Raptor Dance!!

[ibflyen]

I have just put together a Titan 50 and went to try and hover it today and when it got just to the point where it was getting light on the skids it started to dance from side to side pretty violently.
I had balanced the blades and have compared the pitch between both blades and all seems fine there.

I thought maybe the head speed was too slow so i changed the pitch curve slightly but still have the same problem.I set up the heli from the manual as far as pitch and throttle curves go and the same with the mechanical part but the manual is a bit lacking in instructions.
Is there a video that shows how to setup all the linkages and curves?

Any suggestions and ideas would be greatly appreciated!
Thanx

[DebianDog]

How tight were the blades ;)

You should be able to move them fairly easily in the grips back and forth but they should still be tight enough to not fold up when you pick the helicopter up and turn it sideways.

[ibflyen]

I just checked them and they take very little pressure to move and they will fold up by themselves when held on its side.
I have never had a nitro Heli before.
I fly a 450 Trex not real well but into forward flight without any 3D yet.
I got a good deal from my LHS on the Titan because he wants one in the air but i failed to get it today because of the ugly dance it was doing right before liftoff that had me a bit scared!!
I figured i would do some research on the net to find out a good setup that seems to be working and see if anyone has an idea what my problem is

Is there a build and setup video for the Titan like there is for the Trex somewhere?

[stevejr72]

This website will tell you everything you need to know...
http://www.raptortechnique.com/

[DebianDog]

Only because it happened to me.

Are you sure all the blades and paddles are facing the right way?

Even if the linkages were wrong if you are 0 pitch center stick and have the same amount of negative at bottom stick then you should not have a "violent shake"

[Venzent]

I've the same problem with a Raptor50v2.....It seems to be no problem....It only happens at a certain headspeed/pitch...Just push it quickly beyond the critical point....

[BigEdge]

Make sure your flybar is centered and the paddles are equal distance from the head.

I experienced the same issue after a rebuild.
Pulled my padddles and measured each side of the flybars distance from the head... Flybar was 2mm off.
I Re-Centered the flybar. Then, after re-attaching the paddles, made sure they were also equal distance from the head.

[TooBizzy]

I have a Raptor 30 V2.....Am just learning to hover as well. On my first attempt, mine got the shakes really bad too. Thought it was the blades out of balance since it has set since Christmas....Been flying my T-Rex and admiring the Raptor setting on the coffee table! Don't know how I've slid that one past the wife so long, but it did look good setting there!. Any how, it wasn't the blades....I took them off and rebalanced them. They were still perfect. It turned out to be my curves....Too high of head speed....Go to http://www.raptortechnique.com for all your answers....My new curves for normal are as such....

Throttle
Normal 21, 32, 40, 48, 100

Pitch
Normal 43, 54, 65, 76, 86

I have idle 1 and 2 set up, but am not there yet....These curves are much different than what I had originally...They did the trick, no more wobble and it hovers nicely at these settings...It gets light on the skids at about 1650 rpm....All I have is a digital tach, so it doesn't sound lke a good idea to me to check it while the heli is in the air :-) 1650 is very close...I don't know how close these will be for a 50. You still might check raptortechnique....Hope this helps...

jb

[xrbcoronalogoflyer]

after converting a 30v2 to 50v2, i developed the 'dance'...it came on just before lift-off, and while lowering the collective after landing...the worst occurrence was after popping up to 50-feet...the blades were extremely out of track (2-3-inches)...it looked like one of the links came loose, and it was about to crash...but i managed to land, spooled up again normally (but didn't take-off)...i lowered the headspeed, recalibrated throttle and pitch curves, checked flybar, greased the spindle, flap dampers, and thrust bearings, loosened the blade grips a little, reviewed raptortechnique--basically followed everybody's advice above...problem solved...i think the main problem was binding spindle and blade grips over-tightened...thanks everybody...ken

[ptautor]

I have just finished building my first heli. TT Raptor 30 V2. I have an OS .32 engine with a tuned pipe. I have run a tank through just breaking the engine in, without lift off. Im wanting to prepare to take off, and want to set up the throttle. What rpm do i need to set for each of the throttle curve positions? Can someone help me with this? Thanks

[vandelescrow]

ptautor

You really should have started a new thread for this.

For starting set your throttle curve to be linear (point 1 = 0, all points in between inhibited, Last point = 100). Then adjust from there as needed.