Does the Hitec HS55 servo need a grommet or will a simple screw be enough? If a grommet is needed where can I find them?

If you are installing them in an electric powered plane you don't need the grommets. The main purpose of servo grommets are to isolate the servo mechanism from the vibrations caused by the engine. With electrics these vibrations aren't an issue. Mount them with a screw. Many instruction manuals for park flyer size planes will also instruct that you can glue the servos in place with CA adhesive. However, I myself don't like that option.

Ken

Since this servo is generally used in small aircraft, often electric, a grommet is not as important. If I remember right, it is not intended for one.

if you are flying with a glow engine a small piece of fuel line can be an effective option.

If you are talking about the metal grommet you don't need it. It's only purpose is to keep ham fisted modelers from over tightening the rubber part. As OzMo says the rubber part can be simulated with a short piece of fuel line.

I will also add that hot glue is an excellent method of attaching those little hitecs in a foamy.

Be careful of that hot glue. I have seen people deform the cases on the servo to the point where they wouldn't work.

Just thinking the same thing...
I got just a wee bit carried away one time w/ the foam safe CA and some of it seeped into the upper part of the case and got into the gears...[:@]

If you're using your 55's in an elec. powered airplane, you don't need grommets.

The metal grommet is typically referred to as an "eyelet". It's purpose is as described. The rubber portion is a grommet.

Yeah, I put the hot glue in first then quickly push the servo on top of that. It doesn't move, and that time delay will help prevent any warping of the case. I was concerned about that warpage when I first used the hot glue.

By the way, what's nice about using the hot glue is that, in the event of a complete destruction crash, you can pull the hot glue off. It takes a little effort, but it comes off. Don't ask how I know that..

The terms are interchangeable, at least in common use. [8D]

http://www.merriam-webster.com/dictionary/grommet
http://www.merriam-webster.com/dictionary/eyelet
http://en.wikipedia.org/wiki/Grommet

(Edited to get my words out of the quote)