On gfi pedal steel guitars basically the strings are tuned to their open pitches using the tuning keys or keyless knobs and the pedal and knee lever changes are fine tuned using the nylon nuts accessible through the window at the changer end of the guitar the student models have a slightly more involved tuning procedure.
Pedal steel changer finger.
Tune the changer for the pedal or knee lever that you are setting up reach under the guitar and push the bridge finger for one of the strings you plan to raise left all the way until it hits the body of the guitar.
The changer on steel guitars is the heart of a pedal steel guitar no question.
Hold it there and tune with the left hand at the keyhead tune the string.
In this configuration the raise finger goes up and around the bridge pin finger shaft and resides next to the control finger.
Changer all pull the changer is the heart of a pedal steel guitar.
If this still does not give you enough pull the pedal stop may be the reason.
The lower a pull rod is located on the bell crank finger the farther the changer finger will be pulled.
How they are designed controls how well they stay in tune and how temperature affects tuning cabinet drop and many other things that we just take for granted.
This movie shows ross shafer making changer finger stops for the new sierra pedal steel guitar.
If adjustable the pedal stop can be tightened or loosened to increase or decrease the pedal travel distance.