Hi there, So there I was flying my electric 400 Blackhawk CCPM about two weeks ago and just as I came in to land the rotor head locked up from a pitch link comming loose. Preflight inspection might need a little work. Anyway I have all of the parts now installed and am beginning to rig everything when I realized that I have no earthly idea how to rig the flybar. This style flybar has paddles/blades and I can get them to work on the same plane as each other by using the dry erase marker method, but have no way to rig them to be pulling the same pitch as the blades. The book I have says nothing about this, but I cant be the first one to have to re-track a flybar. Any help would be greatly appreciated. Thanks.

welcome to RCU with your first post... I don't know that particular heli, but usually the flypaddles just stay flat and don't take the angle of the blades.

Hey thanks for the warm recieption. These flybars do gain and lose pitch with the blades and have a form of "H" lever that operates them from the swash plate. There are two linkages involved that are both adjustable. I am going to see if they will work if I match them with the pitch gauge. Initially I just tracked them together before installing the new main rotor blades. Once tracked I installed the mains and tracked them as well. I just spun it up for the first time and that DID NOT work. I just found that I have a servo going to crap and am going to replace all three with a new set of JR's that I have so I will be starting all over with the rigging anyway. Hopefully that will give this thread enough time to get some more hits before I am back to the flybar stage.

i am gathering it is a collective pitch heli if so put the stick at half way or zero degrees on the the main rotors and level your flybars, paddles from there also make sure before you level them your swashplate is level both from the front and side of your heli if you do this and everything else is correct it will fly beutifully. also you are correct in saying that the paddles do move during flight only not as much as the main blades, but they only move during cyclic movments and aeliron movents if you increse or decreses the collective they do not move they remain level

actully can someone spread some light as to why our helis have flybars and paddles, what purpose do they serve?

Physics ...

Two reasons ... stability and controllability.

Stability: The weighted paddles act as a gyro. When the paddles are 0 pitch and spinning, they tend to want to stay on that plane ... they don't want to teeter. So it keeps your cyclic stable when the cyclic is centered. If your heli happens to take a little gust of wind, the heli will move relative to the spinning paddles which induces a pitch change on the main rotors (remember that it is the flybar teetering that changes the pitch on the mains ... not the paddle angles). This induces a pitch change which will help stabilize the heli. There are some full scale helis that have a stabilizer bar and used for the same reason.

Controllability: We have to change the collective pitch and the cyclic pitch to maintain control of the heli. This requires a tremendous amount (relative to RC helis anyway) of force to make those pitch changes because you are working against the forces of physics ...
The problem is ... our standard size servos (even the top dollar high torque kind) simple don't have the muscle to do the job unless you want to fly around in scale mode all the time (not that there is anything wrong with that).

So how do we fly then if our servos are not up to the task? We harness the energy of physics. We create a flybar system where minute changes in paddle pitch produces a huge amount of teetering force (again, it is the teetering that changes the pitch of the main rotor blades). We connect/mix this teetering leverage to the main rotor blade pitch control and bingo ... we cycle the main blades with the leverage of the flybar.

Ever notice helis that use mCCPM (ala TT Raptor) that they have a long lever that the pitch servo operates. The servo needs the mechanical advantage of the long lever to over come the force needed to push the pitch through its paces. eCCPM helis don't have this lever but they are also combine the force of 3 servos to produce collective pitch changes.

Are there servos that can handle the force? Sure but you can't fit a 1/4 scale (or bigger) servos in our helis and they don't make servos in standard size that can produce the force necessary ... yet.

Until then, we use the flybar systems.

thanks for that great explaination, it cleared alot of confusion up, but how do multi bladed heads keep there stabilty and how do servos move all those rotors if they have no fly bar and paddles. sorry for all the questions, they really are complex machines and the more you understand them the easier they are to build and set up

you might try asking your flybar q over here
http://www.rcuniverse.com/forum/m_43..._1/key_/tm.htm

Generally, flying a mult-bladed head doesn't involve the radical pitch changes that we need to do 3D stuff so the servos can handle it.
I'm not an expert on these heads but if they were configured in a 4 servo eCCPM setup, you would have the forces of 4 servos teamed together.

thanks, anyway have you got your flybar and paddles working yet JKEP44

I rigged them at flat pitch to the blades (center travel on the xmitter stick) and used the sorry excuse of a pitch gauge that I recieved with the heli to even everything out. I have to go to the hobby shop tomarrow and try to get some screws that will connect the tiny ball links that I have to the larger DS JR micro servos that I installed today and do it all over again. I think that I will pick up a decent pitch gauge while I am there. Thanks for the help, and I will post something when I know how it all turns out.

