Are you sure that both servos can turn all the way to 0 (zero) and all the way to 180 degrees?
Here's a simple test sketch.
/*
Connect servo to pin 9 on UNO or Nano.
Try this test sketch with the Servo library to see how your
servo responds to different settings, type a position
(0 to 180) or if you type a number greater than 180 it will be
interpreted as microseconds(544 to 2400), in the top of serial
monitor and hit [ENTER], start at 90 (or 1472) and work your
way toward zero (544) 5 degrees (or 50 micros) at a time, then
toward 180 (2400).
*/
#include <Servo.h>
Servo servo;
void setup() {
// initialize serial:
Serial.begin(9600); // set serial monitor baud rate to match
// set serial monitor line ending to "NewLine"
servo.write(90);
servo.attach(9);
prntIt();
}
void loop() {
// if there's any serial available, read it:
while (Serial.available() > 0) {
// look for the next valid integer in the incoming serial stream:
int pos = Serial.parseInt();
if(Serial.read() == '\n'){} //skip 1 second delay
pos = constrain(pos, 0, 2400);
servo.write(pos);
prntIt();
}
}
void prntIt()
{
Serial.print(" degrees = ");
Serial.print(servo.read());
Serial.print("\t");
Serial.print("microseconds = ");
Serial.println(servo.readMicroseconds());
}