HELP!!! Tail setup problems

[dsmit258]

In setting up my 700 tail, I seem to have a problem with pushrod length. I setup the servo arm and intermediate bellcrank (at the back of the frame) at 90 degrees, and the tail pushrod to the book value. It seems like the pushrod is just too short to get the tail blades at zero degrees. At first I thought I did not have the tailboom seated all the way, but have rechecked that several times and it appears fully seated.

Anyone else have any problems like this?

[Mercuriell]

Just get the servo arm, cranks front and rear square - the blades shouldn't then be zero degrees but about 8° right rudder - this approximates to flight neutral position.

[erniefritz]

Just get the servo arm, cranks front and rear square - the blades shouldn't then be zero degrees but about 8° right rudder - this approximates to flight neutral position.

+1 , Mercuriell is correct , the tail servo and bellcrank should be 90 degrees and the tail blades should be set for neutral hover.

[scooby61]

i've been taught that center was center, whats with the 8 deg. right rudder? is this true on all heli's? i've always set mine up straight down the line 90deg servo 90deg bellcrank tail blades 0 pitch.

[erniefritz]

i've been taught that center was center, whats with the 8 deg. right rudder? is this true on all heli's? i've always set mine up straight down the line 90deg servo 90deg bellcrank tail blades 0 pitch.

i've tried both way's (0 pitch and mechanical center) and all gyro's from spartan to 401 to 611 all worked better and held the tail more consistent when set up with a neutral mechanical hover...

.what this means is you have the machine set up with 90 on the servo and bell crank ,and the blades are set to approx 8 deg right to compensate for the torque of the main rotor while hovering.
to test if you have it centered correctly , you bring it up in a hover and switch your heading hold off to rate mode and see which way it drifts , when the drift is gone your centered mechanically .

when you set your blades to zero with the servo and bell crank at 90 deg , the gyro has to compensate for the torque as soon as the heli leaves the ground, which means that the servo is no longer 90 deg at hover. this is why some get a different piro rate for left and right piro's. the Arc of the servo is different for left and right because it's not centered at a hover. Also this is why higher end gyro's have a different left and right endpoint adjustment. and lower end has a single servo limit pot that you adjust to the side that needs the most throw.

A Heli should be able to fly in both Rate and Heading hold modes on the gyro when set up correctly and the only way to do that is to set it up with a neutral hover.

Yes it will work also with the blades set to zero , but then the servo isn't centered during hover and the center Neutral point of the servo is not center to the gyro... just my 2 Cents.... :)

[scooby61]

ok then i'll try that and see if i like it better thanks for the clarification, one more question though will this reduce the the tails tendancy to tourque out while spooling up on the ground?

[Mercuriell]

ok then i'll try that and see if i like it better thanks for the clarification, one more question though will this reduce the the tails tendancy to tourque out while spooling up on the ground?

Align helis are designed (unlike the Raptors) so that when the slider is mechanically centre (and the cranks square) then the necessary 8° offset is built in. In theory and common practice HH gyros don't seem to need this as much as the old rate gyros but I agree with erniefritz that they do seem to work better if set up in this way. This also gives equal travel and limits for R and L rudder.

[sonofcar]

I run the the solid g and there is no rate mode only headhold(love it). In the set up vids for the gyro he says go ahead and center the pitch slider. On the 700 is pretty much 0 degrees with slider centered. Thats how i do it, but could be different for your gyro.

O and the guy in the set up vid is curtis youngblood, so if he says center it I am going to. Of all people he would know his gyro and heli setup.