RunRyder RC
WATCH
 1 page 713 views POST REPLY
HomeAircraftHelicopter
e-
Align
T-REX 450 › Need gy401 setup travel help
10-16-2010 05:13 AM  8 years agoPost 1
mustang67ford

rrKey Veteran

Central Pennsylvania

My Posts: All  Forum  Topic

I am completing my build of a trex450'pro and just installded the gyro. I am using a futaba 7c radio and gy401. I have done all by watching the helifreak videos. The problem I am having is the travel distance. I have the pushrod ball mounted 10mm and the gyro limit all the way down. I still have too much throw. I can move the ball 1 more hole in, but I doubt it will fix the problem. What else can I do as I know I can't use endpoint adjustment. Thanks

PM  EMAIL  GALLERY  Attn:RR  Quote
10-16-2010 06:03 AM  8 years agoPost 2
dkshema

rrMaster

Cedar Rapids, IA

My Posts: All  Forum  Topic

Set the TRAVEL LIMIT on the 401 to 100%.

Set your rudder endpoints to 100%.

Initialize the gyro in HH mode (required always), then switch over to rate/normal mode. The servo will follow the stick and return to center when you go to normal mode.

Rudder set to NEUTRAL, sub-trim set to zero. Rudder trim set to zero.

Figure out which position of the servo arm will get you a hole so that a line through its center and the center of the output shaft is perpendicular to the tail boom. You may have to try the servo arm on in more than one position (the splines of the shaft make it so the arm will fit with the proper orientation in only one position. If you end up needing a bit of subtrim to get the output arm in the right position, use it.

With things set at neutral, set the length of the TR pushrod such that the TR pitch slider is centered in its travel range on the TR shaft.

Now, figure out the distance to mount the ball link from the center of the servo such that at full deflection, the servo arm moves at least +/- 45 degrees from neutral, without causing the pitch slider to run into a mechanical stop at either end of travel.

If you have the distance from center too long, the servo will only have to move a little bit to run the slider to its stops. AS you move the ball link inward, toward center, the servo arm will travel further and further before bottoming the slider out at either end of travel. When you find the distance out from center where you get +/- 45 degrees of servo travel, and the pitch slider doesn't come up against a hard stop at either end, that is the place to mount the ball on the servo arm.

Once you get there, again start up in HH mode, then switch to normal mode. Hover the heli. If the nose yaws left or right, adjust the linkage (shorter/longer) until the heli will hover without wanting to yaw left or right. Land, fine-tune the TRAVEL LIMIT setting on the gyro to eliminate any binding at either end of travel.

The goal here is to have the servo arm perpendicular to the tail boom at neutral, to have the TRAVEL LIMIT adjustment on the gyro as close to 100% as possible, and to have at least +/- 45 degrees of servo travel from center before the TR pitch slider bottoms out at either end of travel.

On a 450, you'll probably end up somewhere in the vicinity of 5-7 mm out from center on the servo.

Switch back to HH mode, go fly.

-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz

PM  EMAIL  GALLERY  Attn:RR  Quote
10-16-2010 12:27 PM  8 years agoPost 3
ch-47c

rrElite Veteran

san jose, ca

My Posts: All  Forum  Topic

Well explained dkshema. Although I'm not using a GY401, I used a Quark and I have my servo arm ball at 7.5mm from center on my 450Pro. I also flipped by T/R blade grips.

PM  EMAIL  GALLERY  Attn:RR  Quote
10-16-2010 04:50 PM  8 years agoPost 4
mustang67ford

rrKey Veteran

Central Pennsylvania

My Posts: All  Forum  Topic

Thanks, I'll see what I can do
With it.

PM  EMAIL  GALLERY  Attn:RR  Quote
10-16-2010 08:34 PM  8 years agoPost 5
mustang67ford

rrKey Veteran

Central Pennsylvania

My Posts: All  Forum  Topic

Moves to the innermost hole. Just barely made it, but no binding so all good. Still have to fly it though.

PM  EMAIL  GALLERY  Attn:RR  Quote
WATCH
 1 page 713 views POST REPLY
HomeAircraftHelicopter
e-
Align
T-REX 450 › Need gy401 setup travel help
 Print TOPIC  Make Suggestion 

 3  Topic Subscribe

Saturday, December 15 - 9:48 pm - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

The RC discussion world needs to consolidate. RR is now one choice for that. Its software is cutting edge. It hosts on-topic advertising. Help RR increase traffic buy making suggestions, posting in RR's new areas (sites) and by spreading the word.

The RunRyder Difference

• Category system to allow Rep/Vendor postings.
• Classifieds with sold (hidden) category.
• Classifieds with separate view new.
• Answer PMs offsite via email reply.
• Member gallery photos with advanced scripting.
• Gallery photo viewer integrated into postings.
• Highly refined search with advanced back end.
• Hosts its own high end fast response servers.
• Hosts thousands of HD event coverage videos.
• Rewrote entire code base with latest technology.
• No off-topic (annoying) click bait advertising.
Login Here
 New Subscriptions 
 Buddies Online