I removed the plastic stopper from the gears so they are moving
Now the motor won't rotate or do anything.
I can rotate the DC motor by applying 5v to the motor pins itself.
Well, newbies of course carelessly kill their servos. So I have killed a couple, or have their little and big gears scattered all around and could not put them back. Now I know to take a picture of the inside things at every step, and have a small tray ready to place the bits and pieces.
Now which of the YTs below are you following?
Can you show me a zoom in view of your completed job?
Can you show me your Rpi python program?
Before you modify your servo, your program can apply PWM pulses to move and hold the arm to a fixed position, say middle, east, west, up to 180 degrees. Now how do you modify your program to rotate freely to any speed you want, or how many rotations? And do you think you can still position precisely to a particular position? If yes, how, and if no, why not?
Why I need to modify my servo to rotate 360 degrees?
I am day dreaming of assembling a Google like self driving toy car. I have DIYed a tilting platform holding the ultrasonic sensor, controlled by one servo, and the platform controlled by another stepping motor or servo, which should turn 360 degrees, ...
Now the OP has recommended the following tutorial from raspberypi.com. I need to spend time carefully reading it.
Raspberry Pi Python Servo Motor control
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Control function for a DC servomotor angle