Gents,

What actually holds the needle roller (S4349) in place, and refrains it from not sliding down (or up)?
It does feel like a good fit after being pushed into position. However, today while airborne, the needle roller came off in flight, and consequently the inner scissor disconnected, luckily I managed to land with no damage.

See attached PDF highlight.

Grateful for your thoughts, if anybody remembers this.

cuatrotailassembly.pdf

Robbe Nova Cuatro Gas/Nitro, Futura Nova Nitro, Futura SS Nitro, Vario Scale S300C/1002/21 Gas.

Darn it, I found the answer myself... I forgot the S0041 that locks it in place. Why is this not indicated to be lock tied? Sorry. An amateur I am. Anyways, lesson learned. Case closed.

Robbe Nova Cuatro Gas/Nitro, Futura Nova Nitro, Futura SS Nitro, Vario Scale S300C/1002/21 Gas.

Because you don't use Loctite Threadlocker on plastic. The friction between the plastic and 0041 is sufficient to keep the setscrew from opening.

Ramster

Because you don't use Loctite Threadlocker on plastic. The friction between the plastic and 0041 is sufficient to keep the setscrew from opening.

Hi Ramster,

Thanks for your reply.

I'm using the upgraded Robbe tail rotor gearbox S1009 (see attached PDF), which is made from aluminium. The S1009 build instruction doesn't show the installation of the set screw, and this is where I made the mistake, and forgot (inexperience), to install the set screw, which in this case would call for the use of loctite.

TAIL-ALU-ROBBE-UPGRADE-S1009.pdf

Cheers,
Claus

Robbe Nova Cuatro Gas/Nitro, Futura Nova Nitro, Futura SS Nitro, Vario Scale S300C/1002/21 Gas.

Ok, also since S4349 is hardened and setscrew S0041 doesn't "bite" into it because it is a Cup-Point style tip screw, a better option would be a Flat-Tip type setscrew.

Cup-Point:

Flat-Tip:

Grind a small dimple in the pin for the grub screw to locate into..

"Believe none of what you hear, and only half of what you see." • Benjamin Franklin

Ramster and dgoss999,
Great advises, highly appreciated, thank you.
Cheers,
Claus

Robbe Nova Cuatro Gas/Nitro, Futura Nova Nitro, Futura SS Nitro, Vario Scale S300C/1002/21 Gas.