Visual Pitch Range

[ghtracey]

OK, so all my electronics are in, and I was wanting to test fly my Titan before its 20 below here. But, my pitch guage was on back order. I set the bird up as per Raptor Technique, with servo center being in the middle of the pitch arm throw, this got me full +/- pitch at 90%ATV, which seems correct. My linkage arms are almost identical to the measurements given on Raptor technique for long arms and double-links.

Seeing as I can't measure my pitch right now, I was roughly going off of the marks on the slider (I know they are off a little when you use the 3d setup). What seems strange to me is that at full throw, the blades don't look anywhere near 10degrees, they look more like 40 or so degrees off of horizontal. Is this right, does a pitch meter not measure the actual angle?

Hopefully that made sense.

[tailStrike]

All those pitch scribes indicate is the position of the collective arm - the true blade pitch can vary quite a bit from the values indicated by the TT manual even when making every attempt to use the proper linkage lengths.

I had to adjust a couple of links in the head to correct my pitch range which was like +14/-7 to where it is now at +11/-11. I used all lengths indicated by TT and ended up w/ my pitch this far off. Only after shortening those links from like 100mm to 97mm did I get the proper range, so you absolutely cannot assume those markings correspond to any real world value until verifying with a pitch gauge.

[ghtracey]

No, I didn't assume they were correct. In fact RaptorTechinique gives them different number than the manual. LOL

I did modify my setup so that I have 0 pitch at the center of the slider's range, which came out with lengths very close to what RaptorTechnique gave. What I am wondering is that if you look at the blades side on at full pitch do they appear to be at nearly 45 degrees off of horizontal. Mine do... it seems like too much pitch. I don't have the cable for my phone with me or I would post a pic. Maybe someone could post a pic of their blade angle at full pitch for me to compare?

[tailStrike]

That sounds like a lot of pitch. As long as you are sure you have none (and preferably a couple of degrees of negative at 0 stick input) so that the heli doesn't try to lift off at near idle :D, you are probably fine to hover around until you get your pitch guage. You can always back down your pitch curve if you need to.

[ghtracey]

I managed to get a couple of pics...

Either this is right, or I botched the build somehow and managed to get WAY more throw than I should have.

[MarkD]

Whooo - that's way to much. Looks like 45deg (90deg total Throw)

You want about a 1/4 maximum of what you have there (approx 11deg each way) with the hover point at 5 - 6 degs positive pitch

You could make a rough guide by drawing a 90 angle then devide by 2 to get 45 then divied again by 2 to get 22.5deg etc which should get you in the ballpark

[Funky]

Something has to be set up incorrectly in your head to have that large of a pitch range. I can barely get +-11 degrees with the stock head. Can you post some close up shots of the head?

[ghtracey]

Something has to be set up incorrectly in your head to have that large of a pitch range. I can barely get +-11 degrees with the stock head. Can you post some close up shots of the head?

That's what I was thinking, but I'll be damned if I can tell what. I'll see what I can get and post them up today.

[ferincr]

It seems like the mixing lever are connected the other way around, otherwise I have no idea how you can get that much pitch.
The short end should go to the blades and the long to the swash.

[ghtracey]

It seems like the mixing lever are connected the other way around, otherwise I have no idea how you can get that much pitch.
The short end should go to the blades and the long to the swash.

Ferin I think you may be a genius.... I'll double check that.

Sure enough, that's what it looks like. Of course, none of the pictures I took give a decent view of the mixing arms.

[Funky]

I think your problem is with the upper mixer arms. They might be backwards or mounted the wrong way on the seesaw. Can you get a pic of the upper arms/seesaw?

[ghtracey]

Yep that's what Ferin said too Funky, before I took the pics. Somehow I got them on backwards and have the doublelinks on the long side of the mixing arm.

I wonder how many hours of redoing my collective setup this is going to cost me. :P

[ferincr]

Well, I feel great, finally I could help someone!!!!:dance

[ghtracey]

:P Thanks for the help, I was stumped. You would think that after reading this forum and every raptor site I could find I would have figured that out. Its appreciated.

[ghtracey]

Wow it goes so much farther....

I went to flip the mixing arms, but you can't the seesaw is in the way, I get to looking closer, pull the manual out and, &#^$&# I have leading edge control on the flybar. That would be where all the problems started, you can't build it any way other than wrong if you do that. Time for a teardown I guess.

[ghtracey]

Ahhhh much better now, looks like normal, and I barely even had to change my Idle1 pitch curve, 0 50 100 looks pretty damned good now. I think I can probably squeak some more throw out of it now that the blade grips aren't bottoming out.

