Rubber servo grommets

[Philimon]

Hi Folks

I'm about to look stupid when I ask this question.....

Being a newly converted plank flyer, I've always fitted the rubber grommets and eyes to servos when installing them in planes. Now that I've built my first heli, I've installed servos without them. I remember reading somewhere that thats how it should be done on heli's, as it introduces too much play/slop on the controls.

Am I right? Should we not use those rubber grommets?

Regards
Andrew

[SRH990]

I always use the rubber grommets with nitro helis but not with all electric heli. Obviously the mini helis use servos that don't have grommets anyway but I don't use them for the 3 swashplate servos on my Trex 600 although I do for the 9254 tail servo. On my E550 if you don't use the grommets on the servos they are too deep for the links so I did use them on this heli.

[LipolyGone]

I dont think thats right phili
The grommets are there to isolate the servos from any vibrations from the engine & airframe, if you remove them you are likely to kill your nice new digital servos very quickly.
The other thing I see people doing with rubber gromets & the brass bushes is installing the bush incorectly. The brass bush should be inserted from behind the servo flange & not from the top of the servo i.e the flat flanged end of the bush actualy sits on the airplane or heli frame & the screw tightens up against the smallest end of the bush.

Martin

[Made2Fade]

Best thing i would think, would be to use the little servo retaining plates on all ya servos instead. I normally use the quick uk ones. Use the rubbers then these over the top. You get the best of both worlds then.
Heres a pic of some:- http://www.quickuk.co.uk/acatalog/servo_400.jpg
Lee

[Ade_Law]

defo use the grommets plates are quite useful too to help spread the load into the rubber better.

Ade

[Philimon]

Thanks folks. Rubber grommets it is then. Even on the rudder servo.

[Nutz]

Whats the word on eyelets, as I have the grommets and servo plates but I have not installed the brass eyelets?

[jimbob]

The purpose of the eylet is to stop the grommets from deforming such that they no longer perform the isolation.

Also, they assist in the centring of the scew in the hole and the grommet in the servo plate, thus evenly spreading the load.

I would advise still using the eyelets in the grommets.

[Mercuriell]

I don't use the brass eyelets but use care in tightening the screws down so as to only just start to compress the grommets - can't see any point in not using the grommets = if you put them on right there's no appreciable slop in the servo.

[Steve]

Do exactly as it says in the build instructions for the heli.

They vary. All IC helis say use the rubber grommets. Some say use the eyelets, some say don't. Some say use metal plates, some don't. Some even have different mounting setups for different servos on one heli (from memory, the Freya uses plates on the pitch servo, but not on the cyclic servos etc).