Couple Newbie Questions/HEAD SETUP

[jmcdonald]

I'm just finishing mechanical/tx setup on my new 550e and I have a couple questions I hope someone can answer:
1)
I have the swash level throughout its full pos. and full neg. pitch when eyeballing it and all links are sized per the manual within 0.2mm of the specs. The washout block is also level at mid-stick. My blades are at zero degrees at mid-stick. The problem is that at mid-stick, the side of the mixer arms that is attached to the short link going to the blade grips is a hair lower than the other side; 1-2 mm at most. My question is, is this a problem that can be fixed by shortening the two links that attach the upper rotating swash assembly that attach to the long side of the mixer arms, or is this normal?
2)
Prior to correcting CCPM interactions on the paddles, which is at most 1mm of movement on the trainling edge of the paddles from full neg. to full pos. pitch, I set my min, mid, and max pitch on the blades to +10/-10 and zero. Can I now correct for CCPM interactions or is it strictly vice versa? I'm confident its the other way around, but didn't have the bubble level Finless had in his CCPM 2 video. (picking one up tomorrow)
3)
In order to get the same amount of cyclic pitch in all directions, roughly 5-6 degrees, is it normal to have different % values in the swash mix menu for ail. and elev? I have pitch set to 40%, aileron to 42% for 5 degrees, and elevator set to 54% to get to 5 degrees. At 42% on elevator, same as aileron, my elevator pitch was only 3-4 degrees on the DX7.
4)
Probably covered somewhere and probably stupid question but,

Is it normal for the flybar to tend to seasaw to the same side when messing with collective stick? It slowly falls to the same side with repeated full pos. and full. neg inputs.

I apologize in advance for the long read and thank anyone who can point me in the right direction, Jesse.

[chrismechanic]

hi jmcdonald...
1. yes you can adjust those links to level it up, tbh you probly wont notice the difference so dont be too anal about it, get your self a flybar leveller and pitch guage to make setup easier...eyeballs are not very accurate.
2.not really sure what you mean, 1mm is a small amount and while hovering around and learning orientations you wont notice any difference.
3.yes the numbers will be different for different helis, no fixed values there, its something you set as you go.

yes the flybar will fall one side of the other, this is because the blades are not perfectly straight.
dont be sorry..if we dont ask, we will never know
chris

[Wolfpackin]

You might want to start with a little more than 5° cyclic pitch.

IMO the flybar 550E is slow to flip and roll, not necessarily a bad thing, but I'm running 8-9° pitch on ELE and AIL and it still flips/rolls slower than my 450 V2 that runs closer to 7° cyclic.

It's not unusual to have different values for AIL and ELE to get the same pitch, but it probably means something is not 100% level in your head setup.

YMMV

[jmcdonald]

Thanks guys. Its hard for me not be anal when it comes to this. Last night I put a

tiny bubble level on one of my flybars with some double sided tape, made sure the

bubble was in the middle with zero degree pitch in the elevator direction, and tweaked

AIL, ELE, and PITCH using small amounts of subtrim for each so the bubble would

stay in the center throughout the entire 360 degree rotation of the paddles/blades. I

tried mechanically changing the length of the swash links, but with just one rotation

on the ball links, it threw it too far out of whack. Throughout the entire 360 degree

range and with full neg. and full pos. pitch, the bubble never strays out of the

center/accross the center lines. My min and max pitch is set along with zero center

stick pitch. I think I am ready to start messing with throttle and pitch curves. Any

input is appreciated. Thanks again, Jesse

[Wolfpackin]

Level, 90°, the servo arms using subtrim.
Level the swashplate at 1/2 stick using linkage adjustment.
Level the swashplate at high and low stick to reduce CCPM interactions using endpoint adjustment, this does basically the same thing as Finless's bubble level fiasco (point is don't use subtrim for this).

[Helis4me]

+1 Wolfpackin! Follow just like Wolfpackin outlined above and you can't go wrong!
Cheers!

