View Full Version : mx400pro test flight gone bad???? Need set up help please
jayhawk25
07-31-2007, 06:46 PM
I have a mx400pr futaba 6exh 2.4, 401 gyro, hs56's and a futaba digital tail servo. I plugged it all up, gyro set to dig. tx set to throttle and pitch curves of 0-25-50-75-100 and swash set at 1-S. as I idle up the gyro holds the heading awsome but then at just below half collective the tail starts to wag/search for a heading violently. I have flown 400/450 size heli's before but they were already set up. I am clueless about set up. Anyone that can help I would love to hear your thoughts. All my EPA's are 100% and the revo is off. AVCS vs. Rate is 80/60 on my TX. What am I dooing wrong?
warpspeed
08-01-2007, 08:50 AM
Where is your gyro mounted? If you put it under the mainshaft as per the manual that's probably the issue. Otherwise try turning down the gain-80 sounds a little high.
jayhawk25_2000
08-02-2007, 12:47 PM
I did put it under the main shaft. I also have a boom mounted tail servo. should I put the gyro on top and relocate the tail servo back where it should be, under the boom between the frame? I thought as long as the gyro was longitudinal to the rotating axis it would not matter where it was mounted. Am I wrong on that idea? Thanks.
warpspeed
08-02-2007, 09:14 PM
Well technically no, you're not wrong. But for whatever reason the gyro just won't work there-darn shame since that spot seems tailor made for it.I went thru the same thing and wound up having to buy the mounting plate and putting it above the boom, which of course is not the ideal location. Anyway you can leave the servo where it's at, and once the gyro is moved you should be good to go!
tigerrd
08-03-2007, 05:24 AM
Place your 401 at the bottom of your frame at the rear on the double sided tape with the metal plate under that and another double sided tape below that. Raven darkcloud set mine up like that and works fine with no glitches. He even has his set up that way and has flown 3D with no problems.
jayhawk25_2000
08-03-2007, 10:18 AM
I will relocate it. It is going on the frame below where its mounted now. I will just have to relocate my receiver and re route all the wires. Any suggestions on initial setting for the tx and gyro?
tigerrd
08-04-2007, 02:17 PM
Check out Finless Bob's trex 450 setup video on the 401. http://video.helifreak.com/?subpath=finless/trex450&filename=gyro_setup.wmv
warpspeed
08-06-2007, 09:00 PM
Yeah, Bob's vid's are tops and probably the best place to start, then you can tune to your liking from there. Just keep in mind he sets up for 3d so his pitch and curves are probably a little on the aggressive side.
Tigerrd, can you post a pic of how you have yours mounted? Are you talking about under the frame between the struts?