Servo bumpers

[ChadCarlin]

Hey guys, I keep seeing pictures with some of you having bumpers on the servos so the canopy doesnt rub on the servos. It looks like there are a few different versions, can anyone share with me how you made yours?

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[A VIKING]

Sorry for the delayed response...I have been away.

This is my version for the canopy/servo bumpers.
It consists of a cap head screw, short aluminum tube spacer and rubber automotive vacuum cap.

I cut my vacuum caps to 14mm.
Push the vacuum caps on the cap head screws until the head of the cap screw is seated or bottoms out in the end of the rubber vacuum cap.

This is important to create a firm rubber tip when assembled. If the screw does not reach into the rubber cap far enough the rubber cap will roll over from pressure applied by the canopy when installed.

Now thread the cap screw with rubber cap installed into the servo mount until the rubber cap just contacts the servo mount.
Pull the rubber cap off without turning the cap screw and measure the exposed shank of the cap screw between the head of the screw and servo mount.
This will be the dimension of the aluminum tube you will cut to slide over the screw on final assembly.
If you don't want to make the aluminum tube spacer, that's OK because I flew my Velos a long time without them but decided later on it would be best practice to make and install them. They make the rubber bumpers fit perfectly on the cap screw without movement.

On final assembly don't forget to use some thread lock on the screws.
That does it...both canopy and servo are protected from each other.
If you notice in my last two photos, I also installed servo shims under all four servos (the gold color) which did two things for me. It aligned the Expert servos up a little better with the swashplate and by moving the servos in toward the mast and it also created a little more clearance between the corner of the servo and canopy.
It works perfectly.

If you look closely you can also see the tip of the rubber cap flattening out because of contact with the canopy. It will flatten out with time so to tighten the assemble up you can simply rotate the rubber bumper 90 degrees on the cap screw and let it wear on a new rubber surface. Once you run out of wear surface on the rubber bumper you simply change them out.
You won't have to think about that for around two hundred flight based on what I see with my bumpers.


Bumpers installed.


Bumper close up.


Rubber cap removed to show cap screw and spacer.

[ChadCarlin]

Thank you sir! Exactly what I needed!

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