Servo Query

[Chris FellowsParticipant @chrisfellows72943]

Hi All

Just fabricating the mounts for the rudder servos. For the Huntsman 28 I'm using this Hitec Low-Profile servo as height under the cockpit floor is restricted.

As well as the usual different arms and the four screws there are four rubber whatsits and four metal sleeves. I'm assuming that the former are rubber mountings, though they are a tight fit in the servo mounting holes. Are these for aircraft use?

I've had a look on the Hitec site and downloaded a "manual" but there is no mention of these parts.

Usual practise seems to be just to use screws but do I use the sleeves as well or are those for the rubber mounts?

Thanks, Chris

PS There are four sleeves but one decided to throw itself in the corner behind the units! I can see the blighter though, surprisingly!

 

Edited By Chris Fellows on 25/05/2020 15:43:04

[Chris FellowsParticipant @chrisfellows72943]

[Dave Smith 17Participant @davesmith17]

The rubber grommets are to dampen vibration when the servo is being used in an engine powered plane or boat, the correct use of them is to push the grommet home on the servo lug, then slide the metal tube through from underneath so the flange is against whatever the servo is being mounted on. This prevents the screw from putting too much pressure on the grommet.

I doubt that the vibration resistance is needed in most scale type boats, but I still mount them that way out of habit.

[Dave MilbournParticipant @davemilbourn48782]

Chris

This should explain it, although you needn't go as far as to make a special tool for the job. I use an old school compass…

Servo mounting grommets

Dave M

[Chris FellowsParticipant @chrisfellows72943]

Thanks chaps

It all makes sense now!

Mr. Milbourn, do you actually use them? The servo in the Huntress is just screwed in as it is in the Club 500 which gets more abuse as it's used for racing and no problems.

When I say the grommets are tight, they are very tight and very hard to push all the way home. Some oil would help I suppose.

Chris

Edit: with the aid of soft soap I've got them in Ok and the eyelets went in alright by hand. As I've got them I may as well use them.

Edited By Chris Fellows on 25/05/2020 18:39:25

[ashley needhamParticipant @ashleyneedham69188]

For I/c use I can see that rubber grommets might be necessary, but for anything else?? I just screw mine in. Early on I just had them sitting in a closely fitting box! No probs.

Ashley

[Ray Wood 3Participant @raywood3]

Hi Chris,

I think they they are worth using, just looks a better job !I

The eyelets are really useful for loads of things when you build a yacht 😄

Regards Ray

[Dave MilbournParticipant @davemilbourn48782]

Mr. Milbourn, do you actually use them? The servo in the Huntress is just screwed in as it is in the Club 500 which gets more abuse as it's used for racing and no problems.

Mr Fellows

You have that particular model. I built it several years ago and so I can't remember whether or not I used the brass eyelets in it. However the original question wasn't related to my own use of them – you asked it and I posted what I'd hoped was a helpful reply. That said, I've been making these things for over 50 years and I don't need to rely on spacers to indicate whether or not the servo screws are overtight.

Suit yourself.

DM

[Chris FellowsParticipant @chrisfellows72943]

Hi Dave

Sorry, I didn't mean it to come over like that, just wondered if you ever used them at all?

As ever, your reply was very useful and told me exactly what I wanted to know.

It was just funny after looking at that special tool, that after I'd got the grommets in the eyelets went in a treat.

Chris

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