- Yes they should “center” (in real life they would return to a position based on rudder trim, but for sim purposes, they return to their center position)
- The force required depends on how much rudder input and how fast you’re flying. However for sim purposes just build in enough tension so they return to center and do can definitely “feel” any input you need to make (or you’ll be slipping down to the runway the whole time if you’re not keeping an eye on your turn-and-bank indicator)
Over and above the rudder input axis, you’ll need a braking axis for each pedal so that you can control the braking of the left and right wheels.
If you get fed up trying to make these things I can recommend the Thrustmaster TFRP rudder pedals. Everything you need, low price, lasted me a long time. If you’re willing to spend a little more I now have the Turtle Beach VelocityOne rudder pedals with Hall effect sensors. Slightly better in my opinion, more than double the price though.