Sarosh

I have Futaba T6EXHP transmitter and the GY401 came with a Futaba digital servo, not sure of the number, will have to look at it again.

the heli is new, so is everything electronically. I have not had a good luck with the darned gyro.

It wont hold head at all anymore. it did before, but not so well, but still could fly it and all. it would change to left 1-5 degree every few seconds when i had a successful flight with the heli. next day, it wont hold head at all, keeps spinning around. I have tried so many settings and setups. nothing works. the tail blade is constantly kicking as u can see from behind it. I have tried the setup on the raptortechnique.com. but the transmitter is different from mine as on there, and i dont have all those fancy settings. just some of them.

I have tried it with DS off, delay to 0 and full, limit has been on at full all time mostly.

Tried up switch at +100% even at +10% and -30%, tried dual rate, and EXP nothing really works.

The linkages are right on aligned, and moves freely as i think it is. im not sure how freely its supposed to move? by the blow of a air? Lol


One thing i noticed is that the tail rotor shaft has free play, if i wiggle the tail rotor grips, the shaft moves in and out, and u can see the belt pulley moving with it. Is it supposed to do that? i dont think it is supposed to do that. I checked the manual to see if i missed something and i didnt. the tail assembly is done right.

I am totally clueless. I have wasted a gallon of fuel running on the ground figuring out the gyro the whole time, trying several different settings.

Please help me out here!!!

Thanks

ncrego

My Feedback: (40)

I'll start at the end of your post. The play that you are describing on the tail shaft needs to be fixed. Good news is that it's easy and common. You put the end of the pulley on backwards, so it's not seating right and giving you that play. Open the tail box and compare the way the pulley looks to how it's shown in the manual, it'll be fairly obvious.

Here's how to set up that gyro. First, put the switch to DS mode. Then move the stick over all the way and adjust the limit setting so that there isn't any binding. Ideally you want it over 100%, if it's not, then move the ball on the servo horn in one spot, and try it again. I'm assuming you have the direction set properly, or you'd have much larger problems.

Go into your radio, and go make sure that the trim is centered on the rudder channel, including sub-trim. Go to the gyro screen, turn it on, and put the gyro switch on your TX up. Set the value on the screen to 70%, flip the switch down, and set it to -70.

Now go fly. Most likely, it'll all work fine, but it may take some fine tuning on the gyro screen. If the tail is wagging side to side quickly, turn the value down, if it isn't holding, turn the value up. Don't run it at 100%, it won't work. 99.9% of the helis I've set up with 401s (probably hundreds of them) will fly fine with the settings I gave you above, and won't need adjustments.

BarracudaHockey

My Feedback: (11)

The red pully is asssembled backwards.

Read the first of the two Titan reviews in the magazine section, it covers exactly the problem you are having. Specifically photos 29 and 30.

Sarosh

Thanks guys, i fixed the tail rotor, now it has no in and out play anymore.

Ncrego i tried your setup, it doesnt help at all. it still wants to spin around, if i make a slight adjustment, it will not respond or will go oppsoite way so fast. basically no control.

i have everything set up properly, the servo horn, rod, and linkage on the tail rotor. i followed the setup on raptortechnique.com

I am totally clueless now. My guess is the gyro is defective or broken or something..

When i do test with it before starting the motor, the gyro does respond when i turn the heli around. it responds just like it is supposed to in my guess as described on raptortechnique.

I wish i had a expert locally here, the nearest one is 2 hours away. and he is only at the store every other saturday, and this saturday he will be there. i just am not feeling like driving all the way down again. i have been in the cities the last 2 saturdays.

any other suggestions guys?

i set the servo horns in normal mode at 0% and when its centered the tail rotor horn is perfectly straight pointing to the boom as described on raptortechnique. when nose is turned left, the servo moves clockwise. so this is correct.

oh also the rudder servo i have on that came with the gy401 is Futaba S9254 digital servo.

