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View Full Version : Almost ready to quit. Please help.


keith7537
03-11-2009, 01:10 AM
This is my second post. My first one everyone was very helpful and I need some more help because I am very frustrated. I am getting tired of replacing blades. I have about 30 sec. of flight time total and trashed three sets of blades.
First I will start with what I have done to the helo. I put in the esky 3900 BL motor and a 30a esc I can't recall the brand right now. I upgraded to the 43t tail pulley and for my last flight I was using my new DX6i Tx.
I have watched all of the 101 videos so I thought I could get it set up to hover since I'm able to hover pretty well on the Clearview simulator. I used the sub trim to level all the servos, used the swashplate lever to check that. Balanced the blades and checked the pitch which was at 9 degrees both directions. I had the Tx set up to the values that are on the PDF on ushobbysupply. I figured with the expo up and the servo throw down a little it would be a little tamer to fly. I don't have a HH gyro on it yet but it is in the mail.
When I lifted off the heli tilted left. I tried to correct it and it traveled in a large circle. I got it to stop at tail in but it was still tilted left and no amount of right stick would move it back. So it crashed and destroyed my third set of blades. Luckily the only other thing I had to replace was the tail boom. I stripped the heli down to check everything just to be safe though. The only thing I didn't do prior to flying was use the level to check CCPM interaction like on the videos. I figured if people can fly with a stock Tx without doing it I should at least be able to hover, and I don't have a bubble level.
So as I was trying to set it back up I totally reset the Tx to start from scratch. I got all of the servos traveling in the correct direction and used sub trim to do the final leveling on them. Got the swashplate level at mid stick as I did before but the figured I would try to do the CCPM stuff too. I moved the swash all the way up and the left rear servo arm was higher than the others. In the video finless says to use travel adjustmen to try to fine tune it. When I moved the travel adjustment the servo doesn't change position at all. I tried it on all of the other servos too and nothing.
After that not working I reset everything so the swash was level at mid stick and went to the monitor screen. I noticed when I increase throttle/pitch the aileron goes left, and that is what caused me to crash is it tilting left and not being able to correct it. The elevator also went slightly down. Are they supposed to move like this when I increase throttle and if not how do I fix it. Also if my travel adjustments aren't moving the servos how am I supposed to fine tune it.
I did check about the recall and I do have one of the date codes that were in question. The website has a check to see if it needs to be fixed and my Tx is working like it should so I don't know what to do. I have one of the HK 450 kits comming because I wanted to try something larger and more stable but I want to fly my king too. Plus I don't want the same thing happening with my new heli tilting left and crashing.
Please help. I need advice.

Mglass
03-11-2009, 06:10 PM
Not sure if I can help, but I can try right? Anyways

1. When looking at the monitor on your DX does the AIL, ELE and AUX(If you have pit in AUX) move when you throttle up? They may move in different directions if you have certain ones reversed or not.

2. When you have the throttle centered and flip the idle up switch, does the swash stay level all the way up and down when you go positive/negative?

3. What does the settings look like on the D/R&EXPO screen? Mine are 0s first column, 100% second, then +10%(whatever expo you want)

If need be I can give you all my settings off of my 6i, I don't think anything would change between your bird and mine.

LEONARD ANDERS
03-11-2009, 07:43 PM
Okay lets start from scratch, un hook all servos from swash plate ,now turn on tx and rx UNPLUG MOTOR when you move sticks one at a time does each servo do what it supposed to example when you move throttle from idle to half stick does the pitch servo move half way up and then full stick,do the same with all servos my hbk2 has had just about every esky part fail with exception of 2 servos but when my pitch servo decided to go bad it just didnt quit it would move just enough to make me think it worked until i singled it out i will be happy to help you as much as i can just use my pm for further questions but lets start with all settings back to factory most txs have a feature to clear out old settings and start over it might take a little while but dont get get down lets get verticle

:clappp

DumbDawg
03-12-2009, 11:18 AM
If you have one of the Tx's that are on the recall... SEND IT BACK regardless of whether you think its working good or not... The pots are faulty and will fail over time... Its best to get them changed now... FOR FREE... rather than wait and possible have to pay for it later....

