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Yeah it is... Im still new at these little micro heli's, and I gotta say, they are really simple by design, and easy to work on compared to a collective pitch heli which has alot of parts in the rotorhead, and like 5 servo's, and needs constant inspection and fine tuning. Never again... Whew ! I spent more time inspecting and adjusting than I ever did flying the thing.
Now I just charge, cool, fly, cool, charge cool fly, and life is good
Are you talking about the dogbone links ? Thats good info there. I havn't experienced that yet with mine, but im glad you described the symtoms of one or both being past the balls (after crash issue). That would be alot better than losing one.
I hope thats the worst thing that ever happens to mine. lol
On mine at least nothing was stripped. Not even any wear on anything. It was simply that the pop joints had got pushed in too far.
I've just done a test on mine and with one upper joint set wrong it doesn't hover as well, sort of weaves about a little. With both upper joints wrong it gets much worse. Three joints set wrong and you really can't keep it in the air!
hc said:
So who can wait till tomorrow when you have a bench with magnifiers, microscopes and tools!
Believe I found the problem…the yoke for the top rotor was sheared off….so the blades wont stay stable. Gonna see if it glues else wait for my spare parts…unless Dennis has a spare he wants to throw in the mail? 🙂
I'll see if that fixes it….but…many thanks to all of you that replied with great things to check!
Are you saying the splines on the shaft are slipping inside the upper yoke ? Yoke is stripped inside ?
Sorry, all my parts are on Yellow and Blue, unless ya need a tail rotor blade, I still have both spares of those.
Hmmm… 11 and 12 ? Hmmm... Oh ! 23 ! here goes ! lol
Heliman said:
I had a similar thing happen to mine, it was so unstable you really couldn't fly the thing. I discovered in the end that the buckles (the dog bone things mentioned above) can get pushed too far in causing instability. It's like a tiny ball and socket joint and the socket should only just pop over the ball. If you can see the ball clearly sticking almost through socket then you need to pull it back into the correct position with a thumbnail. You will hear a slight click.
Any one of the four joints can cause the problem. It can vary from a slight wobble in the hover to being vitually un-flyable.
Good one ! Thanks ! I just added that to my notes. I completely overlooked that posibility, and thats a darn good one.
So who can wait till tomorrow when you have a bench with magnifiers, microscopes and tools!
Believe I found the problem...the yoke for the top rotor was sheared off....so the blades wont stay stable. Gonna see if it glues else wait for my spare parts...unless Dennis has a spare he wants to throw in the mail? 🙂
I'll see if that fixes it....but...many thanks to all of you that replied with great things to check!
Comparing to the other S107 in our lab....it appears that the top rotor assembly and stabilizer bar is....lack of a better term...floppy. Its sitting at rest around a 45 angle where the other is maybe 10 degrees down. Im guessing its something in that top assembly, so gonna take it apart tomorrow and see what I can see...
I had a similar thing happen to mine, it was so unstable you really couldn't fly the thing. I discovered in the end that the buckles (the dog bone things mentioned above) can get pushed too far in causing instability. It's like a tiny ball and socket joint and the socket should only just pop over the ball. If you can see the ball clearly sticking almost through socket then you need to pull it back into the correct position with a thumbnail. You will hear a slight click.
Any one of the four joints can cause the problem. It can vary from a slight wobble in the hover to being vitually un-flyable.
Something it off center, out of balance, or a shaft is bent, hense the wobble.
Look at the top blade grip, grab a blabe tip and push pull back and forth, The blade grip should only move maybe 1/16 inch max.
The flybar attachment should not have any slop, keeping the flybar centered to the shaft. Again, the upper blade grip is ok if it only moves back and forth about 1/16th inch, but the flybar should stay perfectly centered to the shaft.
If it's having trouble lifting off, and wants to rotate, look at the gear teeth for wear (slippage), and also alignment with other gears teeth. Check alighment with the heli verticle, and make sure the shaft moves up/dn freely maybe 1/16 th inch.
Now hold the heli up by the flybar, and check all that again, for proper alignment.
At no time, should any meshing teeth of the gears, ever be NOT fully on the teeth it's meshing with, no hang over of teeth.
Now look in the side of the chassis, and see the two big gears on the main shaft.
The top gear is for the lower blade. Hold that gear from turning, and make sure you can't rotate the lower blade without that upper gear turning. Is anything slipping beside the gear in your fingers ? If so, BINGO !
Now do the same with the lower big gear and the upper blade grip. Don't twist it by the flybar for that test please.
If nothing is slipping, how old are the motors ? Have they been subjected to crashing and leaving the throttle on
You may have a motor going out, loosing rpm, or getting erratic due to poor contact between the commutator and the brushes.
If one of these tiny motors gets too hot, or the brushes have arc'ed alot from excessive load, the delicate brush springs can loose their strength to push. Are we getting close ? Dennis
All good suggestions. Lets discount the effect of environment..breeze from the fans, lights, etc because others are flying correctly (even another S107).
It wont really hover and take off. It wants to simply throw itself off the the left and not take off. If we hold it up and let it take off from then hand, it veers off course immediately. No hovering even trying to compensate with the controls.
Dogbones are intact, top blades follow the flybar...so everything looks OK there. The shaft looks straight best as I can see.
Tail rotor is not spinning, but can be controlled.
It was mentioned it looked like it was vibrating alot....not excessive but maybe a lil more than it should be?
When i do try to take off...it starts....wobbles around pretty bad and then just sheers off
If the tail rotor turns at neutral right stick, remember these are infra red (terahertz), so things like bright lights, sunlight, TV's, and other things can affect it. Make sure you don't have something turned on nearby that might be messing with it.
Hopefully, moving the battery slightly forward will fix er up. Dennis
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