Need advice about front tail-drive brass gear in E360

[OrbitalGolem]

Had the boom shift backward on flight #46 of one of my E360s and lose tail rudder. TH and dumped her in soft grass. I had to replace the "front tail drive gear set" which includes the brass gear that is driven off the main gear. Everything comes disassembled in the packaging. I inserted the supplied jesus pin in the brass gear to lock it to the shaft, got everything back together, and headed out for a flight.

Smooth spool-up, everything looked good. I go inverted and suddenly lose tail rudder. TH and dump her in the grass, yet again, though I being much lower to the ground than last time, I lose the feathering shaft, main shaft, main gear, etc. etc.

Post-mortem analysis reveals that the jesus pin in the brass gear was ejected and nowhere to be found. Holy c***.

I literally have no idea why this happened. The pin inserted smoothly and both ends were flush with the gear assembly. What did I do wrong? I'm at a loss to explain.

What really annoys me too is the need for a second $14 carbon fiber rear fin and a "hardened" replacement main shaft. I guess those 350mm blades do have quite a bit of inertia even when TH is hit.

[nickyd]

The tail drive gear sets have always come pre-assembled when I have replaced mine.
Thats really bad your pin popped out. I have seen on other parts of the heli that there is a plastic band around the jesus pin.
I dont know the answer but would see if you can maybe put some heatshrink around the pin and maybe a bit of loctite to seal it in.
I would complain to TT too as this seems to be either a quality control fault or bad design.
The ones Ive had pre-assembled are very difficult to remove this pin. I tried once and failed.

Hope you have better luck with your heli from now on, once this problem is sorted.

for ref:
http://www3.towerhobbies.com/cgi-bin...?&I=LXAFUZ&P=7 (belt)

http://www3.towerhobbies.com/cgi-bin...?&I=LXBBDF&P=7 (TT)

[OrbitalGolem]

Originally Posted by nickyd

The tail drive gear sets have always come pre-assembled when I have replaced mine.
Thats really bad your pin popped out. I have seen on other parts of the heli that there is a plastic band around the jesus pin.
I dont know the answer but would see if you can maybe put some heatshrink around the pin and maybe a bit of loctite to seal it in.
I would complain to TT too as this seems to be either a quality control fault or bad design.
The ones Ive had pre-assembled are very difficult to remove this pin. I tried once and failed.

Hope you have better luck with your heli from now on, once this problem is sorted.

for ref:
http://www3.towerhobbies.com/cgi-bin...?&I=LXAFUZ&P=7 (belt)

http://www3.towerhobbies.com/cgi-bin...?&I=LXBBDF&P=7 (TT)

I'll definitely contact TT and see what they say.

Here is the version for the E360 - very different from the ones above:

http://www3.towerhobbies.com/cgi-bin...?&I=LXCAAU&P=7


I still have no idea what the bundled screw is for. I'm really concerned that the problem will recur with the second kit that I ordered during the repair.

[Vaeloron]

My pin was starting to come out but I caught it early. I cut I small piece of shrink tubing with two holes for the pin. Then when I installed the gear I rotated the shrink tubing 90 degrees to offset the goes from the pin and shrunk it on. Hopefully it holds but I am still diagnosing a tail wag issue so I have only hovered with this fix. Good thing the wag happened as it is the reason I noticed the problem.

[Power Up]

Originally Posted by OrbitalGolem

Here is the version for the E360 - very different from the ones above:

http://www3.towerhobbies.com/cgi-bin...?&I=LXCAAU&P=7


I still have no idea what the bundled screw is for. I'm really concerned that the problem will recur with the second kit that I ordered during the repair.

I have the schematic and it implies the brass gear end of the shaft is tapped which would accommodate the 2 x 5 set screw, thereby stabilizing the pin. Sure looks like a nifty method of securing the gear/pin except the two I have on hand aren’t tapped. Perhaps they changed their mind after producing the schematic.
Anyway… I just applied a pin drop of thread lock into the hole on the shaft, lined up the brass gear and inserted the pin. Using this method I have never had any issues with disembarking pins…

[Power Up]

Follow Up: In the event a Mini T V2 T-Tube user stumbles across this thread and is having the above issue keeping the pin intact, the schematic I referred to in my previous post is correct. The shaft is tapped and the 2 x 5 set screw will secure the pin once installed.

The photo in the above link is incorrect; there is no head on the set screw. Requires a 0.9mm driver and is completely encased within the shaft once seated.

My originals slipped through QC with the shaft un-tapped. Led to a little confusion…

[OrbitalGolem]

Originally Posted by Power Up

Follow Up: In the event a Mini T V2 T-Tube user stumbles across this thread and is having the above issue keeping the pin intact, the schematic I referred to in my previous post is correct. The shaft is tapped and the 2 x 5 set screw will secure the pin once installed.

The photo in the above link is incorrect; there is no head on the set screw. Requires a 0.9mm driver and is completely encased within the shaft once seated.

My originals slipped through QC with the shaft un-tapped. Led to a little confusion…

Yup, my LHS figured it out and thankfully no problems since. Only 0.9mm driver he had was part of a $50 set. FleaBay came through and I think I paid $8 or $9 - smallest driver I've ever used.