Yet another question on swash plate leveling and head links length

[dude75]

Hi,

I own a TREX Sport. Yes I'm a kind of noob. Following a light crash (broken servo horn only), I set up again my head and spent again hours. I leveraged this thread https://www.helifreak.com/showthread.php?t=126947

1/ I don't own a swash plate leveling tool. Still, I don't really get its purpose as yes you can level your swash plate with but then you are not sure if the swash plate is at a correct height of the main shaft. How do you know when using a swash leveling tool that you level it as its correct position?
2/ Here is how I set up my head:
a/ After connecting all the fixed length links, I positioned all way down my swash plate, so I'm sure It's level, then I lift it up carefully and positioned it at the height that lined up the washout arm pivot points. This position is the mid travel point of the swash plate along the shaft.
b/ CP stick of my radio at 50%, I connected first the elevator link carefully without moving the swash plate and then the aileron and pitch links.
c/ Then I connected the long links, the ones between the mixing arms and the swash plate ensure I have a 0° pitch.
d/ Then used my pitch gauge to set up the pitch curve -10/0/+10 (idle up 2) and adjust again the length, at mid stick, of the long links, to ensure I have indeed 0°

This is a very very long and painful process (I'm very picky), is there better way to set up this? Manuel length where all wrong for me as I'm not using the de facto servo.
I have in order a TREX 500 ESP and would like to find a better way for it.

Thanks guys for your help.

Regards,
Hervé.

[Bob O]

Sounds like you did it right.

Regarding the swashplate leveling tool, after 2/b/ that is when you remove the head and attach the tool. You then use the tool to level the head at mid-stick, then high and low stick. Then you remove the tool, reinstall the head, and proceed with the rest of your set-up.

You don't absolutely need the tool. If your eyes are good, and you're okay with "good enough" then just eyeball the level at all three stick positions. I don't have a tool for my 600, so I leveled the swashplate by eye. The thing flies as well as any heli I've ever had.

Once you do head set-up a few times, it will go by quicker and quicker until it becomes routine.


Good luck!

[gixxum]

there are 2 swash tools. there is the one that sits on top of the swash, which also lets you level the swash at hi and low so you can make sure all your servos travel are the same. people dont realize how key this is to get a good setup. if you have 0º at 50%, thats excellent, but if you give it full positive, and put the swash tool on, 9 times out of 10 you will need to adjust the end point of one or more of the servos. same with negative. if you dont do this, when you give it full pitch doing a punch out or something, the heli will not go straight up. it will veer one way or the other.

there is also one (i use the k2) that sits under the swash. this is the one that will allow you to set the actual link length like you mentioned.


the thing is. you dont need the second.

if you measure the links per the manual (i use calipers), and properly center your servos, there is no reason to need the 2nd swash tool. once you measure the inks correctly and put the swash tool that sits ontop of the swash on, there should be very little adjustment needed. if it off by more than a turn or two, you either didnt measure right or your servos are not centered right. there arent any other variables to that.

after you get that all set, then proceed with building up the head from the swash up.

[Mr.Andersen]

Actually the leveling of the swash at low and high can allso be done bye eye.
Watch the flybarpaddle 90 degree against the heli and along the heli when mooving the collective from midle to high and midle to low.
The slightest moovement in the paddles angle is an indicator of the swash mooving out of level.
Normally the swash is level in the aileron direction but unlevel in the elevator direction.
If so make the adjustment to the endpoint of the elevator servo.
Start with aileron diection and get it level that way first and after the elevator direction.

After leveling the swash these way i often se interactin between low, mid and high stick but leav it, it will flye fine.

[dude75]

Thanks to the three of you. I really appreciated your input.
Well it seems, I just have to practice again and again until it becomes a routine.

Good point about leveling low and hi position of the swash plate, I haven't done it so far but let's say that I'm far from flying in idle up 1 and 2 mode so I should be fine, nerveless I will give a go the flybar paddle tip when I'll be building my TREX 500 that I have just received today.

Note that I have been using a precision electronic meter first (caliper? not sure about that word, pardon me I'm French....) but that didn't help, I guess it's because I'm not using the Align servos. I realized later on that in the TREX manual, you can actually just size the length using the 1:1 scale diagram of each rod, but yet in the TREX 450 Sport manual there's a bug, the long link length diagram is actually 2/3 mm longer.

Anyway, thanks. Help much appreciated. I'm going out now to draw out some Amp from my lipos with my re-tuned again TREX 450

Regards
Hervé.

[gixxum]

dont use the 1:1 method...that will end in a lot more setup because measuring it against a picture, is not accurate at all. here is what i mean by calipers (vernier calipers to be exact)

Originally Posted by dude75

Thanks to the three of you. I really appreciated your input.
Well it seems, I just have to practice again and again until it becomes a routine.

Good point about leveling low and hi position of the swash plate, I haven't done it so far but let's say that I'm far from flying in idle up 1 and 2 mode so I should be fine, nerveless I will give a go the flybar paddle tip when I'll be building my TREX 500 that I have just received today.

Note that I have been using a precision electronic meter first (caliper? not sure about that word, pardon me I'm French....) but that didn't help, I guess it's because I'm not using the Align servos. I realized later on that in the TREX manual, you can actually just size the length using the 1:1 scale diagram of each rod, but yet in the TREX 450 Sport manual there's a bug, the long link length diagram is actually 2/3 mm longer.

Anyway, thanks. Help much appreciated. I'm going out now to draw out some Amp from my lipos with my re-tuned again TREX 450

Regards
Hervé.