Trex 500 Maiden and my 2nd flight ever!

[Eckchaz]

I couldnt wait any longer.. starting this hobby 2 months ago and replacing the Mini Titan after 1 flight.. I had to try the 500 dispite the wind, damp and cold today, as I couldnt bear her sitting on the shelf anymore!!

Even though this is my 2nd flight ever and the 500's maiden.. I was amazed at how much better/stable this Heli is... On the Mini Titan, I kept cutting the throttle as it was going all over the place and never took it more than a foot of the ground. But with this, I was having steady hovers around 7ft of the ground and holding it well in my garden.. I was amazed what I was doing!.. Can belive the small difference in size has made such big difference in flying, or am I being dillusional?!

Also, I noticed that when spooling up and about to take off.. the tail has a fit and wags like mad , I aint got a clue what this was so flicked the Gear switch on the DX7 (after flicking other ones and the light went red on gyro instead of green?) this stopped the severe wagging but on take off.. I have to apply (I think) left rudder stick to keep it straight.. Never the less.. I still enjoyed my 2nd ever flights!!!

Woo hoo! Might spank some more money and get a 600 now

I Love it I love it!!!

[siloseven]

sounds like your gyro isn't set-up correctly if you need to apply any rudder to keep the heli straight. The gyro light should be green for heading hold and in this mode it should keep the heli pointing in the same direction until you apply rudder. If you're taking off with it in rate mode (red light) then it will spin or need rudder input to correct.

[Eckchaz]

sounds like your gyro isn't set-up correctly if you need to apply any rudder to keep the heli straight. The gyro light should be green for heading hold and in this mode it should keep the heli pointing in the same direction until you apply rudder. If you're taking off with it in rate mode (red light) then it will spin or need rudder input to correct.

Yeah, I've been researching to find out what it is.. but getting very confused.. as i'm a newbie

When light is green, it wags like mad.. and when it takes off.. it spins round and dont stay still.

When light is red, it dont wag but need a little rudder as mentioned but stays still.

Dont think I'm being stupid but it seems the my gyro rates are reversed? Can this happen? Also, Just read on other posts about the gain setting.. I just tried messing around with this on my DX7 but its all greek to me.. I think I've got it right

Gyro Gain is in Gear - So on DX7 Gear = Gear
Read users are starting about 16 in HH to 67 in RM? and heres where i'm getting lost.. where on the DX7 menu to I adjust the gain.. is it under GEAR in Travel adjust?..

If so, Its got + (plus) & - (minus).. If I set the

Gear in 0 (Belive HH mode) = +25%
Gear in 1 (Belive in R mode) = -67%

is this the correct way off setting the gain?

[Mart61]

Congrats on your maiden and successful hoovering.

[Eckchaz]

Congrats on your maiden and successful hoovering.

Lol.. just noticed my typo!! I didnt take the Dyson out.. its was the 500.. honest!!

[siloseven]

if it's wag, ie, fast back and forth a few degrees, then it could be that your gyro gain is too high. If the heli spins around then it's more likely to be the mode set-up

It sounds more like a gain issue from what you describe but I can't help with the transmitter settings as use a different model. May be someone else can help you with that

[Eckchaz]

if it's wag, ie, fast back and forth a few degrees, then it could be that your gyro gain is too high. If the heli spins around then it's more likely to be the mode set-up

It sounds more like a gain issue from what you describe but I can't help with the transmitter settings as use a different model. May be someone else can help you with that

It wags side to side.. and it spins round.. on the green light.

Gain to high & mode set up??... all a different language to me.. but will persist.. then trial and error next weekend!

[gazza]

Yes mate it sounds like green is HH and red is rate mode.
Rate mode is rarely used, except for when setting up mechanical neutral on the heli.
You need the heli in HH mode for the gyro to initialise after power on.
Give it a few seconds then switch into rate mode. Spool up and take off into the hover (Facing the wind) This is important
If the heli rotates left at the nose on takeoff, land immediately and adjust the pushrod length to move the tail blades in the same direction you had to move the rudder to maintain zero rotation. So, if you had to move the stick right, observe which way the tailblades move when pushing the stick right and either lengthen or shorten the tail pushrod a couple of turns to get the tail blades to move the same way.
Now take off again in rate mode and see what happens. You may need to repeat the process a couple of times until you get zero rotation on take off (Or as near as damn it)

Now onto the DX7...

You want roughly the same value in both rate and HH modes.
45% is a good starting figure, and yes it is in the travel adjust menu under 'Gear'. Simply flick the gear switch to select Rate or HH modes (+ & -) In the travel adjust menu. Obviously, never adjust these while the heli is sat screaming its head off in front of you!!
The wagging You're experiencing is due to the gain being too high in the travel adjust menu. As mentioned, 45% is a good place to start.

Oh, and don't forget to reset the physical travel limits on the tail pitch slider after You've finished adjusting stuff!

If you fancy a chat mate PM me and I'll be happy to talk you through it on the phone.

[waveydavey]

Your gain Eddie is how quick the gyro commands the tail servo to react to an input, a wag can be caused by the gain being too high in heading hold mode, which is where you should be. Have you got the remote gain adjustment on your gear chanell, channel 5? If you have great your changing the right limit if not your not doing anything. Basically the tail servo is being told to change because of the wind etc and because the change is quick the gyro realises that it's overshooting and puts in the reverse to the servo resulting in this back and forth movement. You need to drop the gain by the sound of it until the wagging stops. Don't use trial and error it will end in tears, read everything you can on the gyro you have and how to set the tail up.