Once you've gotten ur Tx back then we can help sort this out... Its not a big deal... DON'T use ushobby's settings... Also... do you have training gear on ur heli??? If not... put it on... It will save you some money in the long run...

happy heli'ns

keith7537
03-12-2009, 01:08 PM
Thanks for the replys. After I posted the original I went back and started from scratch again. I reset the Tx and took the heli apart. I checked the servos and they worked fine but some two of them were a ways off from 90 degrees. So while the tx was on at half stick I repositioned the servos. Then put them back on and used sub trim to get them as close to perfect as I could. I leveled the swash plate and for some reason this time it was good in all positions (up, down, center). I think the Tx is supposed to have the other values move when controlling throttle. If not it isn't affecting the servo movement now.
I was using the traing gear when I crashed but it got too high and tilted sideways and I couldn't recover it. I pretty much assumed the Tx will go bad soon and do plan on sending it in before something happens just to be safe.
My question now is I am trying to follow RADD's and I have a ? about the tail. I am doing it on a large piece of cardboard because that is the only flat surface I can use at the moment. On the first battery he says that the tail should move left. I know it does as throttle is increased because of the torque from the main blades. I am trying to set the tail up perfect and I want to know if it is supposed to move if the throttle is held in one position or stay stationary. I think if it moves then when I fly it will move but it could also move from the ground affect. I just need some advice on this. I don't plan on trying to fly again until I get my HH gyro. I think that might help with some of my problems. Again thanks everyone for all the help.

DumbDawg
03-13-2009, 09:41 PM
The tail and heli is all set up in rate mode on the gyro....

You can even unplug the gyro if you like in order to set the tail servo on the boom correctly... The tail shouldn't go anywhere unless you give it stick input... otherwise it should stay steady... To get it there you need to move it along the boom until you find the sweet spot... So move it back or forward until you get it to the point where the tail stays solid in spot... when you get close you'll have to move it in very tiny tiny movements... millimeters...

When you do go to buy another gyro, head hold, do NOT buy the ESky head hold gyro... they are very poor quality gyro's... The Telebee(ATV) gyro or the G401B gyro from cnchelicopter are the best choices...

hope this helps

happy fly'n

supra6
03-14-2009, 04:22 PM
Well when trying to get the tail correct be prepaired for a bit of frustration, what may help is a lazy suzan, I got one at a kitchen store, heavy wood for about $10. Many people don't like this idea but when you are first learning I think it helps. Anyway the idea is the have the proper anount of pitch, to the left, on the tail to counter act the main rotor rotation.
You can do this with your current gyro, set the rudder to the mid stick position, check to see the servo arm is as close to 90 mounted on the servo as possible, if you have any other spare servo arms try them as the spindles may line up different, do not use trim or subtrim to get 90 just as close as possible with the positioning of the arm on the servo. Check servo rotation, rudder stick left needs to pull the tail right so the pitch slider on the tail shaft needs to go to the right servo arm will move reward to do this.
Ok all is well so far mount the servo on the boom, with the rudder control in neutral connect the control rod between the servo arm and the control arm and position the servo along the length of the boom to obtain mid position of the slider on the tail shaft, this should give about 0 degrees pitch make a mark on the boom next to the servo mount for reference and slide the servo forward about 2mm. Tighten everything up tape the heli to the lazy susan and spool her up. You should be able to get to around 70-80% collective and not be in the air so see what the tail dose. Keep in mind that as you spool up the tail will move around, you do not have sufficent tail rotor speed yet to yeild the required sideways thrust to counter the main blades and also there is no friction on the skids to prevent rotation. After she is spooled up you'll see how you tail is acting and you then move the servo length wise along the boom to compensate for what you see. Stable at 70% collective and tail rotates (yaws) left means you have to much pitch to the left move the servo back slightly, using you reff mark. These adjustment are small take you time and see how close you can get it to holding with NO stick, trim or subtrim (if your TX has this option).
Ok things should be getting better, as you say you have a RATE gyro now so the difference with HHgyro is that RATE just trys to stop the unwanted rotation and HH gyro will try to return the tail to the position it was in before displacement. This is a way of getting things close before a flight after you have done a rebuild ou such, when you go to fly it will be a little off but then it's the same thing SMALL movements of the servo to find that sweet spot. Welcome to the world of gyro, look forward to alot more head pounding and gray hairs before your done.

DumbDawg
03-15-2009, 11:34 AM
Just thought I'd toss in another point here... You don't want to use subtrim at all... Reason is when you get a HH gyro using subtrim will actually confuse the gyro and you'll have a smeg of a time getting the heli to fly right... You are aiming for that spot where the tail stays put... or even if it has a very small tail creep that can be corrected with one or two clicks of trim is ok...

