Flybarless Swift 620

[desert_flyer]

I decided to convert my Swift from a mild A123 setup to a 10S Lipo, flybarless monster.

With the stock flybarred setup the 620 excels in FFF and aerobatics. It is a very streamlined heli so it likes to go fast. However, even after many tweaks I was unable to get the kind of cyclic response needed for piros etc. So I decided to bite the bullet and go flybarless.

The installation was quite simple. I opted for a Skookum Robotics SK-360 2 axis gyro ($360) because I am happy with my existing tail gyro. The Swift is easily modded for the flybarless setup. I just added longer blade grip balls (to tame the response) and an aluminum swash follower. The Skookum Robotics gyro was easy to setup - it uses a PC interface and comes with a nice manual. The standard settings worked well but I was able to improve things with a little tweaking. This involved increasing the hillier gain and decay. Power is provided by 2x 5S 4270mAh Evolite V2s, CC85HV with the absolute headspeed governor update and Century 565kv motor (which I understand is just a rebadged Z-power Z50) with 11t pinion.

OK, I must admit that I was nervous about this because there have been some incidents with vibration on other helis and the swift can dance a little on spoolup. But I am happy to report that everything was smooth - in fact the swift was much more solid without the flybar. Anyway, the improvement is mind boggling, lets get that outta the way. The stability is rock solid in all orientations and during all maneuvers that I can muster. The cyclic response is locked in at 210 degrees per second, yet the heli is rock solid in upright and inverted hover, even with a stiff breeze. Would be great for a scale setup. In terms of the 3D stuff, I couldn't find any CCPM interactions and no pitching in forward or reverse flight, even during aggressive collective. The setup right now has 14 degrees pitch and 10 degrees cyclic. Finally, it is 6oz lighter and 100 rpm higher head speed without the flybar.

Looks like I will have to convert my everyday flyer Trex 500 next - because I am spoiled now ;) .

[RC Man]

Do you have more details and step by step photos of exactly how you converted the head to flybarless?

[desert_flyer]

RCman,

Sorry, I don't have any step by step pics but I can tell you that it is very simple. Remove the flybar and all associated parts so that you're left with just an empty head. Then remove the blade grip mixer arms and replace with long ball links. Add a swash follower and make sure that it works in the range of motion that you need for the swash. Then use the long links to join the swashplate directly to the blade grips. Then it is just a matter of dialing in the collective and cyclic pitch range using a pitch gauge. Much simpler than setting up a flybarred head.

Slightly better pic attached

[RC Man]

Tell me more about the swash follower and where I can get one. I am just starting to learn about flybarless and I don’t know all the new terms.

[Spidious]

This is a 4 bladed follower. But it should be the same as a 2 bladed follower ?

http://www.centuryheli.com/products/productdetail.htm?currentid=351&prtnm=CN1108

[desert_flyer]

^^ That is the one I used. Seems to work well.

[RC Man]

$50 :eek: that’s a crazy price for that little thing :mad:

I see that we have a long way to go before flybarless is affordable to the average flyer.



:confused:

[desert_flyer]

Yes the stuff is overpriced. Of course you can just adapt the standard antirotation mechanism. If you search for flybarless swift you'll see how this is done. I think wheelhaus has a thread somewhere...

I had another 5 flights today and I can tell you that dollar for dollar this is the best money I have spent on a heli upgrade...

[johnm1019]

can someone explain what a swash follower does?

[rotoraddict]

This is just the thread I was looking for.

I am just finishing up a Swift 620SE. I was so impressed with their 16 & 550SE, that I had to follow on with this one.

I too will be going all out with 10S, the same 650+ Century motor and their 85HV esc...along with top electronics.

I have been wondering if I should go flybarless also. Now I know I will eventually. But first I too want to try it stock.

What blades are you using. Are they the same ones you used when it still had the flybar?

[desert_flyer]

First, swash follower performs the same job as the antirotation pins on a standard head - i.e. it maintains the phase between swashplate and blade grips. You need to have zero phase slop on a flybarless head to get the most out of the system.

Second, I am using rotortech 610s. I recently ditched the century motor and replaced it with a Scorpion 4025 (630kv). The century motor was getting too hot in flight and the Scorpion is providing an extra minute flight time with a slightly higher headspeed, which tells me that the Century motor was somewhat inefficient...