Hi.
Ive read loads of threads on servo alignment but not 100% sure if you make the servos 90degrees with the servo arm to the case of the servo or if you make it 90 degrees to the push rod that leads to the swash plate with the screew at the centre of the servo.
Thanks for clarifying this for me.

Actually it's the screw as this is the pivot point for the servo. Also 90 degrees to the swashplate if looking at it level. Servo should be straight across horizontally and pushrod should be directly veritical and swash perfectly horizontal and level.


DY

thank you[sm=thumbs_up.gif]

I saw a cool way to level your swash on youtube. You use an allen wrench.

Remove the head above the swash. Twist or cable tie an allen wrench upside down or 90 degree at bottom, to the main shaft. Now twist the wrench around the shaft is the swash the same at all points around the shaft? if no alter until the allen wrench is exactly the same at all spots. MAKE SURE to do this with esc on, motor disco'ed, idle up on and center left sitck, and swashplate should not hit the base if you do full downward motion on stick. You will notice some binding on the collar if you have it too low.

Once the swash is level then you can work on leveling everything else.

DY

By the way it's way worth it to do this yourself and not rely on anyone or anything else. You'll learn so much more this way.

DY

A swashplate leveling tool, or the allen wrench idea, is worth its weight in gold.
The last few times I used one to level my swash at low, half and full stick I didn't need any trim for the heli to fly perfectly.
And I'm still running that way, with zero trim on cyclic.

This is the tool I use:[link=http://www.readyheli.com/T_Rex_Swashplate_Leveler_p/leveler.htm]Trueblood Engineering[/link]

And the bench users guide within that page is the absolute best, most clear and concise, description of what needs to be done to get a perfect swashplate setup.

I highly recommend reading it even if you don't intend on getting the tool.

Thanks wolfpackin for the links. I have got one of thoses I had it imported to the uk as I could not find any leveling tools at the time.
So far I have leveled servos 90degrees,+ swash. I am waiting for parts to be delivered tomorrow to complete my setup.
It is level throught the range and as it is a stock built heli from eflite I am hoping everything still perfect center of gravity and she will fly perfect.
This is the first major repair that I have done, I have all the recomended tools, so I am hoping I have used them correctly and she flies like an angel.
will post back once ive completed the rebuild.
Thank you for your suggestion and help. Couldnt do it without you guys[sm=teeth_smile.gif]

Yeah I can let her go for 2-3 seconds before I have to do any (at that point major movements).


I do see many people recommend that you remove the springs from both sides of your transmitter(except rudder channel). There really is no centering on a heli, you're always going to be moving both sticks.

Personally I have my springs in still, some people swear by removing the elevator and aileron springs. I have it trimmed well enough that center is pretty centered. I do constantly have to battle the spring to maintain, I've thought many times about removing.


Anyone else have thoughts on that?

DY

I am wondering if the Trueblood will work on a CP Pro I just ordered one. I am thinking it might be too loose on the shaft but I will give it a shot since I will be getting a B400 in a month or two anyway. Mabey I can rig something to make it tight on the shaft with a washer or something.
Carl

I still use all my springs too. I loosened the screws so my hands don't get tired flying. There is just a little resistance. I might be the odd man out, but I like fighting the springs a little. I learned my stick orientations by knowing were I should feel resistance to do a manuever.

Nick

I have the bits that I was waiting for and I have put them on. (seesaw holder)
Everything is level.
The problem I now have is sorting out the pitch. I spent all evening trying to do it, but I just can understand it.
At the moment my red blade (tipped for tracking) is +13 full, -0 centre and -5 at no stick.
The blue blade is +13full, 0 at centre and -3 at no stick.
I adjusted the red blade and the reading is +11 full,-2 centre and -7 no stick.
I seem to be turning in the right direction, but just cant get both sides to be anywhere near the same or what they should be. (+10, 0, -10)

The pushrod that I adjust is the same as the tracking so now my tracking is way out.
Please could anyone tell me where I'm going wrong.
Many thanks

Are you checking these pitches with the motor unplugged and the heli in idle up mode?
If not you need to do that or change the Throttle Hold curve to 0-25-50-75-100.

Next thing is to make sure at half stick the swashplate, washout base arms, flybar control frame arms, blade grips and mixer arms are all level and parallel with each other. Otherwise you will never get linear movement and consistancy in regard to pitch.

I'll see if I can get SeaComms to jump in on this but let me know if you got that far.

Hello.
I am trying to set it up on a DX7 that has the settings below.

motor is disconected but I was in thottle hold and not idle up. Everything is level apart from the blade grips, but that may be because of the pitch curve. I do not really understand pitch / thottle curve so I just put in the settings Casey Lamm suggested to use with the DX7.
http://www.rcuniverse.com/forum/m_7464466/tm.htm

I will try doing it with my DX6i and see what happens there.
Thank you for your help.


Throttle Curve -EXP OFF
Norm L - 0.0, P1 - INH, P2 - 50%, P3 - INH, H - 100%
ST-1 L - 100%, P1 - 92.5%, P2 - 85%, P3 - 92.5%, H - 100%
ST-2 L - 100%, P1 - 92.5%, P2 - 85%, P3 - 92.5%, H - 100%

Pitch Curve - EXP OFF
Norm L - 35%, P1 - 42.5%, P2 - 50%, P3 - 75.0%, H - 100%
ST-1 L - 0%, P1 - INH, P2 - 50%, P3 - INH, H - 100%
ST-2 L - 0%, P1 - INH, P2 - 50%, P3 - INH, H - 100%
Hold L - 35%, P1 - 42.5%, P2 - 50%, P3 - 75.0%, H - 100%

Throttle curve is just the amount of power you have at different points.


