whats a Servo saver

Its a sort of shock absorber that goes in the linkage to a servo. Thats something not to worry about on a plane though, it wouldnt help much on a impact with mother earth.

it might however cause your plane to crash. dont use them on planes full stop.
the saver is flexiable, and that will cause you flutter

Basically you suspend the servo output between two springs so that any shocks sent to the servo is absorbed (protect the servo drive train) while allowing the servo to move the control.

Servo savers are mostly used in r/c cars to protect the servo from severe jolts like running into something with a front wheel. There are a few types. One is just like a normal servo horn but it has a spring in it can turn without turning the servo. On many racing verhicles with bellcrank steering there is a cam with a spring on top of it so if it rotates it compresses the spring.

Servo savers are used on the servo that controls the nose wheel.
They are especially effective if you fly from bumpy grass fields.

A servo saver can keep you from stripping that rudder servo.

if you want to use a servo saver on your nose whell do it this way, or you'll get flutter and dieeeeeeeee
use the brass servo arm attachments that screw down onto the control, dont know the name for them, dont use them. and two the same, or brass collets. put a collet on the rod, then a spring, one from a pen will do, then though the servo arn brass thingy, then the other spring, and last the collet. you can do this at the wheel or servo. leave the servo brass bit with the screw out, as the wheel bumps it pushes the spring towards the servo arm, but the spring stops it, tension can be adjusted by moving the end collets in or out. this should be on a seperate hole to the rudder which should be solid.
there is a similar set up on RC buggies with brakes, attached to the throttle.
crappy drawing below lol

.....................................< collet
to wheel ===O/////o//////O=
..............spring^ ^ servo attachment