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sly the dogman
07-20-2009, 09:04 PM
Heli "fell" from a couple of feet on wet and soft ground, pinion
separated from main gear. Great difficulty tracking blades
turn the link 1/2 way and the blade above lands underneath the
lower blade and this goes on either way, cannot track them !!!
When the head is spinning there is no wooble, everything seems
right, the paddles are horizontal and straight.
Bent feathering shaft ?? (no apparent signs)
Any ideas ?
Hey thanks :dance

supra6
07-21-2009, 04:36 AM
If heli-feli from any height, the main and feather shafts are most likely bent, to see it you really need to roll them on a glass surface.
Now if they are straight then take a good look at the washout block and arms, snug but moving FREELY, Look real close at the oval links to the blades, small cracks are hard to see.
Next Blades can crack but not rip the shrink wrap coating, also the stock blades are prone to warping.
Of course make sure you have full an unfettered servo movement, some of the gearing could be stripped at the extremes of travel. Did you setup the head after the crash?
Sorry I just reread your post, if the pinion was loose I suspect the main has to be bent, also the main gear is not danaged, they can crack on the center hub tough to see.

sly the dogman
07-21-2009, 12:02 PM
Hey,
what is an "unfettered servo movement".
The heli is straped down, I spool it up and all servos work as they should.
Did I set up the head after the "drop" ? The top ring-like pushrods were off
both sides and on one side the rotor head control arm was off, that's all.
Well that's enough.
The pinion moved (vibrations) because of washers that were directly underneath the
motor to give the pinion the right lenght to the main gear.
The main gear was of the pinion when it fell, I heard the wizzz. Tx was
set at soft, so thruttle was down as soon as it fell, droped, or crashed.
Did not think the feathering shaft could be the cause because there is
no apparent wooble, the main shaft neither it is straight.
But you guys know more than I, these parts will be checked this afternoon.
Thanks.
Later :dance

Wrench 54
07-21-2009, 02:38 PM
Hey Sly, I got a new set of woodies from over there ( China ) when I was breaking blades everytime I tried to hov my K2 that still to this day cant get them to track right. They were the cheepies you get on line, I've also had some that I had to take the rod off and turn both ends just a smuge ( less than 1/2 turn ) to get them to track, I learned never to buy just one set because you never know what you are going to get. Also like Supra6 said double check everything. Keep The Rotors Spinning and LOL Wrench

LEONARD ANDERS
07-21-2009, 03:11 PM
Sly when you track the blades try to hover about 3 feet off the ground , i had a set of blades that wouldnt track strapped down , but a few adjustments in the air they flew great until i flew into a fence Hope this helped

sly the dogman
07-21-2009, 05:14 PM
W, ordered those blades from over there (china) on the 7th of June
and I'm still waiting, that's why I thought that the blades on the heli
were dead meat. I ordered some from an american dealer, should get
them on the 24th or 27th of this month. LoL
Did not have time to play mechanic today ; maybe I'll try to track new
blades before looking for a bent shaft.
Can I hover around with these popsicle sticks ?
Later :dance

Nozer
07-21-2009, 06:02 PM
I could tell you right away that your featheringshaft is bent. It dosnīt take much to bend the damn thing.
If the blades so much as touch the ground, its done...

I have had close encounters with vegetations on landing. It is a perfect landing, but the blades acts as a lawnmover and cuts some grass = bent featheringshaft.

So if your heli "dropped" and the blades hit the ground, theres no question about that itīs bent.
Flying wit a bent shaft, will result in damage to your bearings.

/Tobbe

sly the dogman
07-21-2009, 08:49 PM
Tobby and most of you guys where wright, I changed the feathering shaft,
put in a stronger on (they're a bit longer than the original) and the tracking is
better not perfect, at least the blades don't go underneath one an other.
There's still space between them but for now I'm ok with that.
Thank you very much.
Later :dance

ChrisJ800
07-22-2009, 12:47 AM
I use the xtreme titanium turnbuckles. They make adjusting for tracking much easier without having to take off a ball link each time. Also you can do as small an adjustment as you need rather than a full 180 degree turn.

Mind you I still cant get the woodies to track well. Carbon blades are good though, but expensive.

PittJitsu
07-22-2009, 04:55 AM
I could tell you right away that your featheringshaft is bent. It dosnīt take much to bend the damn thing.
If the blades so much as touch the ground, its done...

I have had close encounters with vegetations on landing. It is a perfect landing, but the blades acts as a lawnmover and cuts some grass = bent featheringshaft.

So if your heli "dropped" and the blades hit the ground, theres no question about that itīs bent.
Flying wit a bent shaft, will result in damage to your bearings.