But if you can correct it with a significant amount of trim then its to much and you'll need to move the servo... Like supra says... paying attention to the direction the tail moves so you can move the servo in the right direction for correction. Remeber... at this point it will be very small movements... frustrating at times but you'll get it...

happy fly'n

supra6
03-15-2009, 06:45 PM
So why then use subtrim, you may ask? It's for the setup , to get the 3 collective servo's 90 degrees to teh case, the servo arms.
Also some people use it on the tail AFTER the maeh setup is correct to correct for a slight drift (yaw) in HH mode.

keith7537
03-15-2009, 07:17 PM
Thanks for all the replies. That answers my questions perfectly. Now I have to go mess with the tail servo some more. I was going to why use sub trim at all but I get it. The tail I just want as close to 90 as I can without it and then move the servo to set up the tail. Thanks a lot.
Keith

DumbDawg
03-15-2009, 07:37 PM
I should clarify what I mean then... subtrim is fine for getting the servo horns to 90 degrees... But once set up you shouldn't actually use subtrim to make final adjustments to counter the yaw... This is what tends to 'confuse' the gyro some...

A better way is to shorten the front right servo linkage by one turn... This puts the swash into a front lean so when the heli lifts off it won't yaw to the left as is normally the characteristic...

hope this makes what I said a little clearer...

happy fly'n

Magenta
03-15-2009, 10:40 PM
Just thought I'd toss in another point here... You don't want to use subtrim at all... Reason is when you get a HH gyro using subtrim will actually confuse the gyro and you'll have a smeg of a time getting the heli to fly right... You are aiming for that spot where the tail stays put... or even if it has a very small tail creep that can be corrected with one or two clicks of trim is ok...

But if you can correct it with a significant amount of trim then its to much and you'll need to move the servo... Like supra says... paying attention to the direction the tail moves so you can move the servo in the right direction for correction. Remeber... at this point it will be very small movements... frustrating at times but you'll get it...

happy fly'n
Why does subtrim confuse the gyro and trim doesn't?

DumbDawg
03-16-2009, 11:03 AM
My understanding of it follows, repeating what I've been told and it makes sense to me and does seem to work...

You center the servo arms with sub-trim which is like putting in a mechanical centering point on the servo itself... Almost the same thing as physically moving the horn on the gear, except its being done internally with electronics. Once you have everything leveled off with sub-trim which is what its for then you shouldn't have to use sub-trims to correct any issues or slight issues, using trims only after...

But back to why's... The gyro wants to correct flight deviations and when you input subtrims for corrections you are changing flight correctors that the gyro has a harder time correcting... Trims don't change mechanical setup only gives electric signals telling the gyro to limit or add to its corrections for the desired changes... Its a tough one to explain but that the gist of what I've been told by more than a few people...

I'd certainly like to hear from someone who knows more to maybe explain it better or to refute and offer a counter explaination... Hope this helps some...

All I know is that when I use subtrim to level out the swash then leave it alone. And I finish the head leveling according to what Finless says then my heli's fly a lot better. If I need to correct flight characteristics then using one or two clicks of trim is all I should need... Any more than that and I should really be sorting out mechanically where the heli needs to be adjusted to correct this... I try to stick to what Finless says in his vids as heli's are all about setup if you want a good flying heli...

But like stated before if you want the heli to lift off without yawing to the left then simply put a half or complete turn on the left front servo linkage. This drops the swash a bit on the front left and counters the natural tendency to yaw left when lifting off... I've done this on the K2 and it works... Haven't done it on the bigger heli's tho but I'm sure it will work there too...

Does this help??? There is more to this than what I've explained, this is the readers digest version... lol

happy fly'n

supra6
03-16-2009, 04:50 PM
Sorry DD yawing implies nose left or right movement (along the vertical axis, we tend to use the term drift although I believe yaw would be more correct different story),Magenta the heli moving to the left on take-off completely normal and one turn in on the right side servo should hepl but the debate is still ongoing about this pratice. If the amount of left movement can not be controled with right cyclic on take-off then there is something wrong in the swash, seems most people go with a level swash and as you lift off apply right cyclic untill in the air out of ground effect. Also remember in a hove there will be a slight bank angla to the right when you are stationary.

DumbDawg
03-17-2009, 11:09 AM
My bad... brain not entirely engaged...

But I agree with the swash correction and the debate around it... Meaning starting with a level swash or putting in a turn or two into the right front servo... Think I mentioned that already... I 've done this on the K2 but not the 450's... It does work but as the debate rages on whether its a good practice or not...

Argument is, for those not aware, that the linkage shortening route doesn't teach you to compensate the tendency the heli's lifting off to the left and correcting with right stick movement... Personally, IMO, it doesn't matter which route you go so long as ur having fun flying and anything you do on the K2 to make it easier to fly is perfectly OK... If ur a purist then obviously you'll want to level swash and fly with thumb corrections all the way... no cheating... :)

Thats my take on things...

happy fly'n