Micro tail blow out

[danhampson]

Just got my 130x back up and running after replacing the main gear so thought that i would take her out for a flight all was going well tail in, left side in, right side in, all good or so i thought.
i changed the battery used that doing so FF landed and change the battery again, back to doing some more FF about half way through the pack i thought that id try a loop (like ive tryed on the sim loads of times), so i gained some altitude and forward speed flipped into IU gave it max collective and pulled back on the elevator as the nose was pointing straight up the tail blew out making it piro out of control, i regained control and landed the bird.
i inspected the tail gears front and back (no teeth missing and mesh looks fine), so decided to give it another go. i took off got myself ready and again as the nose was pointing to the sky the tail blew out again, this time i wasnt so lucky i couldnt regain control so at about 10' i hit throttle hold to try and minimise the damage.
I ended up with a broken main shaft and broken bevel gear (just ordered the parts)
Does anyone have any idea why the tail might be blowing out during a hard collective maneuver?

 

[Westy]

what is you gain set to on IU?

 

[danhampson]

didnt touch the gains in the tx just followed the manual for the dx6i setup and then adjusted the D/R & expo to calm it down a bit.

 

[xokia]

your are probably loading the motor down to much. When you do your loop are you trying it at full throttle? Or are you going to mid stick when you pull back on the cyclic? My guess is you have to much cyclic and collective coupled with to much speed and you are just bogging the motor down.

Its kinda hard to blow out the tail on the 130x unless you use way to much collective and cyclic at the same time. Which even then the tail kinda holds but the helicopter kinda rotates some because of the lack of power in the tail. Once you fix the problem you can regain control pretty quickly. Its not like the mcpx that completely blows the tail out.

 

[danhampson]

ive stripped the tail drive down and the rear gear attached to the TT seems to be slipping under load, it works when there is no resistance but if i hold the tail and turn the head the TT just turns.
Would it be ok to put a drop of CA on the gear/shaft i think that would probably fix the issue.
i was using full collective and about 3/4 cyclic so i dont think that would have helped.

 

[xokia]

Stripped D gear that will do it. Yea you can use a tiny amount of CA but I'd replace the gear myself.

 

[danhampson]

ok i'll replace the gear when the other parts turn up and let you know how it goes.

 

[xokia]

ok i'll replace the gear when the other parts turn up and let you know how it goes.

yea that should fix it. When you replace the gear make sure the shaft goes to the end of the gear. If it doesnt adjust the tail TT by loosening the frame and pushing it in more. I've stripped a couple of those out myself. It seems to be hit or miss, the one I have on there now has lasted through numerous crashes. I really think you just need to get the shaft and torque tube setup correctly to get them to last.

Another thing to check is a cracked main shaft, it is what was causing my D gears to strip. Sounds crazy but the vibration of the tail caused from the cracked main shaft caused all kinds of havock.

 

[danhampson]

The main shaft is broken in 2, just below the collar. ive order a solid carbon shaft and a metal bevel gear (just because they are out of stock of plastic). It looks like the tail has been pushed in a bit the TT end is poking out of the D gear quite a lot

 

[xokia]

The main shaft is broken in 2, just below the collar. ive order a solid carbon shaft and a metal bevel gear (just because they are out of stock of plastic). It looks like the tail has been pushed in a bit the TT end is poking out of the D gear quite a lot

Yea pull the TT out of the frame some then. Only part of the shaft is beveled if you push it to far you are pushing the round portion of the shaft into the "D" portion of the gear and not getting the full bite.

I haven't used those metal gears other than the one on the main shaft. The tail gears hold up well if set up correctly. I've only replace mine I think twice.

 

[danhampson]

its the one on the main shaft that ive ordered i have already got some of the D gears, 1 that came with the heli and a packet of rear tail gears i ordered a couple of days ago.