[shikari_chaos]

In the past I've been told:
fast wag = too much gain
slow wag = not enough gain.
I've been told by several well informed folks that "gain" is actually how far the gyro tells the servo to move, not how fast. BUT in effect it appears to be faster because It's moving the servo further in the same time frame.. a little confusing to grasp but basically the gyro moves at speed "X" (whatever the speed the servo is capable of) and the gain is telling it how far it should push/pull the servo. plus you've got gain on the transmitter and "true gain" so be wary of what gain value people state and whether it's at the gyro or on their TX. Hope that helps!

[chris jones2.4]

In the past I've been told:

slow wag = not enough gain.

or slow tail servo

[shikari_chaos]

Aww yes but as I'm pretty sure Eckchaz went for a GP750/Ds520 as stated in his previous thread about gyro/ servo choice I'm sure that isn't the issue he is encoutering but a valid point none the less

[Eckchaz]

Aww yes but as I'm pretty sure Eckchaz went for a GP750/Ds520 as stated in his previous thread about gyro/ servo choice I'm sure that isn't the issue he is encoutering but a valid point none the less

Yep, I did ask about the combo before buying and it is the setup i've got!

Have you got the remote gain adjustment on your gear chanell, channel 5? If you have great your changing the right limit if not your not doing anything. You need to drop the gain by the sound of it until the wagging stops.

Thanks mate, I have got it in channel 5 so hopefully i'll give it a shot and get it sorted!

Sorry Gazza but I got aload off questions for you

You need the heli in HH mode for the gyro to initialise after power on.
Give it a few seconds then switch into rate mode. Spool up and take off into the hover (Facing the wind) This is important

Why HH to start up and then switch to RM? Dont I just stick to one or the other? And also why is it important to face the wind?

adjust the pushrod length to move the tail blades in the same direction you had to move the rudder to maintain zero rotation.

Now onto the DX7...

Oh, and don't forget to reset the physical travel limits on the tail pitch slider after You've finished adjusting stuff!

If I adjust the pushrod length, wont this change the travel limits on the tail servo? And If I do get the pushrod length right and then go and adjust the travel limit on the gyro afterwards, wont this then change what i've just tried to correct?

Now onto the DX7...

You want roughly the same value in both rate and HH modes.
45% is a good starting figure, and yes it is in the travel adjust menu under 'Gear'. Simply flick the gear switch to select Rate or HH modes (+ & -) In the travel adjust menu.

Cool, I've got the right place to adjust this. Now what I posted before

Gear in 0 (Belive HH mode/Green Light) = +25%
Gear in 1 (Belive in R mode/Red Light) = -67%

From the above what does the + & - mean and have I got the modes right? and the 45% you mentioned as a starting point. Is it just the "45%" figures I should be looking at and disregard the + & -, so put both amounts at 45%?

I'm so sorry for being annoying!

[gazza]

Lol no worries bud

Right..

Regarding initialising the gyro it needs to be in HH to initialize for flight. Whether it matters or not if just starting off in rate mode I don't know..Probably not. But, it's a good habit to get into anyhow when using the gyro in HH mode only.
You can confirm which mode you are in and which colour light applies...(The instructions will tell you anyway)
The easiest way is to power up the TX and then the heli. Without touching the throttle, or better still with Throttle hold applied, give full left rudder on the TX and observe the pitch slider. It will move to the end of the tail shaft. Now let the rudder stick spring back to centre. Now do the same but with right rudder on the stick, and release back to centre. If the pitch slider moves quickly back to centre also, then you are in rate mode. If it more or less stays where it is over on one side then you are in HH mode.
You can also prove this by picking the heli up and rotating it. Rotate the heli through 90 degrees yaw and put it straight back down. If the pitch slider is hard over on one side of the tail shaft then you are in HH mode. If it has returned to center then you are in Rate mode. (Also referred to as Normal mode)

It's important to face the wind as the heli can act like a weathervane in the wind when in Rate mode. A side on wind can cause unwanted yaw hence not giving a true mechanical neutral indication.

Adjusting the mechanical neutral at the pushrod will effect the physical endstops programmed into the gyro but not vice versa.
You always have to adjust the end travel limits after adjusting the pushrod, as you will have inadvertantly increased or decreased the travel movement ratio during adjustment of the pushrod. Adjusting the travel limits afterwards will not affect the mechanical neutral You've just set up via adjustment of the pushrod as you are not breaking into the mechanics in any way, just setting the travel limits on the gyro.

The +&- figures in the travel adjust menu don't mean anything. They just signify the switch position. Don't confuse them with the plus and minus figures in the swash menu! They DO mean something It should stll be set for 45% in both plus and minus positions (Rate and HH mode)
Too high a figure with the switch in HH mode and the heli will wag for reasons already explained.
Yes, just concentrate on the % figures - ie 45%. If the tail holds okay in HH mode after adjusting mechanical neutral then try 50% and so on. Once the heli starts to wag back off a few % until it stops. You're looking to get as near to the heli wagging as you can.

If the gain is too low in HH mode then the tail will not hold and you will get yaw drift.

If the gain is too high in Rate mode, then the gyro will fight any rudder input you put in. If the gain is too low then the heli will just piro in one direction or the other (Depending on the mechanical neutral setting).

Hope this helps

[waveydavey]

For a bit of technical info and how the gain relates to the speed of the servo read the following Please read.