Phill86

Hi.
Very happy with my B400, taking it easy, no crashes yet.
I have very gently touched the tail down harder than a normal landing but nothing to think there would be any damage.(on grass)
When inisializing and checking all servos work etc I noticed that if I moved the rudder to the left and right it moves fine to the left and returns but if I move it to the right it goes there but touches the casing (125 in parts list) and very slowly tries to return.
It works fine if I move left right left right under power but wont return on its own.
There is no damage that I can see.
I read somewhere that it should not touch the tail case which it is so I need to adjust it.
Please could someone guide me how to do this.
Is it as easy as adjusting the tail pushrod. part list 98 or 96?
I dont know if it is important but when the tail blades are in their normal possition part nuber 123 is not square to the heli it is off to the right a bit.
Thank you for your help.

evdreamer

Are you doing this in HH mode? If you want to check to make sure things are working or setting up the tail do it in standard rate mode.

Nick

cessena1500

I am new to . If I understand right when you move rutter stick to right the tail rotors return slowly. That is the gyros working and is normal. My helicopter lever on the rotors shaft will touch both ends of the casing. but it stops right after it touches. Mine flys great.

evdreamer

I forgot to mention that you can use travel adjustments to avoid hitting the casing or anything else. I just hold the rudder all the way to one direction then adjust the travel until there is a little gap between the slider and an object.

Nick

vince.b

My Feedback: (1)

Is the radio set up for the gyro to be in normal mode in F mode 0 nad Heading Hold in F mode 1 ?
thanks

evdreamer

I don't own a DX6i so I don't know what those are. But there should be a gyro sensitivity menu or something like that. Then there is probably two options under that. You can assign a switch to the gyro, so when it is up it could be in HH and when it is down it could be in standard rate mode. Then you need to know what values will put it into HH and standard rate mode.

Nick

SeaComms

No, for some strange reason they have the stock settings at something like 63.5 and 64 (or something like that, I cant remember exactly) which means it is two slightly different gain settings for HH mode. Normal mode starts at 50% on the TX and increases as you get closer to 0%, heading hold mode starts at 50% and increases as you get toward 100%.

Phill86

How do you adjust the travel?

I think there may be a problem with the gyro. When I plug in the battery with at TX settings set to off or 0 the heli starts to arm, the servos move to their centre positions, but the gyro servo moves off of centre, then gives the armed beep, so it needs adjusting. How can I do this please.

My heli tail all so touches each side of the caseing cessena1500, but when you let your rudder stick go yours will return to centre, Mine doesn't it tries but cant. Maybe the shaft has a very slight bend in it (part 126) but I dont think so because under power it works fine with no hessitation. Im hoping it just wants adjusting.
I hope I explaned it better.
Thanks.

SeaComms

Jump on the finless bob setup videos on helifreak - he has a tail / gyro setup on there that shows the correct operation of the gyro - much easier than trying to explain it, but what you are saying, apart from the travelling too far sounds about right. You can not adjust the travel of the servo with endpoint or trim etc, it is totally controlled in distance of travel by the gyro. The stock 110 gyro has no settings for travel limit, so you have to set it via the linkages - as in, move the link in a hole on the servo and you should be right.

EDIT - [link=http://video.helifreak.com/?subpath=finless/hdx300&filename=tail_gyro.wmv]Gyro set up[/link]

evdreamer

I think the best thing a new helicopter pilot can do is watch finless videos like seacomms was talking about. I would be lost without his videos. You have to register on Helifreak now to watch the videos.

http://www.helifreak.com/showthread.php?t=41692

Nick

Phill86

Thanks guys, watching them now.
Let you know if I sort it.

Phill86

[sm=cry_smile.gif] been trying to sort it all day. my TX batteries have now gone flat. Watched the videos 10 times+. That is what it is doing, ok one way but slow the other direction.