Thanks for the help folks.

I seem to remember reading that you want your ATV on the collective to be 80% or so, is this correct? If so I will go out one hole on the collective and see what I can get for throw rather than upping my ATVs.

[ferincr]

I'm sure somebody did (or will) suggest this but get you heli checked by somebody experienced before you fire it up. Just to keep you and your investment safe.

[ghtracey]

LMAO!!!! (check the HF Locator)

I know two people who fly helis here, myself and my friend. Of the two of us, I'm the one with experience. I asked at the field here, supposedly there *may* be a couple of others in the territory that fly helis. That might explain why I bought the sim last year, the heli in March, and I'm just getting ready to fire it up now. I've researched everything I possibly can online to make sure that I've built them (my friend's also) right. I actually did the complete setup with my tx in realflight, throttle and pitch curves, throttle hold, cyclic:throttle mixing, the works to make sure I had a good handle on things.

I know of a couple of people that have heli experience, one is the old gentleman that helped me trim my airplane, but I really don't feel confident taking advice from someone who doesn't own and fly a chopper currently, so I ask here. Its the best I can do, now its all in fate's hands. LOL

[ferincr]

LMAO!!!! (check the HF Locator)supposedly there *may* be a couple of others in the territory that fly helis...
... so I ask here. Its the best I can do, now its all in fate's hands. LOL
Welcome to the club, I'm in the same boat. Just don't do anything that you are not 100% sure you understand the "cause & effect" and do a lot of reading and comparing info (you'll be amazed at all the different points of view for the same subject).

[vandelescrow]

Seen as how you don't have anyone you can turn to in your local area, I would recomend using training gear. They are not only for learning to fly but also to make sure you have everything set up right. like servos reversed or gyro reversed.

[ghtracey]

Yes, I was planning on tossing some uglysticks under it (not the airplane variety of course:P) Then I'll hide in the woods and fly it until I can take them off and come back out in public. LOL I was pretty carefull with the setup though, especially in the tail, I definately wanted to avoid the first power up ending in a piro of death. So... unless there is something completely funky, like the swashplate not tilting in the direction the helicopter would move, then I shouldn't have reversing issues. I'm more inclined to use the gear to stop me from tipping it on the ground if I come down with a little too much sideways speed.

Hopefully on my Monday I can post a first hover thread.... that was months in the making.

[vandelescrow]

I know you have done alot of research so you probably already know this but just in case.

Even thoe the tail servo moves the right direction when you give it input, the gyro may still be reversed. How you test this on the bench is: give it right rudder, look and see if the servo horm pulls the rod to the front of the heli or pushes it to the back. Now center the stick and jerk the nose of the heli to the left (fast). The servo should move the same direction as when you gave it right rudder. If not the gyro is reversed. It is easy to get this wrong because the servo moves vary quick one way, then back the other. The first direction it moves is what your looking for.

Don't worry about using the ugly sticks. We all started there, well atleast the ones that had enough sense not to waste all the time and money it took to get the bird airworthy. In fact, I'm currently putting together a new heli and even thoe I know how to fly, it is going on the ugly sticks for its maiden voyage.

Another thing about the ugly sticks. They will through off the center of gravity on your heli, so if it does not hover with hands off the right stick, put in some trim / sub trim. Don't bother adjusting linkages (other than fixing tracking isues) till you can hover with out them.

When you are ready for that step. Hover with the nose into the wind high enough so you are not getting any ground effect, let go of the right stick and see which way it drifts and how fast. Then do the same with the tail into the wind. Compare the two and adjust acordingly. This is the only way (other than fly in absolutely no wind) to see if the heli needs adjusting or it's the wind.

You will want to get your heli as close to hover with no right stick input as you can, with as little trim / sub trim in your transmiter as possible . The reason for this is if you fix the problem using your transmiter, when you get to the point where you are inverted, the problem will be twice as bad in the oposite direction.

BTW: Good luck

[ferincr]

Don't worry about using the ugly sticks. We all started there.
BTW: Good luck
Tell me about it,
I couldn't get wiffle balls (or what ever their name is) so I used toilet buoys for them:YeaBaby::YeaBaby::YeaBaby::YeaBaby:

[Funky]

:lolol That is great!!!

[ferincr]

:lolol That is great!!!Oh yeah and I forgot to mention with the grooves on the ball it gets a really good grip on tight turns too:rolling:rolling:rolling