Tail gearbox moving (i.e. coming off!)

[dodgey]

Heya - I've replaced my boom with a black one, which is shiney and smooth. Immediately I now have problems with the whole gearbox moving down the boom so the gears miss each other (and of course strip).

This is compounded by the fact the 4 tiny screws that clamp the gearbox onto the boom no longer bite properly (plastic internals is clearly threaded now). They have never "bitten" properly but I've not suffered the gearbox shifting. Clearly the new shiney smooth boom is bringing the lack of grip to the fore.

Has anyone got any suggestions on what to do? Ideally longer screws, or nuts and bolts would do the job but they are so damn small I haven't anything that will come close to fitting

[clear4takeoff]

Well, the tail gearbox has always been the weak spot with the Shogun V1 and V2, IMHO.
I go aftermarket. The CF boom is a little bigger in diameter, and there are CNC gearboxes out there made for it. Prices have come down quite a bit.

[dodgey]

You know what - As soon as I switched back to my 1050 Mah pack from my 2100 pack all the problems subsided.

I was somewhat suprised at the massive increase in headspeed from a pack with the same volts but I'm assuming teh much larger capacity pack allowed more current to be drawn - nto sure. kinda sounds right.

Since I've gone back to my baby pack, teh headspeed is gentle and the tail seems happier with less demand on it.

[mike the snake]

That is the shoguns's weak point! You can't get a high headspeed without blowing the tail up!
I had fits with mine until I dropped the headspeed down. Tail blowing up in the air, boom slipping, belt always coming loose, bending tail rotor shafts in the air.
On mine, the tail was balanced statically, but when spooled up it was different, this caused serious resonant vibration that hit instantly once the RPM got to that point.
I strapped the heli to a stool, spooled it up, and felt the tail by holding on to the vertical stab (Carefully). Once the resonant rpm was reached the tail vibrated violently. I then added a piece of tape to one blade and spooled it up, the shaking was worse, so I swapped the tape to the other blade and it went away!
The higher HS caused the tail to shake which makes the boom slip in it's mount and loosens the belt, messes with the tail linkage, wreaks havoc (It's unbelievable when you actually feel it!).
I have MANY smooth flights since, I am gradually raising the headspeed back up, it's around 2300 or 2400 I think now. Flies well.

[playfair]

I put a drop of thin CA where the case meets the boom once everything was positioned, but not socked down all the way. Still comes off when you need to replace parts, and the glue can simply be scraped from the tail case.

[mike the snake]

If the boom is moving due to the tail shaking, not even CA will hold it in place.
If it's simply a matter of the clamp not working well enough then it should work fine.

[dalars]

the tail is indeed a weak point.
I strenghten them by coating the 2 halves with exopy (carefully) to make the plastic frames more durable, before mounting it.
then once I have it on the tail, I drill a small hole through, into the boom and insert a screw to lock it to the tail.

I also coat the tail blade grips with epoxy to give the little tits more strenght. they snap off way too easily.

better life through epoxy.

D :cool: