Furion 6 Flybarless Build Pictures

[Eyefly]

Originally Posted by dauste

Not sure if any of you guys have got round to setting up the FBL head yet?

I centred the servos with the little carbon pointer, made up the linkages with lengths as per the instructions and I can't get zero pitch.

Looks like the servo to swash linkage length is about 4mm too long. I can't screw them in by that much, so I'm wondering if I may need to cut the rods down slightly??

Can you post a pic?

[dauste]

Sure can!

OK, so I have centered the servo arms using the carbon pointer and lining up with the small hole on the front servo. (may look a little off, but that's just the camera angle).




And with the servo links at the recommended length of 21mm (they won't go much smaller) I have the driver arms not level and a whole heap of positive pitch.


If I move the swash down to get them level (zero pitch) like this.


Then the servo arms are about 4mm off my centre.




The only way I can make the linkages any shorter would be to grind a few mm off each end of the rods!

[Thrasymedes]

This may be a really dumb question being I do not own one....but I see the M3 bolts are not in the head block yet, do you have the 128-198 pin inserted to set the height of the head block properly with respect to the shaft?

On my other MA birds without this pin the headblock will drop past the hole, thus being too low which would cause your condition shown in pic 3.

[pcskyhi]

I have a Furion 6 FBL kit and have reached the point of installing the main shaft and gears (tail rotor and main gear). I have the tail rotor gear pushed down to the bottom bearing block and the main shaft collar pushed all the way to the top against the top bearing block. This prevents the main shaft from moving up and down but the auto rotation/main gear unit has space to move up and down between the main shaft collar and the tail gear on the main shaft. Has anyone else come across this ? I don't think I should have any play in the drivetrain and there are no shims to remove the play.

[dauste]

Originally Posted by Thrasymedes

This may be a really dumb question being I do not own one....but I see the M3 bolts are not in the head block yet, do you have the 128-198 pin inserted to set the height of the head block properly with respect to the shaft?

On my other MA birds without this pin the headblock will drop past the hole, thus being too low which would cause your condition shown in pic 3.

LOL, I was thinking to myself, 'I must remember to say that I have the pin in, otherwise someone will pull me up on that!' Just don't have the bolts in yet because I will need to pull it off again.

Originally Posted by pcskyhi

I have a Furion 6 FBL kit and have reached the point of installing the main shaft and gears (tail rotor and main gear). I have the tail rotor gear pushed down to the bottom bearing block and the main shaft collar pushed all the way to the top against the top bearing block. This prevents the main shaft from moving up and down but the auto rotation/main gear unit has space to move up and down between the main shaft collar and the tail gear on the main shaft. Has anyone else come across this ? I don't think I should have any play in the drivetrain and there are no shims to remove the play.

The play is normal and is designed to be like that. The bearing needs to ride up the shaft slightly in order to lock correctly.

[Brian James]

Originally Posted by pcskyhi

I have a Furion 6 FBL kit and have reached the point of installing the main shaft and gears (tail rotor and main gear). I have the tail rotor gear pushed down to the bottom bearing block and the main shaft collar pushed all the way to the top against the top bearing block. This prevents the main shaft from moving up and down but the auto rotation/main gear unit has space to move up and down between the main shaft collar and the tail gear on the main shaft. Has anyone else come across this ? I don't think I should have any play in the drivetrain and there are no shims to remove the play.

Dauste is correct. The auto hub/main gear must be allowed to float, otherwise the autorotation one way bearing will not work correctly.

[dauste]

So no real answers here with my issue??

I'll have to turn to my friend Sherlock on this one 'when you have eliminated the impossible, whatever remains, however improbable, must be the truth?'

... so... all things being equal, servos are centred correctly, servo to swash links are the recommended length, head is bolted on at the correct height.. but still the geometry is not correct.

Can someone please let me know the main shaft length measured from the flat top area of the top bearing block to the top of the main shaft? I have 98.8mm....

[prototype3a]

Does the "geometry" really matter? They are just swash driver arms.

[dauste]

Only that they are linked to the swash height and therefore the blade holders and as they are give about 5 degrees of + pitch. So it needs straightening out. If I drop the servo arms to get it level then I'll get uneven throw from the servos.

[prototype3a]

Ahh.. I misunderstood your problem before.

[Brian James]

I am kind of perplexed to hear of the issue you're having.

The swash followers are are just swash drivers, and as long as you're getting 0 degrees pitch at mid stick, you should be fine. The other option is to shorten the servo to swashplate linkages a few millimeters.

[Thrasymedes]

By pic number 3, even if you got it to read 0 pitch at the blades, you would have a ton of negative and far less positive travel. The swash center ball would bind, or at postive with some cyclic the swash would start binding on another part. The servo to swash links need to be shorter. Seems like the only option on your end would be to dremel a little off each end like you said.

[dauste]

My conclusion was to mechanically shorten the links. The only other very unlikely but possible explanation for this is that the main shaft is too short!! That's why I was wondering how much should be standing above the bearing block.

[pcskyhi]

Thank you dauste and bgjames111 for your quick reply. So where do you seat the pinion on the motor shaft, do you seat the pinion with the main gear pushed up, down or in the middle?

[dauste]

Let gravity be your guide!

I don't suppose you could measure your main shaft length for me could you? Just from the top of the bearing block to top of shaft. Thanks!

[Thrasymedes]

What's a guy gotta do to get a measurement?

Dauste, if I had one man I would get that info for you pronto! Have you tried e-mailing Bobby Watts, I bet he would get it for you?

[raptorwoody]

If my main shaft ever gets here I would give you a measurement. The mainshaft is all I am waiting for. It should be here tomorrow so if you do not have a reply by then I will gladly get you one.

[dauste]

Originally Posted by Thrasymedes

What's a guy gotta do to get a measurement?

Dauste, if I had one man I would get that info for you pronto! Have you tried e-mailing Bobby Watts, I bet he would get it for you?

I know! The women I know are always more than willing to help. My usual response is 'waddya mean that's not x inches'!

I was hoping Brian was just going to dive in the parts bin with a ruler.

Originally Posted by raptorwoody

If my main shaft ever gets here I would give you a measurement. The mainshaft is all I am waiting for. It should be here tomorrow so if you do not have a reply by then I will gladly get you one.

Cheers dude, I'll be shortening the links come the weekend otherwise. Have the rest of you had no problems with this?

[pcskyhi]

Originally Posted by dauste

Let gravity be your guide!

I don't suppose you could measure your main shaft length for me could you? Just from the top of the bearing block to top of shaft. Thanks!

I take it you mean set the pinion with the auto unit/main gear resting on the bottom bearing block.

the approximate measurement from the top bearing block to the top of the main shaft is 98.29mm.

[dauste]

Yep, set it at the bottom. Thanks for that measurement, that is about what I have. I would be interested to see if you get the same issue once you set the head up.