[texto]

Hi guys , I was reading what you were doing , and 1 thing that I see PITCH . I have always used PITCH for adjusting my total servo swing . I would go to my swash mix and with the heli turned on (using throttle hold ) put full colective on then bump up that pitch # untill the washout base just hits the top part of the head . Pitch plays with all 3 servos at once For you to level you can only play with AIL and ELE If you want to move that 3rd servo you can't at least not that way .If you wanted to bring that 3rd servo up you would have to bring the other 2 servos down instead . Oh .....your FB bone stock machine , I have the same one and this thing is rank I can not beleve how fast it can tumble through the air or do a tight loop or a fast roll or stop on a dime A 450 or 500 or a 600 is no match for this guy I use my 500 to warm up to the 550 what a difference . Both machines run a 2800 rpm head speed . and my swash mix is 63 , 63 , 70 for the pitch

[Wolfpackin]

Yes...
Once the heli is set up mechanically correct for zero pitch at 1/2 stick and equal +/- pitch at high and low stick, the Pitch value in Swash Mix increases/decreases the total pitch range and throw for all three cyclic servos. This effects the collective pitch range of the heli.

The AIL and ELE values in Swash Mix effect the pitch range (servo throw) of aileron and elevator cyclic pitch.

[jmcdonald]

What if I didn't change any endpoint adjustments to correct for CCPM interactions, but I have (down) 14 on elevator to get servo arm at 90, (right) 10 on AIL, and (left) 10 on the pitch subtrim. Now, without having messed with endpoints, the bubble never leaves middle whether it is in the AIL or ELE direction and throught the 360 rotation with full neg. and full pos. stick. Are those minute subtrim changes ok? I have next to zero CCPM interactions no matter how fast I change from full neg. to full pos. on collective. I had earlier tried changing mechanical linkage length first, but it changed too much with just one turn, the smallest change I could make. That is why I used subtrim.

[Wolfpackin]

As long as you used the subtrim to 90° the servo arms then those amounts are fine.

If you're sure that you have no CCPM interactions and the swashplate stays level throughout the collective range then you should be fine.

[jmcdonald]

Sorry guys, another question. Head setup all level, no CCPM interactions. At center stick, I have 0 degrees, full pos. and neg. I have 11 degrees, but when setting up cyclic pitch for 6 to 7 degrees, I cant get over 5 degrees to save my life. I have this problem with both ELE and AIL. Just to exaggerate, I set up elevator in swash mix to 100% ( blades parallel to bird, flybar perpendicular) and I still only get around 4-5 degrees of elevator at full forward and full back on cyclic. With 100% ELE on swash mix, the plastic ring in the swash plate is generously over the flat part of the ball that surrounds the main shaft, making me think this would have a lot of pitch, yet on around 5 degrees. Both lights on sat. and main Rx on AR6200 are on and running a DX7. Could this be a receiver batt. issue even though when setting up collective min. mid. and max., everything seems ok. It seems like I didn't have this problem the other day. Any ideas? thanks again
Also, all servos 90 degrees at center stick, swashplate level throughout full pos. and neg. throw. ???

[Wolfpackin]

I don't think you're measuring correctly.
To measure ELE cyclic pitch the blades should be perpendicular to the boom, then give full fwd/rev and measure the pitch on the blades.
For AIL, blades parallel to the boom give full L/R stick and measure the pitch of the blades.
When measuring both AIL/ELE cyclic pitch the collective stick must be at 1/2 and zero pitch.

Also, what is the Swash Mix Pitch value set at in order for you to get +/-11° collective?

[jmcdonald]

Ahhh, that makes sense. For some reason, I thought it was the other way around. Thanks a lot dude. I'm not at home now, but I'm pretty sure my swash mix pitch value is either 45 or 46%. you guys are so helpful. Much appreciated, Jesse.

[jmcdonald]

I thought that since in elevator, to go forward, the blade in the rear would have to have more of a pos. pitch than the front blade-hence why I thought that in measuring elevator the blades would have to be parallel to the boom. Is it the other way around due to gyroscopic precession?

[Wolfpackin]

I don't know the answer to that but I do know that you can "see" the ELE pitch when the blades are 90° to the boom and AIL when they are parallel with the boom.

Also, the fact that you can get 11° collective with only 45% on Pitch tells me you have enough mechanical throw of the servo's so either you were measuring incorrectly for cyclic or something else like reduced D/R must be limiting it.

[markleyland]

I laways found the bubble level to be a PITA to use as it wasn't very precise. Buy a swash leveling tool for the future and make life easy for yourself then follow these instructions http://www.truebloodengineering.com/...howpage&pid=12

[jmcdonald]

Thanks. Great info plus I have a DX7 Perfection

[NRPY]

Yeah, thanks to Wolfpackin et al for the excellent refresher on mechanical setup. It's been a while since I've done it, so I'm going to print this thread and put it in my "Setup Methods" binder.