SlezY's NX4 with GoEngine GH56

[SlezY83]

Here is my new heli – GAUI NX4 Gasser.

I bought NX4 second hand from UK via ebay in very horrible status, but I have resurrected it :-).
It was glow version and because I have Go Engine GH 56 at home with muffler (Go Engine GH56 was intended for my T-Rex 600, but decided to use Zenoah conversion for T-Rex 600).

Heli configuration:
Cyclic: DS515
Throttle: DS510
Tail: DS650 (installed on the tail because of weight balance). Full size of the servo because I red some mini servos were failure.
FBL: Spirit (with rescue and governor)
Governor: For now, Align. Then, I am going to try the one in Spirit.
Engine: Go Engine GH 56
Muffler: CiCa Heli Power
Receiver and servos battery: 1450mAh LiFe
Ignition battery: 700 mAh LiFe
Spektrum Telemetry and 8CH receiver (it is used 7CH now)
Weight is little high: 2489g without canopy and fuel.
Blades: After break in, Halo Blades 450mm and 76mm RotorTech. For first fly, highly used Align 425 and GAUI plastic will be used.

I modified bottom plate little bit. Better to say is that I create a new one – by hand file/rasp and saw – two evenings task :-).

I modified the GH 56 little to fit in NX4 case. I bought engine holder and clutch adapter for T-10 engine and everything fits.

The engine was repaired because I broke it in T-Rex 600 (my first gasser). The engine was repaired (piston, piston ring, piston sleeve and piston pin for sure) and therefore it had to be broken in.

Motor has about 1l of gas through on idle speed without blades. I do not use pressurizing from muffler now.
Needles settings were:
Mixture: 3 turns out from fully closed (or 1 turn out from closed of throttle)
H: 2 turns out.
Seems it was very rich, because it was lot of unburned oil in the muffler. Temperature of engine was about 90C and muffler about 115C (environment temp was maybe more than 30C!)

I have one important question – for my inspiration, what is yours needle settings?
I read user manual for GAUI T-10, and there is mixture 4 1/4 out and H 1 3/4 out for break in and H 1 1/4 after break in.
But 4 1/4 on mixture needle, it seems too much…

Roman

[cruzroy]

thats a purdy bird you got there........i like the fancy muffler......tell us ho it works out

mine needles are LNS 3/4 out, and running smooth low idle

to HNS is at 3 out from closed.....and thats real rick......but bunning like that for another tank

i tried the 41/2 out on LNS...she would not run unless my throttle was at midpoint......i dodnt think its rigt

these motors truth are still and a trail and error phase......sorry but true

and i notice you have a guai head on a go engine....keep it cool.....little less material to my go.....watch the tem

im keeping mine at 180.....but havent got in air yet....getting close tho

[pugdavey]

So the t-10 clutch mount fits with a 50 motor ?

[SlezY83]

Originally Posted by pugdavey

So the t-10 clutch mount fits with a 50 motor ?

Not sure, whether you needs clutch mount if you want to fit 50 size motor. I think, that you only need T-10 engine mount to fit a 50 engine.
The special clutch mount is there because of additional ring for ignition magnet/sensor.

Better to look in some topics, because I saw NX4 with 50 size engine on Youtube...

Roman

[SlezY83]

Today, I idled next tank and then tried to go in hover. Unfortunately, the heli went to a side and I hit ground with tail blades.

Video is here:

GAUI NX4 Gasser - unsuccessful first hover - SOLVED (1 min 28 sec)

(in the midle, i set end point of my throttle curve from 80% to 40%).

Then, I removed blades (tail blades were already removed :-)), connected Spirit FBL to a computer and measured vibrations.
I measured head rotation by optical tachometer. It was about 1450 RPM +- 100.
From the vibration chart, it discovered vibration peak at 10000RPM (when I place cursor on the peak, it show me corresponded RPM).

I checked the engine part in detail and a screw from muffler was loose - it could cause the vibrations. Unfortunately, the thread in the muffler adapter is gone - I try to repair it or I will install Align 50 muffler, which I have at home as well.
I am going to remove the metal plate from the FBL pad - recommendation from producer and will try it again...

Charts from Spirit FBL are attached as well.

But at the end, I discovered unpleasant think - interference from ignition. I saw it on my T-Rex 600 when I used Go engine 56 and now, it is back. I have to check the spark plug sleeve:

Go Engine GH56 - interference from ignition - again - SOLVED (0 min 16 sec)

[bgymr]

I just went through this. The reason it happened to me is that where I had the plug cap going over the plug itself, then it came out straight like yours does. Then that bend in the "wire net". Well, where that wire netting over your ignition wire meets the plug cap it easily freys. Make sure your solder joint there is good. I hope I'm making some sense.

[SlezY83]

Hello bgymr,
Thank you for your tips! I think that I know what you mean. To remove the black isolation from spark plug cap and check the wires (do you mean the shielded wire?). I will do so.
I read your story and it seems to be very similar. Anyway, how about the 90deg spark plug cap? Is it a win?

