Roll when inverted

[Dylan Hudock]

Hey guys, I recently made the upgrade to flybarless with the dfc head and beastx. Flies great, but the only problem I have is when inverted, it wants to roll with a collective input. It is not only not a straight climb out, but just when hovering inverted and give a quick collective input, it rolls a bit too.
I have kst ds315's on cyclic and the 3m 3010 gray tape, have tried 1 and 2 layers and and also a velcro strap. I am new to flybarless/ beastx and any help would be greatly apppreciated!

[HeliAxe]

Two things that come to mind.

1) Your cyclic trim may be slightly out - Parameter setup A.

It may be slightly out that you may find it hard to notice during short hover tests but the heli will climb out at an angle (slight roll) under load such as a hard vertical climb, either inverted or upright.

Re visit Parameter menu A closely to rule it out.

2) Your Cyclic gain may be too low (Dial 1). In your highest head speed, raise your cyclic gain (Dial 1) until you get the heli shutter under quick cyclic inputs then lower the gain from there until the shuttering stops after hard cyclic inputs. Just like how you adjust the tail gain.

See how you go with these two ideas.

[trexpro]

What about your COG

[Dylan Hudock]

How would I go about adjusting parameter A to give a straight climb out inverted, without messing with how it climbs upright. I haven't touched parameter A yet. I am out of town right now so next time I can fly is friday but I will slowly turn dial 1 up. I had already done that until I got a wobble on elevator tic tocs and then backed off slightly. The CG is dead on.

[HeliAxe]

Q: "How would I go about adjusting parameter A to give a straight climb out inverted, without messing with how it climbs upright"

A: You can't. There are no separate adjustments for upright Vs inverted.

Also, don't confuse a cyclic wobble with a cyclic shutter. The cyclic may wobble if you have Dial 2 too high as your cyclic input overshoots and tries to correct. So as you said, slowly increase Dial 1 until you get the shutter and then reduce Dial 2 to see if that reduces the wobble. Hopefully this may help.

I would also remove the velcro if you haven't done so already as this may be restricting the vibration absorption properties of the 3M foam tape. That’s old school nitro days. Not needed with modern smooth electric helis and more advanced adhesives.

Just trying to throw ideas at you...

[Dylan Hudock]

Alright thanks I will definitely give that a try and report back