A Good Wheel, Continued
Hold the axis!
The third factor for precision is how well the axis is held. Obviously, if the axis starts to move, precision is lost. The easiest way is to fit the axis into a plastic sheath. The most sophisticated solution is to use a proper ball-bearing system. So, it's pretty clear that making a wheel is not as easy as it looks. Especially because the physical pressure on a wheel and pedals is much greater than that placed on a joystick, and therefore these components need to be able to take the pressure, and well. There are usually two axes, and so there are two potentiometers, one on the wheel and one on the pedals. The pedal set can be divided into separate axes and so they can integrate two potentiometers.
Back to the center
There is just one more factor that has an indirect influence on precision, namely, the return spring. This is what is normally would bring the pedals back to their forward stop position or the wheel to its center. It has to be strong enough to stop the wheel from going slack and, above all, good enough to ensure that neutral is always remains the same.