I saw, that you are running without muffler pressure – the same on my side. For my information, what is your needle setting (mixture and H)?
I am now on 3 turns out on mixture (from fully closed the screw /throttle have to be moved to about 1/2 to reach this/ position or 1 turn out from closed throttle servo) and 2 turns out on H. But I was only in idle, not in hover yet.

Roman

[bgymr]

Yes, the 90 degree is the way to go. You will have to move the the tail servo out, but it's no big deal. During maintenance I will have to pull the tail servo to get the motor out, but I don't think that is a big deal. I'm trying to workout a system where I use the stand for the aux tank to place the ignition unit on it. So far I haven't been successful. My unit is on the bottom of the heli.

Yes, the shielded wire. I put duck tape over mine. As silly as it seems, duck tape is good at taking away vibrations.

I'll check my needles tonight. I wouldn't go by other peoples needle setting. Just set it rich, and fly it. This thing has gobs of power.

The little plastic tubing you have on your muffler will more than likely melt off once you start flying. I took the nipple off my muffler, and put a screw in.

The other thing I had a lot of trouble with is to keep the muffler on. What worked for me is to put RTV silicone on instead of the aluminum gasket. It would heat up and get skinnier between the motor and muffler which would loosen the bolts. Also, I would bring my driver and pliers to the field and once the motor/muffler heated up, I would tighten them down really hard. I put a nut on the other side of the muffler, because the muffler stripped.

[SlezY83]

Originally Posted by bgymr

Yes, the 90 degree is the way to go. You will have to move the the tail servo out, but it's no big deal. During maintenance I will have to pull the tail servo to get the motor out, but I don't think that is a big deal. I'm trying to workout a system where I use the stand for the aux tank to place the ignition unit on it. So far I haven't been successful. My unit is on the bottom of the heli.

I saw your solution – it looks nice. I already moved the servo on the tail because of weight balance and because I had full size tail servo at home.
I wanted to focus the HV in one place and therefore I used the front part. If necessary (I will see how about canopy mounting – it is next question mark :-)).
BTW, I removed the cover from my spark plug sleeve and it looks follows (I straighten some of the wires ):



I would say that it was source of the interference. But we will see today afternoon. I soldered it around together. Anyway, I am not proud to my soldering, because I was not able to attach the tin on the sleeve even I used tons of rosin and two transformer solder machines)

Originally Posted by bgymr

Yes, the shielded wire. I put duck tape over mine. As silly as it seems, duck tape is good at taking away vibrations.

Yes, I used duct tape on whole length of the HV wire.

Originally Posted by bgymr

I'll check my needles tonight. I wouldn't go by other peoples needle setting. Just set it rich, and fly it. This thing has gobs of power.

Did you find any?

Originally Posted by bgymr

The little plastic tubing you have on your muffler will more than likely melt off once you start flying. I took the nipple off my muffler, and put a screw in.

It was only for first testing and break in process – it will be removed and replaced by screw.

Originally Posted by bgymr

The other thing I had a lot of trouble with is to keep the muffler on. What worked for me is to put RTV silicone on instead of the aluminum gasket. It would heat up and get skinnier between the motor and muffler which would loosen the bolts. Also, I would bring my driver and pliers to the field and once the motor/muffler heated up, I would tighten them down really hard. I put a nut on the other side of the muffler, because the muffler stripped.

I wanted to use it as you sad (I used it for any engine), but I had a problem to buy M3x50 screws and I for inserting of nuts, I have to modify the muffler little. . When I bought M3x50 screws, they have only 20mm thread form the end – I have to extend it as well, but I am on a good way now.
Regarding the gasket, I use OILIT from Graupner. The original aluminium is only a pattern for cutting.

[bgymr]

Hey bud, I am 3 turns out on the low speed. I should be less, it almost stalls as it idles. But I don't mind. I like to run my engine for 20-30 seconds idling before I shut it down to let it cool from teh flight, and putting a lot of fuel in the motor helps it cool and stay well lubed.

On the HS I am 3.33 out. I had it leaner and it ran strong but I didn't need all the power. I just started my second gallon so I am taking it easy on the little guy. It has gobbs of power. It runs a little rough and I can lean that out, but i will do that as the motor breaks in.

The governor was key for me to get my motor to run right. I'm sure my throttle servo gets a workout with this heli.

Before I solder onto items like the spark plug boot, i take my dremmel to it and lightly run it across it to put little grooves and marks in it. The solder then sticks to that pretty easily. I don't have the duck tape running the whole lenght, but I think that is a wonderful idea. As funny as it sounds. If I were you I would avoid sharp turns with teh ignition wire. If you are going to keep yours where it is, I would cut it really short so it basically goes right into the unit. That would be ideal. I can't put mine there because I have a full size vbar so where your battery is my vbar is there, then where your ignition is my batteries are. Dominoes. I like your installation a lot. What did you use to put the servo on the boom?