Multi-blade heads are notoriously hard to fly which is another reason we use fly bars. It offers more precise (and instant) control to the collective than simply adjusting collective does.

I believe that most multi-blade flybarless heads usually use blades with weighted tips to aid in stability.

Instead of the screws I needed I found it much easier to buy a set of T-REX ball links and just thread them on to the ends of my linkage arms. The new pitch gauge made a world of difference and the heli now flys great again.

Well on mine, I just do it the old fashion way. I built a mini tracking flag and get two different color grease pencils from a craft store. Wooden paint stirs are great. Run a few layers of masking tape along the stick. let it overhang abut a 1/2 inch. Dont want the blade hitting the stick. Blade needs to hit the tape. So you make the end of one blade with one color and the other blade, another color.

I put some sort of weight on the skids so it wont lift off and start it up. I take a few different hits but mainly about half throttle, she's spinning pretty good. If the tracking is off, you'll see two different colors on the tape.

You can adjust the pc links any way you want but you need to bring the colors together. I usually move the lower blade up to the higher. Doing this depends on where you links are. If they are on top of the head, need to lengthen. If they are below, shorten. Very simple thing to do.

Thats TOTALLY not tru anymore. Ever seen a Flybar-LESS RC heli fly? theres a ton of guys doing this conversion to there heli's and getting very good results from it, its just alot of set up to get them to fly like a fly-bar'd heli. But yea, everything else is true for what u have said.

Thank you for responding to a 5 month old post. I did post (5 months ago) ... " ... they don't make servos in standard size that can produce the force necessary ... yet.". The technology in the RC heli hobby has grown tremendously in the last 5 years ... look at the electric heli as an example.
Never would have thought that you'd see 50 and 90 size electrics ... but look at us now!!!!

So yes ... if you go back in time you WILL find a post that is NOW untrue. Thanks for the update.

Yes ... I've seen a few flybar-less helis fly ... and they were ALL in large, SCALE helis and they were doing very scale flying.
I've never seen a flybar-less heli being flown like a full up 90 size extreme 3D rig ... but I don't get out much

Maybe 5 months from now ... this will also become untrue.

NOT EVERYONE looks at the date stamps to see when a post was made. this thread was #2 in the list when i saw it (which indicates fairly new to me). so sorry you feel like you were singled out in the crowd and made to feel like a retard, but then again your great way of replying to something i just said was untrue made it relevant you were embarassed..

Ohh and just so you can see a flybarless "full up extreme 3D rig" here ya go.. Its a Trex600 there's a few nitro's and some 90 size helis to i just haven't found the links again.

[link=http://www.brovictv.com/HDVIDZ/JasonTrex600EflybarlessHD2.0NEW.wmv]http://www.brovictv.com/HDVIDZ/JasonTrex600EflybarlessHD2.0NEW.wmv[/link]

I did it! It was me.

I could be wrong but I think the flybarless rigs just need a few extra gyro's. I could also be wrong again, but I think if you look on the lower left side of that heli the two objects strapped on with the align straps look like gyro's (or maybe they are something else, but they look like they have servo leads to them).

Actually.... and just to keep the post going...

The flybar moves 90 degrees BEFORE the
main blades move.

If you want forward flight you move the right
stick forward. That makes the front of the
swash plate move down.

The advancing flybar paddle is then tilted down
90 degrees BEFORE the main blades.

That causes the advancing main blade to start
moving toward negative pitch (and the retreating
main blade to start going positive).

Thus you get forward flight.

If the system waited until the advancing main
blade was over the nose of the heli before it put
in any pitch you'd end up going right.

Wow that's hard to explain. I hope it makes sense.

Heli's without flybars get the proper lead times with
the use of gyro's. I'm not sure what sequence of
events take place in that case.

AB

I believe input 90° prior to the output is the basis of gyroscopic procession

Well that may be....

But the control system on a heli doesn't work
by that principal although its effects are felt
by the system.

AB

wow this turned into a real complicated thread *scratches head*

Read some of this.

http://www.tpub.com/content/aviation.../14018_394.htm

Yep.... that article confirms what I was trying to say...

So, don't mess with the flybar paddles, lest ye crash.

AB

I agree =)

good explination AB =)

that's why on real heli's without flybars they have the swash linkages that are not on the 90, but they are rotated about 45 degrees. Check out helicopters on howstuffworks.com for videos and stuff on an r22 =)