model and I wound up buying another tank after some frustration.

[Matt Nasca]

New carbon fiber skids for the X5 and NX4