/Tobbe

+1:thumbup: I have never NOT bent a feathering shaft. They are insanely fragile. My biggest tip? Don't crash or hit anything, land softly, take off gently.. Whalla! All fixed!:YeaBaby:

sly the dogman
07-22-2009, 11:50 AM
Chris,
where can I take a look at those titanium turnbuckles ?
I'm curious. :dance

sly the dogman
07-22-2009, 01:39 PM
Today tried to ajust the tracking a little bit better, and
guess what ? the blades do exactly the same thing as before
they get on top or below one an other but never track.
Can't wait to get the new blades and check'em out.
Any ideas ??? :dance

PittJitsu
07-22-2009, 04:22 PM
Chris,
where can I take a look at those titanium turnbuckles ?
I'm curious. :dance
Here you go.

http://www.miracle-mart.com/store/index.php?main_page=product_info&cPath=110_176&products_id=1550

sly the dogman
07-22-2009, 04:37 PM
simply facinating.
thanks:dance

molehunter
07-22-2009, 05:00 PM
Hi sly,
I'll go with what the others have said but the first item I check after a doink, is the fly bar holder and its crummy little pivot. Check for breakage or play. If this is not A1 then the whole rig is going to be out, bad tracking = extra vibes and then gyro tripping out.
Good luck:Fan

sly the dogman
07-22-2009, 08:24 PM
Marty,
Can it be said; that if the flybar is bent in or near the flybar holder
than the blades are very hard to track, causing them to get on top
or beneath each other, while ajusting the links.
Is that where my problem lies ?
Later.:dance

Wrench 54
07-22-2009, 08:56 PM
Hey Sly, Guess this is the week for not being able to get blades tracked, I just put on a main shaft/flybar/feathering shaft/ new extreme blades and I just spent app 4 hrs trying to get the blades to track and the pitch right, the blades would track then just go hey wire no matter what I did ( sounds like your problem?? ) I found the flybar center holder has plastic pins that run in the bearings with screws on each side, well one of the pins had broke off and was letting the bar move around which was affecting the pitch on one blade, I didnt see it till I got looking at the blades moving when I added pitch and one blade seem to be moving more than the other, with all the other stuff on the center holder its hard to see but it was doing a twist type move instead of up and down. Im still putting the head back togeather for the 20th time and will let uou know if this cures my problem, you may want to just double check yours might be the same thing. LOL Wrench

Wrench 54
07-22-2009, 10:24 PM
Just an up date for you Sly That was my problem blades tracking right on now, I was starting to think I had done some serious dammage to the K2 and had tore the head apart many many times looking for something wrong and still didn't see that part broke, hey it was doing the se-saw ok and so I didn't think there was a problem with it. This will be one of those things to keep in the back of the mind if it happens again, I would deff check yours real good it may be the same problem. Hope this helps, It looks like there is a few of us all kinda on the same page with these K2's so lets all learn togeather!! LOL Keep The Rotors Spinning Wrench

Magenta
07-22-2009, 10:36 PM
I've gotten the blades to track perfectly, flown a battery, put in a new battery, and the blades aren't tracking (wood blades)

I've given up on getting them perfect. PDC (pretty darn close) is good enough for me

PittJitsu
07-23-2009, 03:41 AM
Marty,
Can it be said; that if the flybar is bent in or near the flybar holder
than the blades are very hard to track, causing them to get on top
or beneath each other, while ajusting the links.
Is that where my problem lies ?
Later.:dance

Here is a very safe bet on fixing your problem. Go buy a Feathering shaft, main shaft and flybar. look very carefully as you change these items and I will bet you fix your tracking.

sly the dogman
07-23-2009, 07:40 PM
I got the blades that I ordered from a US dealer(4 days) vs china(44 days)no comment !
Installed them and "voila" nearly perfect, with little effort. But the flybar leans
a bit backward when it rotates. So next order, flybar, main shaft, turnbuckles,
got the feathering shafts.
Is the stainless main shaft stronger than the stock one ?
But I will still look at the flybar holder and the pivots very carfully.
As for the flybar that leans slightly backwards, it's not a good idea to try
to fly, even hover, right ?
Back to the waiting room.....
" can I offer you an Rc magasine", sir ? While you're waiting, here's one on helis......
Thanks a lot guys.
Later :dance
___________________________________________
garaged King 2

Wrench 54
07-23-2009, 09:17 PM
Hey Sly, I ran 10 batt packs today and the K2 is still in one piece so Im not going to push my luck it is time to set down and look everything over. Looks like you are getting close to having it all right, as far as the flybar tilting back are you sure its not the main rotor tilting foward a little and it makes the flybar look that way?? I dont think I have ever seen that on my K2, I've had soooo many strange things I've lost count. i'LL Sleep on that one. Good Luck Don't Give Up. Keep The Rotors Spinning Wrench

ChrisJ800
07-24-2009, 12:40 AM
Hey Sly. I wouldnt ground yourself over a flybar. Just take it out, straighten it as much as you can and put it back. Make sure when you put it back that you get the servos at mid (zero pitch) throttle stick position and that everything is then parallel (paddle control arms, Hiller control arms etc) and that the paddles are parallel with each other and level with the swash.

I say this from recent experience as mine weren't until it was pointed out to me on another forum.

sly the dogman
07-24-2009, 08:27 PM
Hey, I found out why the blades leans a bit backward when spooled up,
rubber O ring in the blade grip is missing, yaba-daba-dou !!!
Happy times folks. I don't crash'em, I loze parts, great.
Later :dance

ch47dfe
08-11-2009, 03:17 AM
Also what makes a big difference on tracking blades is to balance them as a pair....You'll gat a smoother flying heli whan the blades are balanced....Also when you put the flybar back in, make sure that its completly centered in the flybar holder by measuring the ends....should be exactly the same distance on either side... then install the paddles and measure them too....

Paul