250 Picked up a trex 250 today
- Thread starter xokia
- Start date
Tony
Staff member
I would mount the ESC in a different location as well. If that is one of the later versions, and judging by the DFC head it is, you should be able to mount it under the battery tray. Much cleaner look. And if you are running the DX8, and there is a 3GX in the frame, you can get rid of that Rx too.
Your making me want the 250 again, you need to stop lmao. I love those little heli's even though they are a pain sometimes.
Your making me want the 250 again, you need to stop lmao. I love those little heli's even though they are a pain sometimes.
I bought it this way. I removed the RX already but like the ESC where its at. The thing gets pretty warm and where its at it will get a breeze from the blades. Right now I have a serious tail oscillation that I haven't figured out yet.
murankar
Staff member
The tail can be any number of loose things. I would start by checking every screw in the tail. Make sure of no binding of any kind. Bearings should spin freely. Next check the gyro gains. I am not sure how a dx8 works on gains but on the dx6 or th9x the closer to 50% the less gain you will have along with less wag in the tail. The further away from 50% the more gain you will have.
I hope this helps.
I hope this helps.
helicc16
the Smoothie Pilot
If you using just Sat Rx, make sure to set output channel in the gyro menu to aux 2 ( NOT gear). Check the programming in ESC, making sure it is programed to start in SOFT START mode ( and NOT the SOFT START + GOVERNOR mode). For DX8, a gyro gain value of +40 is a good place to start.
You might be onto something program which output channel to aux2? I will try this at lunch time.
*edit* I ran out to my car and tried it out LOL.
You nailed it!!! I had it set to gear. A big thank you.
I didnt test fly it just held it in my hand and throttled it up. Previously the tail would shake violently.
Now its smooth like it should be. I'll test fly this little bugger after I get home from work.
I picked this helicopter up and a DX7 for $380 already sold the DX7 for $150 and I'll sell the 7 channel RX on ebay. I thought it was a pretty decent deal it was brand new never flown.
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I have a quick question since I've never had to do this on another helicopter. This one the servos have to much travel and you can bind them pretty easily and then that shuts the ESC down and everything reboots. There is a step where you set the max collective and max cyclic. Are you supposed to do this before or after DIR setup?
I also upgrade to firmware 3.0 so setup aileron and elevator gain to 105.
So the steps I did was to DIR setup with full movement
Upgrade firmware then set gains to 105
then set the max pitch to about 13 degrees and max cyclic to about 8 degrees
Then I repeated the DIR setup
Now my elevator and aileron gain are about 43 I dont know if that is right or if I should set the gain AFTER I do DIR setup.
I also upgrade to firmware 3.0 so setup aileron and elevator gain to 105.
So the steps I did was to DIR setup with full movement
Upgrade firmware then set gains to 105
then set the max pitch to about 13 degrees and max cyclic to about 8 degrees
Then I repeated the DIR setup
Now my elevator and aileron gain are about 43 I dont know if that is right or if I should set the gain AFTER I do DIR setup.
Tony
Staff member
The gain on the pots shouldn't change. Are you talking about the ail/ele gyro gains? Or are you talking about endpoints? Because gains and the binding have nothing to do with each other. The gains for the ail/ele are set in the computer program (so you can see the output) but are physically adjusted on top of the gyro with the two pots.
If you are having binding issues, then you need to go into your swash menu and lower those numbers until you get the amount of pitch you want. about 8º on cyclic, and I would not go over 11º on collective. Hope this makes sense.
If you are having binding issues, then you need to go into your swash menu and lower those numbers until you get the amount of pitch you want. about 8º on cyclic, and I would not go over 11º on collective. Hope this makes sense.
There were two questions, that probably wasn't clear. I know that the gains have nothing to do with binding. They start out at 105 after doing DIR setup and setting the endpoints the value drops down to 43 without touching the pots.
I'm still not clear on how I set the cyclic pitch I go into swashplate on my DX8 and adjust the elevator percentage while measuring the pitch of the blades with the cyclic stick pushed forward and the blades perpendicular to the helicopter body and collective at mid stick.
1. when am I supposed to set the cyclic pitch?
a. while in DIR setup?
b. after exiting DIR setup
2. If I set the cyclic pitch to 8 degrees while in DIR setup I can get the servos to bind after I exit DIR setup.
If I measure cyclic pitch after setting to 8 degree while in DIR setup when I exit DIR setup I measure 14 degrees
Yea I think I had it right the first time I went through it, the helicopter just felt a little jelloish. So I went through the setup again and since then its acting wierd. I think I am going to reflash it and start from the beginning.
8 degrees cyclic seems pretty low is there a reason for that other than the binding issue? If I can get more without binding is there any reason I shouldnt do it? I'm starting to understand the frustration people have with the 3GX unit LOL.
This is also the first helicopter I have run with just a satellite reciever. It will only bind into DSM2 and 22ms. I don't really care for this little helicopter but I dont think I'll run just satellites anymore with the 3GX.
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Tony
Staff member
You must set 8º of cyclic so that the gyro knows how much pitch is going into the blades. This is where you get your roll and pitch rates from in the program on the computer. V2.1 and up need to have this done, it's a requirement.
Don't let what others are saying persuade you into thinking the 3GX is crap. It's a great gyro, but it's also touchy. You have to treat it like you would a woman, with finesse.
And if it's a full align heli, and you don't want it, make me a deal I can't refuse. I want one of these, just don't want to pay the premium for it lmao.
Don't let what others are saying persuade you into thinking the 3GX is crap. It's a great gyro, but it's also touchy. You have to treat it like you would a woman, with finesse.
And if it's a full align heli, and you don't want it, make me a deal I can't refuse. I want one of these, just don't want to pay the premium for it lmao.
Yea it's all align. The guy put it together then crashed his 600 so needed the money. It was never flown until I got it its a brand new 250 pro dfc. I like the little thing I intend to keep it. I ran into a new problem today the damn thing lost power in the air and just fell out of the sky. I believe the problem is the BEC inside the ESC. I bought an external BEC that I have yet to get installed.
Something is not quite right with the 3GX I lost control and took a nose dive into the dirt. Broke feathering shaft and bent main shaft. So it's gonna be a while I need to sort out the 3GX issues.
Yea that's what happened to this one. I had control an then it's as if it was trying to correct and giving it to much aileron. It was hard as heck to fly. I got it as close to the ground as I could then hit throttle hold. I have a 3GX in my 450 and that one flies just fine so I'm not sure what I did wrong yet.