When you say the tail end wobbles does it wobble side to side, or wags as its more commonly known? If so the the gain on the gyro may be too high.

If it's a slow side-to-side wag then the gain might be too low, if it's a fast wag it could be too high. The 401 has
a pretty wide 'sweet spot' so it is usually quite easy to get a workable gain setting.

What tail servo are you using?

In my experience the Raptor tails are usually not much trouble but the linkage needs to be as smooth
as possible. The Raptor tail linkage is never just silky smooth there's always a bit of resistance
from the guides the pushrod goes through. One thing I discovered is that the plastic guides
can 'catch' a bit sometimes and the cure for this is to very gently reem each side of the hole
with an exacto knife, just enough to put a very slight bevel on the inside of the opening on
both sides, this keeps it from grabbing if the guide rocks a little bit (hopefully you can
visualise what I mean).

I always feel how smooth the linkage is by disconnecting the link from the servo and moving
the pushrod to feel if it binds or anything. There is generally an optimum placement
of the plastic pushrod guides where it all moves as smooth as it can. Once you find
the best position for them then make sure they cannot move around. I usually put some
clear tape on the boom where the guides go so they fit snug once I find the best
placement.

Hi, The servo on the back is a S9404, Its not a slow wag, its a super fast wag and quite scary lol.
I was looking for the gain on the 401 the other day but was not sure which one it was as I do not have the manual, I have just had a look on the net so I take it the control delay trimmer is the gain.

I just put a new boom on and another tail rotor off another heli , still did it, I will give the gyro a turn tomorrow see if that sorts it out hope so, all the linkages seem to be fine.
Thanks for your help, I will let you know tomorrow what happens.

No the delay is not the gain. The gain is set from the TX. There are two connectors going into the GY401, one
of them is the rudder channel, the other is the gain control and it is usually connected to the gear channel
on the TX.

On the face of the 401 there are two switches and two rotary pots. from left to right they are;
switch1 = DS (digital servo) on is up and down is off. With the 9404 servo I think it should
be set to 'off'.
switch2 = DIR This is for the direction of the gyro 'sense'. This one is set correctly on yours
or it wouldn't be a wobble it would be spinning wildly.

Pot1 = Delay. This is for slower servos that cannot react fast enough and may result in a bit
of a bounce on hard stops, the delay helps prevent the bounce.
Pot2 = Limit. This is for setting the maximum throw of the servo so that the tail slider
can go as far as possible but the servo will not try to push beyond the limits and
start binding.

The S9404 servo is a bit older and is not up to the standards of modern tail servos
so it's hard to say how good it can get. I would think it will work for very basic flying
but ideally a faster servo will give you a lot more holding power.

Now, back to the gain issue again. What transmitter are you using? There may be
different ways to adjust the gain depending on the TX features.

In the manual, set the delay to 0 for fast or digital sevos and that is what it was set at, I did turn it up but it did nothing..
Yes in my manual for my transmitter ( futaba 2.4 ghz ) set the gyro for the 401 which I did but I did not like it cos when you push the rudder stick it does not go back to the middle by itself.

Also in the manual it says Sensitivity switch ch5 ( up position ) Gyro +80% and switch down 60% normal mode,, should I try this then ?? ,, what is AVCS when the switch is up ??.

Yeah, the delay is not the problem so changing that is not likely to do anything noticeable.

The key is the gain channel. AVCS is heading hold, which is what you want. The GY401
should show a steady red light when heading hold is activated. Don't worry about the
gyro not going back to the centre when you release the stick, this is normal.

I am not familiar with the Futaba TXs so cannot help there as to exact settings
but basically the travel adjust on the channel where the gyro gain is connected
will determine the gain setting.

This sounds like something that would ideally be helped greatly by going to
a local club and having an experienced heli flyer look at it because it's
not so easy to build a puzzel piece by piece on here when all this stuff
works together and everything affects everything else. It sounds like
if the mechanical setup is correct that it might just be a gain issue
but we could be chasing this around in circles if other things need
adjusting as well.

I am betting it will solve it tho cos I have tried everything else, anyway I like it to centering by itself cos its what I am used to .
So your saying put it in AVCS mode which is 80 %, what is ACCS ??,, you know I can not fly 3D

Oh yea the red light stays on...

I get it, been having a read :-) Well I will give it ago tomorrow if I can, thank you for both of your help, very greatful.

It sounds like you're probably close. The idea of heading hold is bascially that the gyro will try its best to keep
the tail right where you left it until you actually move the rudder stick. It should not be drifting one way or
the other by itself and for me this is an intuitive way to fly. Some people like rate mode because the tail
will 'wind vane' in forward flight and swing around in turns etc. but to me this is very annoying. You can see
how this works by trying some of the scale helis in Phoenix.

To begin setting the gain you could start with the 80% figure and then if you're getting a fast wag
back it down a bit, if you get a slow wag or the tail feels 'mushy' and not holding solidly then
bring the gain up. I usually do this a few clicks at a time and see what happens. Hover a bit
and if you have a wag then land, change the gain one way or the other and lift off again
and see if you're making the wag better or worse etc. usually just a few bits of trial and error
and you're there. Just watch very closely, anytime you're changing things with the tail, when
it starts to get light on the skids if it looks like it's going to spin around then something
is wrong.

With the GY401 the servo travel limit is set for both directions by the one pot on the gyro
so you have to watch the pitch slider for the maximum travel both ways and adjust
the linkage mechanically. Just make sure the servo is not binding at the end points either
way trying to push the tail slider farther than it will go.

I don't know what ACCS is :-o

Good man thank you, you have fixed my problem yyyaaaa lol. Hovers really nice BUT can I pick your brains a little more .
After a few minuets of hovering, it starts losing power and just drops down to the ground :-(
I have turned the screw both ways to make it rich and also the other lean, still losing power.

hi michelle, my rappy 30 used to loose power when it got hot on 10% nitro so i upped it to 20% and now its fine

Hi Dave, my mum lives at Malton so not far away from you, in my younger years , I used to go drinking at sunny Scarborough.
I am already putting 20% fuel in it, to be honest, its turning into one big headache this heli, looks brand new also the engine but I don,t no what the last person was like with it as I got it off the bay.
I am thinking of just putting a new engine in it Monday so I know its good, it just dies after a few minuets even when you give it more throttle nothing.
Anyway its a big learning curve.

it defo sounds like an overheating problem but someone else may have other ideas but as it came from fleabay you may be wise to invest in a new engine