450 Align t-rex 450 pro dfc build and 3gx setup

flysolo

Member
So, apparently I was in someone else's thread and fudding things up so from now I will post all questions in this thread.

I have completed the build minus a stripped screw head.. I'm using Hudy allen wrenches that are pretty new and they should be of good quality. I think the problem was the screw hole was not perfectly lined up when I tried to tighten it and stripped the head. Well, I got it out with a polygrip so now I need to replace it somehow. It's one of the longer back ones that secure the bottom plate and tail boom support rods.

When that is done I move on to 3gx setup. Before I start I want to make sure I run the right software. I have to download it and the first question is about the version. Do I need a specific version for my 3gx or is it best to download the latest one?

Also, do I reverse the servos and swash functions before i plug the 3gx into the computer?
 

stokke

Well-Known Member
If your device came with the 1.2 version, I'd stick with that one for now.
The 1.2 has an easier set-up than the 2.1 version.

In the 1.2, you only have to click "beginner" on a slider in one of the first pages. And that's that.
In 2.1 you have to set all settings individually.

I started out on the 1.2, flew it for a couple of weeks, then upgraded to the 2.1 and started tinkering with that.
 

flysolo

Member
Ok, sounds lite 1.2 is the way to go but I don't know wich version it came with, I can't run that small disc on my computer so I have to download the software.

To make this absolutely clear to me, is the version just the software running on the computer or is it the firmware version on the actaul 3gx unit?
 

flysolo

Member
Aha, there it is. Thank you!

I have V2.0 so i guess I have to start with that one then? Or can I still run the easier setup somehow?
 

stokke

Well-Known Member
Aha, there it is. Thank you!

I have V2.0 so i guess I have to start with that one then? Or can I still run the easier setup somehow?

In that case, you'd want this software: http://ms.align.com.tw/3g_update/ALIGN_3GX_V2.0.rar

I'm not sure if the "difficulty slider" has been removed in 2.0.
If it's not there, then I'd just flash to 2.1.

- - - Updated - - -

If you decide to flash to the 2.1 version, you can find my "beginner set-up" here: http://www.rc-help.com/showthread.php/4028-Marius-learning-to-fly-quot-video-diary-quot?p=23361&viewfull=1#post23361
 

flysolo

Member
Great, thanks!

Now away to the hardware store to find a replacement screw, then I'm gonna read up on the 3gx setup, your thread seems to contain a lot of useful info.

-Niklas
 

Tony

Staff member
His thread is FRIGGIN HUGE hahaha. There is a lot of great information in there that can help you out but don't be afraid to ask in here as well. There is no such thing as too much information. Hope to see you in the air soon.
 

flysolo

Member
I can't wait to get it up in the air!

When checked everything now i realize that the tail servo has a linkage ball that is a little bit longer than the others for tightening with a nut on the other side and that the ball link on it is so tight it's hard to move. I've verified that it is the linkage ball and not the ball link that makes it so tight. Is this by design or should it be moving as freely as all the other ones?
 

stokke

Well-Known Member
I don't understand the question properly I think...
Are you manually adjusting the pitch for the tail blades, and they're hard to move..?
 

flysolo

Member
No, the ball link on the rudder control rod that connects to the ball on the tail servo is super tight. All other ball links move freely - swash, servos and tail side of the control rod. Just this one is super tight.

I went and bought a small round file, gonna try to make the insdide of the ball link a litle bigger. I think really what I need is somethning like this

Turnigy 4mm Ball End Reamer
 

flysolo

Member
File didn't work nice, found another tip about using plyers and pressing the ball link againt the ball to make it move smoother. I think it worked, finally ready for 3gx setup.
 

stokke

Well-Known Member
Ah, OK.
Yes, the tool you'd need is a ball link sizer as you found.
The links are supposed to move freely, but not so free they'd fall under their own weight.

Good luck!
 

flysolo

Member
So I started the setup now. I had version 2.0 and the first thing I did was update to 2.1

Sorry if theese questions have been asked and answered many times, I've read so much about setup now that my head is spinning and I want to make sure with you guys that I got things right..

I think first I need to get servo horns(arms?) at 90, swash levelled and 0 pitch right at mid-stick? When I power up in dir mode and put left stick at mid-stick all the servo horns are a little bit low. It also shows when I use the pitch gauge that I have negative pitch at mid-stick.

How do I get the servo horns at 90 degrees? Is this adjusted with sub-trim on the Dx8 and I should do this in DIR-mode? Sub-trim for servo-horns, then adjust the lingages so that the swash is levelled and 0 pitch on the blades?
 

flysolo

Member
Great! You must think I'm pretty daft but I made so many stupid mistakes on this build I wanted to make sure.

Last one was when I started to play around a little with subtrim i realize I must have swapped pitch and ail servo connections somewhere along the way. Doh!

Just got it back together :)
 

Tony

Staff member
You seem to have a pretty good grasp of the concept. Everything mentioned above is correct. You will make sure your mid stick throttle curve is at 50% so you are exactly in the middle of the travel, you will use sub trim to level the servos then you will adjust the links to get 0º of pitch at mid stick. The real fun starts when you make sure you have the same positive and negative pitch or as close as you can get. +-.5 is okay.
 

flysolo

Member
Yeah, things are finally falling into place. After adding a little bit of subtrim I have 0 pitch at mid-stick, 8 Ail, 8 elev, 14 full negative and 14 full positive. This was without touching the linkages or altering swash functions!
 

Tony

Staff member
That is almost perfect. Just go into your swash mix and move the pitch down until you have about 11º of pitch. 14 is a lot and it will bob up and down since you won't have much control per degree of pitch. Other than that, everything looks perfect.
 

flysolo

Member
I think I'm done with the setup.. Is there a way to tell? The settings I'm not sure I got right is rudder endpoints and governor.

Also, both satellites are blinking, is this expected or should there be a solid light? Anyways, I spooled up on the floor and it seems very stable so I guess its time to take it outside. Any final tips before I go out and fly this thing into the ground?


To the people who helped me with this build, especially Tony and Marius: THANK YOU!
 
Top Bottom