Hope you love yours as much as I do mine.

[distructor]

SlezY I really like your modified lower plate. I'm sure it makes a difference in cooling. I was contemplating something similar, but I'm just going to copy your idea

[SlezY83]

I really do not know WHY it happened... I am really sad :-( - too much time and energy spent on modification of details. And money... Halo Blades 450 are still waiting.

Conditions
Oil:gas mix: about 15% (NOT 15:1)!
Engine had about 1,5l through on idle and then low rotation without blades (finally, about 7 tanks)
Mixture needle: 3 1/8
High needle: 2 1/2
It happened during first hover.
RPM at rotor about 1800.
Last information from telemetry about temperature was about 130C (266F)
Environment temp about 30C (86F)
Piston has no scratches.
Before it happened, the engine was 4 stroking...

[SlezY83]

@bgymr:
Regarding tail servo - I used tail servo holder for T-Rex 600 and connection for T-Rex 500.
T-Rex 600 tail servo holder is designed for 22,5mm tail boom.
NX4 has 22mm tail boom.
I placed a small piece of double side tape for compensation of the 0,5mm and definitely fixing the position.

Tail connection rod was bought vie e-bay in GoGo.RC shop.
And tail servo holder is available on e-bay as well and I think that hobbyking have it as well (but I bought the plastic one because of weight).

@distructor
Welcome ;-). I used "cuprextit" (I do not know whether is has the same meaning in EN). It is a plate for PCB, which is fully covered by copper from one side (it is possible to buy it in each shop with electronic parts). I only removed the copper from the one side (by FeCl3).
Unfortunately, I did not have time to check the temperature difference.

As I mentioned - too much time spent with details and completion...

Roman

[distructor]

Sorry to read about your engine :-(
What type of oil were you using when the engine broke?

[SlezY83]

I used Liqui Moly RACING Scooter 2T SYNTH.
I used it, when the engine was in T-Rex 600 and worked well before.

As I sad, I do not know what happened...

The question is, what next:
- Buy new engine (I do not have trust to the old one)
- Install glow engine OsMax 37.
- Sell everything connected with NX4

I have to think about it...

[SlezY83]

I wonder, whether Evolution 10GX would fit in NX4 case...

Advantages:
Connecting rod has a full bearing on one side - oil mix 20:1 (5%)
Include carburetor with fuel pump
Power peak in 16400 RPM.
Max RPM 18000
Should have same mounting as 50 size engines (I did not find full drawing)



Disadvantages:
Spark plug is not placed in cylinder straight
Carburetor will be littler bigger compare to standard 50 one
Maybe, 50 size fan shroud would be necessary to install it

[distructor]

I saw the first picture of the cylinder and thought maybe an oil breakdown, but your temperature seems to low for that. I don't know much about the oil you are using, but a 2T synthetic seems like it should work.
I didn't notice the connecting rod bushing. Crank pin looks wreaked as well

That lower connecting rod bushing looks like a weakness with this engine. After breaking of a couple gallons, it seems like it will go forever, but I've seen several people post pictures of the same failure during early breaking

If I were in your situation I'd wait till Go Engines has the version 2 of this engine available. I don't know if they did anything with the connecting rod, but the cylinder casting has larger fins, and the head is massive.

In the mean time maybe you could pick up a used .37 engine. It's a shame to give up in this heli, it is such a blast to fly.

[SlezY83]

Regarding the new version of Go Engine, which should come soon. I wrote to Go Engine one month ago and asked them about differences v1 and v2. The answer is here:
Piston, piston ring, sleeve - all are compatible with v1. Carburetor as well
What is different in V2:
crank case
cooling head
crankshaft - there is added weight
connection rod - old one was 4 little holes in bottom, new has only one dot.

I have some possibilities, which I am considering...:
1) Wait for v2 version
2) Use glow 37, which I have at home (but I am not enjoying to fly on nitro :-) - I want gas - it is psychological :-))
3) use this offer:
http://www.flying-hobby.com/gaui-t10...c-p-13021.html
160 USD + 40 USD shipping for T-10 (even is on backorder).
4) To sell everything...

I do not like option 2 and 4, but it is an option. Option 1 will cost much money, but could be more durable. Option 3 (even on backorder) is quite cheap, but the problems could come again and in this case, it would be more expensive...

[distructor]

I ran my engine on a test stand with an airplane prop crazy-glued to the smooth driver for the first 1/2 gallon. I felt it was easier to learn the needle settings on a test stand then on a helicopter. I don't remember what my test stand temperature readings were, but I'm sure it was higher then what yours got to.

I've been asking the USA distributor for Go engines about the V2. He says that the V2's have been shipped. He will also be offering the V2 head, but with the other changes in the V2, I may just get a complete engine. Damn, this thing is getting expensive

[blue_smoker]

Question. Where is the temp sensor loacated? Imho the that's very high temp for hovering. From the pics it looks like not enough lubrication on the crank pin. Hence why it locked up.