0 being no throttle, 2 being up some on left stick. 3 being midstick. Just a one to one. This is for regular. For idle up throttle is always on there is no low point. Mid (so 3) should be about 75-80 percent power then each end point should be full power so it's a big V.


Pitch on the other hand is just the blades. It should pretty much always be the same but using idle up gives you the most correct settings.

The idea is at point 3 (mid left stick) the blades should be level and 75-90 percent power or not doing anything but spinning the blades. then at low point the blade pitch should be at full neg pitch whatever you have that set for but usu between 10-12. At point 5(high left stick) you should have most positive stick or 10-12 meaning with throttle curve you have full power and full pitch.

On normal the pitch is 0-100 is in various configs some people like 45(being just negative).65(neutral)..(half positive)75.(mostly positive)88.(full positive)100 or some combo of such.

Meaning at low stick and normal throttle the power is off and no pitch or some negative pitch for those who want it more correct., at mid stick you have mid power and medium pitch and at high stick you have full power and full pos pitch.

That's all that means

so

throttle on idle up is big V
Pitch is a straight line 50 being "neutral" 0 being full neg and 100 being full pos.

Throttle on Reg mode should be a straight line from 0-100 or some combination
Pitch should be starting at 45 or so and going to 100 in a curved pattern

Correct me if I'm wrong guys just doing it from memory.

DY

Phill,

Those curves look fine.

My main point was if you are measuring pitch with throttle hold on then you will be getting the pitch for that curve.
In otherwords Throttle Hold has it's own pitch curve.

So, in the examples you posted above if you are switched to Idle up with Throttle Hold on you should actually get -3/0/+10 for
pitch at low, half and full stick instead of -10/0/+10.

Does that make sense?

Thanks Wolfpackin, yes that does make sence, and so does your post DrunkYoda. Thanks[sm=teeth_smile.gif]
Today I spent another 4 hours trying to get it to be -10, 0, +10 . I did it with the DX6i, totally started from scratch, which Im glad I did because it helpped me understand it more. I am still not getting even numbers on both blades though.
I have managed to get one blade at half stick -1 and the other -2. full stick +9 and +10 and at at low -4 and -6.
Is it ok to fly like that or must you have them both the same?

I am wondering If I have damaged the flybar control frame set as I cannot get them to both be the same . It looks ok .
Another odd thing that I noticed. I spun her up just to see what the blade tracking was like. at low to mid it was slightly out. Mid it was spot on but a few clicks more and it was out of line. Does this mean anything ? I have never noticed this before but I have never really paid that much attention to it before.
Thank you for your continued help I really Appreciate it.

You're getting closer.

What I said above is very important or you'll never get equal pitch on both blades throughout the collective range.


Maybe this will help, it gets good about 2 minutes in.

[link=http://www.youtube.com/watch?v=hS7L-bapzRQ]Sokal Video[/link]

Also you may need to move the swash up or down a bit and re-level Everything to make it 50/50 It's a little game of level mid swash mid stick equal pitch.

DY

PS What I mean is the control arms to swash may be too short or too long and may need to be adjusted a bit whichever way is wrong, if too much low then you need to move up if too much high you need to screw them in a bit.

Hey Phill, just looking over this and it seems like you are on the right track, but maybe through fiddling you have the links to the swash at the wrong length affecting everything from there up.

Time to start again me thinks. Navy blade on RC groups has been going through the similar problems and through some help form others got all the default factory link lengths. He has done a pic with the lengths on it they may help you out.

Start by setting all servos to mid alignment to their cases using subtrim, with pitch at 50% and all normal trims to 0, dual rates, expo etc all to stock default settings. Use a pitch curve of "stunt mode" with a little mod on the middle 3 points (ie, on a 5 point curve like the dx6i set the pitch curve to 0, 50, 50, 50, 100; center stick is not so critical then but you still have full throw top and bottom).

The swash to frame measurement is with the pitch at mid stick (50%).

This should be an excellent starting point, then you should be able to just adjust the links to the blades to fine tune 0 pitch at centre stick.

I thought that's what I said, do you have link to the control arms length picts, that would be cool. May help everyone out.

DY

Yep, exactly what you said!! Just was lucky enough to find a pic with all the stock measurements.
What did you mean Yoda? I thought that pic had all the links and their lengths in it? or...... is the pic not showing to everyone else? If not let me know and I will try to attach it.

Nope I don't have a link or pict.

DY

Hi Everyone, thanks again for your help.
SeaComms I cant see your link or pic either.

Im going to start again on my DX7 as that is the TX that I want to use. I will set everything to 0 or what the setup should be and see how I go.
First I will be watching Sokal's videos [sm=teeth_smile.gif]
Let you know how I get on.

The problem is not in the transmitter is what we're trying to tell you. It's in the physical setup of the control arms to the swashplate from your servos. These regulate through swash mixing on your controller the pitch. But you have to start with the swash in exact center to get exactly the same amount of mix to make the blades go +-10. For example if you have the swash too low you will never get to +10 no matter what you do because of the physical limitation of the servo/swash it can't go any higher. The controller doesn't have anything to do with the physical disability the swash has, to go high enough to get to +10. Likewise for too high to start.


Start with perfect swash/servo placement let me see if I can find the video to explain.

Watch these videos:

http://www.helifreak.com/showthread.php?t=11373 (you may need to create a new id to use the site then go to this link.)

Particularly CCPM 1 and 2 and pitch/throttle curve setup. This will give you the exact fix for your issue.

DY

Bugger...... that would explain the comments! let me try to add as an attachment..