3GX Again

[tourerjim]

Think Align have c*cked up again, i was getting tailward drift on the 2 heli's ive v5'd & found elev doesn't do full collective with pit & aile servos so plugged in to the pc & found parameter 'collective pitch elev precompensation' in flight mode 1 is default 50% but needs to be zeroed to allow elev servo to match the other two servos travel, where swash plate should be level throughout its travel @ 50% then go + - for precompensation it will only work one way as you need to set this to 0% but would be interested if this is same as yours but you need use swash leveler in flight mode to check.

[dogcow]

3GX Again

I think I'm still using 80% for Precomp from my V4.1 settings, swash is level I checked it with a swash leveller after the update.
Still not happy about using max gains and Heli still drifts a little at times (mainly tailward drift like yourself), especially in the wind as I noticed today which is a little disconcerting to say the least.
Still resisting reverting back to V4.1 tho, it must be just some different settings needed.

[coolice]

Hey Jim.

Remember what you see on the bench might not be the case in flight. Ideally we want a level swash plate throughout its range of travel, but in flight the FBL unit will compensate to some degree.

Normally a problem like this can sometimes be traced back to a mismatch in servo horn positioning when at the mid-stick zero pitch position. If there is a difference here, the control balls start their motion at differing point along their arc of movement, the further the servo moves the more pronounced the difference overall.

It might be worth rechecking the servo arm positioning in DIR mode, just in case to satisfy a curiosity.

Hoping to try a model with V5 at the weekend.
.

[tourerjim]

Hey Jim.

Remember what you see on the bench might not be the case in flight. Ideally we want a level swash plate throughout its range of travel, but in flight the FBL unit will compensate to some degree.

Normally a problem like this can sometimes be traced back to a mismatch in servo horn positioning when at the mid-stick zero pitch position. If there is a difference here, the control balls start their motion at differing point along their arc of movement, the further the servo moves the more pronounced the difference overall.

It might be worth rechecking the servo arm positioning in DIR mode, just in case to satisfy a curiosity.

Hoping to try a model with V5 at the weekend.
.

The finding is when in flight & problems is with two heli's Ian & if you pitch pump the more the tail drops, hover just give a slight tailward drift & neg is is fine.
DIR setup is perfect & only shows up in flight mode.

[Grumpy]

I'm still struggling with v5 on my three 3GX helis (500, 600 and 700 size). The bigger ones are worse. I've had to crank the gain pots up literally to the stops to be flyable, plus pump in lots of trim to stop rearward and left drift in hover. On v4 they were rock solid with gains roughly centres and no drifting at all, I didn't change anything other than firmware.

I'm probably going to go back to v4 on two of them so i can at least still enjoy flying, then work on the v5 set up on one heli to see if i can figure out what the issues are and how to get around them.

[tourerjim]

I'm still struggling with v5 on my three 3GX helis (500, 600 and 700 size). The bigger ones are worse. I've had to crank the gain pots up literally to the stops to be flyable, plus pump in lots of trim to stop rearward and left drift in hover. On v4 they were rock solid with gains roughly centres and no drifting at all, I didn't change anything other than firmware.

I'm probably going to go back to v4 on two of them so i can at least still enjoy flying, then work on the v5 set up on one heli to see if i can figure out what the issues are and how to get around them.

When you went through dir did you set your cyclic degrees, you need to be between 8/9 degrees but put gains back to 12th first.
I've always found that gain pots only need to be used to achieve the initial take off then try these settings.

[dogcow]

I always thought using trim on the 3gx was a big no no?
Has that changed?

[tourerjim]

I always thought using trim on the 3gx was a big no no?
Has that changed?

You can use swash mix prior to dir setup for pitch & cyclic degrees.

[coolice]

The finding is when in flight & problems is with two heli's Ian & if you pitch pump the more the tail drops, hover just give a slight tailward drift & neg is is fine.
DIR setup is perfect & only shows up in flight mode.

Evening Mate.

There is a parameter within the PC software to tune out the tail/nose dropping/raising with collective pitch pumps, found on the Flight Mode Parameter 1 tab in V4.

Check your centre of gravity to, as this will effect things when aggressive pitch changes are made, as the heavier end will take longer to react.

I always thought using trim on the 3gx was a big no no?
Has that changed?

Evening Mate.

No, it's always been in the manual that you can use your transmitter trims on the 3G & 3GX. I advise against to using too much, but a few clicks do not hurt. I've even used trim on my Vbars without problem.
.

[coolice]

You can use swash mix prior to dir setup for pitch & cyclic degrees.

Hey Jim.

Not since the introduction of later firmwares where you needed to set the 8 degrees on cyclic.
In the olden days with the 3G/GX you could use your swash plate mix values to increase or decrease flip & roll rates, but not since we need to tell the 3GX where 8 degrees is.
Only adjust your swash plate mixes while in DIR mode and leave them at the values set, not before as it could give you false pitch readings as the gyros will still be active.
.

[tourerjim]

Evening Mate.

There is a parameter within the PC software to tune out the tail/nose dropping/raising with collective pitch pumps, found on the Flight Mode Parameter 1 tab in V4.

Check your centre of gravity to, as this will effect things when aggressive pitch changes are made, as the heavier end will take longer to react.

C&G good, this is the one that adjust tail nose drop/raise.

[coolice]

C&G good, this is the one that adjust tail nose drop/raise.

Evening Mate.

Yes, that's the one. It's zero'd on your screen shot, did you alter it from the stock 50%?
.

[tourerjim]

Hey Jim.

Not since the introduction of later firmwares where you needed to set the 8 degrees on cyclic.
In the olden days with the 3G/GX you could use your swash plate mix values to increase or decrease flip & roll rates, but not since we need to tell the 3GX where 8 degrees is.
Only adjust your swash plate mixes while in DIR mode and leave them at the values set, not before as it could give you false pitch readings as the gyros will still be active.
.

Sorry Ian your right, don't know why i said it like that when i know full well setup has to be done through dir except prior v3.

[tourerjim]

Evening Mate.

Yes, that's the one. It's zero'd on your screen shot, did you alter it from the stock 50%?
.

This is were the problem is if i set it to 50% & pitch pump i get a big tail drop set to to 0% & seems perfect & with no tailward drift in hover & this is happening with my 600e & 250 the only two ive test flown, hoping 450 & 500 will be ready for testing w/end so be interesting if they turn out the same.

[dogcow]

Evening Mate.

No, it's always been in the manual that you can use your transmitter trims on the 3G & 3GX. I advise against to using too much, but a few clicks do not hurt. I've even used trim on my Vbars without problem.
.

Evening Ian,

Thanks for clearing that up, always found this confusing so now may try it without worrying although be careful not to use too much. Maybe a tweak to the elevator trim is all that's needed?
Will be interesting to see if you notice any drifting and higher gains required when you finally get a chance to put V5 through its paces