By changing the gyro settings from 66.5 to 54 it moves nice but the trim is out. So i go to the sub trim menu to change the trim and it then puts out the gyro.[sm=confused.gif]
I then start all over again.

I will do it i wont let it get the better of me. Just frustrating knowing it should be easy.
It is the stock gyro, do you think it is ok, sometimes when Im making setting changes it clicks and makes lots of noise. (without the servo arm on it so there is no restriction.
I am trying to do adjustments with all TX switches off or 0 and the gyro switches are on STD and NOR ( as it came out of the box)

Going to get more batteries. Hopefully the break will shed some new light onto it.

evdreamer

If it is a digital servo, that is the nature of them to make noise. You could try this since you are having a hard time. I some times use a servo extension to bypass the gyro. I unplug the tail servo form the gyro and connect it to the rudder channel on the receiver with the servo extension. Then I center the servo up that way. After all of that I hook the servo back up to the gyro and adjust the gain if needed. If it is a digital servo the gyro needs to be on the digital setting.

Nick

Phill86

Whoops[sm=cry_smile.gif][sm=confused_smile.gif][sm=cry_smile.gif]

I had the gyro set to 54 and it seemed to be ok.
I put on the training set and went out. straight away I noticed it was spining to the right so i adjusted the trim., then some more all the way didnt fix it. Just then dont know what I did/happened its on the floor with a boom strike and damaged blades.

The bad bit is, the work that I did to try and fix the first problem still excists as i had to use so much trim.
Will be watching a video on tail/ boom repair now.
As I am starting from a repair is it worth me getting a better servo for the tail? what is the best one for the B400.?

Thanks again for everyones help and ideas.

evdreamer

Are you using the trim on the transmitter or subtrim? If you use rudder trim not subtrim it will mess up the HH gyro to think that you are giving constant rudder input.

Nick

SeaComms

54% gain is pretty much nothing by the way, it is only 8% in Heading Hold and theres no way that will hold it steady. You should be up around the 65% to 70% mark (30% to 40% gain in HH mode). With the stock gyro and servo I had mine at bout 74% with the ball link on the servo pulled in a hole from stock (think it was the third hole from the centre) to stop it from binding.

I then followed the Finless Bob vids to have the servo at centre when the slider was at centre, then in heading hold mode adjusted the sub-trim to stop the creep in both directions. Looked like it was going to be quite steady like that until the aileron servo crapped out and dumped it into the grass.

Phill86

I was using subtrim as the video said to.

Phill86

Ive got a boom and have fitted it. Very surprised at how easy it all went.
When I start up the rotor blades as I get faster i hear a whirring noise,.(not the main rotor LOL) almost like the tension of the belt as it speeds up, although I have not adjusted the tension. I noticed it also did this before i repaired it. (unseen damage maybe)
Has anyone else had this happen and how did you fix it. The belt moves fine so I'm not to sure what its catching at high speeds. How tight should the belt be?
Thanks.

Phill86

Sorted the noise , the plastic covering on the woodies was making the noise at high speed.

The only problem I have now is as I power up it spins to the left. Everything is 90 degrees and centered.
I have put the TX settings back to their default (gyro 66.5 etc.)
Dont understand why it should spin.

Phill86

Hello again.
Watching Bob Whites videos again I noticed a big problem.
If I am right in thinking the main blades should spin clockwise and the tail rotor should spin anti-clockwise up into the downwash of the main rotors.
My main rotors spin clockwise but the tail rotor also spins clockwise[sm=confused.gif][sm=confused.gif] How did that happen? Is it the way the belt twists as you put it onto the cog in the tail casing, going to try changing as that is all I can think it can be.?

Learning all the time.
Thanks for any info.

SeaComms

Yep, you got it.

When viewed from behind, the belt starts horizontal, then twists clockwise 90* to vertical to go around the tail shaft.

Cheers, Dave.

Phill86

All sorted, flys perfect.

Thanks for the support on my 1st repair.[sm=thumbs_up.gif]

Happy ending in the end