HingeAct - Centering this magnetic actuator

The HingeAct magnetic actuator uses a spring for centering of the rudder control surface. The spring is the hinge of the HingeAct - it is a leaf spring made of plastic tape.

It is interesting to note that the HingeActs do not require magnetic centering, the hinge spring and aerodynamic forces also can contribute to the centering.

If the spring hinge is too stiff or the hinge is "bending" to one side, you can actually "stretch" the hinge plastic material and change the spring characteristics and alleviate any deviation issues. Sometimes the HingeAct will require a little stretch if it hasn't been used for a few weeks - the hinge material can shrink a bit - the polymer plastic has this stretchy characteristic - and maybe your control surface will be leaning to one side at rest (which you don't want). However, it's easy to just stretch it out a little bit and then it's back to normal.
If you stretch the hinge of the HingeAct too far, you run the risk of breaking the hinge or ruining the elastic properties of the hinge spring. It will probably still work if you do this, but the hinge will be floppy with reduced centering force.

Check this video that shows the technique in detail: Hingeact Stretch the hinge