Spartan Quark Not Working

[migreig]

Hey everybody,

Had this gyro for about a year now. I was never able to get it to hold my trex 450. I recently installed it on a new hk 450 build and having same issue. It just doesn't hold the tail at all. I've tried everything I can think of and it.Just won't work. The light is solid blue, programming goes fine, and then I take off, and it's round and round in circles I go.

The issue won't be on the chassis/tail as this is a brand new machine with the same issue, but I'm not sure what else to check!

I'm running a basic hk450 with a dx6i, futaba 9257. Any help is appreciated!

[Bob O]

Does the gyro compensate properly on the bench?

[migreig]

Yes it does. That's what makes this whole thing so confusing. Appears to be fine on the bench. End points set etc, and as soon as a spool the thing up it's like it just shuts itself off.

[ahahn]

Usually spinning on the ground means the compensation is backwards. I know you said you checked it, but ....

So when you swing the tail to the right (nose swings to left), the leading edge of the tail blade moves toward the tail boom ---as shown in the drawing on page 16 of the setup guide?

Sorry to ask, I don't mean to be insulting, but the Quark is a great gyro. It is possible that it is bad, but that is a long shot. But of course it can happen

[migreig]

Originally Posted by ahahn

Usually spinning on the ground means the compensation is backwards. I know you said you checked it, but ....

So when you swing the tail to the right (nose swings to left), the leading edge of the tail blade moves toward the tail boom ---as shown in the drawing on page 16 of the setup guide?

Sorry to ask, I don't mean to be insulting, but the Quark is a great gyro. It is possible that it is bad, but that is a long shot. But of course it can happen

It's not insulting If I had all the answers, I wouldn't be asking here

I will check into that, and in the meantime I've posted a video that explains what's going on more accurately. Thanks for any help!

https://www.youtube.com/watch?v=Lpp0JI4jLVU

[James Recard]

Have a close look at the left side of the tail box.... How much shaft is hanging through ?.. your tail shaft gear might be in the wrong position on the shaft...

[Bob O]

mig,

It definitely looks like you have an insufficient amount of available pitch for right rudder. Here's what I would do:

1. Make sure the pitch slider bushing is fully seated.
2. Try flipping the tail grips so you have trailing edge control, see if that gives you more
right rudder pitch.

If you flip the grips, keep in mind you'll have to reverse the direction of the rudder channel and flip the tail blades around. You'll also want to go back into the gyro programming and set that back up from scratch. The small plastic pitch control links on the tail slider fork will need to be flipped too in order for things to mount up properly.

Regarding the belt idler pulley, I'd remove it. You'll need to set belt tension again.

Nice video by the way, I like your comment about "both hands"....LOL!!!

Let us know how you make out with this.

[Bob O]

https://www.helifreak.com/showthread.php?t=628930

Sent from my phone

[migreig]

Thank you Bob, looks like that guy had exactly the same problem, I will try flipping the grips today.

[Bob O]

Okay, let us know how it goes.

Sent from my phone

[migreig]

Well this is embarrassing. I went to "flip the grips" today, and it turns out I have no idea how to do that. I assumed it meant to swap them but they're exactly the same so that wouldn't have any meaningful effect.

How does one "flip the grips" on the tail blades?

Thanks for all of the help.

[migreig]

I suppose it might have been clever to assume that the issue was with my $30 helicopter and not my $130 gyro....and that's the case.

It seems that the divot drilled into the tail shaft is actually drilled in the wrong place. I loosened the set-screw and moved it out a few millimeters which gave enough room for the blades to properly compensate both ways...flies like a champ now.

I just need to order a decent shaft or sort out how to drill a new hole in the HK one.

Thanks for the help everybody.