I tried tonight with DS on and off, delay pot to 0 and full at different occasions. changed senstivity on HH mode on the TX from 70 to as high as 90 and then as low as 20 or 30

Oh boy this is a headache!!! maybe my rudder link rod isnt moving freely enough? i have 3 clips on, should i remove 2 and leave only 1 on?

tadawson

Flip the reverse switch on the gyro - having it backwards will cause the gyro to amplify instead of damp rotation. To double check, determine which direction the tail blades have to move to turn the nose to the right. Note the direction the servo arm needs to move to get that pitch . . . now turn the heli in HH mode, and rotate the nose to the LEFT. The servo MUST move to the direction seen for RIGHT rotation, or you have it backwards . . . . please note also that this has NOTHING to do with the reverse switch on the TX - that determines the direction of stick commands, and has nothing to do with servo movements generated by the gyro itself . . .

- Tim

ncrego

My Feedback: (40)

Like Tadawson said, the gyro is reversed. The second switch on the gyro next to DS is the direction, flip it the opposite from how it is. Double check the direction by moving the rudder stick on your transmitter to the right and watch the servo arm. It should move clockwise. If it doesn't, you need to reverse the rudder channel (channel 4) in your transmitter. Then, move the nose of the heli to the left, and watch the servo, it should move clockwise again (pulling the nose to the right if you were flying).

BarracudaHockey

My Feedback: (11)

First.
Verify the tail is rotating counter clockwise when the main rotor head spins clockwise. If the tail were to contact the ground it should throw dirt forwards towards the front of the helicopter.

Second.
Inspect the tail rotor hub, make sure the pitch change yoke is hooked up to the leading edge of each tail blade.

Third
Make sure you only have 1/4 twist in the belt.


Forth.
Give RIGHT rudder, the servo should PULL the rod frontwards, if thats wrong reverse channel 4.

Last.
Pick up the heli and turn the nose LEFT, ensure the servo PULLS the rod frontwards, if thats wrong flip the NOR/REV switch on the GYRO.

Do these checks carefully, dont see what you expect, pay attention to whats going on. You are missing something simple.

Sarosh

Last night after i posted, i checked back again later before i went to bed and tadawson posted saying about the rev swtich on the gyro, so i decided to check it out, because i know its been on normal ever since. and viola!!! it worked! haha how silly is this, a simple switch solves everything! lol. must have hit it in rev before when i was switching DS a few days ago when i got a successful flight.

Tried it today after work, had to rush home and get it out of the garage, and fired it up, wow had so much fun on one tank. now waiting for a friend to respond then go flying.

There is one small issue, it seems to like to drift right, not the tail, the whole thing, i tried trimming it, but when i do that, it seems to adjust too much then it drifts left instead. Is there a way to adjust how much the trims adjust?

Also other thing, the tail likes to go right from time to time then end up 90 degree heading from where the heading was at when i orginally lifted off. What causes the tail to drift right?

What is the normal length on a tank of gas hovering like 3 ft off ground, and also the TX started at 10.5 volt and now its at 10.0 volts after a tank of flight. it seems to go from 11.1 to 10.5 pretty quickly.

Thanks guys very much for the help!!!

all i need to do now is get it to hover in the exact same spot, then start basic manuevers and forward flights.

Sarosh

Well, it flies great now, got everything pretty much setup well, can hover much better now, and move around pretty good. well heres a mistake i just made today, i decided lets try forward flight. big mistake! why? i forgot to practice hovering with the nose toward me lol... so the heli is flying 40 ft high and not too bad but also i forget that helis fly like planes while in forward flight. so i kept using the rudder to control it, but it was making it harder! lol after it got so far away, i tried to get it back, with a few close calls like it doing steep roll. almost clipped a tree, when i did that it went into steep roll ended up 90 degree, and i pulled more left rudder which sent it down to the ground! after that my friend told me that i should use the elevator instead, just like planes. lol oh well. Only thing it costed is a blade.

Everything looks fine, all controls move normal. so i need to order new blades. I bought a new blade set last weekend but it turns out its 550 mm blade not 600 mm. so i dont have a extra blade. i think 550 is too short for the R50. I have a 600mm carbon fiber on order from saturday, supposedly to be at the store friday. then theyre calling me and sending it to me. wont see it until next week. bummers. no more flying for at least a week. unless someone tells me 550mm will work.

Next time i'm practicing hovering with the nose toward me before attempting any forward flights.

My friend took video of the entire flight. so should get copy from him then post on youtube, and i will post the link here for you guys to see.