700l top servo grommets or not?

[nowler]

i never put the grommets or brass bushes in when i built it. is this going to be a problem for the servos with vibration?

it flies superb as it is by the way, i just assumed the grommets were for nitro vibration etc?

do people use them or not?

cheers

d

[Heli$]

I use them. I've never flown without them so I can't compare.

If it works well for you, it should be fine.

[nowler]

thanks for the reply.

is anyone else not using them? just curious if i'd be best placed hauling the servos out and fitting them?

cheers

d

[ticedoff8]

IMHO: I've always use the brass inserts on every model that I've ever built (fixed wing, heli, boat, car - nitro or electric).

And, I use the carbon fiber servo plate (http://www.aligntrexstore.com/Carbon...74A_p_818.html).
There used to be metal versions of this plate, or I made my own.

The brass inserts provide is spacer so you cannot over-tighten the servo screw and the servo plate clamps down on the servo's mounting lug

If you simply use screws through the rubber tab on the servo lug, the servo is not secure. It will rock and flex and it may actually lift out out of the frame mount under extreme load.
Because you are tightening the screw into a rubber material, you do not know when the screw is "tight".

I also mount the brass insert with the insert's shoulder positioned against the mounting frame - not against the screw. The way, when you tighten the screw, the inserts shoulder is acting as a washer against the mounting frame.

[nowler]

i'll clarify my setup:

no brass ferrules or grommets used, just the servo screws through the carbon plate holding the servo lugs into the location.

all screws are snug, servos are going nowhere, and my manual dexterity is good so the screws are not over tightened.

i'm not worried about the servos moving, they don't and haven't. i'm merely concerned with the fact that i've omitted any form of vibration dampening.....

cheers

d

[Lee2782]

I'm just in the middle of a 700 DFC build and asked the same question about using the rubber grommets plus brass inserts, I even asked Alan Szabo on Facebook and he said he uses them on all his builds

[RC/DC_5000]

I built a 600L without the grommets and brass on accident. I flew it and it was fine. I later built another of the same kit with the BL815 servos in question and it also flew fine. I agree that the brass insert also functions as a spacer though.

I don't think you are going to have a problem either way. It would be very easy to just put them on. I probably would. Just because I like things perfect.

[busterboy]

Not fitted on mine and flying without any issues.

[nowler]

cheers tim, looks great with the speed fuse!

that's what i wanted to know. do you use them in any heli?

[busterboy]

Originally Posted by nowler

cheers tim, looks great with the speed fuse!

that's what i wanted to know. do you use them in any heli?

I did actually fit them in my 700 nitro just to ease any vibration problems that might occur.

[Bigpops]

Always on a Nitro/gasser, optional on an electric, though some people will insist they should always be fitted.

With electrics, I tend to try the servo with and without and choose which give the best geometry on the pushrods.

On my 700E that turned out to be no grommets on the aileron servos, and grommets on the elevator servo.

[v58fuy]

On the 700l and top, if using the Align 815h servos, the grommets on the front 2 servos and no grommets on the rear swash servo will give the best geometry.

If you run grommets on the rear servo the pushrod will not be vertical, if you don't run the grommets on the two front servos, the same thing will occur - things are different with the DS 615's.

Therefore I run whatever will give the best geometry, if this is no grommets fine, if grommets are needed then fine also.

[macdad]

I use grommets with the eyelets and servo plates. Works great for me.

[rcflyerheli]

The grommets and brass eyelet are really intended not as a spacer, but is an isolation method to prevent vibrations from getting to the servo. I have some helis (Goblin 700) where they were used to get the geometry correct and others (Trex/Gaui) where I didn't use them.

In all honesty, I can't see any difference.

[K2Freak]

To me it was a question of how much vibration resistance I wanted. Personally, I would never use the copper liners - only the rubber or nothing. Align used to supply rectangular rubber bits with their servos that slipped over the whole mounting flange, and they would sandwich right between the carbon servo plate and the mounting surface. Worked great with the rubber squished in there. Since moving to SAB, I stopped using the rubber at all - straight to the mounts with the right spacing - and really haven't noticed any difference in performance.

[sammyha]

Originally Posted by v58fuy

On the 700l and top, if using the Align 815h servos, the grommets on the front 2 servos and no grommets on the rear swash servo will give the best geometry.

If you run grommets on the rear servo the pushrod will not be vertical, if you don't run the grommets on the two front servos, the same thing will occur - things are different with the DS 615's.

Therefore I run whatever will give the best geometry, if this is no grommets fine, if grommets are needed then fine also.

That's genius, I can't believe I haven't thought of that. It's the little differences that make all the difference...

[v58fuy]

You're welcome, my geometry is pretty bang on with grommets on the front two, but not on the rear servo - works great and good geometry.

David