130x spinning uncontrollably

[Big Dogg]

The tail on my 130X had been shaking quite badly the other day, so I reset the gyro settings as per blades instructions. However, it didn't seem to stop the tail shaking, then after a few seconds in the air, the heli just started spinning uncontrollably (I think it was CCW direction, but not 100% certain). All gears etc seem to be intact and I can't figure out what's causing this to happen.

Can you give me an idea of a few troubleshooting steps to try to find what's causing this problem?

Thanks in advance.

[Stanley Speel]

That is probably the tail blowing out - try moving the tail servo a couple of mm more up the boom and keep doing (within reason) until it fixes it.

[tomatwalden]

The tail on my 130X had been shaking quite badly the other day, so I reset the gyro settings as per blades instructions. However, it didn't seem to stop the tail shaking, then after a few seconds in the air, the heli just started spinning uncontrollably (I think it was CCW direction, but not 100% certain). All gears etc seem to be intact and I can't figure out what's causing this to happen.

Can you give me an idea of a few troubleshooting steps to try to find what's causing this problem?

Thanks in advance.

The tail spinning uncontrollably is the "C" gear stripped. The gears LOOK fine, but they're not ... trust me! They're loads on this problem if you search for it. As the 130X has a torque tube to drive the tail - it's very sensitive to anything stopping the tail rotor from spinning - even a bit of grass momentarily will strip the gear.

The reason the gear looks OK is because it strips internally - not the visible teeth. It has a "D-shaped hole which keeps it from spinning on the torque tube in the tail. It's this D shape that strips, and because it's internal to the gear - you can't see it.

Simple test to verify. Hold the tail rotor still, then turn the main blades by gently turning the main gear. If you can turn the main gear whilst holding the tail rotor still - your C-gear has gone.

Its a £3 part (for a pack of two) - you get a spare in the box with the 130X. It takes 10-mins to fix, but can be a bit fiddly! The following vid can help if you've never done this before - but bear in mind that for just the "C" gear - you do not need to disassemble the whole tail as shown here.

HTH - Tom.

[Sheldrake]

Hi There had the same problem on mine. If you find the 'C' gear is OK check the 'A' gear because the original plastic ones strip very quickly even without a crash or hard landing. On a previous thread I reported how mine went on the fourth or fifth pack!

Recommend the metal upgrade.

There is a report on it on this website with a few photographs. It is not obvious until you have had it happen once and know what you are looking for!

http://www.leicestermodelhelicopters.org.uk/

Good luck with it. It really is a fabulous heli for the money!!

[Big Dogg]

I've already upgraded the tail gear that sits on the main shaft to a metal one (I stripped the original plastic one early on). I will check that C gear and also if the tail servo has moved down the tail boom a bit. I'll keep you updated. My guess is the C gear. I think (and hope) I have a spare here lol.

[dillwhacker]

You can quite often fix a stripped 'C' gear with a small drop of CA to bind it back onto the drive shaft (TT).
Don't get any CA on the teeth..............
HTH

[kylelnsn]

You can quite often fix a stripped 'C' gear with a small drop of CA to bind it back onto the drive shaft (TT).
Don't get any CA on the teeth..............
HTH

My Money is also on the C Gear, however not there have been instances where the tail servo has failed, or as others have suggested move the servo down the boom a bit to get the correct angle of attack on the tail blades. Keep us updated!