Nice tip and good-looking work on grinding away the motor’s breaker pin, among other useful insights to understanding your servo motors.
I am going to show you how to modify a servo motor to allow it to spin around with an unlimited range. Doing so will give you a powerful geared down motor for the cost of a servo.
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.